Source: Xinhua
04-20-2009 11:43
Special Report: Tech Max
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| Droughts worse than the infamous Sahel drought are part of the normal climate regime for West Africa and global warming may intensify their recurrence, a new study says.(File photo) |
The study, published in the journal Science on Thursday, reported that for the first time, U.S. researchers have developed an almost year-by-year record of the last 3,000 years of West Africa's climate.
In that period, catastrophic droughts occurred every 30 to 65 years, and the pattern can be expected to continue in the future, the research team reported.
The research team determined the region's past climate by analyzing the annual layers of sediment deposited in Ghana's Lake Bosumtwi, geological records of the lake level, and other climate indicators.
"What's disconcerting about this record is that it suggests that the most recent drought was relatively minor in the context of the West African drought history," said Timothy Shanahan, a member of the team.
