The Last Stand of the Orangutan

FORESTS ON FIRE

Insular Southeast Asia endures months of smoke-filled air every year during the dry season. Farmers and plantation developers deliberately and illegally set fire to the forest to clear the way for crops, and in logged-over forest, fire spreads rapidly. When peat swamp forests catch alight, the peat burns as well as the trees. These fires can spread underground, and persist for long periods, destroying natural habitats and releasing substantial volumes of greenhouse gases.

The annual burning in Southeast Asia is usually worst in El Niño years, which are exceptionally dry. The worst recorded so far, in 1997–8, destroyed 95% of the forest in Kutai National Park: this protected area had previously been subject to high levels of log- ging, and may no longer be viable (Rautner et al. 2005). In 2006, fire levels peaked again in what is thought to be the start of an El Niño season that could continue through March 2007 (Figure 18; CPC/NCEP 2007).

Sumatra

Borneo

Figure 18: Fire and smoke over Borneo and Sumatra, late September to October 2006 (© Jesse Allen, Earth Observatory/MODIS Rapid Response team).

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