Keywords: Subtropic ice sheet, collaps of summer monsoon, pacemaker of Ice Age, 14C-dating and Quaternary geology versus TCN

The High Glacial glaciation of High- and Central Asia has been reconstructed on the basis of glacigenic forms and petrographic- (sorting coefficient, C/N, lime content), grain size- and morphoscopic analyses. 5 new areas: Damodar-, Masherbrum-massif, Chapursan Valley, SE-Tibet between Tsangpo- and Yalong River and Dolpo have been investigated.

New data and data obtained since 1973 prove a 2800 m-thick icestream network and a Tibetan ice sheet of 2.4 mio. km². Data were gathered from the Zagros in the W to the Minya Konka and from the Himalaya to the Sajan in the N.

14C-datings classify this glaciation as Isotope Stage 3-2. From the maximum past glacier extension up to the current glacier margins, 14 glacier stages have been differentiated: 4 glacier stages of the Late Glacial-, 3 of the Neoglacial- and 6 of the Historical period. The number of glacier stages since the maximum glaciation agrees with that in several mountain-systems since the Last Glacial period. This is an indication of the Würmian age of the lowest ice margin positions.

Calibration of TCN-data: In the meantime the Quaternary-geological and glaciological (ELA-calculations) assessment of TCN-data and their control by 14C-datings on the S-margin of Tibet has shown that the TCN-datings carried out at a height of more than 4000 m are overestimated by a factor ~6.5, so that moraines, by mistake classified as belonging to the LGM, are of Neoglacial origin (Kuhle & Kuhle 2010).

Radiation balance measurements up to 6650 m indicate highest energies, making Tibet today's most important heating surface. At glacial times 70% of this energies were reflected by that High Asian-glacier area, i.e. 32% of the entire global cooling.
 

Kuhle, M., Kuhle, S., 2010, Review on Dating methods: Numerical Dating in the Quaternary Geology of High Asia. In: Journal of Mountain Science (2010) 7: 105-122.