Two distinct seasonal Asian source regions for mineral dust deposited in Greenland (NorthGRIP)

A four-year, high-resolution (<2 mo) record of mineralogical and isotopic (Sr and Nd) characteristics of mineral dust deposited at NorthGRIP confirms the seasonal variability in the eastern Asian source regions providing dust to northern Greenland at present. Comparison of the Sr and Nd isotopic compositions of the dust with those of potential source area samples from China and Mongolia support that the Takla Makan desert is the primary source, supplying most if not all of the mineral particles during the dusty spring season. A different source area, however, plays a role during most of year and during the low-dust season ( summer through winter) in particular. Inner Mongolian deserts of northern China, including the Tengger and the Mu Us, are likely candidates but the Mongolian Gobi is ruled out as a significant contributor to Greenland.