Ephemeral Lakes and Dust Emissions

Atmospheric mineral aerosols impact global climate through the absorption and scattering of incoming solar radiation and outgoing planetary radiation, as well as affecting ocean and terrestrial biogeochemistry. Due to the prevalence of arid surfaces with reduced vegetation cover and high velocity winds, much of the observed atmospheric dust is derived from susceptible surfaces within dryland regions.

Work has shown that topographic lows are the predominant sources of atmospheric desert dust within drylands. However, there are no general theories of why some basins are more active dust sources than other regions. Gross changes in the hydrology of an ephemeral lake system can lead to extreme changes in regional dust emissions (eg Owens Lake). It is possible, therefore, that changes in the frequency and extent of natural inundation occurring on large ephemeral lake systems may lead to significant fluctuations in regional dust loadings on a seasonal and inter-annual basis.

Research here focuses on using a range of remote sensing approaches (eg TOMS, POLDER, AVHRR) to constrain the affect of inundation on dust emissions from ephemeral lake systems in Africa.

Including Collaboration with: Natalie Mahowold (UCSB/NCAR), Giles Wiggs (Oxford), Frank Eckhardt (UCT) and Richard Washington (Oxford). Funding from NERC and the Royal Society.