Hi Rudi,
I really like your approach of combining historical observations and reports with
modern satellite images! That´s a very good idea and will make the chapter very well
readable!
You have a large number of color images. While a few can hopefully be
accomodated, please try to supply the others in B&W. For instance, Figures 1, 6, and 7
would likely be as good in B&W. In some cases, it may also be possible to arrange a few
color panels in a single plate. I leave that up to you, but currently I fear that Springer
would not like to print as many color figures. I cannot be more definite at the moment, as
I have to wait how many images we will have in total.
Perhaps one could also mention the role of dust as a nutrient source, for instance for
the Amazon.
Perhaps at the end you could also address what is missing to date: for instance,
incorporation of dust into weather forecast models could improve the forecasts,
incorporation into climate models may yield insight into possible feedback mechanisms
between climate change and dust generation/transport.
A few typos are corrected in your text below. I am looking forward to receiving your
next draft!
Kind regards,
Andreas
Chapter draft for the book (030706)
Intercontinental Transport of Air Pollution
A. Stohl, Ed, Springer, 2004
Intercontinental Transport of Dust:
Historical and Recent Observational Evidence
Rudolf B. Husar
Center for Air Pollution Impact and Trend Analysis (CAPITA)
1
Washington University, St. Louis, MO, rhusar@me.wustl.edu
Introduction
The intercontinental transport of anthropogenic pollutants is a recent topic of
scientific inquiry. The long-range transport of dust has been recognized and studied for at
least a century from many perspectives using a variety of scientific analysis tools.
From the point of a geologist, wind is one of the geological agents that shape the
surface of the Earth. Agronomists view wind blown dust as the means of delivering plant
nutrients to the fields or as a process that erodes the fertile soil. For oceanographers, dust
is also a critical nutrient. Atmospheric scientists study dust because of its influences on
the Earth’s radiative balance both directly and indirectly through cloud modification.
Finally, from the point of air pollution, dust is just one component of the pollutant mix
that affect human health, reduces human or electronic vision and causes other effects to
human welfare. In many of these fields, particularly geology and agronomy, extensive
quantitative literature exist on long-range dust transport, some dating back to 1800s. For
the early literature on dust, this review relies on the admirable reviews by Free, (1911)
and Kempf (1914.
Skipping about 100 years, the 1990s were the beginning of the global-scale
observational revolution. Remote sensing by a multitude of satellites, along with the
growth of surface monitoring networks (Holben, 1998) now allow daily global-scale
monitoring of dust emissions, transport and the analysis of spatio-temporal patterns.
Operational simulation models are that forecast the dynamic dust emissions and the
resulting pattern of concentrations and depositions on regional or global scale (Westphal
??, Nickovic et al., 2001). Both the satellite/network monitoring data, as well as the
model forecasts are now posted on the internet and conveniently accessible to the
interested research community. In fact, over the recent years, real-time observation on the
onset, evolution, transport and long-range impact of aerosol events has become major
topic connecting the global atmospheric science communities through the internet. (Husar
et al., 2001; Prospero ??).
This brief review of long-range dust transport deals with the old and the new events.
It pays tribute to the old literature (prior to 1910) which contains many of the original
scientific observations and the explanations. This review also uses the most recent (post
1990 observational evidence from satellites, mainly as a graphical illustration of the
phenomena reported by the ‘old timers’. This selective treatment essentially ignores the
immense high-quality research contributed during much of the twentieth century. For that
literature readers are directed to several summary monographs and review articles
[Ref???].
Intercontinental Transport Analysis Framework
Trans-continental source receptor relationships (SSR) are governed by the same
natural processes as local-scale source-receptor relationships. The concentration at a
receptor site Cj is related to the emissions at location j (NOT i???), Ei through the
transfer matrix Tij. Quantification of SSR requires a full understanding of all three classes
of parameters. The indices i and j represent the quantized spatial distribution of these
parameters. All three parameters also depend on time on various scales: secular (over 10
years), seasonal, synoptic (3-10 days) and diurnal. The transfer matrix Tij represents the
fraction of the emission from source i that arrives at or is deposited at receptor j. Tij
2
incorporates the roles of atmospheric transfer processes including horizontal and vertical
dilution, chemical or physical transformations, as well as dry and wet removal.
For aerosol species such as wind blown dust, SSR can be established either by source
oriented dispersion models or by receptor oriented tracer methods. While tremendous
progress has been made applying both techniques, a robust quantification of
intercontinental dust transport dynamics is still a major challenge.
Global Dust Emissions
The origin of atmospheric dust was a hotly disputed issue in the 17th-18th centuries
(see Husar et al., 2001). However, by the late 19th century it was established ‘beyond
doubt’, that dust emissions and long-range transport occurs when dry sandy surfaces are
exposed to strong winds (Free, 1911; Kempf, 1914). Not unreasonably, Hann (1906)
refers to the haze due to windblown dust as ‘mechanical turbidity’ (mechanische
Truebung) since it is caused by mechanical forces. Early explorers also recognized that
the Sahara and Gobi deserts are the main sources of atmospheric dust.
Turning to modern evidence. Figure 1 shows the continental map of surface
roughness derived from the NSCAT scatter meter (NOT scatterometer?)(3 cm
wavelength). The low roughness areas (red and yellow) are indications of the sandy
surfaces of sand dunes (or ice sheets). The majority of the sandy regions are over the
Sahara Desert, Arabian Peninsula, Kazakhstan as well as over the Taklamatan and Gobi
deserts in Asia.
The dust source regions that contribute most to the trans-continental transport are the
Sahara desert in North-West Africa and the Gobi desert in East Asia. Further discussion
on large-scale dust transport pattern is given in the Sahara and Gobi dust event sections
below. The current global estimates for the spatio-temporal pattern and the magnitude of
dust emissions are uncertain for a number of reasons. [Need a statement on current
global dust emission estimates, references, Prospero (xxx)].
3
Figure 1.Spatial distribution of sand dunes based on radar ‘backscatter’ from satellite data.
Needs better explanation of what is shown. What is the scale?
Horizontal and Vertical Transport
The winds that lift the dust particles from the surface arise either from synoptic-scale
pressure fields (1,000 km, 3-5 days) or from local orographic effects. The thermal winds
driven by the surface heating are diurnal and much smaller in scale. Satellite and
photographic observations show that near the source, dust clouds have two distinct
pattern. Dust plumes resemble pollution or smoke plumes where the particulate matter is
emitted from a small point source and dispersed horizontally and vertically as a coneshaped plume by the intense turbulence of the dust storm. The second near-source dust
pattern is the dust front. At the leading edge of the advancing dust ‘wall’, the dust
immediately rises to high elevations, ready for long –range transport. The synoptic,
micrometeorological and dust-suspension mechanisms associated with the two dust storm
patterns are not well understood [does anyone know? Do the dust models reproduce these
differences? When does the dust rise to the free troposphere?]
Figure 2. Near-source dust emission patterns: a.) dust plumes dispersing from near point
sources; b.) dust front.
4
Dust outbreaks are intermittent, ranging from about 5-10 day periodicity to rare
occurrences. Many of the outbreaks resemble fluid jets forcefully injected into a
quiescent environment. Interestingly, the visualization of these peculiar atmospheric flow
patterns by the dust particles (Figure 3a and 3b) reveals that similar ‘dust jets’ also occur
on Mars [Yes, that´s a nice comparison!keep it??].
Figure 3, Dust outbreaks resembling jets over West Africa (February 2001) and over Mars.
The trans-Atlantic transport of Sahara dust is riding on the persistent zonal
Westerlies, just north of the Inter-Tropical Convergence Zone (ITCZ). [need more?
Covered elsewhere? There´s a little in the chapter by Cooper, but as his chapter was to
long, I have asked him to shorten his excursions on dust transport, such that this will
likely be removed from his chapter].
A key aspect of intercontinental dust transport is the vertical distribution of the
emitted dust layer. Dust transport within the boundary layer is subject to dry and wet
removal processes. Removal is particularly efficient in shallow marine boundary layers.
It has been recognized that if dust is raised into the upper air, “velocities and distances of
transfer are much greater, not alone on the account of grater vertical fall but because of
the greater velocity of the air currents at higher altitudes” (Free, 1911). Hence, it is
unlikely that intercontinental dust transport can occur at elevations below 1-2 km. Rather
trans-continental dust transport occurs mainly in free troposphere at 2-10 km elevation
where the transport is swift and cloud removal processes are weak.
The recent LITE lidar data from the Space Shuttle (Figure 4) clearly illustrates that
the dust transport from the Sahara to the Americas occurs in an elevated layer above the
scavenging boundary layer. Vertical soundings from diverse set of instruments (Lidar,
aircraft soundings) confirms the prevalence of long-range dust transport in elevated
layers [refs needed Tratt, Murayama et al.,1998, Winker].
5
Figure 4. Vertical distribution of Sahara dust in the Atlantic trade winds above the marine
boundary layer. [Winker ref]
Transformation Processes.
The main transformation process affecting dust during long range transport is the
loss of large particles by gravitational settling. According to Stockes’ NOT Stokes´???
formula the settling velocity of a particle “will vary as the square of the diameter; or
inversely, the radius of the particle which the wind can support (the radius of
competence) will vary as the square root of the velocity” (Free, 1911). Based on his own
experiments, Udden (1898) concluded that the average largest size of quartz particles that
can be sustained in the air by strong ordinary winds is about 100 µm in diameter.
As Free (1911) notes, “There is a small fraction of airborne dust which is fine
enough to remain more or less permanently in suspension…and the distances covered by
such material are consequently very great, though well established instances are rare on
account of the difficulty of determining the source of the material. Examination of the
dust itself fails to indicate the place of origin and one must rely on indirect evidence such
as meteorological data”. Occasionally evidence for the transport distance is furnished by
tracing the path of a storm by observations made along the path. Udden (1896) in his
examination of western US dust storms records observable dust transport distances of at
least 400 miles.
The lifetime and transport distance of intercontinental dust (1-10 m) is determined
largely by the wet removal processes in clouds and rain. Hence, the transport distance of
emitted dust is strongly influenced by the water cycle. Recently developed microwave
sensors on polar satellites measure both the columnar water vapor concentration as well
as the precipitation rate over the oceans. The ratio of these parameters yields the
characteristic atmospheric life-time of water vapor which is relevant to the dust removal.
The oceanic spatial pattern of the precipitation/water vapor ratio P/W [hr-1] is depicted in
Figure 5. The maps show more than an order of magnitude variation in the water removal
rate ranging from 0.002 to over 0.02 hr-1. This corresponds to water residence times
between 2-20 days.
In the northern hemisphere precipitating cloud systems emanate from both North
America and East Asia. The narrow belt of high removal in the equatorial Pacific and
Atlantic is the inter-tropical convergence zone. The lowest water removal rates can be
6
observed over the subtropical oceans in both hemispheres with water life times exceeding
20 days. Both water vapor and the chemical species are transported through these regions
without appreciable wet removal.
The implication of the observed water removal rate climatology is that it spatially
modulates the concentration pattern of dust: high water removal areas will result in low
ambient dust concentrations due to wet scavenging. Another implication is that the dust
deposition and concentration pattern may occupy complementary spatial domains.
Overall, the strong heterogeneity of water residence time contributes to the spatial
‘lumpiness’ of the global dust concentration and deposition pattern.
Figure 5. Water residence time isn´t 1/t shown??? derived from satellite data over the oceans.
Recent size distribution data show that the mass of long-range transported dust is
virtually all in the sub-10 m diameter range. On the other end, the emitted dust mass is
all above about 1 m since strong molecular forces prevent the mechanical dispersion of
sub-micron particles. As a consequence, the long-range transported dust mass distribution
is in the 1-10 m diameter range, with a mass mode in the 3-5 m range. This size
selective sorting and the remarkably uniform grain of eolian dust deposits have been
pointed out by Udden (1898).
7
Figure 6. Typical size distribution of local and long-range transported dust. Better explain
which curves are shown
The basic mechanisms governing the dust suspension by frictional forces of the
winds have been studied since the late 1800s (e.g. Free 1911). Modern dust models
(Westphal ??; Nickovic et al., 2001) use these mechanisms along with the
wind/precipitation pattern from meteorological models to simulate or forecast the dust
emissions.
Early microscopic examination of the dust itself suggested a desert origin as it
consists of “very fine splinters‘ of quartz and still finer clay-like dust often gathered into
flocks of aggregates, which is probably the final debris from the disintegration of the
feldspathic and similar minerals. The reddish color is probably due to ferruginous matter”
(see Free, 1911, pp 93). Figure 7a shows a modern electro micrograph of dust particles
(Levin ???)
Figure 7a. Dust shape (Levin, ???). b. Composition (Barac, 1901)
The early chemical composition data on the sirocco perhaps explain sirocco? dust
collected at various locations (an example is shown in Figure 7b) was “in perfect accord
with the Saharan hypothesis due to the similarity with the Sahara dust collected in
Tunis”.
Some of the modern dust chemical composition data can distinguish various dust
sources by the fine structure of their respective chemical composition. The new data also
show that the chemical composition of the particles measured thousands of km from the
source changes very little during multi-day transport Husar et al. (2001). However, some
measurements show that dust particles are often coated with sulfate, particularly in
polluted regions such as the Mediterranean. Cloud processes (gas scavenging and liquid
phase oxidation of SO2) is responsible for the sulfate coating. However, sulfate is also
found on the dust particles that have not passed through clouds. (Wurzler et al., 2002).
Global Dust Concentration Climatologies
The global distribution of atmospheric aerosol including wind-blown dust could not
be determined by the early researchers. However, by the 1990s satellite remote sensing
allowed the creation of global aerosol climatologies based on back scattering properties
8
measured by the AVHRR sensor, e.g. Husar et al. (1997) and absorbing properties
obtained from the TOMS sensor, Herman et al. (1997). Since then several other global
aerosol climatologies have been reported. The aerosol maps derived from the POLDER
sensor use the aerosol polarization. The climatology derived by the MISR sensor uses
angular backscattering data. The aerosol climatology by the MODIS sensor utilizes
spectrally and spatially resolved sensors to derive the aerosol maps from the reflectance
data [need references]. I think this paragraph needs more explanation
All these satellite sensors produce columnar integrals of the aerosol at a given
location. The aerosol maps derived from the MISR and TOMS sensor are shown in
Figures 8 and 9. Figure 10 depicts the global continental climatology derived from
surface visibility observations obtained at over 10,000 meteorological stations. The
visibility maps yield the spatial pattern of the horizontal extinction coefficient.
Virtually, all the aerosol mapping sensors are different and respond to different
aspects of the six dimensional aerosol system (x,y,z,t, particle size, composition). Thus,
they can be considered complementary, rather than redundant characterizations of the
global aerosol pattern.
[Here will be a qualitative description of the global climatological dust pattern
depicted by the different sensors. Satellite-satellite comparisons?? Model-data
comparisons ??, not yet]
Figure 8. Seasonal global aerosol distribution derived from the MISR sensor (vertical aerosol
optical thickness, AOT)
9
Figure 9. Global aerosl pattern (absorbing aerosol index) derived from the TOMS sensor.
Figure 10. Seasonal aerosol pattern (horizontal extinction coefficient} derived from surface
visual range observations (Husar et al., 2000).
Documented Intercontinental Dust Transport Events
Dust Transport Events in Europe
Intercontinental dust transport is highly episodic. Much of the scientific
understanding has been learned by analyzing specific dust events in detail.
10
Figure 11. Sahara dust pall over Great Britain and France based on SeaWiFS sensor.
Figure 11 shows a recent Sahara dust incursion to northern Europe recorded by the
SeaWiFS satellite. A thick yellow dust cloud is seen over England and France. Forecast
models (Westphal ??? Nickovic ??) show that the dust source was over N. Africa. This
episode has not been analyzed in the current literature However, it strongly resembles the
February 1903 dust fall episode that was well documented by the contemporary literature,
exactly 100 years ago. The event was described by Herrmann (1903), Hellman (1903)
Mill and Lempfert (1904), Vanderlinden (1903).
The 1903 February 21-22 dust event impacted northern Europe including southern
England, northern France, Holland, Germany and Denmark. Airmass history analysis of
this event indicates that the Sahara dust reached northern Europe through a loop over the
Atlantic, which was consistent with the absence of excess dust in southern Europe. Also,
consistent with the looping trajectory is that the dust arrived to England half a day before
it reached Germany. According to Herrmann (1903) “the European dust storm of
February 1903 seem to have traveled mainly in the higher strata and with a velocity of 50
mi/hr”. Microscopic analysis of the February 1903 dust fall was also consistent with its
desert origin.
The most analyzed Sahara dust transport event to Europe occurred in March 1901. It
was chronicled in an admirable monograph by Hellmann and Meinardus (1901), Valentin
(1902), Vanderlinden (1901) and dozens of other researchers.
For the early researchers the most conclusive evidence regarding the Sahara origin of
the sirocco dust was derived from the meteorological sources. Using the measured
pressure fields they were able to map the trajectory of several dust bearing storms and
tracing them back to a point of origin in northern Africa. In a remarkable analysis, back
trajectories were calculated for both sea level and at 2500 m which clearly show the path
of the dust cloud from Sahara to Central Europe. Hellman and Meinardus (1901) report
that a part of the dust storm of March 11, 1901 got elevated into higher strata, above the
11
zone of rain formation at 1-2 km. Three days later, it had sunk low enough to be caught
by the rain of the 15th and carried down there with (Krebs, 1903).
The early researchers have also performed detailed dust deposition flux analysis. The
dust fall data for the March 1901 event were collected at various locations in Europe,
and ranged between 1 and 11 g/m2. Of particular interest is the preparation of maps
showing the geographic distribution of dust fall over Europe. The dust fall values were
largest in southern Europe and decreased toward the north. From the figures of Hellmann
and Meinardus (1901) the European area covered with dust was 440,000 km2, while the
total estimated dust fall amount was about 1.8 Tg. The resulting deposition flux average
for the event was 4.8 g/m2. At the specific gravity of 2 UNIT! this corresponds to a dust
layer of 0.24 mm thick. Free (1911) speculates that if storms comparable to the March
1901 event would occur every five years, the dust layer thickness would be 4.8 mm per
century. It would be interesting to compare these early estimates of Sahara dust
deposition to the values derived from modern tools.
Perhaps this section should be started with the following two paragraphs!
The first known scientific description is that of Wendelin (1646). Ehrenberg has
listed 340 dust events occurring prior to 1847 and updated the list with another 193
occurrences in 1870. In the bibliography of Eolian Geology by Stuntz and Free, 1911
articles by over 120 different researchers were cited regarding European falls of sirocco
dust between 1870 and 1910.
Early trend analysis of the Sahara dust events occurring between 1782-1898 has
shown a tendency for the dust falls to occur most frequently in those years when the
Sahara is the driest (Krebs, 1903). His dates for the dry years in the Sahara were
calculated from Bruckners drought index.
Transport of Asian Dust
The most notorious Asian dust storms originate from the Gobi Desert. The
transcontinental transport of Asian dust is carried eastward by the Northern -Pacific
‘conveyor belt’. The main features of the springtime transport pathways from Asia are
examined elsewhere in this book. [Cooper, perhaps Schultz and Bey??]
Meteorological records of visibility and dust-falls, indicate that over China and
Korea dust events have occurred throughout the thousands of years of recorded history.
Typical western reports of east Asian dust transport are found in ship logs: “On April 2,
1892 there fell on a ship 95 miles west of Nagasaki a yellow dust which must have come
from the interior of China and have been carried by the wind to the place where it was
observed, a distance of at least 1000 miles.” (Milne, 1892).” A similar dust transport was
reported by Pumpelly (1879)”. There are also several reports that the Australian dust
storms have reached New Zealand, a distance of about 1500 miles. e.g Marshall (1903),
Chapman and Grayson (1903).
Compelling geological evidence of global scale transport of Asian dust arises from
the chemical analysis of samples in the Greenland ice core and Hawaiian soils. The
chemical and radiological fingerprints of deposited dust at both locations were most
consistent with the composition of the Asian dust sources.
The transport events of desert dust from Asia to the North Pacific atmosphere is well
documented [e.g. Shaw, 1980; Duce et al., 1980; Parrington et al., 1983; Uematsu et al.,
12
1983; Merrill et al., 1989; Bodhaine, 1995; Husar et al., 1997] and results in a maximum
in aerosol loading each spring.
A particularly vivid illustration of trans-Pacific transport of Asian dust was reported
by an international group of investigators (e.g. Husar 2001). On April 15 and 19 1998,
two intense dust storms were generated over the Gobi Desert by springtime cold low
pressure systems descending from the northwest. The dust was detected and its evolution
followed by it’s yellow color on SeaWiFS satellite images, routine surface-based
monitoring and through serendipitous observations. (Figure 12) . The April 19 dust cloud
crossed the Pacific Ocean within 5 days, subsided to the surface along the mountain
ranges between British Columbia and California and impacted severely the optical and
the concentration environment of the region. Over Asia, the dust clouds increased the
albedo over the cloudless ocean and land by up to 10-20% but it reduced the near UV
cloud reflectance, causing a yellow coloration of all surfaces. Over the North American
west coast, the dust layer has increased the spectrally uniform optical depth to about 0.4,
reduced the direct solar radiation by 30-40%, doubled the diffuse radiation and caused a
whitish discoloration of the blue sky. On April 29, the average excess surface-level dust
aerosol concentration over the valleys of the West Coast was about 20-50 µg/m3 with
local peaks >100 µg/m3. (Figure 12). The dust mass mean diameter was 2-3 µm and the
dust chemical fingerprints were evident throughout the West Coast and extended to
Minnesota. The April 1998 dust event has impacted the surface aerosol concentration 2-3
times more then any other dust event since 1988.
Figure 12. Interestingly, in April 2001, another Asian dust transport event was even more
significantly impacting on North America. The analysis of that event named the ‘The Perfect Dust
Storm’ is in progress. Inappropriate caption.
13
[If needed, a lot more stuff can be added on dust events. Feedback and suggestions
are is most welcome. I just wanted to make sure that the old literature is well covered.]
Summary and Conclusions
The estimation of intercontinental dust transport has a rich history, interesting
present and a very promising future. Quantitative estimates based on solid observations
begun a century ago. Presently, the combination of source-transport oriented
observations using satellites and chemical fingerprinting at receptor in combination with
dynamic models provide powerful tools for documenting intercontinental dust transport.
Still, a full quantitative source-receptor relationship for transcontinental transport of
dust is not in hand. A particularly nagging problem is the estimation of the dust emission
rates. A prudent symbiotic combination of observation and model-based approaches and
global-scale scientific collaboration may accelerate progress. It is hoped that over the
next decade, both the climatological and short-term characterization of long-range dust
transport will be advanced to a satisfactory level by the collaborating global atmospheric
research community.
References
Barac M., The red dust of March 1901. Mon. Wea. Rev. July 1901, 316-317 (1901).
Bodhaine B. A., Aerosol absorption measurements at Barrow, Mauna Loa and the South Pole, J.
Geophys. Res., 100, 8,967-8,975 (1995).
Chapman F. and H.J. Grayson, On “red rain” with special reference to its occurrence in Victoria.
With a note on Melbourne dust, Vict. Nat. 20, 17-32, 42 (1903) (cited in Free, 1911 and Stuntz
and Free, 1911).
Duce R. A., C. K. Unni, B. J. Ray, J. M. Prospero, and J. T. Merrill, Long-range atmospheric
transport of soil dust from Asia to the tropical North Pacific: Temporal variability, Science, 209,
1522-1524 (1980).
Ehrenberg C. G. Uebersicht der seit 1847 fortgesetzten Untersuchungen ueber das von der
Atmosphaere unsichtbar getragene reiche organische Leben, Abhk. Presuss.Akad. Wiss Berlin
1-150 (1871) (cited in Free, 1911 and Stuntz and Free, 1911).
Free E.E., The Movement of Soil Material by the Wind, U.S. Department of Agriculture, Bureau
of Soils, Bulletin No. 68, (1911).
Hann J., Lehrbuch der Meteorologie, Vienna (1906). (cited in Free, 1911 and Stuntz and Free,
1911).
14
Hellmann J.G.G. and W. Meinardus, Der grosse Staubfall vom 9. bis 12. Maerz 1901 in
Nordafrika, Sued- und Mitteleuropa, Abh K. Preuss Met. Ins. 2 (1) 93 (1901) (cited in Free,
1911 and Stuntz and Free, 1911).
Herman, J. R., P. K. Bhartia, O. Torres, C. Seftor, and E. Celarier, Global distribution of UVabsorbing aerosols from Nimbus 7/TOMS data, J. Geophys. Res., 102, 16911-16922 (1997).
Herrmann, E., Die Staubfaelle vom 19.bis 23. Februar ueber dem nord-atlantischen Ozean,
Grossbritannien und Mitteleuropa, Annallen Hydrog. 31, 475-483 (1903) (cited in Free, 1911
and Stuntz and Free, 1911).
Husar R.B., J.M. Prospero and L.L. Stowe, Characterization of Tropospheric Aerosols
over the Oceans with the NOAA Advanced Very High Resolution Radiometer Optical
Thickness Operational Product, J. Geophys. Res. 102, D14, 16889-16909 (1997).
Husar R. B., J. D. Husar and L. Martin, Distribution of continental surface aerosol
extinction based on visual range data,
http://capita.wustl.edu/CAPITA/CapitaReports/GlobVisIGAC/AEGlobVisHTM.htm)
Atmos. Environ. 34, 5067-5078 (2000).
Husar, R. B., D. M. Tratt, B. A. Schichtel, S. R. Falke, F. Li D. Jaffe, S. Gassó, T. Gill, N. S.
Laulainen, F. Lu, M.C. Reheis, Y. Chun, D. Westphal, B. N. Holben, C. Gueymard 1 I.
McKendry, N. Kuring, G. C. Feldman, C. McClain, R. J. Frouin, J. Merrill, D. DuBois, F.
Vignola, T. Murayama, S. Nickovic, W. E. Wilson, K. Sassen, N. Sugimoto, W.C. Malm, The
Asian Dust Events of April 1998. (http://capita.wustl.edu/Asia-FarEast/) J. Geophys. Res.,
106(D16), 18317-18330 (2001).
Holben, B N., T. F. Eck, I. Slutsker, D. Tanre, J.P. Buis, A. Setzer, E. Vermote, J. A. Reagan, Y.
J. Kaufman, T. Nakajima, F. Lavenu, I. Jankowiak, and A. Smirnov, AERONET-A federated
instrument network and data archive for aerosol characterization, Remote Sens. Environ., 66, 116, 1998
Kempf, N. Die Enwicklung der Theorien ueber den Hoehenrauch, Doctors Dissertation vor der
Kgl. Technischen Hochschule zu Muenchen, Verlag von F.C.W. Vogel, Leipzig (1914).
Krebs W. Zur Grage der Staubenfaelle im Maer 1901, Annallen Hydrog. 31, 174-175, (1903)
(cited in Free, 1911 and Stuntz and Free, 1911).
Krebs W., Staubfaelle, Blutregen, Blutschnee, Globus 84, 183-184 (1903) (cited in Free, 1911
and Stuntz and Free, 1911).
Levin Z ???
Marshall P., Dust storms in New Zealand, Nature 68, 223 (1903) (cited in Free, 1911 and Stuntz
and Free, 1911).
Mill H. R. and R.G.K. Lempfert, The great dust fall of February, 1903 and its origin {discussions
of Curtis and others} Quart.Jour. Roy. Met. Soc/30, 57-91 (1904) (cited in Free, 1911 and
Stuntz and Free, 1911).
Milne J., A Dust Storm at Sea, Nature, 46, 128 (1892) (cited in Free, 1911 and Stuntz and Free,
1911) (cited in Free, 1911 and Stuntz and Free, 1911).
Merrill J. T., M. Uematsu, and R. Bleck, Meteorological analysis of long range transport of
mineral aerosols over the North Pacific, J. Geophys. Res., 94, 8584-8598 (1989).
Murayama, T., N. Sugimoto, I. Matsui, K. Arao, K. Iokibe, R. Koga, T. Sakai, Y. Kubota, Y.
Saito, M. Abo, N. Hagiwara, H. Kuze, N. Kaneyasu, R. Imasu, K. Asai, and K, Aoki, Lidar
network observation of Asian dust in Japan, Proc. SPIE, 3504, 8-15 (1998).
Nickovic, S., G. Kallos, A. Papadopoulos, O. Kakaliagou, Model for prediction of desert dust
cycle in the atmosphere, J. Geophys. Res., 106(D16), 18113-18129 (2001).
15
Parrington, J. R, W. H. Zoller, and N. K. Aras, Asian dust: Seasonal transport to the Hawaiian
Islands, Science, 220, 195-197, 1983.
Prospero
Pumpelly R., The relations of secular rock-disintegration to loess, glacial drift and rock basins,
Amer. Jour. Sci., (3) 17: 133-144 (1879). (cited in Free, 1911 and Stuntz and Free, 1911).
Shaw, G.E., Transport of Asian desert aerosol to the Hawaiian Islands, J. Appl. Met., 19, 12541259, 1980.
Sokolik IN, Winker DM, Bergametti G, Gillette DA, Carmichael G, Kaufman YJ, Gomes L,
Schuetz L, Penner JE. Introduction to special section: Outstanding problems in quantifying the
radiative impacts of mineral dust, J. Geophys. Res., 106(D16), 18015-18027 (2001).
Stuntz S.C. and E.E. Free, Bibiliography of Eolian Geology, Department of Agriculture, Bureau
of Soils, Bulletin 68 (1911).
Tratt DM, Frouin RJ, Westphal DL April 1998 Asian dust event: A southern California
perspective J. Geophys. Res., 106(D16), 18371-18379 (2001).
Tratt, D. M., and R. T. Menzies, Recent climatological trends in atmospheric aerosol backscatter
derived from the Jet Propulsion Laboratory multiyear backscatter profile database, Appl. Opt.,
33(3), 424-430, 1994.
Uematsu, M., R. A. Duce, J. M. Prospero, L. Chen, J. T. Merrill. and R. L. McDonald, Transport
of mineral aerosol from Asia over the North Pacific Ocean, J. Geophys. Res. 88, 5343-5352,
1983.
Udden, J.A, Dust and Sand Storms in the West, Pop. Sci. Mon., 49, 655-664 (1896) (cited in Free,
1911 and Stuntz and Free, 1911).
Udden, J.A., The Mechanical composition of wind deposits, Augustana Library Publications 1,
(1898) (cited in Free, 1911 and Stuntz and Free, 1911).
Vanderlinden E. La pluie de poussiere des 21 et 22 fevrier 1901. Ciel et terre, 22, 257-262 (1901)
(cited in Free, 1911 and Stuntz and Free, 1911).
Valentin J. Der Staubfall vom 9. bis 12. Maerz 1901, Sitzunsb. Kaiserl. Akad. Wiss. Vienna 111,
II a, 727-776 (1902) (cited in Free, 1911 and Stuntz and Free, 1911).
Wendelin G. Pluvia pupurea bruxellensis, Bruessel, (1646) (cited in Free, 1911 and Stuntz and
Free, 1911).
Westphal, D. L., Real-time applications of a global multi-component aerosol model. Submitted
for publication in J. Geophys. Res., 2000
Winker
An overview of LITE: NASA's lidar in-space technology experiment Winker DM, Couch RH,
McCormick MP PROCEEDINGS OF THE IEEE 84 (2): 164-180 FEB 1996
or
Anderson TL, Charlson RJ, Winker DM, et al. Mesoscale variations of tropospheric
aerosolsJ ATMOS SCI 60 (1): 119-136 JAN 2003
Yin Y, Wurzler S, Levin Z, Reisin TG, Interactions of mineral dust particles and clouds: Effects
on precipitation and cloud optical properties, J. Geophys. Res., 107 (D23) 4724 (2002).
Wurzler et al., 2002
Royal Society, The Eruption of Krakatoa and subsequent phenomena. Report of the Krakatoa
Committee, G.J. Symons, (Ed.), Harrison and Sons, Truebner & Co., London, 1888.
16
Noble A., Dust in the Atnosphere during 1902-1903, Mon. Weath. Rev., 32, 364-365 (1904) (cited
in Free, 1911 and Stuntz and Free, 1911).
17