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Amazon river at record low levels; deforestation blamed mongabay.com September 30, 2005 
The Amazon River in Peru is at its lowest level in 30 years of record keeping according to a report in Peruvian daily newspaper El Comercio. Local officials say deforestation is the likely culprit of the low water levels. Local officials are blaming deforestation of the upper reaches of the Amazon in the Andes for the fall in river levels. Forest clearing impacts rainfall by disrupting the local water cycle. Under normal conditions, forests add to local humidity through transpiration -- the process by which plants release water through their leaves. Moisture is transpired and evaporated into the atmosphere where it contributes to the formation of rain clouds. Scientists estimate that 50-80% of the moisture in the central and western Amazon remains in the ecosystem water cycle. However, when forests are cut, as is the case in Peru, less moisture is evapotranspired into the atmosphere, resulting in the formation of fewer rainclouds and less rainfall. Officials fear that low water problems will only worsen in coming years as more forest is cleared and glaciers in the Andes continue to retreat. Glaciers, which are the source for as much as 50% of the water in the upper Amazon, are fast disappearing in Peru. According to a 1997 study by the Peruvian government, the country's glaciers have shrunk by more than 20% in the past 30 years. Further, the National Commission on Climate Change in Lima projects that Peru will lose all its glaciers below 18,000 feet in elevation in the next decade and possibly all its glaciers within the next 40 years. The impact on the Amazon, when combined with deforestation, could be devestating to the region's climate, water cycle and economy. October 1 update from The Guardian The following is excerpted from "Amazon dries out as worst ever drought hits rainforest" by Alex Bellos in Manaus, Saturday October 1, 2005
"There is no rain here because the air is descending, which prevents the formation of clouds," said Ricardo Dellarosa, of the Amazon Protection Organisation (Sipam) in Manaus. "The air is descending here because the air is rising very intensely in the north Atlantic, creating storms and hurricanes. What goes up must come down." Gilvan Sampaio of the National Institute of Space Research said the north Atlantic was slightly warmer than usual, which had shifted the tropical weather system further north. A secondary factor, he added, was that cold fronts that usually came from the south of Brazil at this time of year had not been arriving. "These cold fronts have been heading straight into the ocean, instead of heading north towards the Amazon." Even though the river levels in the south-western Brazilian Amazon are always low at this time of year, the scale is much worse than usual and has hit areas never previously affected. "It's the worst it's been in 60 years," said Elpidio Gomes da Silva Filho, head of the Administration of West Amazon Waterways. BACKGROUND The Amazon River The Amazon River is the most voluminous river on Earth, eleven times the volume of the Mississippi, and drains an area equivalent in size to the United States. During the high water season, the river's mouth may be 300 miles wide and up to 500 billion cubic feet per day (5,787,037 cubic feet/sec) flow into the Atlantic. For reference, the Amazon's daily freshwater discharge into the Atlantic is enough to supply New York City's freshwater needs for nine years. The force of the current, from sheer water volume alone and virtually no gradient, causes the current to continue flowing 125 miles out to sea before mixing with Atlantic salt water. The Amazon is also one of the most biodiverse regions on the planet, housing up to 30% of the world's species. The Amazon river alone is home to some 3000 species of fish. The History of the Amazon
About ten million years ago, waters worked through the sandstone to the west and the Amazon began to flow eastward. At this time the Amazon rainforest was born. During the Ice Age, sea levels dropped and the great Amazon lake rapidly drained and became a river. Three million years later, the ocean level receded enough to expose the Central American isthmus and allow mass migration of mammal species between the Americas. This article used information from El Comercio via the LatinReporters.com web site. News index | RSS | Add to MyYahoo! Advertisements: Organic Apparel from Patagonia | Insect-repelling clothing |
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