Spatial Variation of Ionic and Isotopic Records From Snow Pits and Shallow Ice Cores in Central and Southeast Asia
Abstract
The alpine glaciated regions of the Belukha massif on the Altai, the massif of Pobeda-Khan Tengry in central Tien Shan, and the Bomi massif in Southeast Tibet were studied during annual summer field sessions since 1998. Analysis of soluble ion concentrations and äO18 signals in snow pits and shallow ice cores from glacier accumulation areas occurred to provide spatial coverage of documenting the climate change for the vast Asian continent, to identify the physical links controlling the glacio-chemical climate signals and to determine the appropriative deep ice core drilling sites. The geochemical records from central Asian sites show elevated levels of major ions corresponding to their terrestrial origin, continental location and greater influx of both primary and secondary aerosols compared to the Southeast Asia. Seasonal variability in the ice core obtained from the three glacier massifs was detected in the soluble ion concentrations of the vertical profiles throughout the firn pits and shallow ice cores to depths of 20 m. representing the time series for the past five years. äO18 analysis from the Asian sites shows pronounced peaks and are interpreted to represent annual accumulation layers. The signal variation is well-preserved at all locations and associates with seasonal changes in precipitation, air temperatures and sources of moisture. Analysis of the ä18O signals from the 14 m core obtained at southeast Tibet shows the considerable variability with the range of 14.19%, and mean value of -16.19%. These isotope and geochemistry records will aid in understanding inter-hemispheric dynamics and global teleconnection of climate, and can provide information important to the forecasting of global climate change linking regional responses with broad atmospheric circulation patterns from the North Atlantic to Pacific and Indian Oceans. In addition, these snow/firn records can be directly associated with the internal circulation system in Central Asia. The developed research proved the feasibility and benefit of a deep ice coring from the Altai glaciers. Since that, the 175 m. deep core was obtained in the Belukha Plateau during the summer of 2003 to expand the high-resolution climatic records in Central Asia.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2003
- Bibcode:
- 2003AGUFM.C12A0875J
- Keywords:
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- 1827 Glaciology (1863)