|Title||An analysis of aeolian dust in climate models|
|Publication Type||Journal Article|
|Year of Publication||2014|
|Authors||Evan AT, Flamant C., Fiedler S., Doherty O.|
|Journal||Geophysical Research Letters|
|Type of Article||Article|
|Keywords||aerosol; african dust; CMIP5; dust; emission; ocean; product; sahel; transport; tropical atlantic; validation; variability|
Aeolian dust is a key aspect of the climate system. Dust can modify the Earth's energy budget, provide long-range transport of nutrients, and influence land surface processes via erosion. Consequently, effective modeling of the climate system, particularly at regional scales, requires a reasonably accurate representation of dust emission, transport, and deposition. Here we evaluate African dust in 23 state-of-the-art global climate models used in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. We find that all models fail to reproduce basic aspects of dust emission and transport over the second half of the twentieth century. The models systematically underestimate dust emission, transport, and optical depth, and year-to-year changes in these properties bear little resemblance to observations. These findings cast doubt on the ability of these models to simulate the regional climate and the response of African dust to future climate change.
"Based on the results presented here CMIP5 models are unable to capture any of the salient features of northern African dust emission and transport. The exact nature of the biases are not elucidated here but are likely to be related to a variety of sources, including the dust size distributions and atmospheric and surface processes. We conclude that there is no reason to assume that the projections of dust emission and concentration for the 21st century have any validity."