Sumatra's forests are on fire again, less than a year after blazes burned large areas and covered Singapore and parts of Malaysia in thick smoke.
While the fires in Indonesia might seem far away for many people, they are everyone's problem. Many of the blazes are on deep peat lands, producing huge plumes of smoke and large amounts of carbon dioxide and other greenhouse gases that are stoking climate change. This year's fires are just as intense and threaten a far worse fire emergency because of unusually dry weather that is set to continue for some months. Worse still, there are increasing signs of an El Nino weather pattern for later this year.
El Nino events usually bring drier weather to Indonesia and a spike in forest fires, with the intense 1997-98 El Nino triggering some of the worst fires in living memory in Indonesia.
The Washington-based World Resources Institute, using fire hotspot data from NASA, says 3,101 "high-confidence" fire alerts were calculated between February 20 and March 11 on Sumatra. That exceeds the 2,643 high-confidence fire alerts detected from June 13 - June 30, at the peak of the previous fires and haze crisis, WRI says.
Extreme drought in the region has fuelled the fires and monsoon winds are blowing the acrid smoke back across Sumatra island instead of Malaysia and Singapore, explaining why the latest fire crisis hasn't received as much publicity as last year. That will change if the fires persist and the winds change direction.
The fires undermine Indonesia's international pledge to reduce greenhouse gas emissions by 2020 because of the large amount of carbon dioxide they produce.
Just as disturbing are the huge health costs.
Nearly 50,000 people in Sumatra were suffering from respiratory illness from the worsening smoke, or haze, a spokesman for Indonesia's National Disaster Management Agency was quoted as saying this week, with pollution reaching extremely hazardous levels in several districts of Riau province opposite Singapore and Malaysia.
Fires are an annual problem in Indonesia, many triggered by farmers trying to clear the land for agriculture or to stake a claim to land. Some companies use fire to prepare the land for plantations. The fires, though illegal, normally occur mid-year but unusually dry weather has made conditions ripe for wildfires.
Drained peat, which is rich in carbon, can burn for weeks or months, producing a thick smoke. Last year, intense fires lasted for weeks and pollution readings in Singapore reached record levels in June, prompting the government to vow stern action against Singapore-based palm oil and pulp and paper firms proven to have caused some of the fires.
Just how much greenhouse gas pollution are we talking about?
A 2013 study by Indonesia's National Council on Climate Change estimated peat fires produced 183 million tonnes of carbon dioxide-equivalent (CO2-e) in Sumatra in 2013 and 54.9 Mt CO2-e in Kalimantan, Indonesia's part of Borneo island. That's roughly 4.5 times New York City's annual emissions of 54 million tonnes based on 2010 levels.
In extreme drought years, such as 1997-98, fires can cover large areas of Indonesia and produce immense amounts of greenhouse gas pollution, highlighting the need for better law enforcement and fire-fighting capacity.
During 1997-98, an estimated 2 million hectares (4.9 million acres) of forest and 5 million hectares (12.4 million acres) of non-forested areas burned, with smoke affecting 75 million people across large parts of Southeast Asia, according to the National Council on Climate Change. Carbon emissions from the fires have been estimated at between 15 and 40 percent of annual global fossil fuel pollution.
The present fires in Sumatra challenge the government's ability to put them out and to crack-down on those who start them. They also challenge the government's commitment to reduce the nation's carbon emissions by 26 percent, or 700 Mt CO2-e, by 2020 from business-as-usual levels and to slash the number of fires, or hotspots, 20 percent a year until 2020. Both those targets seem unlikely to be met, particularly to people living in the fire-prone Sumatra provinces of Riau and Jambi and nearby Singapore, where the smell of peat smoke hangs heavily in the air again and gives everything a dirty, brownish hue.