Interannual variability in the Saharan dust source activation—Toward understanding the differences between 2007 and 2008

摘要: The activation of Saharan dust sources is characterized by a diurnal and seasonal cycle strong interannual variability. Here reasons for the still unclear changes were investigated using example 2007 2008, which years with clear difference in number observed source (DSA) events. A detailed analysis images derived from satellite observations showed that sudden increase DSA at turn year 2007/2008 spreads within some months eastern to northwestern parts North Africa. remains on this significantly enhanced level during whole 2008. An examination regional model global reanalysis results, data, was performed identify drivers different patterns, revealed many individual factors contributed This includes Sahel rainfall distribution, wind field over Africa, differences strength West African Heat Low, occurrence cold surges propagating Mediterranean into Sahara. determining factor least these influences appears be sea surface temperatures, especially tropical Indian Pacific Oceans, Sea, affecting large-scale local atmospheric circulation patterns finally fostering DSA. alluvial sediments as after heavy rainfalls also plays an important role. Its contribution part further research activity.