AN ABSTRACT OF THE THESIS OF HASONG PAK for the DOCTOR OF PHILOSOPHY (Degree) (Name) in OCEANOGRAPHY presented on July 14, 1969 (Major) Title: THE COLUMBIA RIVER AS A SOURCE OF MARINE LIGHT SCATTERING PARTICLES Abstract approved: Redacted for Privacy orge F. Beardley, Jr. The Columbia River plume region was investigated during the period of ZO June to 3 July, 1968 by light scattering measurements and standard hydrographic station observations. The Columbia River plume was traced by the light scattering particles of the plume water. The light scattering particles are estimated to be contained in the plume water for 30 to 50 days. On the basis of the data taken in the Columbia River plume region, a conceptual model is made to describe the flow of river originated particles to the ocean water. In the distribution of the light scattering particles a northward deep current under the plume near the river mouth and a subsurface offshore flow near the bottom of the Columbia River plume are shown. The Columbia River as a Source of Marine Light Scattering Particles by Hasong Pak A THESIS submitted to Oregon State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy June 1970 APPROVED: Redacted for Privacy Ass in charge of major Redacted for Privacy C hairm.n of Department of ceanography Redacted for Privacy Dean o'f Graduate School Date thesis is presented Typed by Donna L. Olson for \cJ) (k9 Hasong Pak ACKNOWLEDGMENT The author is deeply indebted to Dr. George F. Beardsley, Jr., my thesis advisor, for providing the indispensable means and needs for the investigation. He also would like to express his sincere appreciation to Dr. Robert L, Smith, who provided many constructive criticisms and advice, Kendall Carder, who helped in light scattering measurements, data reduction, and error analysis, and Robert Hodgeson, who also helped in error analysis. Special thanks are due to Dr. P. K. Park, who provided space and water samples on the 6806C Columbia Plume Cruise. This investigation was supported by the Office of Naval Research, Grant No. 1Z86(1O). TABLE OF CONTENTS Page INTRODUCTION Problem History 1 1 3 EXPERIMENTAL PROGRAM 5 INTERPRETATION OF SEA WATER LIGHT SCATTERING 10 DATA DATA 14 RESULTS 55 General Features of 1968 Summer Columbia River Plume Flows Model Plume 55 67 73 DISCUSSION 77 BIBLIOGRAPHY 90 APPENDIX I - COLUMBIA RIVER AND ITS ESTUARY 94 APPENDD( II REVIEW OF REGIOi'AL OCEANOGRAPHIC CONDITIONS OFF THE OREGON-WASHINGTON COAST APPENDIX III - BRICE PHOENIX LIGHT SCATTERING PHOTOMETER 97 100 LIST OF FIGURES Page Figure 1. The cruise track and positions of the hydrographic stations of the R/V YAQUINA 6806C, 20 June to 3 July, 1968. Section I follows closely to the plume axis, and sections II to V are approximately along the latitude. 8 An example of the volume scattering function for coastal and oceanic water, and the theoretical curve for pure water (Spilhaus, 1965). 11 3. Salinity distribution on the sea surface. 30 4. Scattering particle distribution on the sea surface. 31 5. Salinity distribution on the 3m surface. 32 6. Scattering particle distribution on the 3m surface. 33 7, Salinity distribution on the lOm surface. 34 8. Scattering particle distribution on the lOm surface. 35 Salinity distribution on the ZOm surface. 36 Scattering particle distribution on the ZOm surface. 37 11. Salinity distribution on the 30m surface. 38 12. Scattering particle distribution on the 30m surface. 39 13. Salinity distribution on Section I. 40 14. Scattering particle distribution on Section I. 41 2. 9. 10. Page Figure 15. Temperature distribution on Section I. 42 16. Sigma-t distribution on Section I. 43 17. Oxygen distribution on Section I. 44 18. Salinity distribution on Section II. 45 19. Scattering particle distribution on Section II. 46 20. Temperature distribution on Section II. 47 21. Sigma-t distribution on Section U. 48 22. Oxygen distribution on Section II. 49 23. Scattering distribution on Section III. 50 24. Salinity distribution on Section III. 51 25. Scattering particle on Section IV. 52 26. Salinity distribution on Section IV. 53 27. Scattering particle on Section V. 54 28. Temperature and salinity vs. depth curves for stations MC-5 and MC-6. 56 29. Sigma-t distribution on the 3m surface. 58 30. Temperature distribution on the 3m surface. 59 31. Columbia River plume axes defined by salinity, 32. temperature, sigma -t, and scattering particle on the 3m surface. Salinity distribution at sea surface, Brown Bear Cruise 308, 7-19 June 1962 (Budinger et al., 1964). 33. 61 65 Temperature vs. scattering particle on Section II. 70 Figure Page 34. Distribution of Holocene clay-mineral groups. 72 35. Plume model in the vertical section along the plume axis. 75 Plume model on a section across the plume axis. 76 37. Scattering particle profile at MC-5 and MC-6. 80 38. Stability (Brunt-Vaisrd. Frequency) profiles at MC-5,6. 81 Profiles of stability and scattering particles at MC-25, near the river mouth. 82 Profiles of stability and scattering particles at MC-33, at the edge of the plume. 83 41. Stability profiles at MC-5 and MC-15. 85 42. Columbia River basin. 95 36. 39. 40. LIST OF TABLES Table Page Columbia plume cruise data, 1. 6806C 2. Meridional components of geostrophic current and Ekman transport. 3. Results of error analysis. 16 66 108 THE COLUMBIA RIVER AS A SOURCE OF MARINE LIGHT SCATTERING PARTICLES INTRODUCTION Problem The various dissolved and suspended substances in the ocean produce optical properties which vary markedly from place to place. A systematic method of interpreting the spatial and temporal distribution of these properties will assist in the solution of many oceano- graphic problems. Such a systematic approach to the analysis and interpretation of optical properties must include considerations of the sources, sinks, and reservoirs of these particles. Rivers are sources of optical properties just as they are sources of fresh water. The Columbia River is the major river bringing fresh water from the North American continent to the North- eastern Pacific ocean. This thesis is the result of an experimental effort to understand the process by which particles are introduced into an oceanic region by a localized source (a major river), and to develop a conceptual model which describes the basic process by which rivers introduce one type of optical property, light scattering by particulate matter, into the ocean. The experimental program was carried out in the Columbia River plume region. 2 Light scattering by suspended material is the specific parameter studied in this thesis, and the word "optical property" is used to imply this scattering property. The process of light scattering has been treated theoretically by the application of electromagnetic wave theory. Mie (1908) derived a rigorous expression in this way for the light field resulting from the scattering of a plane monochro- matic wave by spherical, non-absorbing particles. He showed that the light scattering depends in a complicated way upon the particle size and relative index of refraction. However, assuming that the particles are separated by at least three times their radii and scattered light has the same wavelength as the incident light, then one useful consequence of the Mie theory is that the scattering by a system of particles is the sum of the scattered light from individual particles. Thus the light scattering is directly related to the particle concentration. Theoretical analysis of light scattering to obtain particle sizes, shapes, and constituents is not possible with present techniques, thus an experimental method is needed. Since for a given set of those parameters, a unique scattering field is derived, the study of changes in the scattered light reflects the variations in these parameters themselves. 3 History The progress of optical oceanography has been slow mainly because of the difficulties in making suitable instruments. Kalle (Jerlov, 1968) applied the photoelectric cell and made a scattering meter to determine particle distributions in the deep ocean. Jerlov (1953) made an extensive application of these optical properties of sea water to the study of water masses and circulation. During the Swedish Deep Sea Expedition (1947-1948), Jerlov (1953) determined the particle concentration using the Tyndall meter measurements. He applied the method to an identification of water types, the Equa- tonal current system, deep water circulation, and particle detachment from bottom sediments in connection with bottom topography. Jerlov (1959) applied the turbulence and diffusion theory to describe the vertical particle distribution and presented several empirical measurements. He concluded the following: . . . It seems established that there is often an indisputable relationship between particle distribution and salinity distribution inasmuch as particle distribution is much controlled by the turbulence and ultimately by the flow of the different water masses. * The application of light scattering measurements to the outflow of river effluent has been made by Jerlov (1953a, 1953b and 1958) and by Ketchum and Shonting (1958). These studies are considered incomplete due to insufficient area coverage. The Po River plume, 4 studied by the former author (1958), provided a comprehensive guide to the problem, but geographic and hydrographic conditions of the plume region complicated the results, The latter authors traced the Orinoco River plume in the Cariaco Trench, which is more than 250 nautical miles from the source. Their findings are considered incomplete since the path between the region of the studied plume and the source of the plume was not studied. It seems imperative for the interpretation of the measurements made in the Cariaco Trench to consider the progress of the plume between the source and the Cariaco Trench, The parti- cle constituents, sizes, shapes, and dispersion processes of the plume may or may not support the interpretation made by the latter authors on the particle distributions observed in the Cariaco Trench. On this basis, a thorough study of the optical properties at their source region is believed to improve and extend the use of these properties. 5 EXPERIMENTAL PROGRAM An ideal scientific experiment is one in which the whole system can be controlled. Usually such controlled experiments are not feasible in oceanography, so field experiment programs must be used instead, A good field program is easiest to develop when the phenomena to be studied are simple, with a well defined geometry, and with features that vary slowly in comparison with the possible speed of survey. Approximations of synoptic observations, which are often practiced in oceanographic works, are based on such conditions. The availability of supporting data from previous studies is also helpful in planning field programs. The Columbia River plume region was considered excellent for the proposed study. The use of the Columbia River water as a cool- ant for nuclear power plants at Hanford has motivated many prior cruises in the plume area, and the basic physical, chemical, biological, and geological features are well known (References are given in Appendix II). The plume is well developed during the summer months, and shows a persistency during this season. Previous studies (Budinger et al., 1964; Frederick, 1967; and Cissel, 1969) have shown that fourteen days at sea are sufficient to obtain an accurate and nearly synoptic picture of the plume during the summer in a region about 100 by ZOO nautical miles. The oceanic region into which the Columbia River effluent flows is characterized as an Eastern Boundary current region of the North Pacific Ocean with a weak but recognizable southward surface flow during the summer. North or Northwesterly wind persists during the summer, and coastal upwelling is observed along the coasts of Washington, Oregon, and California. Thus during the summer, the weak southward surface current, a persistant north or northwesterly wind, and upwelling along the coast cause the Columbia effluent to form a tongue-shaped plume extending toward the south or southwest. This plume is bounded by upwelled water on the coast side and by clear oceanic water on the offshore side. It is clearly identified by a salinity minimum. The Columbia River plume maintains a well defined, simple form during the summer because the dry regional climate during that season eliminates the complicating effects of coastal streams, and the persistent wind system keeps the plume position at an approximately steady state. Further details of the Columbia River, its estuary and regional oceanographic conditions are presented in Appendices I and II. The Columbia River plume cruise (6806C)1 was planned to study the physical, chemical, and biological aspects of the Columbia 'The 6806C Cruise was planned and executed by Dr. P. K. Park 7 River plume and its environmental water during summer upwelling conditions. The addition of an optics program to this cruise allowed us to obtain the data required for this study. The cruise took place during the period of June 20 to July 3, 1968, and included 67 hydro- graphic stations and another hundred auxiliary stations of bucket samples placed between hydrographic stations (Figure 1). The data obtained at each hydrographic station and used in this study include temperature, salinity, dissolved oxygen, and light scattering, listed in Table 1, along with computed values of sigma-t (density) and the stability parameter (Brunt-Väisälä frequency). All the measurements were made on samples taken with Teflon-coated Nans en-bottles. The hydro-casts and samples were taken according to standard procedures. The temperature was measured by reversing thermometers attached to the Nans en-bottles. The salinity was measured by an hlHytechH inductive salinometer, The dissolved oxygen was measured by the Winkler method. Light scattering was measured in the ship?s laboratory with a Brice-Phoenix light scattering photo- meter. This instrument measures the light scattered by a water sample contained in a glass scattering cell. The instrument and its operational procedures are presented in Appendix LII. The standard sampling depths were 0, 3, 6, 10, 20, 30, 40, 50, 75, 100, 125, and 150 meters. A BT was cast before each . .uoô. a I.-___ -...- / - S_/' S. ''n ó - R. ! ---"/ 0:o . SC O . 0:,, 6. a a.-' SECT ION / o ' ) \ I ,A r a I 2 3' I' w/ ' in - -11 ---// / II 0. i /0 04 in çsj F() in' &. --c I) in / 0 ,. N? ,,/' . (cjJ' -_. SECTION V a: 5, '0 (. .0 , °N I...' : I:.: ' k.- .5 'I 0 0 o 0 0' 0 2 F::'.' I 0 '/EIU) N) i-I . 1. 0 0 sIC)' I:: N-:f- 5' , 0 i Figure 1. The cruise track and positions of the hydrographic stations of the RIV YAQUINA 6806 C, 20 June to 3 July, 1968. Section I follows closely to the plume axis, and sections II to V are approximately along the latitude. hydro-cast and additional Nansen-bottles were added to the standard depths whenever significant features, such as temperature inversions or any other rapid changes with depth,were found on the BT slide, Since the casts were all shallow and made under good conditions, no corrections for wire angle were necessary. 10 INTERPRETATION OF SEA WATER LIGHT SCATTERING DATA The volume scattering function, p(8), is defined by: J(6) (8) HV (1) where J(0) is the intensity of scattered light in the direction of 8, H is the input irradiance, and V the scattering volume defined by intersection of the light beam and the detectivity beam. Figure 2 shows three observed volume scattering functions plotted against scattering angle, 8. The total scattering coefficient can be defined by: (111 b = Zrr 13(8) sin8dO (2) 0 The total scattering coefficient is usually computed from 13(8) measured at certain intervals of 0. The measurement of 13(8) at a small angle is considerably difficult, and a separate instrument is usually used for the small angle measurement (Spilhaus, 1965; and Morrison, 1967). FTom the regular behavior of the angular dependence of the volume scattering function, Jerlov (1953a), Tyler (1961c), Spilhaus (1965),*and Morrison (1967) concluded that the total scattering coefficient can be computed by 13 13 (45) with small error showing b and (45) are linearly dependent. Thus the total scattering coefficient 11 0C OASTAL 0 0 0 0 OCEANIC 0 0 o 0 0 00 00 0000000 0 D C C C A THEORETICAL 300 600 c00 90° 1200 1500 L!J Figure 2. An example of the volume scattering function for coastal and oceanic water, and the theoretical curve for pure water (Spilhaus, 1965). 12 in the form of equation (2) is not computed considering 1) 3 (45) is an adequate substitute for b, 2) more time involved in measuring () at many angles to apply equation (2), and 3) the difficulties in small angle (0) measurement, which has some uncertainty remain- ing. According to the Mie theory, the scattering coefficient from N particles per unit volume can be represented by: b=KNirD2/4=KNA (3) where K is efficiency factor or the effective area coefficient, D is the diameter of the particles, and A is the cross-sectional area of particle. In case of polydispersed particles, the scattering coefficient is given by: b K. N. (4) Burt (1956) computed the effective area coefficient, on the basis of Rayleigh's equation and Mie theory for non-absorbing spheres, as a function of refractive index, size, and wavelengths. With increasing particle size, K increases rapidly at small radii, then it passes a maximum for sizes of the same order as the wavelength, and it tends thereafter toward a constant value of 2 for larger radii irrespective of the wavelength. 13 On the basis of the equation (3) or (4), the scattering coefficient measured in sea water can be interpreted as a measure of particle concentration with a mean diameter D Particularly for a system of polydispersed particles in which the mean size remains constant, or D N' then the volume scattering function measured at 450, p (45), is proportional to the concentration of particles. 14 DATA The final reduced data are listed in Table 1, The data were analyzed on horizontal surfaces at several depths and in vertical sections along the plume axis and across the plume axis, Figures relevant to the discussion and results are listed below and collected in the following pages. The volume scattering function measured at 450 angle is ex- pressed in absolute unit of (meter-steradian) Through the rela- tion between the total scattering coefficient and the volume scattering function measured at 450 section, 1 P (45), as described in the previous (45) is directly interpreted as a parameter indicating suspended particle concentrations. List of Analysis Figure 3, Salinity distribution on the sea surface, 4, Scattering particle distribution on the sea surface, 5. Salinity distribution on the 3m surface, 6. Scattering particle distribution on the 3m surface, 7. Salinity distribution on the lOm surface. 8, Scattering particle distribution on the lOm surface, 9, Salinity distribution on the ZOm surface, 10, Scattering particle distribution on the ZOm surface, 15 11. Salinity distribution on the 30m surface. 12. Scattering particle distribution on the 30m surface. 13, Salinity distribution on Section I 14, Scattering particle distribution on Section I. 15, Temperature distribution on Section L 16. Sigma-t distribution on Section I. 17. Oxygen distribution on Section I. 18, Salinity distribution on Section II. 19. Scattering particle distribution on Section II. 20. Temperature distribution on Section II. 21. Sigma-t distribution on Section II. 22. Oxygen distribution on Section II. 23. Scattering distribution on Section III. 24. Salinity distribution on Section III. 25. Scattering distribution on Section IV. 26. Salinity distribution on Section IV. 27. Scattering particle distribution on Section V. 16 Table 1. 6806c Columbia Plume Cruise data. 2 DB-1 10 31 8.22 5 0 5 10 20 30 4o DB-5 50 0 5 10 20 30 40 50 60 DB-7 0 5. 10 20 30 4o 50 6o 70 80 90 100 DB-10 0 5. 10 20 30 40 50 60 70 80 90 100 125 TDB-15 LI 10.08 9.17 8.68 7.95 io.06 9.10 8.96 8.18 7.41 7,21 7.22 11.73 10.79 9.53 7.83 7.75 7.62 7.45 7,10 12.67 11.36 9.55 7.89 7.62 7.71 7.64 7.41 7.35 7.19 7.05 6.98 14.17 13.54 10.27 8.35 7,75 7.70 7.68 7.74 7.56 7.35 7.22 7.16 6.93 14.75 13.95 0 10 20 DB-3 T 0 20 r'.50 S Ni 02 S45 S90 (mi/i) 32.959 33.290 33.L1.5 33.65 32.794 33.137 33.202 33.369 33.803 33.884 33.888 31.208 31.763 32.150 32.934 33.352 33.632 33,756 33.899 33.932 33.888 33.860 33.843 33.746 33.532 33.419 33.162 32.716 32.066 31.720 30.631 30.353 31.496 31.919 32.355 32.747 33.085 33.340 33.583 33.682 33.816 33.866 33.901 33.949 29.526 31.805 31.925 32.247 5.6 4.46 3.81 2.52 ,64 4.53 4.39 3.17 2.12 1.54 1.46 6.6i 6.35 5.31 4.05 3.46 2.60 2.32 1.87 1.88 2.55 2.74 2.88 2.i0 3.13 3.44 3.95 4.41 25.36 25.77 25.98 26.25 25,24 25,66 25.74 25.98 26.44 26.53 26.53 23.71 24.31 24.83 25.70 26.04 26.28 26.39 26.55 23.10 24.18 24.75 25.52 2.91 26.09 26.19 26.39 26.49 5.48 2.52 6.70 6.69 6,44 6.56 6.84 4.95 4.31 4.15 3.88 3.38 3.08 2.78 2.76 2.70 26.55 26.60 22.59 23.59 1.60 6.39 6,30 7.11 5.61 24.2 25.17 25,56 25.84 26.04 26.22 26.32 26.45 26.51 26.55 26.62 21.83 23.77 24.51 25.10 2.975 2.008 1.657 2,901 1.238 1.63 2.139 .9547 --------3.463 3.201 2,Q48 1.947 i.5L4 1.73 4.654 3.375 2,759 1.979 1.353 1.021 1,40? .9331 .197 .5949 .7004 4.481 4.295 2.542 1.983 1.655 1.438 1.340 1.022 1.150 .7598 .6316 .5049 4,4oi 2.706 2.436 2.046 9.9694 10.954 3.7758 47343 4.1484 5.5949 3.0679 4.8993 4.1786 5.0924 3.4251 4.7186 2.0741 2.4429 2.4086 3.2215 2.0173 3.2450 2.0037 3.1766 2.6520 3.7981 3.1312 3.4651 4.1571 4.o75 2,1977 2.7694 1.4583 2.1185 1.0858 1.8353 1.3921 2.3506 1.9191 3.2491 1.1353 1.4008 3.9774 5.6259 1.4694 2.5910 1.1190 2.1299 1.3215 2.3781 .72796 .88172 9Y-o3 1.7696 .27741 2.0347 i.07c4 1.Q79 1.4208 3.0025 2.5326 3.3030 3.4528 Li..6652 5.8627 8.2474 2.8980 3,3557 2.2710 3.0552 2.23R1 2.4483 1.2367 1.9090 1.2317 1.9i6 1.6739 2.232 1.2857 2.2886 1.1335 2.0844 1.4553 3.1066 .87232 1.6537 1.9179 3.5635 1.9168 3.0723 5.2577 3.8258 2,4970 3.122 1.4658 2.2134 1.029 1.8043 17 (continued) Table 1. Z T S DR-IS 3 7,75 32.426 4() 7.81 7.84 32,58 45 50 60 70 80 90 100 125 149 DB-20 0 20 30 40 59 60 70 75 20 DB-25 7.R1 7.81 .76 7.61 7.3? 7.01 6.66 14.78 2,92 9.17 ,74 Q,19 7,63 7.70 ?.0 7.73 .73 7,62 32.724 32.206 33.124 33.401 33.572 33.657 33,777 33.910 33.959 29.603 32.279 32.372 32,428 32,475 32.234 33.202 33.338 33.427 3.540 33.639 33.727 33.877 90 100 125 150 7.63 7.10 (-.80 33.95 0 1.3Q 10 20 13.86 12.15 9.42 8.82 8.82 8.53 8.35 7.99 8.21 8.13 8.05 28.080 31.936 32.147 32.414 32.449 32.442 32.488 32.614 32.712 32.949 33.093 33.163 30 40 .50 60 70 75 80 85 0 100 125 150 DB-30 790 0 50 75 86 91 lot 111 121 130 140 150 7D4 3.315 5.84 5.81 4.31 !i57 4.60 3.82 3.54 3.16 2.71 2.53 2.30 6.40 7.16 7.05 6.63 6.18 4.85 4.27 3,27 3.64 3.40 3.07 3.20 2.46 2.38 6.27 6.34 6.92 7.13 6.87 6.70 6.31 6.02 5.56 5.17 4.85 4.69 4.33 3.44 7.93 7.10 16.09 9,00 8.33 8.32 8.31 0,20 8.17 8.12 7.93 7.81 7.65 Ni 02 S45 S90 (mi/i) (°C) 33.871 26.499 32.447 32.809 33.055 33.222 33,479 33.612 33.640 33.713 33.788 33.821 2.49 6.26 6.90 5.50 4.95 4.72 4.12 3.78 3.67 3.59 3.46 3.30 25.31 25.40 25.53 25.61 25.85 26.07 26.21 26.29 26.42 26.58 26.66 21.89 24.86 25.06 25.16 25.28 25.57 25.93 26.01 26.09 26.19 26.28 26.34 26.54 26.64 20.60 23.79 24,36 25.04 25.13 25.17 25.24 25.37 25.50 2.65 25.78 25.84 25.98 26.27 26.54 19.23 25.14 25.52 25.72 25.85 26.o6 26.18 2.21 26.29 26.37 26./42 1.366 i.6o6 1.288 1.533 1.481 1.186 .81544 .63250 1.7834 1.1006 .91483 1.0920 .S0005 1.13.5 1.208 .8023 1,1367 1.0714 .o3942 2.4559 .17 .75 ---- 3.Ri 1.409 1.028 1.104 1.688 1.893 1.322 1.271 1.372 l.31 .8312 .8802 .6475 .4372 5.652 2.391 .9467 .96973 .8561P .74369 .82060 1.3414 1.1202 1.2'425 1.2607 1.2563 .373'J2 .03307 2.5707. 1.2248 2.93 1,013 .9562 .5973 .8693 1.135 1.623 1.717 i.6n8 1.155 1.4255 1.6434 .89434 .94445 .98506 1.0110 .68275 .77413 .73198 .884qo .73322 1.6654 2.5675 1.1923 .77895 .79265 .80357 257LL9 1.4467 i.i6 1.026 1.042 .5717 3.436 1.239 1.338 1.640 1.457 1,068 .5570 .9621 .8524 7L144 ---- 1.6300 1.2649 3.0257 1.8591 1.7057 2.1758 1.6138 2.7850 2.1712 1.8715 2.0171 3.0960 1.6900 1.6667 1.6674 1.3456 1.6282 2.4161 1.9781 2.3664 2.4743 i.9899 .42975 1.6391 3.133 2,2705 2.0868 1.9301 2.0218 1.7732 1.8255 1.9347 1.6603 1.3922 1.5283 1.3088 1.6230 1.3716 2.8878 .6063 3.0607 2.1669 1.4735 1.4276 1.5277 1.2074 2,7109 1.1741 .60744 12334 1.°127 2.9974 18 Table (continued) 1. Z St't. DB_LI.0 0 50 60 70 80 90 100 125 150 0 3 6 10 20 30 50 55 60 16.70 13.96 11.79 10.16 0.72 9.35 0.02 8.1 S.4i 8.41 9,20 .12 7.84 16.25 16.22 16.24 15,86 12.28 o.84 0.38 9,1 8.20 8.91 5 89Q 70 75 9,75 8,72 100 150 .j6 0 3 6 10 20 32 40 50 75 100 150 MC-3 Ni 02 S45 0 3 6 10 20 30 4n 50 75 100 105 149 7.60 15.53 14.58 i5.c4 i.28 1.62 12.21 10.64 9.90 8.82 8.11 900 25.206 31.679 32.474 32.525 32.c32 32.535 32.555 32.727 32.978 33,22 33.421 33.711 33,838 20.940 2P9t2 20.020 30.369 32.lco 32.380 32.457 32,521 32.572 32.657 32.770 32.953 3329 7.79 4.24 3.49 3.10 5,92 5.97 5.89 6.76 5.98 7.37 7.13 6.47 6.16 5.Q .89 5,43 .09 18.12 23.65 24.69 2501 25.09 25.15 25.22 25.43 25,63 25,89 26.03 26.27 26.40 21.83 21.86 21.82 22.24 24.35 24.96 2,09 2.18 25.25 25,32 25,41 25.7 33.327 33.777 31.634 31.626 31.633 31.769 32.356 32.459 32,492 32.497 32.610 U.3 25.66 26.01 2.85 26.' 5,94 .03 5.05 5.95 6.31 6.78 7,03 7.14 23.29 23.49 23,29 23.44 24,24 24.60 33.16 4,99 3.40 5.90 5.04 33.790 15.86 30.94 30.93 15.82 15.86 30.93 1.77, 31.18 32.62 13.59 32.37 12.89 9.96 32.42 0.15 32.44 8.51 32.46 33.16 7.89 9.1.8 6.08 6.32 6.00 7.24 7.05 6.68 6.32 5,79 5.43 4.75 33.31 33.95 6.I 5.92 5.95 6.28 6.55 7,20 7,30 6.20 14.96 4.51 3.08 S90 (3) (mi/i) 20 30 MC-2 S J 10 1C-1 T 2LJ.91 25.04 25.30 25.82 26.36 2268 22,69 22.68 22.89 24.45 24,40 24.07 2.11 25.23 25.87 25.94 26.42 7.435 3.'21 1.718 .8970 .7726 .8232 1.454 1,420 i.cio 1.284 1.004 1.7008 1.7081 .96888 1.026 .02018 1.4200 .73563 .60261 1.6153 1.0750 .o6?56 .7291 1.293 --- 1.2450 1.1858 .96718 .80989 1,2185 .87247 1.0284 1.1616 .61388 .67832 .93750 .85757 1.4523 .89961 .oi8o4 1.7180 .78142 p77476 .85013 .73423 .85085 1.0224 .91625 .93443 2.3084 1,2409 1.1609 .84870 .88025 1.2224 R4 --3.242 4.c9 2.464 1.l3 .0544 1.250 1.124 1.302 1.802 1.287 1.185 .9725 2.548 1.278 2.930 1.891 1.750 1.142 1.018 1.450 1.042 --.1962 --2.298 3.958 --2.378 1.209 .6767 1.602 1.206 1.045 .5507 .91711 1.042 .05831 i.6636 1.6156 1.4354 1.3144 1.7636 .88342 2.0905 2.6845 1.7311 2.1313 1.9886 2.0534 1.9738 1.2467 3.3100 1.8652 1.7712 2.3308 2.0276 1.7200 1.7255 1.570 1.8697 1.5827 2.1088 2.2708 1.4073 1.3919 1.6845 1.7303 2.4662 1.4692 1.6814 2.8677 1.4008 1.5008 1.4631 1.22.56 1.3789 1.6050 1,6462 1.5285 4.5551 2.5231 1.6946 1.6943 1.6692 2.1076 1.5372 1.7400 1.6921 2.8639 2.3926 3.0454 2,5154 3.0963 1,7590 19 Table (continued) 1. Z Stat. j MC-4 0 3 6 10 20 30 40 50 75 100 149 0 3 6 10 20 30 40 50 70 85 90 95 100 150 ?'lc-6 S 16.Li.LI. 16.36 16.1) 15.03 12.78 10.51 9.79 9.36 8.87 8.41 7.73 16.76 16.53 1.57 i.i4 12.05 10.13 9.30 92 8.50 8.62 9.13 2.37 9.31 8.24 8.13 28.729 29.42 30.24 31.33 32.24 32.43 32.47 32.48 32.72 32.5'? 32.62 33.13 33.27 33,3 33.41 25.94 3 16.79 16.42 2.29 6 1.97 10 l'i)L4 3,Lj 20 9.7 32.20 37,39 30 '06 40 .74 0 8.51 8.02 7.84 7.21 16,47 3 1.73 1/49 6 10 30 SQ 55 60 65 70 75 80 15.17 14.89 7.90 7.77 7,97 7.89 7,86 7.87 7.83 774 5.92 5.95 5.99 6.08 6.75 7.24 7.28 7.09 5.93 31.16 32,45 32.Q9 33.53 33.4 26.105 28.78 30.17 30.67 32.37 32.87 33.09 33.23 33.34 33,42 33.51 33.56 3.38 6.04 6.15 6.16 6.17 6.88 7.31 7.24 .68 --6.25 6.22 5.11 4.75 4.64 4.42 6.21 ,27 6.37 6,49 7.30 7.03 6.6o 6.47 .12 3,81 2.2 6.45 6.46 6.40 6,46 5.16 5.01 /4.81 4.59 4.28 4,21 4.00 3.67 S45 S90 j 20.86 21.41 22.09 23.16 24.32 24.88 25.04 25.11 25.38 4.55 33.77 27.32 27.68 30.81 31.52 32.22 32.44 32.42 32.45 32.40 33,9/4 0 Ni 02 (mi/i) .73 75 100 MC-7 T 26.37 19.72 20.05 22.65 23.29 24.45 24.96 25.08 25.17 25.25 25.30 4.290 4.753 5.182 3.402 2.366 1.237 .8698 1.029 7.307 .61A9 3.292 9.313 3.992 3.402 2.151 1.093 .9924 .8951 .9413 1.502 25.11.1 25.77 25.89 25.95 26.03 26.42 18.66 19.76 23.05 23.35 24,8/4 25.10 25.14 2.22 25.72 26.17 26.50 18.85 21.13 22.24 22.69 25.25 25.66 25.99 25.92 26.01 26,07 26.15 26.20 1.540 1.073 1.258 .899? 6.059 10.46 2.753 3.856 1.605 .6815 .8781 1.408 1.341 .2260 9.705 6.096 3.327 3.57? 1.433 1.693 1,559 1.346 1.107 1.236 1.023 1.235 1.6961 1.1998 .97840 1.1227 .97788 1.1427 1.4467 .72316 .99963 .66110 .98260 1.3506 3.9800 6.9934 1.8726 1.3538 .84853 1.6453 1.0242 1.3820 2.5339 .76698 1.1381 .61793 .75626 2.2366 .77713 1.3713 1.9488 1.6439 1.3203 1.6120 .87785 1.5118 1.3635 1.0077 .H1022 1.6867 2.5290 2.0403 1.7376 1.8467 1.5651 2.1772 2.2560 1.5763 2.0113 1.3008 1.8242 2.1836 6.4732 2.4474 2.4124 2.8343 1.6266 2.3376 1.6855 2.1255 5.2966 1.2734 2.1517 1.3133 1.5619 3,5455 1.4963 2.2203 3.0230 2.3857 1.9389 3.C26 1.4763 1.9162 2.1720 2.0200 1.4989 2,7889 4.8592 ?.T /4.4809 2.5382 2.5629 1.0868 .68628 .87479 .55349 .56849 2.6840 .73826 .75980 3.3389 3.0454 1.9294 1.6799 2,0061 1.2670 1.2927 5.0926 1.6013 1.6645 L8879 20 (continued) Table 1. Z T MC-8 90 7.39 100 7.33 150 6.75 0 15.96 3 15.91 33.699 33.841 33.947 26.167 2..226 6 13. 78 30. 229 31. 592 10 12.38 20 8.48 30 7.53 40 7,47 50 55 60 65 70 75 7.58 7.78 7.88 7.81 7,74 7.66 7.28 6.62 100 150 0 12.56 NC-9 3.10.01 9.67 6 9.34 10 20 7.79 7.72 30 40 7.64 50 7.39 0 12.05 MC-l0 3 11.62 6 11.49 10 11.36 20 7.98 30 7.51 40 7.65 7.50 50 0 12.88 NC-il 3 12.08 6 9.55 10 8,94 20 7.82 7.70 30 40 7.65 7.60 50 75 7.15 0 12.74 MC-12 3 12.76 6 12.75 10 12.08 20 :30 7.82 Ni 02 32.320 32.633 32.8 76 33. 112 33. 304 33. 365 33.440 33.510 33. 543 33. 849 31.223 31. 965 32.175 32.277 32.892 33. 436 33. 6 50 33.801 30. 978 31. 302 31.477 31. 626 32. 618 33.058 33. 530 33. 734 30.42 5 30.859 32. 32. 33. 33. 33. 33. 33. 30. 30. 30. 018 322 098 408 592 792 971 824 847 862 31.168 75 33. 216 7,2; 33. 842 33.746 2.61 2.81 2,51 6.84 6.84 6.61 7.26 4.78 5.24 4.43 3,93 4.28 4.38 4.07 3.83 3,55 2,88 1.78 6.27 5.68 5.39 5,28 4.08 3.10 2.72 2.12 6.09 6.03 6.13 6.16 4.49 4.40 2.88 2.73 6.44 6.22 4.96 4.78 3.77 3.19 2.83 3.01 1.98 6.51 6.52 6.54 6.56 3.'0 2.42 2,15 S45 S90 2) (mi/i) cJ L MC -7 S 26,36 26.48 26.64 19.02 19.07 22.58 23.90 25.13 25.51 25.71 25,88 26.00 26.04 26.10 26.16 26,20 26.50 1.124 23.58 24,60 24.82 24.95 25.67 26.10 26.29 26.44 5.840 2.702 1.808 2.682 2,083 1.357 23.148 3.328 2.314 1.826 3.638 2.024 1.876 23.82 23.98 24.11 25.43 25,84 26.19 26.38 22,91 23.40 24.73 25.05 25.83 26.09 26.24 26.41 '6.6i 23.23 23.25 2.?6 23,f2 25,02 26.3' Lp 5658 1.335 10.80 5.744 3.505 1.951 1.416 1.302 1.551 .8672 1.175 1.102 .8990 1.091 1 .239 1. 3.58 4.055 6.651 2.845 2,792 i.6io 1.237 1.293 .8859 .703 2.P7 4,792 2,150 r)ry) 5 1.1031 .87938 3.0)33 4.8697 4.5601 2.7263 2,9601 1.2495 .84042 .94987 .8266 .70859 .88685 .72413 .81384 .62036 .84265 1.9830 1.6559 4.7373 5.4870 5.5960 3.1772 3.3654 2.0101 1.6014 2.6584 1.7852 1.4586 1.8376 1.5251 1.8416 1.3243 1.4997 3.6908 3,3464 2.9015 2.6362 1.2926 1.1415 1.3030 2.5161 4.5658 5.5601 3.7080 3.1660 1.9408 1.1121 1.3792 4.7159 4.0208 3.7897 3.3647 1.8134 2.0223 .2146 3.4092 5.2094 7.9848 4.5562 3.8251 2.3649 1.7969 1.41.76 2,2957 6.0063 4.7637 4.8996 2.8917 1.9385 1.6772 1.4844 1.5036 1.5527 4.0454 4.1717 4.24.06 4.0205 3.434 2.2447 1.5700 1.0025 2.3ce57 5.3381 3.8417 2.6435 2.6103 2.5453 2.6424 2.4567 5.2041 5.4211 5.4717 5.1139 5.0024 2.8/431 2.7086 3.0328 21 Table 1. (continued) Z § MC-l3 J 50 .89 0 3 6 15.55 15.48 13.72 12.13 9.82 7.79 7.44 7.55 6.8? 6.6o 15.97 15.23 14.17 13.65 12.12 8.74 40 50 75 100 0 3 6 10 20 30 40 50 60 65 70 75 80 100 0 3 7 10 20 30 40 50 75 80 85 90 100 149 MC-17 .2 75 30 MC-16 15.68 13.26 11.01 9.72 7.60 7.42 7.22 10 20 MC-15 S 0 3 6 10 7.71 7.38 7.53 .62 7.48 7,37 7.26 6.86 1.31 15.30 15.09 14.66 13.11 11.72 9,77 9.52 8.19 8.39 8.40 8.23 8.14 7,52 15.24 15,22 15.21 i,i8 Ni 02 S45 S90 (mi/i) ic.i 0 3 6 10 20 30 40 MC-14 T 24.566 29.608 31.640 32.164 33.267 33.587 33.729 33.803 33.938 25.772 2c.965 6.87 6.66 5.58 4.67 3.36 2.73 2.51 2.41 1.76 6.66 6,61 2c,,14Q3 .90 31.462 32.110 32.831 33.356 6.77 4.93 3.75 --- 33.924 33.966 21.268 25.255 30.221 30.927 31.490 32.243 32.743 33.160 33.592 33.571 33.696 33,774 33.91 33.913 31.751 31.739 31.764 31.844 32.394 '32.423 32.!436 32.484 32.670 33.100 33.221 33.397 33.476 33.780 32.149 32.075 32.072 32.070 3.20 '-- 1.73 i.66 6.93 7.01 6.67 6.70 .38 4.78 14.10 3.64 2,80 2.86 2.83 2.93 2.75 2.01 6.03 6.o 6.10 6.18 6.46 7.07 7.32 7.22 6.07 5.09 4.80 4.43 4.28 3.57 6.04 6.05 6.05 6.05 17.85 22.19 24.18 24.81 25.96 26.24 26.37 26.47 26,61 18.80 18.96 22.02 23.84 24,75 25,62 26.08 12.03 8.143 3.940 3.394 1.682 1.165 7.1610 4.6055 4.1537 2.9349 2,3547 8.'4.564 12273 .9548 .7699 1.5275 1.1166 3.3367 6.3011 1,Qc 2,2420 2.4492 1.9667 5,2679 7.4663 8.0102 6.1236 4.4225 3.0080 2.6152 2.i842 --26.61 26.68 10.27 .5232 15.27 19,46 22.87 23.13 23.87 25.01 25.56 25,94 26,26 26/23 26.34 26.41 10.31 12.12 2.542 2.708 3.396 2.332 1.940 1.778 1.5174 2.5209 10.394 6.4398 3.4015 3.6643 3.5277 2,5254 4.1680 12.586 8,0791 4.4053 4.5960 4.4370 1.2533 1.6126 1,5393 1.3801 1.6268 .86690 1.2080 1,9252 1.1814 .89599 .92428 .93123 .73346 2.4018 1.5540 1.5235 3.5047 1.2369 .88564 1.1803 .46570 .48528 .82019 .83428 .74090 .77798 2.1995 2.3101 2.6193 2.2692 2.7478 1.7224 2.4629 2.4561 2.1617 1.7090 1.4900 1.4609 1.3663 2.6683 2.3629 2,2795 3.7735 2.1703 1.7983 2.3006 1.1541 1.0725 1.4020 1.4221 1.2420 1.3465 26,147 26.60 23.43 23.41 23.48 23.63 24.37 24.66 25,01 25.09 25.44 25.75 25,84 26.00 26.07 2,306 10.10 6.751 '3,010 2.957 2,140 - .-- 1.512 1.253 .9700 .8203 --1.307 2.257 2.718 1.693 1.858 .8919 1.191 2.475 1.359 1.782 .8727 .8262 26.141 23,74 23.69 23.69 23.70 --.2686 .4027 2.690 6.446 5.1342 3,5774 2.4674 1.5881 5,5011 5.0645 3.8234 3,5139 22 Table (continued) 1. T Z Stat. MC-17 J 40 50 75 100 149 0 3 6 10 20 30 40 50 75 80 85 90 100 150 MC-19 0 3 6 10 20 30 40 50 7 80 85 90 100 150 MC-20 0 3 6 10 30 40 so 75 80 85 90 100 MC-21 0 3 6 10 70 13,01 11.12 9,69 9.20 R14 8.40 7.62 14.94 14.94 14.°3 14.73 13.06 11.00 9.76 9.15 7.95 7.85 7.88 7,77 7.84 7.80 15.11 15.10 15.12 15.12 13.10 p.46 8.86 P57 7.89 7,98 7.89 7.93 7.87 7.53 14.76 14.73 14.76 13.59 8.25 "57 7,50 7.40 7.64 7,44 7.32 7,26 14.67 14.67 14.65 14.30 9.91 NI 02 S90 S45 (mi/i) j 20 30 ?'C-18 S 32.LJ.30 32.494 32.c09 32.506 32.745 33.290 33.763 31.954 31.959 31.9c7 6.54 7.09 7.26 6.75 5.87 4.54 3.55 *15 .10 6.13 31.QSfl .07 32.360 32,438 32.464 32.462 32.c96 32,737 32.877 33.042 33.232 33.826 31.761 31.758 31.758 31.762 31.858 32.314 32,402 32.434 32.91 33.063 6.50 7.34 7.44 7.08 6.43 6.04 '33,13° 4.84 4.71 4.46 3.65 6.29 6.29 6.28 33.233 33.433 33.803 31.692 31.684 31.684 31.789 32.336 32.531 32.704 33.377 33.536 33.589 33.658 33,777 31.185 31.185 31,185 31.255 32.107 5.68 5.24 4.81 3.17 6.14 6.io '.12 6.10 6.49 7.20 6.79 6.49 .19 .01 .5? 6.15 5.66 5.68 3.73 3.67 3.29 2,89 2,53 6.30 6.30 6,30 6,40 6,6o 214.42 24.82 25.07 25.15 25.44 25.89 26.38 23.66 23.67 23.67 23.72 24.36 24.81 25,04 25.13 25.41 2.55 25.65 25.79 25.93 26,41 23.48 23.48 23.48 23.47 23.98 24.97 25.13 25,20 25.67 25.78 25.86 25.02 2.09 1.995 .8364 1.077 i.34'4 .9944 - ---1.182 2.524 2.108 1.517 .9888 1.057 1.635 i,45i 1,670 1.196 .9751 ---------2.262 2.131 1.282 .8416 1.376 1.463 1.218 1.125 1.298 .8277 .0769 2.8214 2,603 1.589 1.189 1.476 1.322 1.222 1.194 .9881 26.4' 23.13 23.13 23.13 23.26 24.74 1.4209 1.8414 1.8062 2.0668 2.7615 2.0663 - .3578 26.1.i3 23.50 23.50 23.49 23.81 25.17 2c.4i 25,57 26.11 26.20 26.27 26.34 .7599 1.1375 1.0537 1,1454 1.3110 1.0554 .2640 .2640 1.748 3.846 2.292 .68199 .7c602 ,7o528 .56820 .92741 1.7207 1.0387 1.0768 1.1754 .98415 1.1314 .49402 .60674 .56401 .97769 1.1626 .95543 .79363 .84623 4.9769 .95203 .64529 .68989 .70587 .60394 4.7995 .59201 .57713 2.0694 2.1289 2.0065 2.3403 1.3464 1.1803 .89450 1.1466 .99018 1.3784 1.1934 12447 ---3.730 - 1.5Ah6 1.3910 1.4844 1.2066 1.1020 1.3958 2.9793 1.8659 1.7523 1.9565 1.8983 2.6758 1.2381 1.2539 1.2684 1.4445 1.7590 1.5711 1.3753 2.1283 2.1189 1.8369 1.0999 1.2177 1.5330 1.3811 2.1622 1.3223 1,3543 2.7514 2.7757 2,5344 2.6447 1.8818 2.1729 1.4831 2.0929 1.8199 2.6081 1.9632 2.1829 3.4377 3.6010 3.9583 3.9290 2.1422 23 Table 1. (continued) Z - MC-21 40 7,411. 50 7.46 7.13 6.50 13.94 13.93 13.92 13.29 8.86 8.42 7.66 7.33 0 3 10 15 20 30 40 50 7.31 0 3 14.67 13.25 13.34 12.73 9.79 8.25 17.10 16.o6 16.65 15.06 9.07 12.05 10.73 8.47 7,66 7.60 6 10 15 20 MC-24 0 3 6 10 15 MC-25 0 3 6 10 20 30 14.9 50 60 MC-26 0 3 6 10 20 30 40 50 MC-27 0 3 6 10 20 30 40 MC-28 02 (in 1/1) 7.98 6 MC-23 S i%Dl 30 75 100 MC-22 T L1 50 0 3 6 753 7.46 7.29 7.16 12.58 11.54 8.41 7.99 7.72 32,402 32.619 33.103 33.875 33.964 31.430 31.431 31.427 31.499 32.320 32,665 33,1454 33.822 33.859 12.129 22.745 27.658 31.258 12.546 32.744 1.364 1.740 3.241 9,447 .30,092 29.931i- 30.680 33.036 33.205 33.570 33.740 33.807 3.3.863 33.887 29.279 30.728 32.403 32.823 33.3c4 .6i 33.581 7.50 29.898 7.38 33.836 13.98 28.731 13.58. 30.071 31.564 11.58 9.40 32.260 7.70 32.868 7.70 33.14.53 7.55 33.696 7,43 32,Q13 12.77 30.8c6 12.69 31.077 11.64 31.469 .17 '5.52 3.56 1.24 1.40 6.31 6.33 6.31 6.25 4.35 3.76 2.11 2.26 2.16 6.12 5.70 6.31 6.41 6.17 3.70 7.18 7.02 6.66 6.io 3.78 5.76 4.92 3.36 3.30 2.91 2.78 2.52 2.91 2.28 6.63 5.98 4.12 3.93 723 2.62 2.89 2.01 7.00 7.06 6.20 4.91 4.03 2.94 2.59 3.12 6.72 6.70 6.17 Ni .&! 25,26 25.51 25.89 26.54 26.70 23.46 23.47 23,47 23.65 25.07 25.40 26.13 26.47 26.50 8.54 16.93 20.69 23.57 9.5? 25.49 .18 1.36 6,41 23.30 21.90 23.49 25.68 25.93 26.23 26.37 26.43 26.50 26,54 22.07 23,39 25.20 25,60 26.05 26.24 26.47 21.38 22.50 214.,03 24,93 25.67 26,12 26.34 2c.74 23.26 23.44 23.94 S45 ii 1.572 1.945 1.612 .8052 1.0760 .81657 1.5458 4,6705 .5435 4.2514 3.9425 2.115 5.327 2.577 2.705 1.835 3.8671 3.9093 1.8720 2.5414 6.1568 .5463 4.4503 7.3715 32.253 21.025 9.8785 7.2061 29.255 2.7581 59.593 5.4491 16.67 11.19 8.495 --17.82 3.186 6.256 11.10 18.33 7.269 8.552 2.512 1,729 1.108 .7559 .8445 .5935 - - 6.614 7.787 3.155 2.107 1.388 6.092 7.142 4,759 2.709 2,130 1.457 2.502 4.084 4.767 S90 L:1 56.718 57,476 192.40 6.1619 L1..392 2.0989 1.7351 1.7360 2.1361 1.7957 3.5793 7.2308 6.3221 4.3885 2.9934 1.9010 1.8509 1.7232 4.8074 5.5646 4.8106 2.8521 2.0976 1.2184 .99840 1.3017 2.5225 3.8677 3.7919 3.1982 1.7227 1.4583 2.4130 6.7147 7.7418 .2512 4.9923 4.5398 4.7586 2.6971 3.8893 8.6997 6.1188 io;o4i 39.905 26,854 11.809 8.6499 34.831 4.3799 57.848 74.942 63.236 184.80 7.6891 4.7857 2.8772 2.6282 2.9054 3.0507 2.8405 5.0794 8.3236 7.4462 4.9916 3.8518 2.9520 3.0390 2.6879 6.2982 6.8774 5.5709 3.2523 2.8441 2.2101 1.9067 2.4412 3.3874 4,7537 4.9456 3.9001 Tqi 1 (pnuuo) Z riir 8-W 01 0 0 017 0 0 c 9 01 89I o6 Z8 99 09eY IY?I ü'i Z0'II O1'6 11 04i 1L 0 0 1011 O-DW 66 19'3 691 01 66'L 1 0 9c?' L L 96?1 96?I ?'01 9 10I 001 0 o 0j 0 0 9 01 0 1 Iti 9L 101 oi: 0I 0 9 UI 0 0 oi 0 91'L 1iI 176 8' £' 16?C Cc 991 LiC 9O 90' LoY 6'? 912 90? i'o Q9Y?L (v9 0'9 009 o1Y 6' 8YL ;ic 1L csiz o' 6V9 6C9 6I9C 18 69z 8'Z O'1 ;t1 191i 01 0 0 oi r 1iO6 9117'I o1' 661 9L't £' 66 91'9 C9 619 Y9 1O 90' 80 $1c::'9 c1i9 oz 9i'9 I1? L61 o'6? 09 16t1 6Y6 9 96'Ia 991 Ct7 cco 981 9 LI'L I'9I 119L i1 ?7'1 ,9?T t19'o oo 9L Ya 99 0V9? l9' CY o6' L9'I ot7c t0'9 6:8 109 993I 906'6? f1' iC 1'b1 1I?9 96'I? 1Y9 101 69 '9 '1i? oic L1' 9I8' 6' L8Y9 66'c 69c 9?'9 --- 68' I1IY? 9L'1 16' 9,17 C16' 68'Z 08'1 99'1 01'1 --- O'1 c098' 6I -L1 --Olie'? 90' 68I 6C'I 6901' 9o1L L Li6' 1?' $7 ?'ti?9 91 II1 960 L086 s800' 06'1 09C'e I' It6eL't? 999 961i1i'? 1e'i £::s1't1 coco; -?6C 1L' oeY1 11'I 1O1 ?60t7 c190'i1 ?0?' 090' 1i?9 CC'ti o11 0' ó99' I001 ?61C 16'1 1tL 1Lti1 O917 U9 96'( 1e D9Z 0L1?' ?06t7'I 6o? 9'? 061 86I C9 19tL £9 I11? tO1 19(?( LI'L Le7? 8191 9?tiI ot tL 90 186 $7'6 96 ty8'9 Z88 6o1 L8 9f?C 96t' ?9 1' 06S ty --- o68'o L9'9 C' 2'z 990'1 LY9 61C £19 17't7 9O0 69's 9c'cZ OL 160'1 069'CC 09 1'9 £39 £:ii'OI 9 SS 'i 1ô 0 0 IN EQ S 68O 6I0 T1bI L?9ti'I ?9(i' e;o t6Y1 9? 6VL 1Tt 17000'l g69'I LY --" YI ?91L't 9UUT C09?1 9U'1 1j' 1L9'I 6ot I8?1 c9L6L ;o8I 1?L6' jI 091 ai t7916' L90ó1 L6L9' oY1 9L1i 6$i' 69601 .16b6' 25 (continued) Table 1. Z T S J MC-33 76 86 91 96 101 125 150 MC-34 0 3 6 10 20 30 40 50 75 100 125 io MC-35 0 3 6 10 20 31 41 51 76 101 125 150 MC-36 0 3 6 10 20 30 4o 50 75 100 125 iso MC-37 Ni 02 S45 S90 (mi/i) 0 3 6 10 20 o 7.98 8.29 8.44 8.26 8.12 7.93 7,514. 16.02 1.94 15.97 1.93 14.79 11,56 io,iS 9.68 9.12 9.22 8.26 8.o4 14.66 14.61 14.64 14.64 32.859 33.063 33.230 33.354 33.558 33.773 33,920 29.628 29.624 20,625 29.731 32.127 32.394 32.497 32.514 32.618 33.009 33.479 5.31 4.89 4.66 4,29 3.96 3.34 3,18 5.94 5.97 5,97 5.97 6.03 6.97 7.16 7.13 6.42 .4o 32.&i.32 4.10 3.71 6.09 6.06 6.08 6.o8 13.7 32.49 6.143 11.23 10.31 0,97 9.13 8.55 8.34 8.16 14.68 14.67 14.68 14.67 14.14 11.52 10.35 0.62 8.91 9.56 8.55 8.25 14.73 14.72 14.74 14.74 14.71 14.28 32.485 32,540 7.01 7.09 7,14 6.40 5.55 4,53 3.91 6.11 6.11 6.11 6.08 6.40 6.95 7.11 33.81 32.438 32.430 32.432 32,60 32.656 32.993 33.409 13.655 32.396 32.397 32.394 32.395 32.436 32,522 32.5c8 32.566 32.652 33,057 33.503 33.731 32.359 32.361 32.360 32,360 32.362 32.396 .92 6.37 .37 4,22 3.49 6.13 .13 6.13 6.11 6.10 6.36 25.61 25.73 25,84 25.96 26,14 26.34 26.44 21,64 21.66 21,65 21.74 23.85 24.67 24,99 25,08 25.25 2s.6o 26.'6 26.25 24,10 24,10 24.09 24,09 24.41 24.80 25.00 25.07 25,29 25.64 26.00 26.22 24.06 24,06 24.06 24.05 24.20 24.78 25.01 25.14 25.32 25.69 26.04 26,26 24.02 24.02 24.01 24.01 24.02 24.14 1.087 1.485 1.557 1.885 .9144 .6221 .7643 ---1.524 4.592 2.852 1.784 .9909 .8193 1.332 1.202 .8889 .3831 1.798 1.872 1.416 .8247 .9282 1194 1.224 .92'l-4 .7395 .4082 1.211 2.400 1.514 1.150 .84io 1.222 1.186 .9342 .57735 .59018 1.3472 .65623 .84500 .44801 .93317 .98559 .99540 .81265 .86646 .71696 .86917 .86170 .74089 .83125 .80852 .77831 .49483 1.1793 .77770 .98920 .64700 .65299 1.0569 1.1354 1.001 1.1079 .97675 .99940 .70907 .69739 .92916 .79577 .64328 .85926 .90974 .9738 1.4206 .76295 .65542 .6i84 .78268 .314.91 .3168 1.080 2.438 1.167 .9593 .8663s .74149 .0951 .96174 1.3836 1.3378 1.3617 i.05i8 1.5030 1,1314 1.9536 1.8123 1.9103 1.5798 1.7316 1.3146 1.5930 1.2870 1.2757 1.3679 i.56i4 1.4823 1.1454 1.4339 1.3369 1,7342 1,1905 1.1995 1.8386 1.8320 1.7148 1.6559 1.6945 1.7107 1.3815 1.2709 8.4317 1.3860 1.3102 1.4494 2.0303 1.9108 2.100 1.4572 1.3621 1.3812 1.6304 1.8621 1.6855 1.2824 1.2040 1.5917 1,4171 26 Table 1. (continued) Z Stat. MC-37 JJ 40 T S c_ 11,72 50 10.33 9.30 75 8.61 100 8.04 125 150 7.97 0 15.35 MC-38 6 15.36 15.36 10 20 15.32 13.63 30 40 11.88 10.28 50 9.21 75 8.05 100 7.92 125 150 7.71 0 15.39 NC-39 15,37 3 6 15.39 10 15.37 20 15.31 12,90 30 40 11.36 50 10.17 9.42 75 8.85 100 8.38 125 8.17 150 15.28 0 MC-40 15.22 3 15.26 6 15,28 10 15.16 20 10.65 31 10.16 41 9,43 51 8.82 76 8.41 101 8.18 125 7.89 150 i.6o 0 NC-4i 15.58 3 15,56 6 15.39 10 20 15.18 12.25 30 40 10.67 9,96 50 Ni 02 S45 32.17 32,LI.86 32.529 32.883 33.311 33.646 32.138 32.128 32.139 32.129 32.420 32.437 32.493 32.537 32.922 33.431 33.666 32.013 32.019 32.018 32.025 32.040 32.322 32.500 32.534 32.584 32.894 33.454 33.686 32.163 32.158 32.160 32.158 32,169 32.551 32.619 32.574 32.714 33.362 33.634 33.800 32.003 32.001 32.021 32.100 32.125 32.433 32.503 32.506 6.87 7.23 6.56 5.65 4.77 3.68 5.90 5.88 5.92 5.92 6.33 6.75 7.10 6.46 5.37 4,32 3.90 5.98 6.00 5.97 5.98 1,00 6.60 6.94 7.05 6.57 5.68 4.39 3.70 6.02 6.00 6.00 6.02 6.02 7,07 7.01 6.66 6.21 '.54 3.92 3.57 6.oi 6.07 6.01 6.02 6.04 6.86 7.17 7.22 S90 (3) (mi/i) 24.73 24,96 25.16 25.5 25.97 1.5114' .8820 1.245 1.305 1.030 2,24 23.72 -- 23.7fl 23.71 24.29 24,64 24.98 25.18 25.66 26.08 26.29 23.61 23.62 23.61 23,62 23.65 24.36 24.79 25.04 25.28 25.52 26.03 26.24 23,76 23.76 23.75 23.74 23,78 24.95 25.09 25.18 25.38 25,95 26.20 26.37 23.56 23.56 23.58 23.67 23.74 24.57 24.91 25.04 .2403 2.414 1.869 1.829 .9005 1.388 1.295 .9177 .89690 1.2134 1.1387 .98395 .76522 .87578 .68029 .71499 .86164 .83710 .74385 .95686 .78773 .78069 .53051 .62638 .149762 .4755 --.3664 .5174 2.679 2,054 1.549 .7928 1.155 1.435 .9106 --- .5871 3,266 1.17)4 .9286 .8996 1.513 1.019 .8221 .1489 .8110 1.529 .8188 2,888 1.832 1.136 1.068 .91179 1.1340 1.0512 1.0596 90775 .92130 1,4436 1.3574 .92614 1.0570 .81638 1,1511 .95234 .91424 .80113 .96551 .82502 1.1591 1.4216 1.0708 .84838 1.0106 .60623 .76636 .,91609 .84033 1.1129 .88760 1.2092 .97924 .6865i .73258 1.3682 1.5436 1.6159 1.7927 1.3777 1.6805 1.1912 1.3092 1.345)4 1.3138 1.2066 1.5703 1.4322 1.3657 1.1460 1.2558 1.1849 1.5110 1.8131 1.5493 1.5228 1.3777 1.7483 2.4662 2.0781 1.6191 1.9182 1.398? 1.9307 1.11.120 1.4951 1.3366 1.4308 1.3024 1.8765 2.0345 1.5345 1.4692 1.7767 1.4760 1.2719 1.7048 1.4260 1.7830 1.7845 2.3906 1.7506 1.4763 1.3071 27 Table 1. (continued) Z J1 MC-41 ?1C-42 75 100 125 150 0 10 20 30 40 50 75 80 85 90 100 125. 150 NC-43 0 3 6 10 20 30 40 45 50 55 76 100 125 149 Mc-44 0 3 6 10 20 25 30 40 50 75 MC-45 100 0 3 6 T Lcl S 1i 9.08 8.69 8.34 8.00 14.72 14.70 13.05 10.42 9.71 9.36 8.86 8.84 8.60 8.35 8.03 7.93 7.67 12.13 12.14 12.16 12.13 10.22 9.07 8.25 7.85 7.96 8.42 8.23 7.96 7.50 7.17 10.75 10.75 10.77 10.62 7.97 7.80 7.98 8.09 7.95 7.51 7.06 32.696 33.124 33.387 33.697 30.898 30.926 32.170 32.424 32.475 32.510 32.788 32.933 33.125 33.282 33.462 33.702 33.826 31.816 31.819 31.815 31.816 32.061 32.296 32.446 32.526 32.710 32.920 33.295 33.746 33.866 33.921 32,249 32.244 32.244 32.239 02 Ni 6.04 5.25 4.69 3,94 6.22 6.28 6.8 7.17 7.21 6.72 5.78 5.43 5.02 4.68 4.45 3.80 3.75 6.71 6.71 6.74 6.74 6.90 6.64 6.23 6.12 5.50 5.33 4.45 3.58 3.34 3.01 6.50 6.53 6.53 6.50 25.33 25.72 25.99 26.27 22.90 22.93 24.22 24.89 25.06 25.14 25.43 25.55 25.73 25.90 26.09 26.29 26.42 24.12 24.12 24.11 24.12 24.65. 25.01 25.26 25.38 25.51 25.60 25.93 26.32 26.48 26.57 24.69 24.70 24.70 24.72 1.62 1.024 1.070 .5068 3.591 2.601 1.269 .8970 1.091 1.536 1.911 1.820 1.380 .8906 .7445 .4480 .2563 2.305 1.891 1.580 1.575 1.601 1.387 1.241 1.273 .8150 .6236 .5742 .6781 2.624 1,224 1.490 1.369 1.507 1.287 .8228 32.583 5.83 25.5i 32.651 32.824 33.082 33.351 33.790 33.926 5.60 5.30 4.46 3.77 3.27 2.31 25.48 8.91 33.167 8,73 8.30 33.145 33.121 5.22 5.03 4.4 4.28 3.93 3.67 25.72 25.73 .6751 1.262 25.78 1.194 2.98 26.27 10 8.24 33.190 20 8.17 25 8.25 30 7.87 33.265 33.403 33.664 S45 (mi/i) 25.59 25.78 26.01 26.42 26.59 25.84 25.91 26.01 .8495 1.387 2,284 1.775 .57028 .54845 .52631 .55161 1.1086 1.0836 .83041 .5684 .73278 .79224 .57709 1.5555 .69252 .61208 .74194 .67976 .60875 2.3511 2.4356 2.4840 2.8489 1.8668 1.3732 .76175 .67819 .78141 .66866 .69929 .75193 1.5314 .75484 3.1152 2.7175 2.8165 2.7662 .78909 .63325 .77236 .72838 S90 (3) 1.2152 1.3305 1.2858 1.3764 1.6263 1.8451 1.5644 1.1803 1.2883 1.5067 1.1355 1.3607 1.5528 1.2482 1.2331 1.1887 1.1655 2.8269 2.9934 2.8253 3.3850 2.2437 2.1690 1.5163 1.2841 1.6012 1.4721 1.4729 1.4507 2.5022 1.4370 3.5509 3.4001 .77031 .99621 3.3277 3.3245 1.2927 1.2456 1.3422 1.3993 1.4664 1.6945 3.4608 2.5423 2.8211 5.2418 3.6042 3.0498 1.8236 2.6424 2.36Q9 2.6890 2.2287 3.8049 1.5472 1.5687 1.4417 2.4123 28 (continued) Table 1. Z T S (mi/i) Stat. J MC-45 35 3.802 40 45 .843 33.853 33.058 33.175 33.175 33.311 33.558 !1c-46 MC-47 MC-48 MC-149 7.55 7,42 7.39 0 9.17 8.92 3 8.32 6 8.56 10 8.60 20 7.85 30 7.65 140 9.18 0 9.18 3. 9.12 6 10 8.95 20 7.97 30 7.79 40 7.71 9.30 0 9,53 3 6 9.13 8.82 10 20 8.07 7.74 30 7.62 140 7.49 50 10.03 0 10.04 3 6 10 20 30 40 MC-60 0 3 6 10 20 30 40 50 MC-51 0 3 6 10 20 30 40 MC-52 0 2 5 9 9,140 8.84 8.62 8.50 7.67 11.86 8.93 10.26 7.95 7.73 7.55 7.43 7.32 11.43 11.08 10.35 9.89 7.84 7.57 7.41 11.87 11.88 10.33 10.03 33.723 33.771 33.368 33.376 33,392 33.451 33.653 33.727 33.767 32.991 32,887 33.061 33.332 33.565 33.726 33.798 33.829 33.067 33.070 33.104 33.228 33.441 33.573 33.707 33.143 33,147 33.120 33.124 2.51 2.38 2.40 5.61 4.99 4.18 4,37 4.16 2.69 2,38 5.22 5.16 26.42 5.148 25.141 26,147 26,49 25.58 25.73 25.82 2.89 26.08 26.32 26.38 25.82 25.94 5.11 25.87 5.00 25.914 2.92 26.25 2,50 26.33 2.37 26.37 5.35 25.51 5.38 25,61 4.70 25.86 3.18 26.16 2.37 26.33 2.21 26.141 1.87 26.45 5.76 '.82 5.47 5.13 4.46 3.99 25.145 25.46 25,60 25,78 25.98 26.10 26.33 2'.19 25.29 2r,47 2c.93 26.16 26.35 26,45 3.884 2.67 9.06 8.93 7.56 3.78 3.14 2.86 2.36 2.06 26,1 9.19 25.31 9.17 2.38 7.66 25.50 C.J 6.65 2.46 1.97 '6.140 1.61 2(.50 33.176 33.126 33.109 33.140 7.30 7.13 7,59 2,45 6.63 25.52 33.1+96 33,706 33.815 33.877 33.198 33.191 33,178 33.202 33.665 33.775 S45 Ni 02 S90 j .9644 .5970 2.209 1.746 1.282 1.380 1.550 .8172 --.7949 .9157 1.290 1.761 .9028 .6561. 2.8036 4.0580 3.9697 3.5732 3.0955 3.3464 2.5798 3.0972 2.7591 3.0901 4.8038 5.7827 4.7657 4.4290 3.5367 4.8452 5.2754 3.061 2.589 2.528 1.730 1.316 .8596 .6659 .7230 2.115 2.114 1.422 1.096 1.512, 1.8140 2.409 2.994 1.808 1.381 i.oi14 .8109 i.14414 1.999 1.377 2.642 i.ii4 1.042 --- 2.981 1,302 2.523 2.4727 3.1165 2.7165 2.2288 2.1849 2.5265 5.1508 3.1185 3,37914. 3.1705 3.1553 3.3998 3.9Q81 1.7778 4.7926 6.6068. 4.8687 1.5154 1.3705 .98859 1.0023 1.9616 6.6532 6.5680 7.1209 6,1292 1.6225 1.8307 2.6444 6.00i6 4.2739 6.3556 5.1232 4.6452 5.6452 6.6340 4,7347 4.3911 3,4527 3.6544 5.4724 4.1708 4.4724 7.5824 6.6125 6.1539 5.3048 5.0165 6.2376 7.0554 3.9678 3.0838 4.0490 3.8552 3.2562 3.4077 3.5809 7.4803 4.2966 3,7514 4.4777 4.1078 14.2645 4.9361 24542 7.3743 6.8176 6,4585 2,123 2.0373 1.7196 1.9504 2.8742 9.0619 8.0804 8.2337 6,6612 2.5328 3.0398 3.9727 8.8671 5.1149 6.7211 5.6806 6Z iqL t ZDW (panut;uoz) Z .1. tF t5T 08' 61 6z 't O1i't 6si 0 9 01 L ?41'OI Lz'OI 6c'e 31'B 0 69'L 99'L 01 917'L 0? IN S 88'? 19? 0'Z 141'9? 9'1 841'9? 09'I z'9 19°? 81'9 ZZ'? ?9?'I 41c1' L8 L?'c'? 0C9'I 606'? 6L°41 966'? 41?'1 1.'? 116'I e.0'9? 141J'1 09(' 16c9'41 0Y 418Y 841g'c L? ?.'9? 609'CC ?9'1 09' c1'? 4141'9? 416'1 0?C'6? 01'9 C411? 1410E o61 41C'6? t.O9 941'I? I6srC t7?1' 9 61i1 91L'6? 411'9 9.1Z 0'9 01 99,C? 6?oC 41c'L 9C2'IC 0? 9'0T 9?C'? £1L 9L'1? LY1 go' c1419' 6' o ci.o 11'? Y9 ct' 90Z6' 041 11b' 0L41? 9?'9 9Z'2 .O'1 0L't 09? 1'1 s76'L L ?1'9? 9O'1 001 e9'L 41L$' z1' ?1 9' Z' 041'9? T0CY 99'? 41'9? 01 81L : 98tiI 11 9 01 0? o ot ?L'?I o?1 69's 0'L iiL 6L oYeL 41 0 69'L 09 ?L 69 001 c1 93W 641 II'L oi ç9 17L'?I 0 ?C'?I 9 6LO1 01 0? 6G'& O 041 0 0 e.9'L ?9/ ç9 19'L 'T1 io1 9 01 0 0 01 LVOI Ili'9 6a'o 119 0??1 90L 1471 61'e. 1?Z 1'9 6zS L0 O09'? ?LL'z LO?C 41L?' irC o' 18? 7eY 99" 99'3 16 Lt' c9'6 9-1- L' 8°L t2'C OL'L 96'ti 0t 17L'Z? 1L'?? C? LL'? 86'li? ?'? $7? 9Y2 098?C j?8'i7 99? L96'? 6it7 9Y.? 0??E 8Z11 41oc'c 99Y 'L1? 0419? ??6' £L2? O9' 61 06S ty 99'1 609°T 106'? 69418 6941'1 041'? 9L9' ?1?L'I 9419'? tT 0 0 SI'S (T '9Z 9'9 ?9??, 8I i93 ii 41961 oL?L'41 61?o'c c099'C 3L'41 9'1 91 1?9'T 9641C'? 8941'1 ?C19'I 11?9'? 9?cO'( 99O°? 6oY? ?16'1 411'1 910'? 1C6Z'? 99C6'? eL91'? ?9Y1 (9i.'z ?1(?'I 99C66' z9ç' 919' ?4199'T i6otYi ?141'1 ç9T 419996' cct79'I t1166 9109'1 C96419 9C1 69'? 9L0L' 41000? 4168'1 91961 61'? 6o'C C1i' ?961'$ 90aC1 ti9?0'll OliliI 19L?' ICt11 II7CI 81?'I 6?1s 08?0'I 6°1 410611 z4116ó' 10?91 ti'1 9C91 911'1 L6 Y 9C -; ?1?21 96410'I 611i 9LO'? Cr? £99'l 00'1 9i70'? 6899'I ?919'I oiYi 1o6'1 19rY? 0109' 19C? 6?4i? 9Lo'41 9199c 99Y9 tL'9 6'41? Ls71' OOYt7 1Ol9' 1oo 9'41 91'? i I6gVz 6' £9c1 $' 0O'9? L0YI 8o6 9L?Y1 O9 18L1 61 6600'T ?I'C 0C9? --- 9?81'I cOLLI $1'!. tiL6'C L 6t'z 9S9 i1'9 ?'9 L'9 9L°Z o6' 9Z9 1 '1 9t9 9' i60 6' d90'I r'T 699's 9L1i ti909 L9O0 lilieYli I1L t2P9 6°L LCIYt 6C1'? 0c01 0011 99L 16'1 30 I I [S%ol 46°N \\I 20 ) I 'I I I : Jf 24 32 45°N . I 31 I! I I / /J' I I / I I -r // // / I! // / 3 32 I 26 44°N 28/ / / :.°.; 30 //./:* I I I I 4;:.: I; / Figure 3. Salinity distribution on the sea surface. I 31 I OL. 13(45)xK5z (rn-sir)' [1 SI. S / S S . /°ORT . zo /. / 0 In C.JI Figure 4. Scattering particle distribution on the sea surface. 32 L$%oI i°N 32 3' 29 AOM / 30 .'.-.-, 28 26 / ////////// I / /7'/7)./ '4 .. RT 44°N 32 - 33 .;. ;' j'.<4:;l / N- '.D It) /:: Figure 5. Salinity distribution on the 3m surface. CJ 33 I I I I3(45)xIO2(m-str 4.0 50iWPORT S Figure 6. Scattering particle distribution on the 3m surface. 34 I . . (. N 32 . 31 n__/ 31 )X 32 . 0 Figure 7. Salinity distribution on the lOm surface. 33 .R. 35 I I (45)xId2(m-Str1' 46°N . . Ii /4.t° . S 45°N / . I / I S 4 5 5d4 IL 44°N :: Figure 8. Scattering particle distribution on the lOm surface. 1 S S R II I S 32.5 , , S , S S; 33 RT S S S S / ( S :;., S S 0 ID l.() 7' 0 (7 t Figure 9. Salinity distribution on the 2Orn surface. £I 37 (45)Kr (m-str 4°N 4°N ..: WPORT .7 44°N , ) 3.0 / / )). / .2.0 1 0 F.- 0 w 0 / 1' U) Figure 10. Scattering particle distribution on the Z0m surface. 38 S S S ,, 5; o4!1 S -o ? S S IS . I 1 ,. / / -, S / I5°N I S S S . I 32.5 32.5 wpo/i / S / ' 33.0 \ S I S I S'S I S I I 33.5 , I 4401, / ,32.5- ;. Figure U. Salinity distribution on the 30m surface. 3.0 507.0 I I I3(45)xIO (rn-str ///$ !O .: /1 4°N / I / V / ( I r0 44°N I I I I.OZL9 Figure 12. Scattering particle distribution on the 30m surface. . - . a,' 20n.m. I A 40n.m. -,' - - - 25 50 = :\. I.Iii c 7 100 I 125 1s (%)1 150 Figure 13. Salinity distribution on Section I. 0 20n.m. IV1.f.J I IVI-'It I 40n.m. I 2. 25 2..7 50 = I- a- w c 100 125 [ 150 Figure 14. Scattering particle distribution on Section I. (5) x jo2 (m-str)1] 'MC-25 20n.m. MC-141 40n.m. I I ° r I MC-6 DB-40 6 ¶:i iT\ HT 7 [Temperature Figure 15. Temperature distribution on Section I. (°c)] 25 50 = I0 LLI 75 100 125 150 Figure 16. Sigma-t distribution on Section I. 40flmIIA('_ lit' IA 20fl.m. flR4fl -I.-- 'I - - 6. - - - - - 7 25 50 I- 4 0 Iii TNiiIIIJ a 75 S 3 100 S 125 [02 (mI/liter)] N 1 5C Figure 17. Oxygen distribution on Section I. MC-12 MC-13 MC-14 110n.m. MC-15 MC-IG zpn.m. 0 25 5O z I0 w c 75 100 125 [S (%o)] 150 Figure 18. Salinity distribution on Section II. Ui MC-12 MC-3 MC-14 I0 B. MC-15 MC-16 un.m. U -I- 25 EEEEEEE 50 I- 0 w c 100 125 t (15) x iO (m-str)] 150[ Figure 19. Scattering particle distribution on Section II. C' MC-2 MC-13 MC-14 I MC-15 un.m. 11.111. I -II MC-.t6 I 25 S. - . 50 0 tLI c \ '. IS 100 125 rnperature (°C)J 1501 Figure 20. Temperature distribution on Section II. MC-12 MC-13 MC-14 MC-16 MC-15 ton.m. 2pn.m. 0 25 5o I0 Lu c 75 100 . '265 i 125 1 5C Figure 21. Sigrna-t distribution on Section II. MC-12 MC-13 MC-4 tim. MC-IS 1w_I Z.On.m. U 25 iitH 50 ii I aLU 75 100 125 [02 (m1/Jter)] 150 Figure 22. Oxygen distribution on Section II. 25 50 = I $ij cD 75 100 125 150 Figure 23. Scattering distribution on Section III. u-I C I On.m. 20 n.m. MC-5 0 MC-4 32 25 - 50 x I0 w ci 100 335 - 125 [S (%)J 150 Figure 24. Salinity distribution on Section III. (B -15 -0 .Yf-.-.'. -2.O 3O _-1.0 .1. -25 -O -'fU S 'vi'--' 1.0 2 0 . S S S S .. I- 0 w S 5.'\ S S S S S I S 5 S . S S S 1 S S S S I (45) X 102 (m-str] 1 Figure 25. Scattering particle on Section IV. U.' t\) L - -10 -? -0 - -iO -40 [1 32 25 50 F- 0 w 75 S 100 125 S S S [S (%o)] 1501 Figure Z6. Salinity distribution on Section IV. a- w 1O( 12 1 5( Figure 27. Scattering particle on Section V. U, 55 RESULTS General Features of the 1968 Summer Columbia River Plume The area distribution of the Columbia River plume observed during the 6806C Cruise is presented in Figures 3 to 10 in terms of salinity and particulate concentration. The Columbia River plume in the summer is characterized by a tongue oflow salinity, high temperature, and high particle concentration extending south or southwest from the river mouth. The orientation of the plume is in agreement with the general seasonal characteristics of the plume, and its simple tongue-like shape clearly indicates the Columbia River as the single source of the fresh water in the region. One method of delineating the plume is to use some character- istic isopleth as a boundary. Budinger et al, (1964) suggested that the 32. 5 ppt isohaline is a suitable boundary for the Columbia River plume. In the vertical section along the plume axis, the isohalines (Figure 11) seem to suggest the 32.0 or 32.25 ppt isohaline may be a better choice of the plume boundary in this case. The salinity vs. depth curve of a station near the plume axis shown in Figure 28 clearly indicates that the boundary between the fresh river effluent and the more saline ocean water is located at approximately ZOm depth, which corresponds to the 32.25 ppt isohaline. The numerical value of the salinity plume boundary may vary from year to year as 56 27 S T. 29 31 33 14 35 I6 I.- 0 w Figure 28. Temperature and salinity vs. depth curves for stations MC-5 and MC-6. 57 flow conditions change. The Columbia River plume as defined by the 32.25 ppt isohaline has a maximum width of about 110 nautical miles and extends south or southwest to about 250 nautical miles from its source near Astoria, Oregon, and is contained within the upper 30m of water. The horizontal plume defined by 32. 25 ppt isohaline can be very closely approximated by the isopleths of 24.0 sigma-t and 15°C temperature in the 3m surface (Figures 29 and 30). The bottom boundary of the plume can also be drawn approximately by the 25. 0 sigma-t and 11 to 12 degrees Centigrade isotherm which correspond closely to the boundary set by salinity. The bottom boundary values of sigma-t and temperature are noted to be different from those of the edge boundary in the 3m surface. This is the result of the heat- ing of the surface water by the solar radiation. The particle concentration analyzed in the same method as the other parameters shows the isopleth of particle concentration along the outer plume boundary in the sea surface, 3 (45) = 1.0 x 10 (m-str)', is in fair agreement with the boundaries set by the other parameters, but with considerable differences along the shore side of the plume (Figure 4). The main reason for the differences ob- served between the particle distribution and the salinity distribution is that the coastal water acts as a disturbing source of particles while the low salinity water has come only from the mouth of the SIGMA- T [1 . N 23 . 0 F.- 24 25 .I2 0 w c,J Figure 29. Sigma-t distribution on the 3m surface. 59 ).HT. TEMPER I5?% .;ç. . 5 S 6 6 / /5 / I //(PT / I . . 0 t 0 IL) cJ Figure 30. Temperature distribution on the 3m surface. Columbia River. The large particle concentration of the coastal water on the shore side of the plume is primarily due to the high biological productivity associated with coastal upwelling, and second- arily due to the sediments disturbed by the water in shallow water. This is due to the nearer proximity of the phytoplankton bloom, relatively larger volume of the phytoplankton source, and more involved process of transport and suspension of denser bottom sediments. Consequently, the particle concentration contrast between the plume and oceanic water on the shoreward edge of the plume decreases as the downstream suspended load decreases and as the effect of the coastal source increases. The axis of the Columbia River plume in 3m depth as defined by the different parameters used is presented in Figure 31. The axes of the plume delineated by the different parameters nearly coincide and the small deviations seem to be almost within the limits of error. The plume axis defined by particle concentration, however, is shorter than that defined by salinity: the tongue-shaped feature of the plume in particle concentration vanishes at about 100 nautical miles from the source (Figures 4 and 6). The Columbia River plume is clearly identified and characterized by the high concentration of particles for about 100 nautical miles downstream from its source in spite of the disturbing effects from the nearshore water along the Oregon coast. 61 $27 46 24 $25 $26 SCATTERING A TEMPERATURE Al o SALINITY ' SIGMA-I 0, Al 45 QUINA hi! A/il 44 43 Figure 31. Columbia River plume axes defined by salinity, temperature, sigma- t, and scattering particle on the 3m surface. 62 In three cross sections, at the river mouth, at about 30 nm. from the river mouth, and at about 60 nm. from the river mouth, the total particle content was checked by the product of the cross-sectional area of the plume defined by 32.25 ppt isobaline times the mean particle concentration. The products for the three cross-sections agree within five percent. The same computations for two more cross-sections further downstream, one at 90 nm and the other 120 nm from the river mouth showed a marked decrease. Since the particle distribution in the last cross-section, the one at 120 nm from the river mouth, shown in Figure 27, unmistakably indicates no plume particles, we may consider the product of the cross-sectional area and the mean particle concentration computed for this section as the value of the ambient water. Subtracting the value of the ambient water from the values of the other cross-sections, the fourth crosssection gave about 30 percent of the first three sections. On the basis of the above estimates, the particle content of the Columbia River plume is a conservative property of the plume water over a distance of 60 nm and this distance corresponds to about ten days if Frederick's (1967) 12 cm/sec surface current is assumed. There is no indication in Figure 14 of a large number of sinking particles in the water below the plume axis about 60 to 90 nm downstream from the river mouth. The salinity distribution in the 10 and 20 meters (Figures 7 and 9) shows a low salinity center 63 located about 120 nm downstream from the river mouth. This ex- tends the salinity plume along its axis in the downstream direction. An examination of the particle distribution indicates that the low salinity center mentioned above does not correspond with high particle concentration. This fact suggests that the portion of the plume water indicated by the low salinity center has gone through a complicated history instead of a simple form of the plume shown in the present data. If this is the case, then the particles contained in the water at the low salinity center had been lost for some time and consequently the water is considerably older than that at the terminus of the tongue-shaped plume defined by the particle concentration. The suspended particles in the plume water will slowly sink down below the plume water, and in time particle concentration becomes non-conservative property. It was shown to be conservative over a distance of 60 nm and a period of ten days. If a steady de- crease of concentration is assumed, the particle concentration should approximately be conservative for another three to five times 60 nm and ten days, that is another 180 to 300 nm and 30 to 50 days. Because of the seasonal variations of the wind system, the plume delineated herein is in the transition from winter to summer plume, and the plume will extend further south to southwest in time. During the spring, before the northerly wind becomes predominant, the Columbia River plume was flowing northward and a separate cell 64 of plume water was found at about 50 nautical miles north of the Columbia River mouth during 8 to 24 May, 1961 (Budinger et al., 1964). As the summer wind system developed, the pool was carried downstream by the wind as a body of effluent. A surface salinity distribution observed during the period of June 7 to 19, 1962, which was seasonally about two weeks earlier than the observation herein, is shown in Figure 32 (Budinger et al., 1964). It has a separate low salinity cell located to the offshore side of the present fresh plume axis, but it does not contribute to the extension of the present plume length. When this '62 plume is compared with that of the '68 plume, it is easy to see that the '68 plume could have resulted from a movement of the low salinity center from the '62 position in the down- stream direction. An estimate of the drifting speed of such a pool was made using monthly mean wind at 45°N, 125°W taken from daily surface weather map (Fisher, 1969), and geostrophic current at the sea surface computed from hydrographic data taken from both the NH-line and the DB-line each month. The method of computing drift is given by Budinger et al, (1964), which provides an estimate of the predicted plume position by adding the geostrophic current and Ekman transport. The result of computation are listed in Table 2. All the values of transport (drift) are north-south component. As Budinger et al. (1964) noted, the use of monthly mean wind instead of the actual wind in wind stress computation may introduce a 65 66 considerable error, and the error tends to cause the result too small, It can be seen from Table 2 that the monthly total drift in April and June is about one half of that in May. The total computed drift in May and June is about the same as the distance from the river mouth to the terminus of the plume determined by particle distribution, The lowest value of drift in April may be interpreted as the period when the pool was stagnant. Table 2. Meridional components of geostrophic current and Ekman trans port. April May 0.8578 4.5246 June v-component of geo- strophic current, Vg (cm/sec) Monthly mean wind (m/sec), u v Ekman transport (gm/(cm-sec)) x 10 2 - 3,04 4,34 45. 7515 Ekman transport velocity, V (cm/sec) Total velocity, Vg + Ve (cm/sec) Monthly total drift, nautical miles - 1,44 2,14 10. 5495 2,4193 - 0,645 4.985 9,2084 1. 525 0,3515 0.307 2.4828 4.8761 2.7263 33,332 68.2103 38.135 67 A thick layer of particle maximum is found on the offshore side of the present plume axis below 30m depth (Figure Z3). Its thickness increases down to deeper water as the distance from the plume axis toward offshore direction increases. Thickness of this layer is about 50m at MC-4 and about 90m at MC-3. Flows The plume region, as described earlier, reveals a weak southward surface flow. During the summer season a persistent wind from the north contributes to a more steady southward surface current. The plume orientation clearly results from these current and wind conditions, This northerly wind also causes an upwelling phenomena along the coast (Smith, 1964), The surface water under the northerly wind stress is transported offshore and water from the deeper layer upwells near the coast to replenish the transported water. The coastal upwelling is clearly indicated by the upward slope of the isopleths of temperature, salinity, density, and particulate concentration toward the shore in the vertical section across the plume (Figures 18 to Z8). It is also noted by the band of cold water along the coast. One of such distribution of cold temperature is shown in Figure 30. In a previous paper (Pak, Beardsley and Smith), an offshore subsurface flow was discussed in connection with a temperature inversion and a tongue of high particle concentration under upwelling conditions. In the above discussion, the temperature in- version and the corresponding scatterance maximum and minimum transmittance was interpreted as the result of a flow along the slanted permanent pycnocline. The water which flows along the perma- nent pycnocline was formed from the dense upwelled water, modi- fied by the solar heating, mixed with the warmer and less saline surface water, and supplemented with particles of phytoplankton products. The upwelled water originating from a depth below the permanent pycnocline undergoes these modifying processes, and the resulting water becomes similar in density to that at the bottom of the permanent pycnocline. As this water is carried offshore by the northerly wind, it tends to flow along the slanted pycnocline since it is denser than its neighboring water. Another subsurface offshore flow is likely to occur from a consideration of the continuity of upwelling and the existence of the plume. The process of the formation of this source water is entirely analogous to that of the offshore flow along the permanent pycno- dine except that the final density of the offshore flow is smaller than that of the permanent pycnocline. Thus the water does not sink to the permanent pycnocline, but stays near the surface until it meets with the Columbia River plume. Then it dives under the plume. The pronounced pycnocline at the bottom of the plume, sloping downward offshore, acts like a barrier for the denser water moving offshore. The particle concentration plotted against temperature on Section II is presented in Figure 33, showing that a tongue of water of high particle concentration is associated with 11°C temperature. The 11°C isotherm in Figure 20 corresponds to the particle maximum located at the lower part of the plume in Figure 19. This layer is also associated with an oxygen maximum slightly below the particle maximum. The difference in the depth between the particle and oxygen maximum may partly be explained by the fact that the oxygen maximum is controlled by both the nutrients associated with the particle maximum and an optimum amount of sunlight. The particle distribution to the north of the Columbia River mouth at the 30m surface (Figure 12) under the southward flowing surface layer, indicates that the large particles which sank quickly from the river plume are flowing northward, which conforms with the current measurements of Collins et al. (1968). The evidence of the northward flow in the deep layer is also found in the distribution of sediments originating from the Columbia River. Gross and Nelson (1958), by means of a radioactive tracer method, found that MC-13 oc __j MC-14 89 MC-I6 MC-15 1099 10 -r 15 / 4 Li' 2 5 -.1 Figure 33. Temperature vs. scattering particle on Section II. C 71 Columbia River originated sediments are distributed to the north and west of the Columbia River mouth, Duncan et al, (1968) showed that the Group I clay minerals (Figure 34), which were derived from the lower Columbia and Snake River sub-basins are found primarily north and west of the Columbia River mouth. In addition to the coastal upwelling driven by the wind system, it is also conceivable that the entrainment process suggested by Tully (1958) exists, In that case upwelling of the deep water occurs under the fast moving plume especially around the river mouth. The entrainment of deep water by fast moving surface water seems to be analogous to the upwelling of deep water resulting from the offshore transport of surface water driven by the wind except for the difference in the driving force, The present data near the river mouth shows the upwelling effects but wind driven coastal upwelling cannot be dif- ferentiated from that by the entrainment, The offshoreward subsurface flows discussed above may be performing an important role of biological interest. The existence of the Columbia River plume is essentially blocking any direct transport of upwelled nutrients into the surface layer, and the region offshore side of the Columbia River plume could not have a high nutrient supply without the subsurface offshore flow discussed above. The distribution of the upwelled nutrients beyond the Columbia River plume must be ascribed to the subsurface offshore flows along the 72 460 1260 128° 130° IY 124° 4 COL1$JS/A c\. 46° GROUPI /' I ° wI °ASTORIA ; is I .' GROJP2 rAcCADIA CHANNL (GROUP /1 '- o ' 440 "J/ 4. 'k., -'' I I:) p. .1 ' .', C) I 'CAPE OLANCO ROGUE RIvER ° 1/ C2_L_______.t 130° ORE. / 128° Figure 34. Distribution of Holocene clay-mineral groups. i 124° 73 permanent pycnocline and the pycnocline under the plume. Model Plume The Columbia River effluent is the major source of light scattering particles in the plume region. A model has been developed to describe the general pattern of paths and processes by which the river particles are distributed to ocean water masses. It was assumed that the bottom slope of the plume region is such that the plume water has little influence from the bottom sediment. Thus it is valid when the plume is in deep water immediately off the river mouth. Particles with a wide range of sizes, densities, and indices of refraction are carried down the estuary by the Columbia River. The high density particles that were carried by the river effluent will sink rapidly into deep water below the plume within a few miles from the river mouth. These particles are permanently lost from the river plume. The less dense particles tend to stay in the plume for a long time. The sinking of these light particles is so slow that they may be considered as conserved in the plume. For such a tendency of conservativeness in the plume, the concentration of the less dense particles serve as an indicator of the plume position and mixing processes. 74 While the light particles are kept in the plume, they settle internally to form one or two layers of particle maximum within the plume. In general, the bottom of plumes are identified by a marked density gradient, which is associated with a large salinity gradient. One layer of particle maximum occurs at this level. Because of solar radiation a thermocline is eventually created even if there were no thermocline across the lower boundary of the effluent leaving the estuary. If the vertical gradients of salinity and tempera- ture are located at two separate levels, then two layers of particle maxima will be observed as shown in Figures 35 and 36. As the plume continues its flow and spreading, the solar radiation maintains the thermocline despite mixing and diffusion, but the salinity gradient weakens continuously. Thus the particle maximum associated with the halocline eventually disappears as the plume diffuses and only one layer of particle maximum remains. -- bU 0 100 /20 /60 NM 25 32.2 ISOALINE 50 I aw c 100 125 150 Figure 35. Plume model on a section along the plume axis. -J 'SI 'In 0 -- MV DV 32,5 ISOHAIjNE 25 ;50 0 w 75 100 125 150 -.1 Figure 36. Plume model on a section across the plume axis. 0' 77 DISCUSSION The Columbia River effluent had the simple form of a plume extending south to southwest under the persistent north to north- easterly wind as described in the previous section. Because of the coastal upwelling along the Oregon and California coasts, the plume was kept away from the coast. The horizontal spreading of the plume is clear evidence of horizontal diffusion, but the vertical diffusion is limited by the presence of the vertical gradient of the density at the bottom of the plume. Tully (1958) and Budinger et al. (1964) concluded that the vertical mixing of the fresh water plume takes place in the form of entrainment of the sea water below the plume into the fresh water. Thus the vertical exchange is only in one way, that is upward transport of heavy sea water into the plume water, and as a result the plume tends to maintain its lower boundary at the same level or lift upward, and glides over the heavy sea water resulting in horizontal spreading. The Columbia River effluent carries particles of all sizes. The large particles quickly sink into the ocean water below the stratified plume within a few miles from the river mouth. These large particles, after they leave the plume water, keep sinking and are also carried away by the flow of deep water. The water below rI1 the plume is generally slow and tends to flow in the opposite direction from the surface flow due to the upwelling caused by the wind and entrainment effect resulting in a restriction of the spreading of these large particles. In the case of the Columbia River, the deep water flows northward with an onshore component, and the large particles are carried northward within a few miles from the coast (Figure 12). The small particles are contained in the plume and carried along with the plume. The plume is oriented towards the south to southwest responding to the prevailing wind. The plume is bounded by cold and saline water upwelled from deep water on the coast side, and cold and saline ocean water on the oceanic side. The length of the plume depicted in the horizontal plane is approximately 100 nautical miles on the 3m surface. Using the sur- face velocity of 12 cm/sec determined by Chromium activity (Frederick, 1967), the time required for the plume to reach a point 100 nautical miles downstream from the river mouth is about 20 days. On the basis of conservation of particle content to the extent discussed in the previous section, the length of the model plume should not be limited to that of the present data. It is more likely to extend beyond ZOO nautical miles (about three times the length of the present plume axis) under a steady wind condition. This figure is, of course, a first approximation since it will vary with the cb3rac- teristics of the effluent, stability structure, and extent of mixing. 79 The particle concentration in the Columbia River plume region can conveniently be described by three distinctive layers: the first and second layers in the plume water itself, and the third layer in the water below the plume. The Columbia River effluent was warmer than the ambient sea water (Figure 30). This plume water was heated by the solar radia- tion at the surface. The net result was a strong vertical tempera- ture gradient, the thermocline, at the lower part of the plume water. The entrainment of cold sea water and the solar radiation heating at the surface of the plume water cause a strong thermocline and also a strong halocline, The particles contained in the plume water showed a tendency to settle down slowly within the plume water. As they settled down, they were trapped at the level where the vertical density gradient was a maximum. Two layers of particle maximum, the first and second layers, were observed at the maximum density gradient levels which are associated with the maximum stability (Figures 37 and 38), The Brunt Vàisàlâ frequency is used as the stability para- meter. The two layers of particle maxima were not observed at the edge of the plume and near the river mouth of the plume (Figures 39 and 40). Along the edges, mixing is extensive so that the halo- dine becomes quite weak and the first layer does not exist. In the vicinity of the river mouth, the upwelling ofdeep water due to the 2 0 Ui FigUre 37. Scatt ng particle profile at I' -2 -I = I aLLI Figure 39. Profilesof stability and scattering particles at MC-25, near the river mouth. -2 -I LU 50 Ni] M Figure 40. Profiles of stability and scattering particles at MC-33, at the edge of the plume. wind and also the entrainment causes the river effluent to be kept in the upper 10 to 15 meters depth, so that the temperature and salinity gradients are unable to be separated. The third layer is difficult to simplify in the model, because it is not uniformly distributed and its cause may be diverse too. It could have been formed by the process(es) of (1) sinking of the parti- des from the plume when the plume stagnated for a long period of time, 2) erosion of particles trapped at the bottom of the plume by the subsurface offshore flow, 3) transport of particles from the surface layer by the subsurface offshore flow, and 4) in situ biological production. The particles in the third layer could have been derived by any one of the processes introduced above, or any combinations. The sinking of particles will take place all the time but their quantitative treatment is difficult. The subsurface offshore flow is evident from the temperature inversion (Figure 20), bulges in particle concentra- tionfrom shore to offshore in 20 and 30 meters surfaces (Figures 10 and 12), and also the correlation of temperature and particle con- centration (Figure 33), A super-saturated oxygen concentration layer is found under the plume axis, implying that the photosynthetic production is active. At the stations, MC-5 and MC-15, the third layers is found as a 30 meters thick layer and centered at about 55m depth. The stability of the water column (Figure 41) is high at 75 to 85 -2 N -I 7/ 1/ ;50 I- 0 w I. Figure 41. o MC-15 L MC-5 Stability profiles at MC-5 and MC-15. 90 meters, and a low stability exists at 55m depth at MC-5. This must be an indication of the fact that the sinking is not the major process responsible for the third layer. The particulate substances that the Columbia River introduces into the oceanic region off the Oregon coast during the summer season under the predominant northerly wind may be considered under the following three processes: 1) the heavy particles sinking from the plume water immediately off the river mouth, Z) erosion of particles (particles settled to the bottom of the plume) by the subsurface offshore flow along the bottom of the plume, and 3) the sinking of small particles which have been contained in the plume water. By the first process, large particles are introduced into the oceanic region but confined within a narrow zone along the coast due to their high rate of sinking and the deep water circulation northward with onshore component. These particles must be studied more closely since there were too few stations near the river mouth. The second process is a direct consequence of the upwelling and its downstream (offshore) extent is not known, but it may be re- lated to the intensity of the upwelling. From Figures 10 and 12, it can be noted that the offshore subsurface flow is associated with the bulges of particle concentration, and this implies that the subsurface offshore flow is patchy instead of uniform along the coast. This subsurface flow should be closely related with water of high biological productivity since it consists of upwelled water and passes through lighted depths of water. This flow will pick up some particles as it moves along the bottom of the plume water. The third process is the process which was ignored in the model plume. The Columbia River plume data suggest that the plume could be traced a much longer distance by the particle concen- tration later in the season, The model tacitly assumes that the small particles are nearly conserved over the length of the plume. Thus particles will eventually sink from the plume water which is distributed over a large area, approximately over ZOO nautical miles downstream, and the plume is acting as a broad plane source of particles. The study of the Columbia River plume was motivated by the need of understanding the process by which particles carried by the river effluent are distributed to the ocean water. The application of the optical method to the oceanographic problem is directly related with this knowledge. The model describes the basic process of de- livering particles: 1) large particles sink immediately within a few miles of the river mouth, and Z) small particles are contained in the plume water, which spreads out, responding to the general circulation of the sea surface, over the ocean water as a layer of about 30m thick. The river effluent, mainly because of its density relative to the ocean water, effectively converts a point source of particles, river mouth, into a surface source of particles. The size of this surface is a function of spreading causes, i.e., currents and wind field, and residence time of the particles in the plume water, This residence time is estimated as 30 to 50 days. It is useful to consider the results of Ketchum and Shonting (1958) in light of the present model. In order to show that the parti- des found in the Cariaco Trench originate in the Orinoco River it is necessary to establish: 1) that the plume reaches the trench; 2) that the particles are retained in the plume until the trench is reached; and 3) that the density structure of the plume changes in the vicinity of the trench so that the particles can fall to the observed depth of 100 to 220 meters. In the absence of data on the temperature and salinity of the water at and upstream to the Cariaco Trench it is impossible to establish either the path of the plume or the stability of the water column, The particle distribution in the Cariaco Trench does not show any indication of river plume in the surface layer. The time of travel between the river mouth and trench appears long in comparison to the residence time of particles in the Columbia River plume. Thus none of the conditions required is shown to be true for the Orinoco- Cariaco system. Since the water over the trench must pass over a sill with the maximum depth of 24 meters immediately at the upstream edge of I the trench, it seems much simpler to attribute the observed particle distribution to the topographic effect (Jerlov, 1968), BIBLIOGRAPHY Anderson, C. C. 1964. The seasonal and geographic distribution of primary productivity off the Washington and Oregon coasts. Limnology and Oceanography 9:284-302. Beardsley, C. F., Jr. 1966. The polarization of the near asympto- tic light field in sea water. Ph.D. thesis. Cambridge, Massachusetts Institute of Technology. 119 numb. leaves. Budinger, T. F., L. K. Coachman and C. A. Barnes. 1964. Columbia River effluent in the northeast Pacific Ocean, 1961, 1962: Selected aspects of physical oceanography. Seattle, University of Washington, Dept. of Oceanography. 'ISp. (Technical Report no. 99) Burt, W. V. and B. McAlister. 1959. Recent studies in the hydrography of Oregon estuaries. Research Briefs of the Fish Commission of Oregon 7: 14-27. Burt, W. V. and B. Wyatt. 1964. Drift bottle observations of the Davidson Current off Oregon. In: Studies on oceanography, ed. by Kozo Yoshida. Tokyo, Japan, University of Tokyo. p. 156-165. Cissell, M. C. 1969. Chemical features of the Columbia River plume off Oregon. Master's thesis. Corvallis, Oregon State University. 45 numb, leaves. Collins, C. A. 1964. Structure and kinematics of the permanent oceanic front off the Oregon coast. Master's thesis. Corvallis, Oregon State University. 53 numb, leaves. Collins, C. A., C. N. K. Mooers, M. R. Stevenson, R. L. Smith and J, C. Pattullo. 1968. Direct current measurements in the frontal zone of a coastal upwelling region. Journal of the Oceanographical Society of Japan. (In press) Duncan, J, R., L. D. KulmandG. B. Griggs. 1968. Clay- mineral composition of late Pleistocene and Holocene sediments of Cascadia Basin, Northeastern Pacific Ocean. (Submitted to the Journal of Geology) Duxbury, A. C. 1965. The union of the Columbia River and the Pacific Ocean, In: Ocean Science and Ocean Engineering, 91 1965: Transactions of the Joint Conference of the Marine Technology Society and American Society of Limnology and Oceanography, 1965. Washington, D. C. p. 914-922. Fisher, C. W. 1969. A statistical study of winds and sea water temperature during Oregon coastal upwellings. Master's thesis, Corvallis, Oregon State University. 67 numb. leaves. Frederick, L. C. 1967. Dispersion of the Columbia River plume based on radioactivity measurements. Ph.D. thesis. Corvallis, Oregon State University. 134 numb, leaves. Gross, M. G. and J. L. Nelson. 1958. Sediment movement of the continental shelf near Washington and Oregon. Science 154: 879 -881. Hickson, R. E. and F. W. Rodolf. 1951. History of the Columbia River jetties. In: Proceedings of the First Conference on Coastal Engineering, Long Beach, 1950. Berkeley, Council on Wave Research. p. 283-298. Jerlov, N. G. 1953a. Influence of suspended and dissolved matter on the transparency of sea water. Tellus 5: 306-307. Jerlov, N. G. 1953b. Particle distribution in the ocean. Reports of the Swedish Deep-Sea Expedition, 1947-1948, ed. by Hans Petterson. Vol. 3. Physics and chemistry. Goteborg. Elanders Boktryckeri Aktiebolag. p. 73-9 7. In: Jerlov, N. G. 1955, The particulate matter in the sea as determined by means of the Tyndall meter. Tellus 7:218-225. Jerlov, N. G. 1958, Distribution of suspended material in the Adriatic Sea. Archivio di Oceanografia e Limnologia 11:227250. Jerlov, N. G. 1959. Maxima in the vertical distribution of particles in the sea. Deep-Sea Research 5: 178-184. Jerlov, N. G. 1968. Optical oceanography. Elsevier, Amsterdam. l94p. Jerlov, N. G. and B. Kullenberg. 1953. The Tyndall effect of uniform minerogenic suspensions. Tellus 5: 306-307. 92 Ketchum, B. H. and D. H. Shonting. 1958. Optical studies of particulate matter in the sea. Woods Hole, Massachusetts. 28p. (Woods Hole Oceanographic Institute. Reference no. 58-15) Morse, B. A. and N. McGary. 1965. Graphic representation of the salinity distribution near the Columbia River mouth. In: Ocean Science and Ocean Engineering, 1965: Transactions of the Joint Conference of the Marine Technology Society and American Society of Limnology and Oceanography, 1965. Washington, D. C. p. 923-942. Neal, V. T. 1965. A calculation of flushing times and pollution distribution for the Columbia River estuary. Ph.D. thesis. Corvallis, Oregon State University. 82 numb. leaves. Osterberg, C., N, Cutshall and J. T. Cronin. 1965. Chromium51 as a radioactive tracer of Columbia River water at sea. Science 150: 1585-1587, Osterberg, C., J. Pattullo and W. Pearcy. 1964. Zinc-65 in euphausiids as related to Columbia River water off the Oregon coast. Limnology and Oceanography 9:249-257. Pak, H., G. F. Beardsley, Jr. and R. L. Smith. 1969. An optical and hydrographic study of a temperature inversion off Oregon during upwelling. (Submitted to the Journal of Geophysical Research) Park, K. 1966. Columbia River plume identification by specific alkalinity. Lirnnology and Oceanography 2: 118-120. Rosenburg, D. H. 1962. Characteristics and distribution of water masses off the Oregon coast. Master's thesis. Corvallis, Oregon State University. 45 numb. leaves. Sasaki, T., N. Okami, G. Oshiba and S. Watanabe. 1962. Studies on suspended particles in deep sea water. Scientific papers of the Institute of Physical and Chemical Research (Tokyo) 56: 77-83. Smith, R. L. 1964. An investigation of upwelling along the Oregon coast. Ph.D. thesis. Corvallis, Oregon State University. 83 numb, leaves. Spilhaus, A. F. 1965. Observation of light scattering in sea water. Ph.D. thesis. Cambridge, Massachusetts Institute of Technology. 24Z numb. leaves, Stefanson, U. and F. A. Richards, 1963, Process contributing to the nutrient distribution of the Columbia River and the Strait of Juan de Fuca, Limnology and Oceanography 8:394-410. Tully, J. P. 1958, On structure, entrainment, and transport in estuarian embayments. Journal of Marine Research 17: 5Z3535, U. S. Bureau of Reclamation. 1947, The Columbia River: A comprehensive report on the development of the water resources of the Columbia River Basin. Washington, D. C. 393p. APPENDICES 94 APPENDIX I COLUMBIA RIVER AND ITS ESTUARY The Columbia River is carrying the bulk of fresh water into the northeastern part of the Pacific Ocean through its estuary located at the border of Oregon and Washington States (Figure 42). Its total length is approximately 1220 statute miles (Hickson and Rodolf, 1951). The drainage basin (U,S Bureau of Reclamation, 1947),which covers 670, 000 Km2 with 85 percent of this area within the United States, includes nearly all of Idaho, most of Washington, Oregon and western Montana, and small areas in Wyoming, Nevada and Utah. The watershed of the Columbia River constitutes about seven percent of the nation's area. There is considerable seasonal variation in the mass transport of the Columbia River. Maximum discharge occurs during May to July due to melting snow at the head waters, whereas the maxima for the small coastal streams south to the Rogue River normally occurs during the wet period from November through February. Average flow in the period of maximum and minimum discharge is about 660, 000 and 70, 000 cubic feet per second (Hickson and Rodolf, 1951). Total flow represents approximately 14 percent of the total annual discharge from continental United States. Seasonal variation in precpitation shows more precipitation in 95 Tzo N 150W Figure 42. Columbia River basin. IIo winter than in summer, A quick run-off of winter rain on the west side of the Cascade Range controls the coastal stream discharges to create a seasonal variation opposite to that of the Columbia River. There is a winter peak flow in the Columbia River depending on coastal precipitation (Duxbury, 1965). The winter discharge may deviate considerably from its mean value, Using Pritchard's classification (1955), the Columbia River estuary at Astoria, Oregon, belongs to type B (partially mixed type) during high discharge period and type D (well mixed) during low river period (Neal, 1965), Upstream the estuary is type B except for high river flow when it becomes type A (Stratified). The tide at the river mouth of the estuary has a mean range of 6. 5 feet and the tide itself is the typical mixed semi-diurnal tide of Northeastern Pacific Ocean (Neal, 1965). The salinity intrusion ranges from ZO to 15 nautical miles upstream from the river mouth depending on whether type B or type D conditions exist (Burt and McAlister, 1959), Further physical and hydrological details of the Columbia River were discussed by Budinger et al, (1964) and Neal (1965), 97 APPENDIX II REVIEW OF REGIONAL OCEANOGRAPHIC CONDITIONS OFF THE OREGON-WASHINGTON COAST The oceanic region off the Oregon and Washington coast is characterized by a weak and poorly defined current, the Eastern boundary current, The North Pacific west wind drift diverges into northern and southern branches, The northern branch feeds into a gyre in the Gulf of Alaska, and the southern branch forms a broad California Current, Seasonal patterns in wind produce distinctive seasonal varia- tions in near-shore current systems. During October and through March or April, south or southwest winds prevail and result in a northerly surface current, called Davidson Current (Burt and Wyatt, 1964), and during the rest of the year, north to northwest winds prevail to cause coastal upwelling (Smith, 1964). In the Northeast Pacific Ocean, precipitation and fresh water drainage from adjacent land masses exceeds the evaporation so that the area is a region of net dilution (Budinger et al., 1964), The oceanic region subject to the influence of the Columbia River plume is contained within 40 to 50 degrees North, and 1Z4 to 132 degrees West (Budinger et al., 1964). Rosenburg (1962), Collins (1964), Pattullo and Denner (1965), and others discussed the water mass characteristics of the region in detail. The water mass above lOOm depth, according to them, con- sists largely of Subarctic water mixed with a small amount of Pacific Equatorial water. The Columbia River plume shows a large seasonal variation in its position due to the prevailing surface current which is driven by the prevailing wind, During the summer, prevailing wind drives the surface water southward with offshore component causing deep water to upwell. A band of high salinity and low temperature water along the coast in summer is the direct consequence of the upwelling. A zone exists parallel to the coast between upwelled water near shore and non-upwelled water offshore. This zone is referred to as a front because there exist a large density, temperature, and salinity gradients across this zone (Collins, 1964). The Columbia River effluent is the major source of fresh water drainage in the Northeast Pacific Ocean, and is the primary cause of the low salinity water near the shore of Oregon. Yet, during some period of the year, primarily the winter, the Columbia River effluent becomes less distinguishable from that of the other coastal streams once it becomes part of the marine environment. During the summer, the Columbia River plume is often kept intact as a shallow lens of water, over the dense sea water due to the calm sea and large river discharge (Budinger et al., 1964). Tully (1958), and Budinger et al. (1964) explained that the mixing occurs in such a way that the salty sea water mixes vertically upward into the plume, and little fresh water is lost through the halocline. Buoyancy of fresh water keeps it above the sea water. Tully (1958) attributed this phenomena to the lower coefficient of vertical eddy viscosity near the pycnocline than in the water above it. Budinger et al. (1964) delineated the Columbia River plume by 3Z. 5 ppt isohaline, which they found consistently corresponds to 30 to 40 meters depth in the vertical and about 760 Km downstream during late summer. During the winter, the plume turns northward and lies closely along the Washington coast. High run-off from the coastal streams and low Columbia River discharge in the winter complicate the Columbia River plume determination (Budinger et al., 1964; and Duxbury, 1965). The Columbia River plume has been studied by salinity (Budinger et al., 1964; Duxbury, 1965; Morse and McGary, 1965, and others), by plant nutrients (Stefanson and Richards, 1963), Chlorophyl (Anderson, 1964), Alkalinity (Park, 1966), and by radio- active tracers (Osterberg, 1964; Osterberg, 1965; and Frederick, 1967). 100 APPENDIX III BRICE PHOENIX LIGHT SCATTERING PHOTOMETER Introduction The B rice Phoenix light scattering photometer, which was used to measure the intensity of scattered light, is a laboratory type instrument, It measures the intensity of light scattered from water samples contained in the Pyrex-glass scattering cell and placed in the path of the light beam. Thus it requires samples taken by means of the sampling device. The scattering intensity is measured at angles between 300 and 1350 measured from the direction of the beam, and the limits are imposed by the geometry of the system. The volume scattering function is deduced from the intensity by formula (1). The light source is provided by an 85 watt mercury arc lamp, and the output of the photomultiplier detector is recorded on a re- corder. In order to keep the input to the photomultiplier detector in the linear range of the system, a set of four neutral density filters are used in the light source to control the intensity of the light source. Interference filters are used to control the wavelength of the light beam. The details of the instrument are described by Spilhaus (1965) and they are not repeated here. 101 Calibration of the B rice Phoenix Light Scattering Photometer The calibration of the Brice Phoenix light scattering photometer was done basia1ly by the working standard method of Tomimatsu and Palmer (1963), but by an entirely dependent derivation of the relations. The volume scattering function defined in equation (1) can be expressed in terms of radiance and recorder output voltage. The radiant intensity falling on the detector in the direction of 0 is, J(0) = N SA S (5) where N S is scattered radiance and A 5 is the area of the scattering volume defined by the distance between the scattering volume and the detector, and the solid angle £2D. The radiance, N, N, and ND representing the incident, scattered, and detected radiance respectively, is a function of £2, and d, assuming the time dependence is negligible. The voltage output recorded, V0, may be expressed by V D (0) = k NsD A % Tg (1 - R) (6) where k is a constant conversion factor (volts/flux), T and R are transmissivity and reflectivity of the Pyrex glass scattering cell, From equation (1) and (5), the scattered radiance is expressed by N = 1(0) N00 £2 T (1 - R) g (7) 102 recalling that the incident irradiance, H = N £2 00 , and the scattering volume, V = A 1(0), where 1(0) is the path of sight. The path of sight is t sinO, when t is the width of the light beam. Then equation (6) with equation (7) substituted in for N becomes VD(e) = k (0)l(0)N ooDDg £2 A T 2(1 £2 The voltage output at 0 0, - R)2 (8) VD (0), is written as 2 VD(0) = kuN £2 £2 A T ooDDg (1 - R)2 where a is the working standard constant. The ratio of VD(e) to VD(0) is VD(0) p(e)l(o) a (6) t a sine (9) The ratio of voltage outputs, Vw and V op is V V w op kN2a2A 00 D D kN2T2A oo oDD a fo where Vw and V op are voltage outputs when the working standard and opal standard were placed in the beam respectively, T is the transmissivity of the opal standard. 103 The working standard constant, a, is V a V w T op (10) 0 From equation (8), the volume scattering function is written by = VD(0) V T VD(0) V t op sinO Thus the calibration constant K is expressed by T Y V T op (1Z) t is provided with the instrument by the manufacturer, and t can easily be determined. Operational Procedures The operational procedure includes the sampling of water, operation of the B rice Phoenix scattering photometer, and reduction of the recorded data into the volume scattering function. Water samples were drawn from the desired depth by Nansenbottles hung on regular hydro-wire. The inside of the Nansen-bottles were coated with teflon. The water samples were transferred to plastic nutrient bottles. The nutrient bottles were rinsed carefully 104 to avoid contamination. Since there are always some possibilities of contamination from the transferring of the samples to nutrient bottles, a direct transfer of samples from the Nansen-bottle to the scattering cell is desirable. The estimated time of storage in the nutrient bottle ranges from ten to thirty minutes. According to Spilbaus (1965), the error that might occur by the storage of less than one hour is negligible. The operation of the Brice Phoenix light scattering photometer starts with warming up the light source and photomultiplier. The power was put on as soon as the instrument is installed, and left on for the entire cruise. On the power source a voltage regulator was used to prevent any fluctuation of voltage. It was convenient to make a log on the recorder chart before the measurement about the cruise, station, date, and other things that might be needed later on. A semi-hexagonal pyrex-glass scattering cell was used, and this cell enabled measurement of the scattered light at 45, 90, and 135 degrees. The scattering cell was cleaned before the first sta- tion and clean double distilled water was filled in, and also whenever the instrument was idle the scattering cell was filled with the same double distilled water, After the sample was poured into the scattering cell, the cell was seated on the cell base in the light tight 1 (' 1. U. compartment. The alignment of the scattering cell was checked by watching the reflected light beam from the scattering cell back to the slit through which the light beam emanates. The cap of the light tight compartment was closed. At this time another log for the sample in the instrument was made. This log included the depth of the water sample, color of the light, time of measurement, etc. The 00 reading was made first. Using the neutral density fil- ters attached near the light source, the output was kept near 4 to 5 my. The output decreases as the angle increases, and the neutral density filters become unnecessary. The output of open ocean water at 90° is usually less than 4 my without using any neutral density fil- ter. As the output is recorded, the angle of measurement and neutral density filters used must be recorded. The output often shows some fluctuations. The record was made long enough, some- times as long as one minute, to record the minimum reading. The higher values are from the motes, which are very difficult to treat uniformly, and the effects of the motes are avoided by taking the minimum readings for all the measurements. The data read from the chart was processed by a CDC3300 computer to deduce the volume scattering functions corresponding to angles of measurements. The formula for the volume scattering function is given in equation (7). The data processing includes 1) take account of the neutral density filters used, Z) normalize to the NO), 3) take account of the scattering volume, 4) take the calibration constant into account, and 5) make correction for reflections. These processes are discussed by Spilhaus (1965) and the complete computer program is presented here without repeating explanations on steps. Error Analysis Spilhaus (1965) determined the precision of measurements of the B rice Phoenix light scatterometer from an experimental measurement made on pairs of samples drawn simultaneously. The measure- ment itself could not be made simultaneously. By the deviation of J(0) from its mean at each angle, the standard error was ± 0. 034. He also analyzed the error caused by the aging of the sample by repeating the measurement of the same sample with various storage time intervals. He did not find a pattern of changes as a function of time. Beardsley (1966) discussed the precision of the same instru- ment. He found a standard deviation of four percent for the drift of the electro-optical system by taking time average of a large number of one second period readings. He also found that the repeatability of the calibration can be determined with a precision of two 107 TPil 310') S1 prAt SCAT 4 C"N 'W F? ,I iFPS1J (10) N 12/?3/ 1. 1 (1 RO) , IF7 (1 k'l) N(. 3(1 Mo I , (1) ,F4 ( 3) .AS (1 MO) ,CAS 1 Cl1, (F (1) T1 , 3 , (F2 (11 , Ri') ,csr9lF9 od 13 F1AT (12F,.l) PFr 14t , (F 4 ( j iF+ C Fl I , 1 I ),C'I. C 1) fl g ( ) I = I , 1) (CAL (I AMI)4 ,(AC.11)A=l ,1) 105 F"lAT (3F14,7) ,K1,'?,K')K,K1,K4,15,KA Fr,l4AT (M(T4,1() RFAIi 1112, 1112 PFAO 33). in 310 rrir (110) 1010 P'r 1)1,LAo!l)A,Tp.)EPT1.TTM,nATF.STATT J.CCUTS ,S:pVFw l')l F'1A1 (Tl.J X,T1 ,1X.44,IX,A4,1X,AR,lX,A7.1X,A5,1 ILA1"°A) s0fl,c00,fl1 1 Sot CrINJE 2FA 102 1'2,PCI,P(1 ) *.'A4) ,F'JFl (1) ,!IF?(3 I ,NF3(1) ,NF4(1) , (P(ç) ,NF I (K) ,NE?H') FO1AT (F3.0,9C1X.F3.0.4T1)) PTNT 1O2), 100 FQ?lAT (1k ,lOX.TM.1l,Tl .1 x,i1 ,1 X.A4,1K,44,IX,AM,) ,A7.1 g,A5,l x,?,o IR) PI1=(P(1)_PCt)*F4CT(F1(LAI)A).kF)(1)*FACT(F?(LA11l),NF2(1))*FACT( IFIO AMOA) ,htF3(1) I C F4 CI AMC)AI ,PJF'+ (1) A5((<)=((P(K)_PiT)*FACT(Fl(LAMr1eNF1(K))*FtCT(F2(L,l)A).Nfd((c))*FA 1rT(r3(LAMrlA),NF1(K))*vAcT(F4(,ArA0A).jF4CK))*CAL(LAnA)*sIf(MLlINIDfl 1) / U' 1) MR CITTtJIIF DZ 99 K=KS,Kf,K6 =J*K,lR0 TF(l(.L).9O) 12,13 12 CAS (K)4S(K).076*AS CL) r, TC 100 13 CAS (K) .4% (K) _.0lk*AS (1) 10(1 cSJrTN1IE 99 (ONTIM'E RAT=C45 (45) /CAS (J36) RATT=CAS(45) /CAS(Q0) PQTNT 3OS,CAS(4),CASCQ0).CAS(11S,,AT.PAYT 305 FPHAT (14X,HAS(4S),F14.4,1X.RkCAS(90)s,l4.4,1X,'kCAS(l35),F1 l4.4,? (3X,F14.4) /1 PU'IrH 336, Ifl,LMflA, IP,DFPTH,TTMF,flAT,ST4T13lhCRUiSF 316 FPkAT(I1°,lX,Tl ,1X,Tl,lX.44,1 X,A4,1(,AR.lX,A7,' ,AS) 2I('.IrH 333,Tn,CAS4,CAS9°,C65135 333 FORMAT (1X,TlO,IX, 46S=,F14.4,t*,3k9°=,Fl4.'4,lX,'4-411=,Fl.4) TflTf)1 ( TC 1))0 500 F"Jfl Fl(IrTIN FACT(F,NF FACT:l ,0 TF(NF.E(.1)FACTF ENO p e r C e nt. To test the repeatability of the instrument, an experiment was made with a sample prepared by adding 10.5 micron diameter Latax spheres into cleau sea water. The sea water was prepared by filtering through 0.8 micron Millipore filters many times. The cleanliness of this filtered water was checked by scattering measurements aLId also by Coulter-Counter measurements. The number of Latax spheres added was determined by the Coulter-Counter method. The sample prepared in this way was measured by the Brice Phoenix light scatterometer at angles of 0, 45, 90, and 135 degrees using blue and green light. Two days later, the same procedure was re- peated by a different person. The results are presented in Table 3. Table 3. Results of error analysis. Color (xlO Blue 0.0408 0,0354 0.0040 B=A 0. 0180 N2 N1 x 100 C5 D (xlO ) 0. 0129 45 90 135 N1 B 0.0176 45 90 135 Green A= A5 0 0.44% 4.98% 14.4% 1,28% 2,43% 9.7 % 0.0062 0.0045 0.0144 0.0125 0.0014 0. 0063 0.15% 1. 73% 5,08% 0.45% 0.85% 3.39% C = Standard Deviation D = (Stand. Dev,/p(0)1)x 100 109 The errors are larger at the larger angles than at 45 degrees. These errors include that of the Coulter-Counter and all the opera- tional errors such as electro-optical drift, cleanliness of the scat- tering cell, human error, etc. The experiments were made aboard the R/V Yaquina during a cruise on the open ocean. The errors due to the storage time of samples discussed by Spilhaus (1965) will be much smaller in this work since samples are measured much more quickly by measuring at only three angles, while Spilhaus took readings at 5 degree intervals from 30 to 135 degrees. The recording pen often drifts to give a wide range of value. This is due to the motes of the particles in the scattering volume, especially large particles like swimming zooplanktons. It is diffi- cult to account for the effects of this non-homogenous state. We considered the scattering from a sample of water as a sum of basic scattering and anomalous scattering from a few foreign particles (from large particles that cause the large variations). The effects of such anomalous scattering are eliminated by taking long records, as long as one minute, and taking the minimum value. Another set of experiments was made to determine whether or not the Nansen-bottles contaminated the water samples as compared to newer plastic sampling bottles, and the experimental errors. The experiment included sampling and light scattering 110 measurements. Seven Teflon coated Nansen-bottles were tested against four Niskin bottles, one Van Dorn bottle, and two NI0 bottles. The Nansen-bottles and plastic bottles were placed in alternating order on the hydro-wire with two meters spacing. The choice of each individual bottle was made randomly. The bottles were lowered to Z50 meters depth, well below the thermocline, and water samples were taken, The scattering measurements at 450 were made in random order until each sample was measured twice. The result of this experiment shows that the Nansen-bottles are no different from the newer plastic bottles, and the mean error of the same sample and the mean of the same type bottles were approximately five percent each.