I wish it would rain

By Bryan Walker 28/11/2010

We (or at least some of us) rightly feel apprehension and alarm at the prospect of melting glacial and polar ice. There are new reminders that we should be equally alarmed at the prospect of Amazonian drought. Joe Romm has written a lengthy post on Climate Progress drawing attention to the 2010 drought which may prove more widespread and severe than the 2005 drought, itself identified as a 1-in-100-year type event.  He quotes an email to that effect from forest scientist and Amazon expert Simon Lewis (he of the Sunday Times fightback and subsequently granted apology).

Lewis recommends an article in the Global Post which is well worth reading.  It refers to three scientists. Oliver Phillips, a tropical ecology professor at the University of Leeds, speaks of his concern that parts of the Amazon may be approaching a threshold point beyond which the eco-system can’t go. He led a team of researchers who studied the damage caused by the 2005 drought which caused a massive die-off of trees and led to the forest expelling carbon dioxide rather than absorbing it. He’s worried that another severe drought is following so soon after the last one.  Greg Asner, an ecologist at the Carnegie Institution for Science, points out that some tropical forests in the world now are starting to be exposed to temperatures they’ve never experienced. His studies show that higher temperatures and shifts in rainfall could leave as much as 37 percent of the Amazon so radically altered that the plants and animals living there now would be forced to adapt, move or die. Foster Brown, an environmental scientist at the federal university in the Brazilian state of Acre, comments that drought has made ecosystems so dry that instead of a being a barrier to fire, the forest became kindling.

Nikolas Kozloff’s book No Rain in the Amazon which I reviewed earlier this year refers to much-cited scientist Philip Fearnside of Brazil’s National Institute for Research in the Amazon, who for some years has observed the connection between drought and El Niño-like conditions which are expected to become more frequent with continued global warming. He too is concerned that the Amazon might dry out and be placed in jeopardy as a result of climate change. Kozloff also reports the belief of some researchers that warming sea surface temperatures in the tropical North Atlantic Ocean are linked to Amazon drought.

In an October press release Brazil’s Amazon Environmental Research Institute (IPAM) comments:

“The drought of 2010 still hasn’t ended in the Amazon and could surpass that of 2005 as the region’s worst during the past four decades… Even if this doesn’t occur, the forest will have already experienced three extreme dry spells in just 12 years, two of which occurred during the past five years: 1998, 2005 and 2010. And this is not including the drought of 2007, which affected only the Southeastern Amazon and left 10 thousand sq. km. of forest scorched in the region…`The Amazon that had wet seasons so well-defined that you could set your calendar to them — that Amazon is gone,’ says ecologist Daniel Nepstad of IPAM…”

Deforestation of the Amazon by humans has long been a major international concern, and Simon Lewis’s communication with Jo Romm indicates that there is a degree of good news on that front in that since 2005 deforestation rates have been radically reduced. But the droughts are bad news. They kill trees and promote damaging fires, ’potentially leading to a drought-fire-carbon emissions feedback and widespread forest collapse’. Lewis expresses particular concern that while two unusual droughts clearly don’t make a trend, they are consistent with some model projections made well before 2005: ’that higher sea surface temperatures increase drought frequency and intensity, leading later this century to substantial Amazon forest die-back.’

Hot Topic commenter Tony on a previous post linked to an Al Jazeera video clip (which I’ve posted below), with the observation that if anything should motivate a sense of urgency in Cancun, what it portrayed should. Simon Lewis also linked what may be happening in the Amazon to the Cancun conference. Not with any great expectation, but with a dry reminder that the risks to which we are exposing humanity don’t diminish because we ignore them. ’While little is expected of the climate change talks in Cancun next week, the stakes, in terms of the fate of the Amazon are much higher than they were a year ago in Copenhagen.’

I hope it doesn’t appear as incidental if I note before concluding that the droughts affect not only the forest and through it the welfare of the whole planet but also the local populations whose livelihood and wellbeing is jeopardised. The Global Post article reports the anxiety of village chief Mariazinha Yawanawa. Her people are sustained by the forest. They hunt in the woods, fish the rivers and grow crops in the clearings where they live.  ’Everything has changed. We don’t know when we can plant. We plant and then the sun kills everything. If it continues like this, we expect a tragedy.’

[The Temptations]