Consequences of DESERTification for the radiaTive Impact of atmospheric dust over the Middle East (DESERT-TIME)
Final Report Abstract
A destructive form of manmade desertification is the shrinkage of former lakes, leaving behind deserts which are sources of airborne dust, hazards for regional air quality. The causes of such environmental disasters are often due to water mismanagement, although climate change may also play a role. A severe example is the Aral Sea in Central Asia, a lake which used to be the size of Bavaria but which has lost ~90% of its area in the last sixty years, due to the diversion of its rivers for agriculture: it is now a desert known as the Aralkum. Using a computer model of atmospheric dust transport for a particular year, taking into account the changes in lake area we estimate that dust emissions from the Aralkum have doubled between the late 20th century and the early 21st century, posing hazards for people living in settlements to the east of the Aralkum, even to people in major cities over 800 km away. However from year to year the wind directions over the Aralkum vary, such that settlements in other areas of Central Asia will also be vulnerable to Aralkum dust. A puzzle for our understanding of dust in this area is that much of the dust storm activity is simulated to occur when the sky is cloudy, under which conditions Earth-observing satellites are unable to measure the presence or effects of dust. Still, the model makes it possible to infer the potential consequences of Aralkum dust for the radiative cooling and heating of the atmosphere and the surface. On average dust radiatively cools both the atmosphere and the surface in the local area of the Aralkum, however during individual events dust can also be strongly warming. These cooling and warming effects have consequences for the atmosphere, affecting the pressure systems over Central Asia and thereby altering the regional weather patterns.
Publications
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Dataset associated with Banks et al. (2022): Impacts of the desiccation of the Aral Sea on the Central Asian dust life-cycle
Banks, Jamie R.; Heinold, Bernd & Schepanski, Kerstin
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Impacts of the Desiccation of the Aral Sea on the Central Asian Dust Life‐Cycle. Journal of Geophysical Research: Atmospheres, 127(21).
Banks, Jamie R.; Heinold, Bernd & Schepanski, Kerstin
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Radiative cooling and atmospheric perturbation effects of dust aerosol from the Aralkum Desert in Central Asia.
Banks, Jamie R.; Heinold, Bernd & Schepanski, Kerstin
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Dataset associated with Banks et al. (2023): “Radiative cooling and atmospheric perturbation effects of dust aerosol from the Aralkum Desert in Central Asia”
Banks, Jamie R.; Heinold, Bernd & Schepanski, Kerstin
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Python code associated with Banks et al. (2023): “Radiative cooling and atmospheric perturbation effects of dust aerosol from the Aralkum Desert in Central Asia”
Banks, Jamie R.; Heinold, Bernd & Schepanski, Kerstin
