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A man in the dry bottom of the Black River, tributaries of the Amazon. "Levels of Amazonian vegetation greenness, a measure of health- decreased dramatically in an area of \u200b\u200bover three and a half times the size of Texas and did not recover to normal levels even after the drought ended in late October 2010, "said Liang Xu, lead author of the study at the University of Boston.
The future of the Amazon forest
sensitivity to drought in the Amazon Rainforest is a topic of intense study. Scientists are concerned because the computer models predict that in a changing climate, with temperatures warm and altered rainfall patterns, the resulting moisture stress may cause some forest were replaced by grasslands or savanna woody . This would make the carbon stored in decaying wood are released into the atmosphere, which could accelerate global warming.
The Intergovernmental Panel on United Nations on Climate Change (IPCC) has warned that droughts similar may be more common in the Amazon region in the future.
The full study has been prepared by an international team of scientists who have studied for more than a decade of satellite data MODIS and NASA's TRMM.
The analysis of these data has enabled detailed mapping showing the decrease in green vegetation by drought in 2010. The study has been accepted for publication in the journal Geophysical Research Letters, a journal of the American Geophysical Union. Consequences
driest year
Authors first developed maps of the areas affected by drought thresholds of below average rainfall. The maps show that the drought of 2010 green reduced by approximately 1.5 million square kilometers of vegetation in the Amazon, more than four times the area affected by the recent severe drought in 2005.
"Data from MODIS satellite spectrometer on green vegetation suggest a broader impact, severe and long lasting in the Amazonian vegetation of what can be deduced based solely on rainfall data," said Arindam Samanta, coauthor and researcher Atnopsheric and Environmental Research.
The severity of the drought of 2010 also was noted in the records of water levels in rivers in the Amazon basin. Water levels began to fall in August 2010, reaching unprecedented levels in late October. The water levels began to increase only with the arrival of rains after winter.
" Last year was the driest year on the basis of data 109 years in the Black River, off the port of Manaus. In comparison, the lowest level during the drought of 2005 was only octave lower, "said Mark Costa, co-author of the Federal University of Viçosa, Brazil.
IRIN 
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