AN ABSTRACT OF THE THESIS OF
Richard James DeRycke
for the M. S.
Date thesis is presented
/(
(Name)
(Degree)
in
Oceanography
(Major)
Title AN INVESTIGATION OF EVAPORATION FROM THE OCEAN
OFF TH.E OREGON COAST, AND FROM YAQUINA BAY, OREGON
Abstract approved
Redacted for Privacy
/(Major Professor)
A weather station was established on the dock of the Oregon State
University Marine Science Center, Yaquina Bay, O:Legon. A total of
197
weather observations was made from 30 June
ber
1966,
1966
to 23 Septem-
with emphasis on the determination of the rate of evapora-
tion from an evaporation pan and from atmometers.
Sources of observational error were investigated and corrections
applied as necessary. The daily variation in evaporation was determined.
The correlation between wind, vapor pressure, and evapora-
tion was found. Atmometers were used to estimate the evaporation
from the surface of Yaquina Bay, and the possibility of using atmo-
meters at sea was investigated.
AN INVESTIGATION OF EVAPORATION FROM THE OCEAN OFF
THE OREGON COAST, AND FROM YAQUINA BAY, OREGON
by
RICHARD JAMES DERYCKE
A THESIS
submitted to
OREGON STATE UNIVERSITY
in partial fulfillment of
the requirements for the
degree of
MASTER OF SCIENCE
June 1967
APPROVED:
Redacted for Privacy
Prolèssor of Oceanography
In Charge of Major
Redacted for Privacy
Chairman of Department of Oceanography
Redacted for Privacy
Date thesis is presented
1/
Typed by Marcia Ten Fyck
ACKNOWLEDGEMENT
I wish to thank Dr. June G. Pattullo for her help and guidance
throughout this project. My appreciation also goes to Mrs. Susan
J. Borden for her help with problems on some of my computer
programs, and to Mr. Duane Frdman at the Marine Science Center
in Newport, Oregon, for his help in running salinities and in setting
up the atmometers.
Special thanks goes o my wife, Dennis, for her help in data
processing and in typing up the rough drafts of the thesis.
TABLE OF CONTENTS
Page
INTRODUCTION
EQUIPMENT USED
OBSERVATIONAL PROCEDURE AND DATA ANALYSIS
Observational Procedure
Determination and Correction of Observational Error
Data Analysis
DISCUSSION OF RESULTS
The Evaporation Day
Evaporation Correlated to Wind Speed
Evaporation as a Function of Height Above the Sea Surface
Daily Evaporation Rate
Estimation of Sea Surface Evaporation Using Atmometers
Equation of Evaporation
COMPARISONS WITH OTHER STUDIES
Reduction of Pan Evaporation to Sea Surface Evaporation
Average Daily Sea Surface Evaporation
Equation of Evaporation
1
4
11
11
14
18
20
20
25
25
27
27
31
34
34
34
35
SUMMARY
36
BIBLIOGRAPHY
38
APPENDICES
40
LIST OF FIGURES
Figure
Page
1
Location of the weather station.
5
2
Arrangement of atmometer and burette.
8
3
Average hourly temperature of the air, bay surface
water, evaporation pan water, and average incoming
radiation (Q).
12a
Schematic representation of the tilt of the surface
water in the pan caused by a northwest wind.
16
Error produced by the wind blowing over the water
surface of the evaporation pan. Some points signify
more than one observation.
16
Average hourly vapor pressure of pan water, bay
water and air. The average hourly relative humidity
is also shown.
21
4
5
6
7
8
9
Average hourly cloud cover, pan evaporation and
wind velocity.
Normal surface air pressure (in mb) over the Northeast Pacific Ocean, based on U. S. Weather Bureau
22
Normal Weather Chart (August).
24
Average pan evaporation observed at various wind
speeds.
24
10
Atmometer evaporation rate (E
11
Correlation between atmometer evaporation (E)
and pan evaporation (E).
12
Estimated sea surface evaporation as a function of
at5.5rn100%.
a
)
vs height. Rate
the sea surface water vapor pressure (e), air
vapor pressure (ea), and wind speed (kt).
26
28
32
LIST OF TABLES
Page
Table
1
A comparison of the constants of evaporation as
determined by the author, Rohwer (1931), and
Kohier (1954).
35
A1' INVESTIGATION OF EVAPORATION FROM THE OCEAN OFF
THE OREGON COAST, AND FROM YAQUINA BAY, OREGON
INTRODUCTION
The purpose of this study has been to investigate various methods
of estimating evaporation from the surface of the sea and to estimate
the evaporation from the sea off the Oregon coast. It is not possible,
at present, to determine directly the amount of evaporation from the
sea surface, as no technique for doing this has yet been devised.
Two indirect methods of determining evaporation from the sea surface have been used. One method involves the use of heat budget
computations and another uses evaporation pans.
The heat budget method assumes that the temperature of the
ocean in the region is unchanging and that there is a balance at the
sea surface between solar radiation, heat conduction, back radiation
and evaporative heat transfer. Sverdrup, Johnson, and Fleming
(1942) have shown how the heat budget method may be used to esti-
mate evaporation from the sea surface. Because it is not possible
to determine solar radiatior, back radiation, and heat conduction
with a great deal of accuracy, evaporation determined using the heat
budget method is considered somewhat inaccurate.
Another method of determining evaporation from the sea is to
measure evaporation (E) fron an evaporation pan at a known elevation (Z) above the sea surface. Sea surface evaporation is then
estimated from empirical relationships. This method is used in
this study.
Evaporation measurements were made in an evaporation pan
above the surface of Yaquina Bay, Oregon. As Yaquina Bay is only
a short distance from the Pacific Ocean (Figure 1), it is assumed
that the physical factors affecting evaporation in the bay are not very
different from those of the open ocean within a few miles of the bay.
The physical fac:tors assumed to be nearly the same are: wind
velocity, air vapor pressure, sea water vapor pressure, and air
turbulence.
One of the major problems in such a study is that an evaporation
pan cannot be expected to evaporate at the same rate as the bay surface below it. Several attempts were made in this study to make the
pan's evaporative characteristics closer approximations to the evaporative characteristics of the bay. An attempt has been made to correct pan evaporation rates for the errors introduced by having the
pan above the bay surface.
The possibility of using atmorneters for evaporation measurernents at sea was investigated.
The atmometer evaporates water
from a porous porcelain sphere and can be used to measure the
evaporativity of the atmosphere.
Evaporation was first determined in an evaporation pan, and,
using atrnometers, sea surface evaporation was estimated.
3
Observational errors were determined as part of the study.
The
relationship between evaporation and environmental factors was estimated and an eqLlation was written expressing the relationship.
A
comparison was made between the results of this study and the results
of other studies in this field.
Evaporation from the sea has been studied by Jacobs (1951),
Wast (as discussed by Defant, 1961), Sverdrup (1951), and many
others. Most of their studies involved the use of evaporation pans
or heat budget computations.
Laevastu (1960) has summarized the work of many individuals on
the subject of evaporation. He also developed a method for correct_
ing evaporation rates for the effect of the change of wind velocity with
height above the sea surface.
Rohwer (1931) and Kohier (1954) studied evaporation from evap-
oration pans on land.
They developed equations expressing evapor-
ation as a function of wind velocity and the difference between pan
water vapor pressure and air vapor pressure. They also investigated many of the problems associated with the use of evaporation
pans.
Lane (1965) studied the climate and heat exchange at the airsea interface off the Oregon coast. The factors affecting evaporation
in the area were estimated as part of this study.
4
EQUIPMENT USED
A small weather station was operated from 30 June, 1965 to 23
September, 1965 on the end of the dock at the Oregon State University
Marine Science Laboratory near Newport, Oregon (Figure 1). This
location was chosen to give the best available approximation to marme atmospheric conditions as they exist off the Oregon coast.
It
was assumed that the marine air flow was not greatly affected by the
small amount of land between the weather station and the ocean.
There were no significant obstructions to the air flow in the immediate vicinity of the evaporation pan.
The equipment used at the weather station consisted mainly of
standard U. S. Weather Bureau instruments. The following is a
description of the various items of equipment.
(1)
Evaporation pan
An evaporation pan of four foot diameter was used. It was
placed on a platform 5. 5 m above mean high water. A stilling
well was placed in the pan. (Because the base of the stilling
well was made of steel, it tended to rust very rapidly in the salt
water. The stilling well base was painted twice to prevent
rusting; this effort met with a moderate degree of success.
For this reason no evaporation data were gathered on the periods
7 July to 9 July and 24 July to 29 July. Even after the stilling
IpA*
LJ
o_______
z
4
w
o
0
WEATHER STATION
o
a
naut. me
NEWPORT
U-
0
4
a.
YAQUINA
BAY
TOLEDO
'2
Figure 1. Locatioo of the weather station.
well base had been painted some rust accrued o it and on the
bottom of the evaporation pan.) A hook gage calibrated in cm
was used to measure the water level in the evaporation pan.
It could be read with an accuracy of 0. 002 cm.
(2) Rain gage
A standard eight-inch non-recording rain gage was mounted
near the evaporation pan.
The measuring stick was calibrated
in inches, and tenths.
(3)
Sling psychrometer
A standard sling psychrometer was used to obtain the wet
and dry bulb air temperatures. These were estimated to be
accurate to 0. 1°C. The relative humidity was determined from
these readings.
(4) Hygrothermograph
A hygrothermograph was placed near the platform on which
the evaporation pan was mounted to obtain continuous records
of temperature and humidity.
(5)
Thermometer
A. laboratory thermometer was used to determine the temp-
erature of the bay surface water and the temperature of the water
in
the evaporation pan. It had been calibrated by the author and
had an accuracy of 0. 1°C.
7
(6) Anemometer
Wind speed and direction were determined by the use of a
hand-held anemometer and a wind vane located on the dock.
The
velocity was read in knots and direction in points. The instru-
ment was calibrated against velocities indicated by two other
anemometers and found to be accurate within approximately 1 kt.
(7) .Atmometers
The atrnometers used on this study each consisted of a
porous porcelain sphere 5 cm in diameter, on a lacquered stem
(Figure 2). In use, a hose was connected to a 50 ml burette and
to the neck of the atrnometer. The volume of water evaporated
was measured (in ml) directly on the burette. It should be noted
that the atmometer gives a volumetric measure of evaporation
while evaporation pan measurements yield a linear amount of
evaporation.
The atmometers were intercalibrated three times during
the project to see if they all operated at the same rate, They
were operated at the same elevation during intercalibration.
The difference of evaporation rate was insignificant when all
atmometers were operated under exactly the same conditions.
It was thought that the height of the water column in the burette
would affect the rate of evaporation from the atmometer. Tests
were run to see if the idea was true.
The results showed that
- ATMOMETER
BURETTE LACQUERED STEM
RUBBER HOSE
Figure 2. Arrangement of atmometer and burette.
the height of the water column exerted an insignificant effect
upon the evaporation rate for those heights of the water column
used in this study.
The atmometer must only be handled by holding the laquered
neck (Livingston, 1935). Dust, or possibly in this case salt, can
decrease its efficiency and accuracy. For this reason the atmo-
meters were washed after each exposure to the air. Only distilled
water can be used in them as dissolved solids in the water will clog
the pores. They also required several hours of soaking and opera-
tion before they were operating efficiently and accurately, as evidenced by comparison of the evaporation rates between atmometers
and by the repeatability of the readings.
After intercalibration, the atrnometers were operated simultaneously at several different levels above the water surface to determine the change of evaporation rate as a function of height above
the sea surface. At least one atmometer was always operated adjacent to the evaporation pan in order to correlate pan evaporation
rate with atmometer evaporation. The lowest atmometer was placed
ç'n a small raft and was about one meter above the water surface.
The others were placed at 1. 5, 3. 0, and 5. 5 m above mean high
water.
The atrnon-ieters were changed to a new position (e. g. the
highest was moved to the lowest position and the lowest to the second
highest position, etc. ) for each new time series. The rotation of
10
the atmometers was done to decrease any errors arising from minor
differences in evaporation rates between atmorrieters.
11
OBSERVATIONAL PROCEDURE AND DATA ANALYSIS
Observational Procedure
The weather observations were taken by the author in accordance with the U. S. Weather Bureau manual, !nlnstructions for Clirna-
tological Observers (U. S. Weather Bureau, 1962). The observations
were taken on three or four days each week during the summer
months of 1965. Weather observations were generally taken at two
to four hour intervals between 0800 and 2400 (Pacific Daylight Time).
Atmometer observations were taken at more frequent intervals be-.
cause they appeared to be much more sensitive to atmospheric
changes than the evaporation pan. However, an atmometer observa-
tion was usually made each time a weather observation was made.
As a rule, atmometer observations were not made more than a few
hours after dark as they became quite erratic as soon as a small
amount of dew appeared on the spherical surface.
Each observation consisted of the following:
The height of the water in the pan was measured five times and
the mean of the five measurements was determined.
The type of clouds and the amount of cloud cover (in tenths)
were recorded,
The wet and dry bulb temperature of the air was taken 5. 0 m
above mean high water. The temperature of the water in the
12
evaporation pan and the temperature of the surface water of the bay
was also determined.
The level of the water in the atmometer burettes was determined
during those times that the atmometers were operating.
Observations were made of the present weather conditions, e.
g.
raining, cloudy, clearing, fog.
Usually the evaporatLon pan was emptied and refilled at least
once a day. This served several purposes. As the evaporation pan
was intended to serve as a simulation of bay surface conditions, it
was necessary to maintain in the pan as nearly as possible, the
temperature and salinity of the bay. An increase of salinity was ex-
pected, and this was observed. As a rule, the salinity never increased more than four parts per thousand above the bay salinity.
Although this is a large change in salinity by oceanographic standards,
such a rise in salinity has an insignificant effect upon evaporation
rates
The temperature of the pan water always tended to be higher
than the bay water (Figure 3).
This was due almost entirely to the
effects of solar heating of the water. Thus the temperature of the
pan water tended to rise and fall each day due to the sunlight
mci-
dent upon the pan. The average incoming radiation (Q) as deter-
mined by Maughan (1965) during June and July (1965), is shown in
Figure 3 and its relationship to pan temperature is apparent. It is
N
U)
I-
pan
(Q5). radiation incoming average and water,
evaporation water, surface bay air, the of temperature hourly Average
s) (hour
2324 22 2021
19 18 I?
16
15
14 13
12
3.
Figure
time
ii
10
0809 07 040506 0203 0001
'I
TT
0.2
S 0.4
12
'3
'C
14
0
I5
0.8
1
'
16
1.0
3
0
7
LC
18
1.4
19
13
interesting to note that the average temperature of the bay surface
water did rise slightly each day, but not nearly as much as did the
pan water temperatqre.
Three attempts were made to control the pan temperature. A
shallow aluminum pan was fabricated and the evaporation pan was
placed in it.
The evaporation pan was held about Z. 5 cm above the
bottom of the outer pan by thin boards which allowed a free passage
of water over most of the bottom surface of the evaporation pan. Ice
was then placed in the outer pan.
It was hoped that the ice would at
least lower the pan water temperature a few degrees. Unfortunately,
the solar radiation was great enough to overshadow any significant
cooling effects of the ice.
Another attempt was made to lower the evaporation pan water
temperature by adding ice within the water in the evaporation pan.
This was done by freezing water in tin cans and then placing the
"ice cubes' in the pan.
This method also failed to lower the pan
water temperature significantly as a temporary drop of only about
0.
50
was noted
The evaporation pan was emptied and refilled on many days in
the afternoon. The water with which the pan was refilled was taken
out of the bay and had the same temperature as the bay. However,
the temperature of the recently refilled evaporation pan water immediately began to rise and had a temperature of well above bay
water temperature abotit an hour after refilling. This attempt to
14
control the temperature of the pan water was also unsuccessful.
None of the attempts to lower the water temperature of the
evaporation pan was successful. However, it is thought that the
effect of this temperature diference can be reduced appreciably
through the use of an empirically determined equation.
It was necessary to refill the atmometer burettes periodically,
usually once a day. On some days with high evaporation rates it
was necessary to refill the burettes as often as every four hours.
Determination and Correction of Observational Error
Early in the study it became evident that the water level as
measured in the pan was changing elevation more erratically than
should be expected from evaporation alone.
It was found that
occasionally the water level rose even on days when there was no
precipitation. This suggested that the wind stress and the thermal
expansion of the water might be causing the rises in the water
elevation as determined on the hook gage.
Investigation showed that the amount of thermal expansion of
the water could lead to measurable changes in level when there was
a
change of 2° to
30
in the water temperature between observations.
Therefore it was decided to apply a correction, using coefficients
of thermal expansion of sea water as given by Sverdrup, Johnson,
and Fleming (1942).
This correction was made in the computer
15
program using the equation:
zH= cxDxT
(1)
Where H is the change In water elevation, C is the coefficient of
thermal expansion, D is the water depth in the pan, and
T
is the
difference in temperature between successive observations. The correction normally was not more than 0. 1 mm for about a 1. 0° temperature change and about 0. 2 mm for a 3.
00
temperature change.
Variations in wind speed seemed to have a greater effect than
those of thermal expansion. Apparently the lip of the pan acted in
such
face.
a
way as to cause a pressure differential across the water surThis caused the water on the windward side to rise and that
on the leeward side to fall (Figure 4). The effect was measured by
placing an obstacle in the path of the wind so that there was no wind
over the pan surface. A water height observation was made with the
obstruction in place and then another was immediately made with the
wind blowing freely over the surface. The difference between the
two revealed the "error" for that wind velocity. Thirty-five such
observations were made for a northwest wind at various wind veloci-
ties (Figure 5). A southwest wind had no observable effect. Winds
from other directions were very unusual and were not used to deter-
mine error. An equation expressing the effect was derived using two
linear regression equations. One straight line was assumed from
5 kt to 17 kt and another from 17. 1 to 35 kt. This was done by visual
16
wind direction
i1e11
Figure 4. Schematic representation of the tilt of the surface
water in the pan caused by a northwest wind.
2.0
I
5
E
!
i.o
I..
0
0.5
0.0
!
0
L.'
5
I
tO
I
IS
I
20
25
wind velocity (kt.)
I
I
30
Figure 5. Error produced by the wind blowing over the water
surface of the evaporation pan. Some points signify
more than one observation.
17
estimate of the break in slope and the correlation coefficients obtamed indicated that it was a good estimate.
Van Dorn (1954) found
a similar increase in slope of the surface water of a small pond due
to an increase in wind speed. The loss of accuracy at higher wind
velocities is obvious from the figure, but few wind velocities of these
magnitudes were observed during this study.
The equation for the 5 to 17 kt range was:
B
0. 059W - 0.279,
(2)
with a correlation coefficient of 0. 80 and an estimated variance of
0. 024.
For wind velocities above 17 kt the equation was:
B = 0. 113W - 0.274,
(3)
with a correlation coefficient of 0. 76 and an estimated variance of
0. 025.
B is the correction in cm (always positive), and W is the
wind speed in knots. No corrections were applied for wind speed
less than 5 knots. The method of determination of the linear regression equations is given by Li (1964, p. 306).
It should be noted that the wind was from the northwest quadrant
on 55% of the observations. This wind direction introduced the only
observable error into the observations, and no corrections were
applied for winds from other directions. At 10 knots the correction
was 0. 36 mm and at 20 knots it was 0. 99 mm.
18
Allowance was also made for precipitation. The accuracy of the
precipitation measurement was less than the accuracy of the hook
gage.
Such inaccuracy is inherent in the method of determining pre-
cipitation. For instance, mist often settled on the funnel of the rain
gage and little drained into the measuring tube. It was possible,
however, to measure a rise of the water level in the evaporation pan
at the same time. Rain corrections were applied in the computation
of daily evaporation amounts as the accuracy of the rain gage was
considered adequate when data were integrated over an entire day.
No corrections for precipitation were applied to the observations of
shorter intervals.
A greater complication was the presence of mist in the area.
Mist did not fall heavily enough to be measurable in the rain gage
but did effect a detectable rise in the water level of the evaporation
pan.
During times when rain or mist prevailed I discontinued the
frequent observations of evaporation. Mist frequently appeared about
2200 each evening. Thus, evaporation observations were often cur-
tailed at night.
Data Analysis
The data were processed using a slide rule, a calculator and a
computer. The calculations of atmometer rates (Ea) were done with
sufficient accuracy with the slide rule. A calculation was utilized
19
to do some of the remaining work.
Both IBM 1410 and 1620 computers were used to process the
bulk of the evaporation data. The principle tasks performed on the
computers were the calculations of the average hourly values of
evaporation, wind velocity, relative humidity, temperature of the
bay water, temperature of the air, and temperature of the pan water.
The equations correcting the evaporation observations for the effects
of wind and thermal expansion of sea water were also solved by cornputer. Tables of vapor pressure for air and water were part of the
program, and the values of vapor pressure were taken from them
by interpolation. Vapor pressure was averaged for hourly values
and was also used in the solution of the evaporation equation.
The
average wind velocity between any two successive observations was
used in the calculations.
20
DISCUSSION OF RESULTS
The Evaporation Day
An examination of a typical evaporation day in Newport, Oregon,
can now be made (Figures 6, 7). From 2400 to 0800 evaporation was
negligible. The wind velocity was usually between 0 and 1 knot and
the vapor pressure difference between the water (for both pan and
bay) and the air was at a minimum, or even negative. This condition
required that the evaporation rate be close to zero or that precipitation occur directly on the water surface. On many instances, between 2400 and 0800, the water level in the pan rose slightly, as
measured on the hook gage, indicating the formation of dew on the
water surface. It was also quite common for heavy fog or mist to be
present all night. The rain gage was not adequate to determine accurately such small amounts of precipitation (often totaling less than
0. 05 mm).
Thus, between 2400 and 0800 little or no evaporation
occurred.
Between 0800 and 0900 the wind velocity and the vapor pressure
difference (ew
ea) for both bay and pan usually began to increase.
Evaporation also began to increase. Usually any fog or mist present
began to dissipate about this time.
The wind generally increased until around 1600, and then de-
creased. There was an increase in the pan
and
bay vapor pressure
17
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-
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10
9
60
00 01 02 03 04 05 06 07 0809 10 It 12 13 14 5 16
time(hou rs)
r
7 18 19 20 21 22 23 24
Figure 6. Average hourly vapor pressure of pan water, bay water and air. The
average hourly relative humidity is also shown.
N
N.)
N.)
velocity.
wind and evaporation pan cover, cloud hourly Average
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23
difference (Figure 6) in the afternoon. The wind and vapor pressure
factors both acted to cause high evaporation in the afternoon. Cloud
cover also decreased in the afternoon.
As evening approached, the wind dropped, the vapor pressure
difference for both pan and bay decreased, and the observed evaporation decreased. Between 2000 and 2200 the air temperature approached the dewpoint, often with fog or mist coming in from the sea.
Thus, by 2200 to 2400, evaporation had essentially stopped and it
remained close to zero throughout the night.
Therefore, about
95%
of the day's evaporation occurred during
a 12 hour period from 1100 to 2300 each day.
The maximum pan
evaporation rate was about 0. 5 mm/hr in the afternoon.
It is to be emphasized that the above conditions are representa-
tive of a typical day during the summer. However, they are believed
to represent an adequate estimate of the average day because the
marine atmosphere of the Oregon coast, at least during the summer
months, is quite monotonous (i. e. little day to day variation occurs).
Normally there
is
a high pressure system off the coast (Figure 8),
and this condition is responsible for much of the weather that occurs
(Lane,
1965).
The weather conditions during the
months
of this study
were nearly normal as revealed by U. S. Weather Bureau Climatological Data
(1966).
There were a few days during this study during
which a low pressure system existed off the coast. During these
24
600 N
7
Figure 8. Normal surface air pressure (in mb) over the Northeast
Pacific Ocean, based on U. S. Weather Bureau Normal
Weather Chart (August).
0
0.8
0.6
E
E
0.4
0
0
0
4-
0
0
0
Q.
0
>
.0
0
QQ0
0
0000
0.0
0
0
-
F'
I
I
0
5
10
I
I
I
30
ao
25
wind speed (kt)
15
35
40
Figure 9. Average pan evaporation observed at various wind speeds.
25
days evaporation rates were generally much lower than average.
Both the wind velocities and the values of vapor pressure differences
(e
ea) for pan and bay were lower than average during these
periods.
Evaporation Correlated to Wind Speed
A strong correlation between evaporation and wind speed was
found (Figures 7 and 9). In Figure 9 each point represents the
average pan evaporation observed at each wind speed. The lack of
good correlation for wind speeds above 20 kt is probably due, at
least in part, to the dearth of observations above 20 kt.
Evaporation as a Function of Height Above the Sea Surface
In this study it was attempted to measure the change of evaporation with vertical distance above the sea surface by using atmometers mounted in several positions above the bay surface. The
increase in evaporation with the increase in height that the atmo-
meters revealed (Figure 10), reflects an increase in wind velocity
and a decrease in air vapor pressure with an increase in height.
Each point on Figure 1 0 represents the average ratio between evaporation determined at the given height above the sea surface and the
evaporation rate at 5. 5 m. The average of 81 observations was used
in the determination of the value of each point. These studies did
26
I00
I90
a
80
14)
70
60
50
0
I
2
3
4
5
height Cm)
Figure 10. Atrnometer evaporation rate
at 5. 5 n-i
100%.
7
6
(Fa)
vs
6
height.
sate
27
not show the amount of error introduced due to the vapor pressure
of the pan water exceeding that of the bay water. However, these
studies give a correction factor 0. 65 to be multiplied by the evapor-
ation rate at the pan, to correct for most of the error due to the pan
being above the bay surface (Laevastu, 1960).
Daily Evaporation Rate
The average daily pan evaporation rate was 3. 67 mm/day for
76 days of data. If the average daily rate is multiplied by the cor-
rection factor (0. 65), to obtain evaporation at the sea surface, a
daily rate of 2. 39 mm/day is obtained. If it is assumed that evapor-
ation proceeds at about the same rate for the entire year, this
estimate yields an annual rate of sea surface evaporation of 87
rn/year.
Estimation of Sea Surfac:e Evaporation Using Atmometers
The possibility of using atmorrieters to measure evaporation from
the sea surface was investigated. The atmorneter evaporation rates
were correlated with pan evaporation rates. Figure 11 shows the
c1istrbution of points obtained by plotting the evaporation pan rates
(E) against atmometer rates (Ea) for observations taken sirnultaneously, when both instruments were 5. 5 m above the bay surface.
A linear regression equation determined was:
'.4
1.2
.cLO
E
C
0
0.6
-I
0
0.4
C
-0.2
0
I
2
3
4
5
otmometer evaporation (mlfhr)
Figure 11.
Correlation between atmometer evaporation (F) and pan
evaporation (F).
E
z
0.06 + 0. 12 E a ,
(4)
where Ea has units of mi/hour and E has units of mm/hour. The
correlation coefficient was 0.
57
and the sample variance was 0. 21.
To estimate the evaporation from the sea surface (F), multiply
equation (13) by the correction factor (0. 65) and 24 hr to obtain:
E
o
= 0.94 + 0. 08Ea (mm/24 hr.).
(5)
By using (14) with a known evaporation rate from an atmometer
5. 5
m above the sea surface it is possible to estimate the amount
of evaporation at the sea surface. The significance of equations
(4) and
(5)
is that evaporation in volumetric quantities from the
spherical surface of an atmometer can be correlated with evaporation in linear quantities from a flat surface of an evaporation pan
or the sea surface. Equations (13) and (14) are obtained by statistical means and as such provide only estimates.
The correlation
coefficient between the two types of measurements is of sufficient
magnitude to indicate that there is a real correlation between them,
but the variability and hence limited reliability of such estimates
is obvious from the distribution of points shown in Figure 11.
On one occasion atmometers were used at sea. The observer
placed the atmometers on the rail of a stationary, off-shore, oilwell drilling vessel. The hourly evaporation rates were determined
from the atmometers for two days. The wind during this period did
30
not exceed 20 kt, so there was not enough wind to send spray up to
the atmometers in observable amounts. The atmometers were cali-
brated after they had been used at sea and no significant change in
operating characteristics was detected. Thus, the atmometers apparently were not notably affected by the sea conditions occurring
during the time that they were used at sea. The water evaporated
by the atmometers was 11.08 ml on 1 September and 14.43 ml on
2 September. By using equation (5), an average daily evaporation
rate of 1. 96 mm/day at the sea surface was computed.
It is interesting to note that at this location, 1 8 miles at sea,
a diurnal variation of evaporation was found. This suggests that
evaporative conditions are similar for some distance from the bay
at Newport.
This supports the original assumption that evaporation
as estimated in Yaquina Bay can be used to estimate evaporation on
the open ocean in the vicinity of the bay, during the summer.
The conditions for the offshore study were ideal because the
sea spray was negligible and the barge was very stable. It may be
concluded that atmometers are of some use in evaporation studies
at sea under normal good-weather conditions. Their use would
preclude those problems associated with using evaporation pans
at sea such as water spilling out and spray getting into them.
31
Equation of Evaporation
An equation of evaporation was determined in the form:
E
z
(C + KV) (e w -e a ),
(6)
where E is pan evaporation, V is the wind speed, ea is the air
vapor pressure, e is water vapor pressure, and C and K are
constants. The tern-is Ez , V, e w , and e a were determined for each
weather observation. The constants C and K were obtained by using
a computer program which performed a stepwise linear regression
on the data. The results were:
C = 0. 029
(hr1),
(7)
with a standard error of 0. 010 and,
K = 0.003 (naut. mi.
(8)
with a standard error of 0. 0008. The correlation coefficient was
0.44 and the sample size was 192. Therefore, the equation ob-
tamed is:
E
z
= (0. 029 + 0. 003V) (e w
e ).
a
(9)
To estimate evaporation at the sea surface (E), multiply
equation (9) by the constant (0. 65) and obtain:
E
0
= (0. 019 + 0. 002V) (e w - e a ).
(10)
A graphical representation of this equation is given in Figure 12.
The wind speed (kt) and air vapor pressure must be determined
0.160
(e-e0) =3.0
0.140
2.5
0.120
0.100
0.080
1.5
a
o0. 0.060
a
0.040
0.5
o.oao
0.000 -
0
5
10
15
wind speed (kt)
20
25
30
Figure 12. Estimated sea. surface evaporation as a function of the sea surface water
vapor pressure (e), air vapor pressure (e), and wind speed (kt).
(J
NJ
33
about 5. 5 m above the sea surface in order to estimate sea surface
evaporation using the graph.
34
COMPARISONS WITH OTHER STUDIES
Reduction of Pan Evaporation to Sea Surface Evaporation
Defant (1951) and Laevastu (1965) have discussed the results of
several studies in this field. Such studies yield values of 0. 40 to
0. 58 to be multiplied by the pan evaporation rate at a height of 8 m
above the sea surface.
The constant (0. 65) determined in this study
agrees fairly well with the other estimates.
Average Daily Sea Surface Evaporation
The average daily sea surface evaporation determined in this
study was 2. 39 mm/day (87 cm/year).
This estimate falls in the
range of estimates that have been determined during several other
studies. By using the results of pan measurements and weather ob-
servations from various parts of the Pacific Ocean, Sverdrup,
Johnson and Fleming (1942), obtained an estimate of 94 cm/year
(2. 58 mm/day), for the latitude of this study.
Jacobs (1951) esti-
mated evaporation at 0. 63 mm/day, using an empirically derived
equation.
Defant (1961) estimates the evaporation from the sea surface at
1. 81 mm/day for the latitude of this study. Sverdrup (1951), gives
the following estimates for the latitude of this study:
35
1. 80 mm/day, by extrapolation of evaporation pan data from
the coasts of the world's oceans,
2. 11 mm/day, by actual evaporation studies at sea and by
inference from weather observations at sea,
1. 58 mm/day, from heat budget estimates,
2. 00 mm/day, frorr meterological observations.
Equation of Evaporation
Rohwer (1931) and Kohler (1954) have developed an equation
similar to the equation of evaporation determined in this study.
Table 1 compares the values of the constants (C and K) as determined
in this study with those of Rohwer and Kohler.
Table 1. A comparison of the constants of
evaporation as determined by the
author, Rohwer (1931), and Kohier (1954).
C
K
Author
0.029
0.003
Rohwer
0.016
0.005
Kohler
0.017
0.005
It is apparent that the equations compare fairly well, at least for
wind speeds up to about 20 kt.
36
SUMMARY
Pan evaporation varied greatly with the time of day. Most
evaporation occurred between 1100 and 2300 each day, with the maximum evaporation occuri.ng in the afternoon. The average daily sea
surface evaporation was estimated as 2. 39 mm/day. A high correlation between wind speed and pan evaporation was found.
A correction factor of 0. 65 was obtained through the use of
atmometers. This correction factor was multiplied by pan evapor-
ation to estimate sea surface evaporation.
An empirical equation of evaporation was obtained expressing
evaporation as a function of wind speed and the difference between
air and water vapor pressure. The constants of the equation were
determined by statistical means and as such are only estimates of
the actual constants.
A method of measuring sea surface evaporation at sea through
the use of atmometers and an empirically derived equation was examined.
This method gave good results during a short trial at sea.
Most observational error due to thermal expansion of the water
and wind were removed. Several attempts to lower the temperature
of the evaporation pan water were made, none of which were successful.
Thus the temperature of the evaporation pan water was often
higher than that of Yaquina Bay surface water. However, the results
37
of this study compare fairly well with those of other studies obtained
by other means which would indicate that the effect of the higher
temperatures was not significant.
BIBLIOGRAPHY
Defant, Albert. 1961. Physical oceanography. Vol.
Pergamon Press. 729 p.
1.
New York,
Jacobs, W. C. 1951. Large scale aspects of energy transformation
over the oceans, In: Compendium of meteorology, ed. by Thomas
F. Malone. Boston, Mass., American Meteorological Society.
p. 1057-1070.
Kohier, M. A. 1954. Lake and pan evaporation water loss investions: Lake Hefner Studies. U. S. Geological Survey. Professional
Paper 269: 127-148.
Laevastu, T. 1960. Factors affecting the temperature of the surface
layer of the sea. Societas Scientiarum Fennica, Commentationes
Physico-mathematicae 25(1): 1-135.
Lane, R. K. 1965. Climate and heat exchange in the oceanic region
adjacent to Oregon. Ph. ID. thesis. Corvallis, Oregon State University. 1.15 numb. leaves.
Livingston, B. E. 1935. Atmometers of porous porcelain and paper,
their use in physiological ecology. Ecology 16: 438-472.
Li, Jerome C. R. 1964. Statistical inference. Vol. 1, Rev. ed.
Ann Arbor, Edwards Brothers, Inc. 658 p.
Maughan, P. N. 1965. Measurement of radiation energy over a
mixed water body. Ph. ID. thesis. Corvallis, Oregon State University. 125 numb. leaves.
Rohwer, C. 1931. Evaporation from water. Washington, ID. C.
96 p. (U. S. Dept. of Agriculture. Technical bulletin no. 271)
Roll, H. V. 1965. Physics of the marine atmosphere. New York,
Academic Press. 426 p.
Sverdrup, H. U. 1937. On the evaporation from the oceans.
Journal of Marine Research 1: 3-14.
Evaporation from the oceans. In:
Compendium of meteorology, ed. by Thomas F. Malone. Boston,
Mass., American Meteorological Society, p. 1071-108 1.
1951.
39
Sverdrup, H. U., Martin W. Johnson and Richard H. Fleming. 1942.
The oceans. Englewood Cliffs, N. 3., Prentice Hall. 1087 p.
U. S. Weather Bureau. 1962. Instructions for climatological
observers. Washington, D. C. 76 p.
1965.
Climatological data. Oregon. Vol. 71.
Northern hemisphere, normal weather
chart. Washington,D. C. 1 sheet. (Technical paper no. 21)
1965.
Van Dorn, W. G. 1954. Wind stress on an artificial pond.
Journal of Marine Research 12: 249-276.
APPENDICES
40
APPENDIX I
Definitions of Terms
B
Correction for the effect of tilting of the evaporation pan
water, in cm.
Temperature, degrees centigrade.
C
Constant of the evaporation equation in (hr1).
c
Coefficient of thermal expansion of sea water.
cm
Centimeters.
D
Depth of the water in the evaporation pan.
La
Atmometer evaporation (mL/hr), measured 5. 5 m above
the sea level.
£
Sea surface evaporation.
F
Pan evaporation (mm/hr), measured 5. 5 m above mean
high water.
ea
Air vapor pressure, mm of mercury.
e
Water vapor pressure, mm of mercury.
H
Correction for thermal expansion of pan water.
hr
Hour.
K
Constant of the evaporation equation tiaut. mi.
kt
Knots.
langley (ly) Gram calories/cm2.
m
Meters.
mb
Millibars.
1)
41
ml
Milliliters.
mm
Millimeters.
naut. mi.
ppt
Nautical mile.
Parts per thousand.
Solar radiation (ly/min).
V
Wind speed, kt.
Difference in pan water temperature between observations.
Z
Distance above the water surface.
42
APPENDIX II
Data
Explanation of wind direction, present weather, and cloud type
codes used.
Wind Direction
Code
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
Wind Direction
NE
NNE
ENE
F
FSF
SE
SSE
S
SSW
SW
WSW
W
WNW
NW
NNW
CALM
FNE
Present Weather
Present Weather
Code
01
02
03
04
05
06
07
08
09
10
12
14
blue
overcast
increasing clouds
decreasing clouds
light fog
moderate fog
heavy fog
light mist
heavy mist
fog and mist
light rain
broken clouds
43
Cloud Type
Code
01
02
03
04
05
06
07
Cloud Type
Stratus
NimbostratUs
Stratocumulus
Cumulus
AltostratUs
Cirrus
None
44
DATA
4..
:2
4..
4)
4)
0
4.
4)
4)
4)
4)
4)
4)
C)
4.
4)
.4)
5
X
06
06
06
06
06
06
06
06
06
06
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
c
30 1400 04.994
30 1540 01,698
30 1600 07.749
30 1700 07.690
30 1800 07.731
0 2000 07.707
30 2100 07.730
30 2200 07,709
30 2300 07,693
30 2400 07,697
01 0800 07.763
02 1000 07.509
02 1200 07,833
02 1300 07.875
02 1400 07.704
02 1600 07.577
02 1800 07,534
02 2000 07.481
02 2200 07.485
02 2400 07,485
03 0800 07,450
03 0900 07,447
03 1000 05.344
07 1100 03.759
07 1230 07,741
07 1400 07.821
07 1600 07.717
07 1800 07.730
07 2000 07.645
09 1530 07.038
09 1600 07.000
09 1800 06.969
09 2000 06,931
09 2400 06.950
10 0800 06.971
10 1000 06,963
14 1100 05.094
14 1200 05.089
14 1345 07.975
14 1400 07.953
14 1430 07.991
14 1500 08,022
14 1600 07,980
14 1800 07,958
4)4)
4)
H
18.8
11.5
11.7
12.9
13.2
13.4
12.8
12.3
12.4
12.1
11.7
13.2
13.9
16.3
17.8
17.8
16,9
14,5
12.7
12.2
11,5
12.2
13.0
16.5
15.1
18.3
21.1
21.0
20.0
16.1
17.3
19,4
18.5
15,2
12,9
14.6
14.9
17.4
13.3
14,5
15,8
16.8
18,9
18.6
4)
H
09,1
09.1
09,1
12,7
11.6
10,3
09,7
09.5
09.3
09,4
12,0
13.1
13.2
12.1
10.2
09.4
10.0
10.9
10.9
10.0
10.4
11.9
12.7
12,2
11.9
13.0
12.6
12,8
10.0
12.2
12.2
12.2
11.0
09,8
12.1
11.3
14.0
13.0
12.3
11,3
10.9
10.9
10.9
12,7
<H
clj
11,8
12.1
11.7
12.2
11.7
11,4
11.3
12.2
12,0
12.4
12.2
12.9
13.4
12,8
13.1
12.8
12.2
10.6
10.9
10.1
11.7
12.2
12.8
13.9
14.0
13.9
15.0
13.9
12.9
15.1
14.2
14.7
14.4
14.5
14.5
15.6
14.9
14.4
14.5
14.5
15.0
15.1
15.6
14.9
.4)
4)
4)
U
-4)
-
0
C)
094
094
094
094
094
100
100
094
100
100
100
085
085
085
088
088
094
100
097
099
095
085
088
094
094
094
086
094
099
083
080
080
085
094
097
086
095
097
091
091
083
083
081
089
01
01
01
01
14
10
12
12
12
12
14
01
01
01
14
01
01
14
14
16
16
14
14
14
14
14
14
14
14
12
12
12
09
09
09
09
14
14
14
14
14
14
14
14
25
25
20
10
05
05
00
00
00
00
05
10
10
20
30
30
25
10
03
00
00
05
05
12
14
16
17
12
08
06
06
04
06
05
10
08
12
15
20
20
15
15
15
08
o
H
01
01
01
01
01
01
01
01
01
02
02
01
01
01
01
01
01
01
01
01
01
01
01
01
01
01
01
01
01
02
02
02
02
02
01
01
08
08
08
08
08
08
08
08
4..
-4)
C
4)
4)
4)X
4)
o
J
06
05
04
10
10
10
10
10
10
10
10
08
08
06
05
01
02
01
02
04
10
10
10
10
10
10
10
10
10
10
10
10
06
06
09
10
00
00
00
00
rZ
U
C)
02 06.09
02 66.66
02-00.51
11 00.59
11-00.41
10 00.24
05-00.23
05 00.21
05 00.16
10-00,04
13-00.02
02 02.54
02 66.66
02-00,42
02 01.71
05 01.27
10 00.43
10 00,53
10-00.04
10 00.00
02 00,35
02 00,03
0? 66,66
02 15.85
02 66,66
02-00.80
02 00.44
02 00.47
02 00.85
10 66.66
10 00.38
14 00.31
14 00,36
14-00.19
14-00.22
14 00.08
01 19.48
01 00.05
01 66.66
01 00.22
H
025,00
066.66
000.33
001.00
001.00
002.00
001.00
001.00
001.00
001.00
008.00
026.00
066.66
001.00
001.00
002.00
002,00
002.00
002.00
002.00
008,00
001.00
066.66
091.00
066.66
001.50
002.00
002.00
002.00
066.66
000,50
002.00
002.00
004.00
008,00
002.00
097,00
001.00
066.66
000.25
00 01-00.38000.50
00 01-00.31 000.50
00 01 00,42 001.00
09 14 00.22 002.00
45
06
06
06
06
06
06
06
06
06
06
07
07
07
01
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
30
30
30
30
30
30
30
30
30
30
01
02
02
02
02
02
02
02
02
02
03
03
03
07
07
07
07
07
07
09
09
09
09
09
10
10
14
14
14
14
14
14
14
14
1400
1540
1600
1700
1800
2000
2100
2200
2300
2400
0800
1000
1200
1300
1400
1600
1800
2000
2200
2400
0800
0900
1000
1100
1230
1400
1600
1800
2000
1530
1600
1800
2000
2400
0800
1000
1100
1200
1345
1400
1430
1500
1600
1800
04.994
07.698
07.749
07.690
07.131
07.707
07,730
07.709
07,693
07.697
07.763
07.509
07,833
07.875
07.704
07.577
07.534
07.481
07.485
07.485
07.450
07.447
05.344
03.759
07.741
07.821
07.777
07.730
07.645
07,038
07.000
06.969
06.931
06.950
06.971
06.963
05.094
05.089
07.975
07.953
07.991
08.022
07.980
07,958
18.8 09.1
11.5 09.1
11.7 09.1
12.9 12.7
13.2 11.6
13.4 10.3
12.8 09.7
12.3 09,5
12.4 09.3
12.3 09,4
11.7 12.0
13.2 13.1
13.9 13.2
16.3 12.1
17.8 10.2
17.8 09,4
16.9 10.0
14,5 10.9
12.7 10.9
12.2 10.0
11,5 10.4
12,2 11,9
13.0 12.7
16.5 12.2
15.1 11,9
18.3 13.0
21.1 12.6
21,0 12.8
20.0 10.0
16.1 12.2
17.3 12.2
19.4 12.2
18,5 11,0
15.2 09.8
12.9 12.1
14,6 11.3
14.9 14.0
17.4 13.0
13.3 12.3
14,5 11.3
15.8 10,9
16.8 10,9
18,9 10.9
18,6 12.7
11.8
12.1
11.7
12.2
11.7
11.4
11.3
094
094
094
094
094
100
100
01 25 01 06 02 06.09 025.00
01 25 01 05 02 66.66 066,66
0]. 20 01 04 02-00.51 000.33
01 10 01 10 11 00.59 001.00
14 05 01 10 11-00.41 001.00
10 05 01 10 10 00.24 002.00
12 00 01 10 05-00.23 001.00
12.2 094 12 00 0]. 10 05 00.21 001.00
12.0 100 12 00 01 10 05 00.16 001.00
12.4 100 12 00 02 10 10-00.04 001,00
12.2 100 14 05 02 10 13-00.02 008.00
12.9 085 01 10 01 08 02 02.54 026.00
13,4 085 01 10 01 08 02 66.66 066.66
12,8 085 01 20 01 06 02-00.42 001.00
13.1 088 14 30 01 05 02 01.71 001.00
12.8 088 01 30 01 01 05 01.27 002.00
12.2 094 01 25 01 02 10 00.43 002,00
10.6 100 14 10 01 03 10 00.53 002.00
10.9 097 14 03 01 02 10-00.04 002.00
10.1 099 16 00 01 04 10 00.00 002.00
11,7 095 16 00 01 10 02 00.35 008,00
12.2 085 14 05 01 10 02 00,03 001.00
12.8 088 14 05 01 10 02 66.66 066.66
13.9 094 14 12 01 10 02 15.85 097.00
14.0 094 14 14 01 10 02 66,66 066.66
13.9 094 14 16 01 10 02-00.80 001.50
15.0 086 14 17 01 10 02 00.44 002.00
13.9 094 14 12 01 10 02 00.47 002.00
12.9 099 14 08 01 10 02 00.85 002.00
15.1 083 12 06 02 ]0 10 66.66 066.66
14.2 080 12 06 02 10 10 00.38 000.50
14.7 080 12 04 02 10 14 00.31 002.00
14.4 085 09 06 02 06 14 00.36 002.00
14.5 094 09 05 02 06 14-00,19 004,00
14.5 097 09 10 01 09 14-00.22 008.00
15,6 086 09 08 01 10 14 00.08 002.00
14.9 095 14 12 08 00 01 19.48 097.00
14.4 097 14 15 08 00 01 00.05 001,00
14.5 091 14 20 08 00 01 66.66 066.66
14.5 091 14 20 08 00 01 00.22 000.25
15.0 083 14 15 08 00 01-00.38 000.50
15.1 083 14 15 08 00 01-00.31 000.50
15.6 081 14 15 08 00 01 00.42 001.00
14.9 089 14 08 08 09 14 00.22 002.00
46
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
07
08
08
08
08
08
08
08
14
14
14
15
15
16
16
16
16
16
16
16
16
16
17
17
21
21
21
21
21
21
21
21
21
21
21
21
22
22
22
23
23
23
23
23
23
23
23
23
23
23
23
23
24
24
30
30
30
30
30
31
31
04
04
04
04
04
04
04
2000
2200
2400
0400
0800
1045
1200
1500
1600
1800
2000
2100
2200
2400
0800
1000
1100
1310
1445
1530
1620
1706
1809
2000
2100
2200
2300
2350
0400
0836
0930
1040
1150
1230
1400
1510
1600
1603
1710
1900
1905
2030
2200
2300
0900
0950
1720
1900
2030
2130
2300
0734
1000
1100
1240
1410
1615
1700
1710
1940
07.920
07,919
07,927
07,909
07.895
07,241
07.236
06.468
06,483
06,433
06,455
06.452
06.463
06.452
06.430
06,369
05.255
07.415
07,410
07.420
07,394
07.383
07.363
07.290
07.281
07,279
07.277
07.272
07.254
07.244
07.235
06.742
06.726
06.651
07.242
07,235
07.175
07,850
07.766
07.781
07.105
07.082
07,051
07.045
06,977
06.994
06.697
06,685
06,692
06.691
06.689
06.666
06.664
06.058
05,951
05.926
05,777
05,779
06.244
06.079
18,4
17.0
16,1
14.6
15.4
15.2
16.8
13,5
14.9
15.8
14,8
14,3
13,5
12.9
13,0
14,8
16.8
14.3
18.0
19.1
19.4
19.5
19.0
16,9
15.6
15.0
14.4
14.1
12.0
12.3
13.5
17.5
18,4
20.1
16.3
19.4
19.8
19.1
19.0
18.3
18.3
17.5
16.4
15.6
12.1
12.5
16.1
16.2
15.7
15.3
15.0
13.4
15.5
16.5
15.6
18.4
19.0
19.3
19.3
17.4
12.5
11.5
11.1
10.5
15.0
15,0
13,9
09.9
10.3
12.0
12.3
12.3
11.3
10.6
14.2
15.3
12.9
13.0
12,7
12.3
12.6
12.7
11.7
10.7
12.4
12,8
12.4
12.6
12.2
11.9
13.3
13.5
13.6
14,0
14.1
14.2
13.5
13,5
12.1
11.3
11.3
10.0
16.5
14.5
11.3
12,1
12.9
13.6
13.9
13.2
12.7
12.7
13.0
14.3
15,2
14.5
14.4
15.0
15.0
12.2
14.9
13.9
13.7
13.3
15.0
15.0
15.5
15.1
15.1
14.3
13.9
13,7
13.5
13.3
15.5
15.8
13.2
13.9
16.7
16.5
16.4
16,3
15.9
15.1
15.1
14.2
13,1
12.6
10.9
12.2
14.4
15.3
16.0
16.8
17.0
20.9
19.6
19.6
18.6
16.2
16.2
14.4
14.0
12.2
11.4
12.0
15.9
14.2
14.4
14.4
14.5
14.8
16.7
15.9
16,4
16.7
17.0
17.1
17.1
15.1
091 14 08 01 10 10 00.38 002.00
100 14 04 01 10 07 00.01 002,00
100 14 02 02 10 10-00.08 002,00
100 14 05 02 10 12 00.18 004.00
085 16 00 02 09 05 00.14 004,00
094 14 23 02 01 14 06,54 025.75
089 14 25 02 01 14 00,05 001.25
094 14 33 02 01 14 66.66 066.66
094 14 32 02 01 14-00.15 001.00
091 14 30 02 05 14 00.50 002.00
091 14 21 02 05 14-00.22 002.00
088 14 12 02 04 14 00.03 001.00
088 14 01 03 08 14-00.11 001.00
088 14 05 03 08 14 00.11 002.00
081 01 08 03 08 14 00.22 008.00
075 01 15 03 05 14 00,61 002.00
097 12 07 03 05 14 16.60 097.00
095 12 07 03 05 14 66.66 066.66
081 12 07 03 05 14 00,05 001.60
080 13 08 03 05 14-00.10 000.75
076 13 06 03 03 14 00,26 000.70
076 13 06 03 03 14 00.11 000.78
081 13 04 03 03 14 00.20 001.05
078 14 10 01 01 01 00,73 001.85
078 14 05 08 00 01 00.09 001.00
083 01 01 08 00 01 00.02 001.00
088 16 00 08 00 01 00.02 001.00
094 16 00 08 00 01 00.05 000.82
097 04 08 08 00 05 00.18 004.18
088 04 04 08 00 05 00.10 004.60
080 04 01 08 00 05 00.09 000.90
089 13 04 08 00 0]. 04,93 025.17
085 12 04 08 00 01 00,16 001.16
089 13 13 08 00 0]. 00,75 000,68
085 13 13 08 00 01 66.66 66.66
059 14 2. 08 00 0]. 00,07 000.80
062 14 26 08 00 01 00.60 000,80
062 14 26 08 00 0]. 66,66 066.66
066 14 25 08 00'01 00,94 001,10
084 14 20 08 00 01-00.15 001.83
084 14 20 08 00 01 66.66 066.66
083 14 10 08 00 01 00.23 001.41
085 14 02 08 00 01 00,31 001.50
01 16 00 08 00 01 00.06 001.00
100 10 06 03 10 05 00.68 010.00
090 10 06 03 10 05-00,17 000.83
100 14 21 01 08 14 66,66 066.66
100 14 19 01 10 05 00.12 000.66
094 14 10 02 10 10-00.07 000.50
094 16 00 01 10 05 00.01 001.00
094 12 03 01 10 10 00.02 001,50
094 12 02 01 10 05 00.23 008.57
094 12 04 01 09 02 00,02 001.43
097 14 10 01 01 14 07.60 097.00
092 13 14 01 01 14 66.66 066.66
02 14 13 08 00 01 00,25 001.50
071 14 19 08 00 01 01.49 002,09
069 14 15 08 00 01-00.02 000.75
069 14 15 08 00 01 66.66 066.66
089 14 14 08 00 01 01.65 002.50
47
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
06
08
08
04 1945 05.629 17.4
04 2030 05.633 16.2
0'. 2130 05.645 15.0
04 2300 05.638 14.3
05 0830 05.603 13.0
05 1030 05,567 16.3
05 1200 05.469 17.4
05 1400 05,450 19.5
05 1600 05.287 19.7
05 1830 05.172 18.2
05 2015 05.246 17.0
05 2200 05.233 15.3
05 2345 05.233 14.4
06 0830 05.089 11.7
06 1005 05,086 14.0
06 1010 05.460 14.0
06 1320 05.427 18.7
06 1325 05.051 18.7
10 1130 04.191 18.0
10 1300 05.269 14.3
10 1535 05,170 20.0
10 1637 05.057 15.2
10 1800 05,101 17.9
10 2000 05.070 17,8
10 2300 05.045 16.3
11 0400 05.039 14.8
11 0845 05.012 15.7
11 1220 04.974 20.1
11 1340 04.939 20.1
11 1345 05.414 20.1
11 1530 05.369 19.2
11 1535 04.891 19.2
12 1145 05.109 15.9
12 1510 05.079 19.1
12 1735 04.858 18.6
12 1800 04.973 18.6
12 2000 04.934 17.4
12 2325 04.860 15.6
13 0830 04.873 14.1
13 1200 04.851 19.6
13 1330 04.784 22.3
13 1500 06.518 16.3
16 1200 05.552 20.1
16 1230 05.477 20.1
16 1530 05.308 20.3
16 1712 05.245 19.3
16 1800 05.155 18.5
16 2000 05.212 16.2
16 2100 05.171 15.2
16 2200 05.177 14.6
16 2330 05,193 14.3
17 0845 05.155 13.3
17 1100 05.109 15.4
17 1230 05.092 17.1
17 1400 07.254 15.5
19 1130 07.540 16.0
19 1200 07.578 16.0
19 1315 07.567 17.8
19 1600 07,557 18,9
12.2
12.5
12.7
13.0
12.0
14.7
14.5
15.1
14,7
12.4
11.1
14.6
12.3
13.0
11.7
11.7
14.2
14.2
13.5
13.1
14.3
14.8
14.3
13.9
13.5
13.8
15.4
13.3
13.1
13.1
14.0
14.0
12.5
13.0
14.3
13.1
13.6
13.2
15.1
14.7
14.7
14,5
15,0
15.0
12.4
12.1
14.0
14.0
14.8
15.0
14,1
14.1
14.6
14.1
13.9
13.3
13.3
12.5
12.2
15.1
14.7
13.2
12.8
13.3
16.4
14.4
16.1
16.7
15.0
13.3
12.0
12,8
09.4
10,6
10.6
16.1
16,1
14.4
15,5
16.0
16.1
16.7
16.1
15.3
14.0
16.0
17.2
16.1
16,1
15.0
15.0
16.7
18.9
15.6
17.8
15.0
15.0
14.8
18.3
17.8
17.8
15,3
15,3
15.7
15.0
15.6
14.3
14.2
14.2
14.2
13.1
14.4
13,6
14,2
16.7
16,7
17.5
17,8
089 14 14 08
091 14 05 08
091 16 00 08
094 16 00 08
094 16 00 08
092 14 09 08
092 14 11 08
085 14 10 08
082 14 16 08
092 14 15 08
092 14 06 08
095 16 00 08
099 16 00 08
099 16 10 01
095 12 02 08
095 12 02 08
092 12 02 08
092 12 02 08
092 13 05 01
085 14 09 01
080 15 12 01
080 14 13 01
080 14 05 01
092 14 06 01
092 16 00 01
095 16 00 02
095 14 03 05
089 14 08 05
095 14 07 05
095 14 07 05
095 14 05 02
095 14 05 02
089 09 11 01
075 09 15 03
099 14 02 02
084 09 10 02
095 09 10 03
095 08 02 01
095 06 03 08
075 14 03 03
075 14 03 03
075 14 03 03
083 14 08 08
083 14 16 08
083 14 19 08
083 14 18 01
083 14 18 02
088 01 09 01
091 01 09 01
088 01 07 01
088 16 00 01
091 14 02 01
085 14 07 01.
091 14 09 01
085 14 08 07
092 09 00 01
092 09 11 01
089 09 12 01
085 09 10 01
00
00
00
00
00
00
00
00
00
00
00
00
00
10
00
00
00
00
05
05
02
01
01
03
10
10
09
09
09
09
10
10
10
09
10
09
09
10
00
01
04
03
00
00
00
01
01
05
08
07
10
10
07
08
04
10
10
10
10
01 66,66
01-00.04
01-00.15
01 00.07
01 00.33
01 00.36
01 00,98
01 00,19
01 01.63
01 01.15
01-00,74
01 00.13
01 00.00
07 01,44
01 00.03
01 66.66
01 00.33
01 66,66
14 08,60
14 66.66
14 00,99
14 66.66
01-00.44
01 00.31
02 00.25
02 00.37
02 00.27
02 00.38
02 00,35
02 66.66
12 00.45
12 66.66
02 00,74
14 00,30
02 00,33
12 01.06
02 00.39
02 00.74
01-00.13
01 00,22
01 00.67
01 66,66
01 09.66
01 00.85
01 00.69
01 00.43
01 00.90
03-00.57
02 00,41
02-00.06
02-00.16
02 00.38
14 00,46
02 00,17
01 66.66
02 66.66
02 02.09
02 00.11
02 00.10
066.66
000.75
001.00
001.50
009.50
002.00
001.50
002.00
002.00
002.50
001.75
001.75
000.75
009.75
001.55
066,66
003.18
066.66
094.00
066.66
002,59
066,66
001.40
002.00
003.00
005.00
004.75
003.58
001.33
066.66
001.75
066.66
018,16
003.42
002.00
002.83
002.00
003.42
009.09
003.5b
001.50
066.66
069.00
000.50
003,00
001.80
000.80
002.00
001,00
001.00
001.50
009,25
002.25
001.50
066.66
066.66
046.00
001.25
002,75
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
19
19
19
20
20
20
20
23
23
23
23
23
24
24
24
1815
2030
2330
0845
1100
1230
1344
1215
1520
1810
2000
2350
0900
1015
1200
07.499
07.489
07.471
07.643
07.652
07.635
07.771
06.940
06.877
06.795
06.770
06.724
06.679
06.675
06.657
08 2'. 1300 07.680
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
08
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
24
24
24
24
24
24
25
25
25
27
27
27
27
27
27
27
27
31
03
03
03
07
07
07
07
07
07
07
07
07
08
08
08
08
08
08
08
10
10
10
10
10
10
10
1400
1530
1620
1800
2115
2400
0900
1200
1430
1130
1200
1415
1600
1815
1930
2030
2115
1130
0845
0945
1030
1100
1200
1310
1500
1820
1945
2035
2300
2359
0845
1200
1400
1445
1600
1845
2030
1100
1210
1330
1540
1700
1820
2015
07.684
07.623
07.238
07.247
07.242
07.337
07.389
07.384
07.328
06.374
06.332
06.192
06.044
05.985
05.945
05.947
07.822
05.947
05.145
05.145
07.738
05.997
05.991
05,898
05.817
05.683
05,671
05,668
05.653
07.836
07.852
07.840
07.814
07.466
07.440
07.431
07.400
07,173
07.119
07.076
06.998
06.955
06.902
06.927
18.0
16.6
16.0
14.8
16.9
18.5
16.2
19.6
22.6
22.4
21.1
18,5
16,5
16.9
19.5
16,3
19.0
21.3
17.5
18.1
17,5
16.9
15,7
20.3
23.6
16.6
16.6
18.2
17,9
17.2
15.7
15.0
15,4
14,7
13,6
13.6
12.3
15.6
16.5
18,1
19,4
18,6
17,1
16,3
14,6
09.9
10,8
13.1
14.6
14.6
15,7
15.8
14.9
13.3
14.3
15,5
17.0
17.2
16.3
14.6
11.5
12.7
12.7
13.2
13.6
13.7
14.5
14.6
16.3
15.9
15.7
15.2
15.5
16.2
14,7
14.6
16.2
16.3
16.1
15,8
15,1
15.0
16.1
16.0
16,5
15.1
15.1
14,4
15,7
15,5
16.5
16.4
15.9
11.4
10.8
10,8
12.4
14.2
11.0
10.1
12,0
12.4
11.6
11.3
10.1
10.0
12.0
10.5
09,8
09,8
11.8
11.6
11.3
10.6
10.9
10.2
10.6
11.2
11.0
11.5
16.1 089 09 09 01 10 02 00.58 002.25
15.0 095 09 01 02 10 02 00.35 002.25
15.3 094 09 06 02 10 12 00.18 003.00
15.0 094 16 00 02 10 02-00.45 009.25
17.5 082 09 06 03 06 14-00,09 002.25
17.8 079 09 07 03 06 14 00.17 001.50
18.6 080 11 08 03 08 14 66.66 066.66
18.6 075 13 02 05 10 02 08.31 069.50
17.8 082 11 05 05 09 02 00.63 003.08
18.1 082 12 05 06 08 14 00,82 003.83
17.0 089 10 01 06 05 14 00.25 001,83
15.6 094 16 00 01 10 02 00.46 003.83
15,9 092 05 02 01 10 02 00,45 009.17
17.8 082 05 02 01 10 02 00.04 001.25
16.4 084 14 05 01 09 02 00,18 001.75
18.6 073 14 07 01 05 14 66.66 066.66
18,6 073 14 07 03 04 01-00.04 001.00
18.3 080 14 10 03 03 01 00.61 001.50
18.6 078 14 11 05 08 14 66.66 066.66
17.7 083 13 04 05 10 12-00.09 001.66
17.2 089 16 00 01 10 02 00.05 003.25
16.1 098 09 03 02 10 15-00,44 002.75
16,7 089 16 00 05 09 14 00.12 009.00
18.3 080 10 07 07 08 14 00.05 003.00
19.0 075 10 07 05 07 14 00.56 002.50
16,8 061 14 17 06 05 14 09.54 045.00
16.8 06]. 14 17 06 05 14 00.42 000.50
16.7 064 14 20 07 07 14 01.40 002.25
16.7 059 15 20 08 00 01 00.48 001.75
16,2 063 14 14 08 00 01 00.59 002.25
15,4 068 01 12 08 00 01 00.40 001.25
15,0 067 15 08 08 00 01-00,02 001.00
14.5 068 14 03 08 00 01 66,66 066.66
09.4 099 10 04 01 10 06 18,75 081.75
14.7 076 16 00 03 09 02 08,02 069.25
14.7 076 16 00 03 06 01 00.00 001.00
15.3 058 14 09 03 08 02 66,66 066.66
17.5 051 16 00 08 00 01 22.59 097.00
18.1 041 10 02 08 00 01 00.06 001.00
16.2 057 14 15 08 00 01 00.93 001.17
15,6 073 14 18 08 00 01 00.81 001.83
15.7 077 14 11 08 00 01 01.34 003.33
14.9 078 14 09 08 00 01 00.12 001.42
12.8 088 16 00 08 00 01 00.03 000.83
11.3 092 16 00 08 00 01 00.15 002.42
10.6 094 16 00 08 00 01 66.66 066.66
11.8 094 16 00 01 10 05-00.16 008.76
14.6 078 10 06 01 10 02 00.12 003.25
15.0 075 10 05 01 10 02 00.26 002.00
15,0 075 10 05 01 10 02 66.66 066.66
14.4 077 10 03 01 10 02 00.26 001.25
13.8 078 11 03 01 10 02 00.09 002.75
12.9 081 10 02 01 10 02 00.31 001.75
13.3 082 16 00 01 10 02 02.27 038.50
13.0 087 14 15 03 09 14 00,54 001.17
14.1 080 14 13 03 05 01 00,43 001.33
13.6 083 14 18 08 00 01 00.78 001.17
13.9 082 14 12 08 00 01 00,43 001.33
14.2 082 14 15 03 09 16 00.53 001.33
13.2 08'3 16 00 08 09 16-00,25 001.92
49
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
09
10
13
13
13
13
13
13
14
14
14
14
14
15
15
15
17
17
17
17
17
17
17
17
17
21
21
21
21
21
23
23
2100
1145
1240
1600
1830
2140
2230
0845
1230
1420
1815
2315
0900
1245
1500
1130
1215
1330
1400
1500
1600
1820
1945
2040
0840
1000
1200
1440
1600
2300
2300
07.114
06.530
06.481
06.456
06.369
06.371
07,260
07,259
07.264
07.262
07,245
07.400
07.472
07.465
07.451
06,508
06.473
06.387
06,377
06.334
06.312
06.186
06.177
07.342
06.068
06.070
06,098
06,138
07,629
06.769
06.769
11.3
15.1
16.6
18.5
17.6
15,4
12.2
12,8
16.4
17.6
16,5
14,9
13.9
17.0
19,5
10.1
12.2
13.6
14.5
15.5
15.8
14.9
13.7
09.6
12.5
12.6
12.9
14,5
11.4
18.7
18.7
11.0
10.8
10.5
10,3
10,8
12.1
11.8
11,7
12.0
11,8
11.0
11.8
11
3
11,5
11.9
10.7
10.6
10.9
11.2
10.6
10.5
09.8
10.2
10.3
10.2
10.1
09,5
11.1
11.0
09,9
09,9
14.2
13.6
15.4
15,6
16.1
13.9
13.9
14.3
15.5
16.3
13.9
14.2
13.1
15.0
14.1
14.6
15.0
13.1
13.3
13.4
14.1
14.3
12.2
10.6
11.3
11.2
11.8
13.3
13,4
19.0
19.0
077
080
070
068
074
098
100
092
089
081
100
100
097
083
085
034
038
042
050
060
043
039
050
068
098
099
099
098
099
040
040
14
11
11
10
10
10
10
16
10
10
16
10
16
10
12
16
12
14
14
14
14
14
16
16
16
11
16
11
11
16
16
01
06
06
01
02
02
02
01
01
01
02
02
01
01
03
07
07
13 07
02
03
05
10
07
08
07
00
08
08
00
08
00
04
06
00
02
11
12
12
07
07
07
08
07
08
02
02
02
02
08
00
00
00
02
00
02
02 02
00 08
00 08
10
07
08
10
10
10
10
10
10
10
10
10
10
10
09
05
05
05
05
06
01
00
01
00
10
10
10
10
10
00
00
02 66.66
14 05.84
14 00,49
02 00.25
12 00,87
10-00.02
10 66.66
05 00,01
02-00,05
02 00.02
10 00.17
09 00.23
05 00,55
02 00.07
02 00.14
01 09,43
01 00.35
01 00.86
01 00.10
01 00,43
01 00.22
01 01.26
01 00.09
01 66.66
06 12.74
10 00.11
10-00.28
10-00.40
10 66.66
01 08.60
01 08.60
066.66
062.75
000.91
003.33
002.50
003.17
066.66
010.25
003.75
001.83
003.92
005.00
009.75
003.75
002.25
044.30
000.75
001.25
000.50
001.00
001.00
002.33
001.42
066.66
084.00
001.33
002.00
002.66
066.66
055.00
165.00
50
APPENDIX III
Computer Program
1000 D!MENS!ONEVAPW(35) ,SWNO(35).Y(5),X( 5),EW(25),EA(25),EAVEW(65),SUM
SUMFW(24),SUMFAI24)
1AR(24),SUMTP(24),SUMTB(24),SUMTAI24),
2,AIR2(24),TPAN2(24),TBAY2(24),FW2(24),C(24),B(24),SU
SVAPB(24),FB2(24),SDIFB(24).E82(
3MAB(24),AB2(24),
SWVE L(24),WVEL2(24).
424),SUMHU(24),HUM2(24),
SSRATE(24),RAIE2(24),SCLDS(24),CLDS2(24),TMEAN(24),SDEV(2A),FA2(24)
9 FORMAT(6X,2I3,!5,F7.3,3F5.1,F4.O,5F3.0,F6a2pF7.2
100 FORMAT(1H .2(I4,2X),I6,2X,2(F8.2,2X),F7.36H CORN SF7.3)
101 FORMAT(1H1)
,F7.3.2X,F4.0)
102 FORMAT(1H 27H AVE EVAP WITH ZERO WIND
103 FORF'IAT(1H ,6HWIND ,5(F7.3,2X,F4.0))
104 FORMAT(///)
hiM TOTAL 065 ,2X.F7.2)
106 FORMAT(1H .16H AVE OF ALL. OBS .5H AIR ,F7.2,7H S 0EV .F7.2,SH HUN
F7.2.7H S 0EV ,F7.2.4HTBAY.F7.2)
1
107 FORMATC1H1)
108
109
111
113
114
115
116
117
119
120
121
122
123
124
125
FORMATI1H 14H AVE PAN TEMP .6(F7.22X))
FORMAT(1H 14H AVE BAY TEMP .6(F7.2,2X))
FORMAT(1H ,16H AVE TAIRTBAY s6(F7.22X))
FORMAT(1H ,20H AVE AIR VAPOR PRES ,6(F7.2,2X))
FORMAT(1H ,18H AVE BAY VAP PRES ,6(F7.2,2X))
FORMAT(1H øl9H AVE BAY EWAIR EA ,61F7.2,2X))
FORMAT(1H .14H AVE HUMIDITY ,6CF7.2,2X))
FORMAT(IH 20H AVE PAN VAPOR PRES ,6(F7.2e2X))
FORMAT(1H ,14H AVE WIND VEL ,6(F7.2.2X))
FORMAT(1H a17H AVE CLOUD COVER ,6(F7.2,2X))
FORMAT(1H .1OH AVE EVAP ,6(F7.3,2X))
FORMAT(IH ,I3HAVE AIR TEMP .6(F7.2,2X))
FOR EACH HOUR
FORMAT(1H 19H 8
6F6.1)
FORMAT(1H ,19H NO OF C EACH HOUR ,6F6.1)
FORMAT(1H ,14H NO OF E USED=,F6.hI
EWC 8) 7.85
EW(9) =8. 40
EW( 10)=8.98
EW( 11 )=9.60
EW(12)= 10.25
EW(13)10.95
EWI 14)=11.68
EW(1 5) =12.45
EW( 16)13.24
EW( 17)=14. 16
EW( 1B)15.07
EW( 19) = 16. 04
EWI2O)=17.06
EWI 21 )=18. 16
EW( 22 ) 19. 30
EW(23)20.61
EW( 24 ) =2 1. 77
EWI 25 )22.22
EA(8 )8.03
EA(9)8.63
51
EAt 101=9.22
EAt 11 )9.83
EAt 12 ) =10. 50
EAt 131=11.25
EM 14)=12.0
EAt
EAt
EAt
EA(
151=12,75
161=13.65
171=14.55
181=15.45
EAt 191= 16. 50
EAt 20 I =17. 55
EA(21 1=18.67
EAt 22 1 = 19. 80
EAt 24 I =22. 35
EA(23)=2 1.08
EA( 25 ) =23. 75
X (1) 5.
XC 2) =10.
X( 31=15.
X(4) =20.
XC 51=25.
Vt 11=0.000111
Y(21=0.000 165
Vt 31=0.000213
Vt 41=0,000256
V (5) =0,000296
EVAPOO.
E NONE = 0.
XWVEL=0.
XHUM'094.
XTPAN 18.8
00 3 1=1,35
1 EVAPW(11=0.
3 SWNO(1)0.
8 READ(1,9) IM0,1DATE,NHR,HEIGH,TPAN,TBAY,TA1R,HUM,WDIR,WvEL,CLDTPCL
1DAM,WTHER,DELHT ,DELHR
IF(DELHR.EQ.165.0) GO TO 2000
NHR=NHR/ 100
AWVEL C (XWVEL+WVEL 1/2.)
AHUMC (XHUM+HUM)f2.)
IWVEL=AWVEL
IHUM=AHUM
IT BAY I BAY
I TPANTPAN
ITAIRTAIR
IF C DELHR-66 .66 115 I 12 ,15
12 F0.
GO TO 18
15 DO 16 1=1.5
TF(TPAN-XI1))17,17,16
16 CONTINUE
17 F(( (TPAN-X( I_1/5.1*(YC 1-1)) )+Y( I-i)
18 TCOR(F*21.*(XTPANTPAN))
IFCWVEL-5. )19,1920
19 WCOR=O.
GO TO 30
20 IFCWVEL-17.)21.21.25
21 WCORO.4108+O.059*(WVEL_11.7)
GO TO 30
52
25 WCOR=0.9953+0.1133*(WVEL-20a076)
30 THT=HE1GH+TCOR+(WC0R/10.
IF(DELHR.GT.10.)GO TO 40
TDELH= (XTHTTHT 1* 10.
TRATETDELH/DELHR
IFCWVEL.GT.O.)GO TO 34
EVAPOEVAPO+TRATE
E N ON E = EN ON E+1.
GO TO 40
34 DO 35 1=1,35
IF(IWVELI )35,36,35
35 CONTINUE
36 FVAPW(I)=EVAPW(1)+TRATE
SWNO( I )SWNO( I )+1.
40 DO 41 1=8.25
IFUTPAN.EQ.I)GO TO 42
41 CONTINUE
42 A1
FW=HTPANA)*IEW(I+1)EW(I)))+EW(I)
DO 43 1=8,25
IF(ITAIR.EO.I)GO 1044
43 CONTINUE
44 A=I
C C IA !R_A
EA( 1+1)EAC I)) )+EACI) )
IF(DELHR.GT.10.00)GO TO 50
50 DO 51 1=1,24
IF(NHR-1 )52,52,51
51 CONTINUE
52 SUMAR(II=SUMAR(I)+TAIR
AIR2CI)=AIR2(I)+(TAIR*TAIR)
SUMIP (I) =SUMTP C I )+TPAN
TPAN2C I )=TPAN2( 1)+CIPAN*TPAN)
SUMT8(I)SUMTB( I )+TBAY
TBAY2( I )=TBAY2C I )+C TBAY*IBAY)
SIJMAB(I)=SUMAB(fl+(TAIRTBAY)
AR2( I )=AB2( I )+( (TAIRTBAY)*(TAIRTBAY))
SUMFAC I )=SUMFA( I)+FA
FA2CI)=FA2CI )+(FA*FA)
DO 55 J=8.25
IFUTBAY.EQ.J)GO TO 56
55 CONTINUE
56 AJ
FWBt(TBAYA)*CEW(J+1)--EW(J)))+EW(J)
SVAP8(I )=SVAPB( I )+FW
F82C I )=FB2 II )-i-(FW8*FWB)
SDIFB( I )=SDIFB(I )+(FWBFA)
E82( I )=EB2(I)+( CFWBFA)*(FWBFA))
57 SUMHU( I )=SUMHU( I )+HUM
HUM2( I )=HUM2( I )+(HUM*HUM)
SUMFW( I )=SUMFW( I )+FW
FW2C I )FW2( 1)+(FW*FW)
SWVEL( I )=SWVEL( I )+WVEL
WVEL2(1)=WVEL2( I)+CWVEL*WVEL)
SCLDS( I )SCLDS( I )+CLDA
CLDS2( I )=CLD$2( I )+CCLDAM*CLDAM)
B( I )=B( I 1+1.
IF(DELHR.GT.10.00)GO 10 60
SRATE( I )SRATE( I )+TRATE
RATE2 (I) =RATE2 (I) +( TRATE*TRATE)
CCI) C( I )+1.
AHUM/100.
53
60 THUM=THUM+HUM
HUMD2=HUMD2+(HUM*HUM)
SBAY=SBAY+TBAV
61 SAIR=SAIR+TAIR
ZAIR2=ZAIR2+(TA!R*TAIR)
E*E+1.
CORNTCOR +WCOR/1O,
62 WRITE(3,1OO,1MO.IDATE,NHR,FW,FA,TRA1E,cORN
63 XTHTTHT
XTPAN*TPAN
XWVL=WVEL
X H UM = H UM
GO TO 8
2000 wRrrE(3,j01)
63 EAVEO=EVAPO/ENONE
WRITE(3,102)EAVEO,ENONE
DO 67 1=1,35
!F(SWNO(I).EO.O.)GO TO 66
EAVEW( I )=EVAPW( I )/SWNO
I
GO 10 67
66 EAVEW(I)=O.
67 CONTINUE
DO 400 J1.12
DO 250 1=1.24
IF(t3( 1)-i. )240,240,201
201 GO TO (2O8,209211,213,214,215,216,217,219,220,221.222),J
208 TMEAN(I)=SUMTP(I)/B(1)
S DEV(I)=SORT( ITPAN2(I)- (SUMTP(1)*SUMTP(I) /B(I)/(8(I)-1.))
GO 10 250
209 TMEAN( I )=SUMTB( I
/B( I)
S DEV(1)=SQRTC(TBAY2(j)-((SUMTB(1)*SUMIB(I) /B(l))I/(B(I)-1.))
GO 10 250
211 TMEAN(!)=SUMAB(1)/8(I)
S DEV(I)=SORT((A82U)-( (SUMAB(I)*SUMABCI) )/B( I))I/(8(I)-1.))
GO TO 250
213 TMEANU)=SUMFA(I)/8(I)
GO 10 250
214 TMEAN(I)=SVAPB1)/B( 1)
S DEV(I)=SQRT((F82(I,-USVAPB(I)*SVAPB( 1))/8( fl))/(B(I)-1.))
GO 10 250
216 TMEAM(I)=SUMHU(1)/B(I)
S DEV( I )=SQRTI (HUM2( I -1 (SUMHU( I )*SUMHU( I) )/B( I)) )/(B( 1)-i.))
GO 10 250
217 TMEANU)zSUMFWU)/B(I)
S DEV( )=SQRT( (FW2( 1)-I (SUMFW( I )*SUMFW( 1) I/B( I)
11(8(1 I-i.)
GO 10 250
215 TMEAN(1)=SDIFB(I)/8(I)
SDEV(I)=SOR1((EB2(I)((SDIFB(I)*SD1FB(1)1/B(I)))/(B(I,_j,,)
GO 10 250
219 IMEAN(I)=SWVEL(I )/B(I)
S DEV(1) =SORT((WVEL2U)-((SWVEL(I)*SWVEL(j))/B(!)))/(B(j)_1.)
GO 10 250
220 TMEAN(j)=SCLDS(I)/B(t)
S DEVI fl=SQRT( (CLDS2( I )-( (SCLDS( I)*SCLDS( 1) )/B( Ill )/(B( I )-1.) I
G010250
221 TMEAN(I)=SRATE(I)/B(I1
S DEV(1)=SQRT((RATE2U)-((SRATE(1)*SRATE(I))/Cti) ))/(C(I)-1.) I
GO TO 250
54
222 TMEAN( I )=SUMAR( I )/B( I)
& DEVII)zSQRTI(AIR2II)I tSUMAR(I)*SUMAR(I))/5(I)))/(PtI)-1.))
GO 10 250
240 TMEANU)=0.
S DEVU)0.
250 CONTINUE
GO TO (308,309,311,
313,314.315.31,317.319,32O.321i322)J
308 WRITE(3,108)(TMEAN(!),SDV(I),Ia1,24)
GO TO 400
309 WR!TE(3,109)(TMEAN(!),SDEV( I),I,24)
GO 10 400
311 WRITE(3,111)(TMEAN( I ),SDEV( I),I-1.24)
GO TO 400
313 WRITE(3.113)(TMEAN(I),SDV( I),I1.24)
GO TO 400
314 WRITE(3,114) (IMEANI I) .SDEV( I) .1-1.24)
GO TO 400
315 WRITE(3,115)(TMEAN(I).SDEV( I),I*1,24)
GO 10 400
316 WRITE(3,116)(TMEAN(I) 'SDEV( 1)01*1,24)
GO TO 400
317 WRITE(3,117)(TMEAN(I),SDEV( 1)0121,24)
GO 10 400
319 WRITE(3,119)(TMEAN(I ),SDEV(I),I=1,24)
GO TO 400
320 WR!IE(3.120)(TMCAN(!),SDEV( 1)0121,24)
GO TO 400
321 WRITE(3,121)(TMEAN(I) ,SDEV(t),Iz1,24)
GO TO 400
322 WRITE(3,122)(TMEAN( I)SDEV( 1)01*1,24)
400 CONTINUE
81 FTAIR=$AIR/E
VDAIR=SQRT((ZAIR2((SAIR*SAIR)/E))/(E-1.))
FHUM=THUM/E
VDHUM=SORT (HUMD2 ( (THUM*THUM) /E) ) / (Ci .0))
FTf3AY=S!3AY/E
82 WRITE(3,103)(EAVEWU),SWMO( I),11.,35)
WR tIE 'C 3, 104
WR ITE( 3, 106) FlAIR . VDAIR. FHUM . VDHUM, FTBAY
WRITE (3,107)
WRITE(3o123) (6(I)' 11,24)
WRITE( 3,124) (CC I), 1=1,24)
WRITE(3,125)E
STOP
END