Figure 4
From: High-resolution isotopic evidence for a potential Saharan provenance of Greenland glacial dust
Changes in the relative contributions of the Taklimakan, the Gobi and the Sahara to the Greenland dust deposition from the YD to the GS-5.1 together with paleoclimate proxy records. (a) The relative source strength (in fraction) of the three PSAs calculated using a mixing isotopic model (see Methods and Supplementary Table S2). Also shown are Greenland climatic events25. (b) The NGRIP Greenland ice core dust concentration record34. (c) Time intervals of Saharan aridity and humidity39,40,41,42 (see text). AHP indicates the African Humid Period. (d,e) Dust flux records from the northwest African margin site GC68 (19.36° N, 17.28° W)42 and the Mid-Atlantic site GGC3 (26.14° N, 44.80° W)41, respectively. (f,g) Lake Qinghai (36.32°–37.15° N, 99.36°–100.47° E), situated on the northeastern Tibetan Plateau, Westerlies climate index (WI, flux of >25 μm fraction) and Asian summer monsoon index (SMI)35, respectively. The non-dimensional Lake Qinghai SMI was quantified by normalizing and averaging two Asian summer monsoon (ASM) proxies (CaCO3 and total organic carbon flux) in the lake sediments, representing larger SMI values as the stronger ASM35.
