American Geophysical Union | 12 July 2010
Storm Killed Half Billion Trees in Amazon RainforestA single, huge, violent storm that swept across the whole Amazon forest in 2005 killed half a billion trees, a new study shows
While storms have long been recognized as a cause of Amazon tree loss, this study is the first to produce an actual body count. And, the losses are much greater than previously suspected, the study's authors say. This suggests that storms may play a larger role in the dynamics of Amazon forests than previously recognized, they add.
Previous research had attributed a peak in tree mortality in 2005 solely to a severe drought that affected parts of the forest. The new study says that a single squall line (a long line of severe thunderstorms, the kind associated with lightening and heavy rainfall) had an important role in the tree demise. This type of storm might become more frequent in the future in the Amazon due to climate change, killing a higher number of trees and releasing more carbon to the atmosphere.
Tropical thunderstorms have long been suspected to wreak havoc in the Amazon, but this is the first time researchers have calculated how many trees a single thunderstorm can kill, says Jeffrey Chambers, a forest ecologist at Tulane University, in New Orleans, and one of the authors of the paper, which has been accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union (AGU).
Tulane University | 13 July 2010
Study Finds Amazon Storm Killed Half a Billion Trees
NASA JPL | 2010-232 | 13 July 2010
Widespread Amazon forest tree mortality from a single cross-basin squall line event
- Geophysical Research Letters (in press) DOI: 10.1029/2010GL043733
Discover Blogs | 80beats | 13 July 2010
North Americans may remember 2005 as the year of Hurricane Katrina, but below the equator another fearsome tempest wrought its own devastation that year. From January 16th to 18th a line of thunderstorms tore through the Amazon basin, and researchers who conducted a botanical “body count” after the storm estimate that it laid low between 441 and 663 million trees. ... [Time](Credit: Jeffrey Chambers)
Jeffrey Chambers, a forest ecologist at Tulane University, wanted to assess the damage caused throughout the massive Amazon basin, so he turned to satellites. ... [ScienceNOW]
Previously, other researchers had suggested that drought was responsible for a massive tree die-off in 2005, but Chambers says the satellite data and investigations of five field sites disproved the drought theory. In the hardest hit areas, the researchers found up to 80 percent of the trees snapped in half or blown over from their roots. ... [Discovery News]
Environmentalists note that the huge blow-down didn’t do the planet any favors, since the Amazon acts as a carbon sink–its living trees suck up and store planet-warming carbon dioxide. But as fallen trees rot, they release their stored carbon dioxide back into the atmosphere. What’s more, some climate change forecasts predict that there will be more severe storms in a warmer world, so it’s possible that the Amazon will be battered by more mega-storms in the future.
