for National Geographic News
An abrupt change in weather 700 years ago may have forced people on the Tibetan plateau to abandon their farms and reorganize their society, an anthropologist says.
Mark Aldenderfer of the University of Arizona is leading a research project in far western Tibet to piece together how the Asian monsoon—a system of summer winds that brings heavy rain—shifted and how the culture adapted.
His project's preliminary findings suggest that an abrupt shift in the monsoon caused famine, population movements, and political reorganization.
The research project started last year and will continue with at least two more field seasons.
The results of the research could hold lessons for modern societies faced with the likelihood of a changing climate, Aldenderfer added.
"Can we learn anything from what they did at 1300 A.D. that would help us understand how people are going to have to deal with any kinds of similar sorts of changes that might take place in the Asian monsoon during the process of global warming?" he asked.
Scientists credit the Asian monsoon with bringing much-needed summer rains to nearly half the world's population.
The seasonal shift in wind usually brings moisture-laden clouds to India, Bangladesh, China, and other countries in southeast Asia (see map of Asia).
Carrie Morrill at the National Climatic Data Center in Boulder, Colorado, has led research into past changes in the monsoon in southeastern Asia. Her team's findings suggest an abrupt shift in the monsoon around A.D. 1300.
"The shift had an interesting spatial pattern: It got drier in some areas, and it got wetter in other areas," Morrill said.
The shift over far western Tibet was probably to a drier phase, she added (see a printable map of the Tibetan plateau).
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