High-Resolution Reconstruction of the South Asian Monsoon from the Puruogangri Ice Cores (Tibet)

Ohio State University Research Foundation -Do Not Use, Columbus OH

Investigators

Abstract

This research will yield the first climatic and environmental records ever recovered from the center of the Tibetan Plateau by analyzing two ice cores measuring 118.6 and 214 meters that were recovered from the Puruogangri ice cap during a joint United States-China expedition between September 10 and November 10, 2000 funded by the National Science Foundation. These unique ice cores join other archives of changes in climate on the Tibetan Plateau that document an unprecedented warming of the atmosphere in the 20th century. Preliminary analyses indicate that both cores contain visible dry-season dust layers and may allow annual dating back to ~80 BC and the reconstruction of a history of precipitation fluctuations that are likely to reflect variations in the intensity of the monsoon system that is affected by El Nino-Southern Oscillation (ENSO) events. These cores will be analyzed for stable isotopes of oxygen and deuterium and aerosol chemistry to aid in the reconstruction of the history of Asian aridity and provide a record of the past temperatures and atmospheric circulation patterns for the region. The ice of the Puruogangri contains information that is an essential component in linking long, high-resolution records from pole to pole to allow an assessment of the global nature of abrupt climate variations. This is important because the Tibetan Plateau and surrounding mountain ranges contain the largest volume of ice outside the Polar Regions. The meltwater from the climatically sensitive glaciers form the headwaters of such important rivers as the Indus, Yangtze, Huang (Yellow) and the Ganges.