Ephemeral lakes and desert dust sources

[1] The processes that determine which areas are strong sources of mineral aerosols are not well known. In this study we consider the role of ephemeral lakes in modulating emissions of atmospheric mineral aerosols. We focus on two ephemeral lake regions that have been identified as source regions: the zone of Chotts in Tunisia and Algeria, and Etosha Pan in Namibia. Comparisons of satellite retrieved inundation data and the TOMS absorbing aerosol index suggest that during some periods of inundation, desert dust loadings are reduced. There is some indication that after flooded areas have dried there is increased dust loading. However, the role of the inundated ephemeral lake compared with nearby regions in modulating desert dust sources is unclear, in addition, problems with interpreting the TOMS AI make conclusions difficult. More research is required to understand the small-scale sources of atmospheric desert dust in dry, unvegetated, topographic lows. INDEX TERMS: 0305 Atmospheric Composition and Structure: Aerosols and particles (0345, 4801); 0315 Atmospheric Composition and Structure: Biosphere/atmosphere interactions; 1615 Global Change: Biogeochemical processes (4805); 1655 Global Change: Water cycles (1836); 3360 Meteorology and Atmospheric Dynamics: Remote sensing. Citation: Mahowald, N. M., R. G. Bryant, J. del Corral, and L. Steinberger, Ephemeral lakes and desert dust sources, Geophys. Res. Lett., 30 (2), 1074, doi:10.1029/2002GL016041, 2003.

[1]  C. Birkett,et al.  Synergistic Remote Sensing of Lake Chad: Variability of Basin Inundation , 2000 .

[2]  Robert G. Bryant,et al.  Investigation of flood inundation on playas within the Zone of Chotts, using a time-series of AVHRR , 2002 .

[3]  P. Bhartia,et al.  Derivation of aerosol properties from satellite measurements of backscattered ultraviolet radiation , 1998 .

[4]  O. Torres,et al.  ENVIRONMENTAL CHARACTERIZATION OF GLOBAL SOURCES OF ATMOSPHERIC SOIL DUST IDENTIFIED WITH THE NIMBUS 7 TOTAL OZONE MAPPING SPECTROMETER (TOMS) ABSORBING AEROSOL PRODUCT , 2002 .

[5]  Ina Tegen,et al.  A comparison of seasonal and interannual variability of soil dust aerosols over the Atlantic Ocean as inferred by the TOMS AI and AVHRR AOT retrievals , 2001 .

[6]  Dale A. Gillette,et al.  A qualitative geophysical explanation for hot spot dust emitting source regions , 1999 .

[7]  V. Vallès,et al.  Geochemistry of saline soils in two arid zones of the Mediterranean basin. I. geochemistry of the chott melghir‐mehrouane watershed in Algeria , 1997 .

[8]  Robert G. Bryant,et al.  Application of AVHRR to monitoring a climatically sensitive playa. case study: Chott El Djerid, Southern Tunisia , 1999 .

[9]  Dr Robert Bryant.  Monitoring hydrological controls on dust emissions: preliminary observations from Etosha Pan, Namibia , 2003 .

[10]  J. Deluisi,et al.  Optical depth, size distribution and flux of dust from Owens Lake, California , 1999 .

[11]  Alexander Smirnov,et al.  Comparisons of the TOMS aerosol index with Sun‐photometer aerosol optical thickness: Results and applications , 1999 .

[12]  Paul Ginoux,et al.  A Long-Term Record of Aerosol Optical Depth from TOMS Observations and Comparison to AERONET Measurements , 2002 .

[13]  M. W. Buch,et al.  Mineralogy and geochemistry of the sediments of the Etosha Pan Region in northern Namibia: a reconstruction of the depositional environment☆ , 1996 .

[14]  M. Reheis.  Dust deposition downwind of Owens (dry) Lake, 1991-1994 : Preliminary findings , 1997 .

[15]  Robert G. Bryant,et al.  Marine-like potash evaporite formation on a continental playa: case study from Chott el Djerid, southern Tunisia , 1994 .