Replication data for: Hot spots in Riau, haze in Singapore: the June 2013 event analyzed. ASB Policybrief No. 33 uri icon


  • The fire-haze episode straddling the Strait of Malacca in June 2013 has reignited debates that have been repeated for at least the last two decades. All allegations of causation are probably true: somewhere. None of them seem to be true as generalizations that can be stated with confidence. In the current debate, finger pointing still alternates between the small- and large-scale agricultural operators. The latter include companies with headquarters in Singapore and Malaysia, where ironically, the undesirable haze accompanies the financial returns on their investments. We analyzed the spatial data and, in combination with reports from the field, a new perspective has emerged. Using a free data source from the Earth Observing System ( and Indonesia peat (Wahyunto, Ritung and Subagjo, 2003) and moratorium map , as well as our own 2010 land-cover classificat ion data (from the ALLREDDI project), we selected only the hotspots with a >90% confidence level recorded. Hot spots are the most widely used indicator of surface fires, but need on-the-ground verification as there can be other causes of high temperatures being reflected to the satellite sensors (Arino and Rosaz, 1999). The number of hotspots observed varies from year to year but the June 2013 event in Riau stands out from the pattern of the last 10 years. A total of 3270 fire hot spots on the island of Sumatra were detected for 2013, with over 90% in June and 2492 just for the week of 26 June; 78% (1942 hot spots) were found to be located on peatland and they likely the main cause of persisting haze. More than 95% of the hot spots in Sumatra occurred in Riau province. The two dominant trends of land-use change in the area are the development of plantation forestry for the pulp and paper industry and the expansion of oil-palm plantations. Both are implicated in the June 2013 fires, with hot spots occurring in oil-palm and pulp-and-paper parts of the landscape. According to a World Resources Institute report (Sizer et al 2013), 27% of the hotspots that occurred “20 June were inside timber plantations and 20% in oil-palm plantations. Mining concessions might be implicated as well but since details of the current concessions in Indonesia are not in the public domain further analysis is constrained

publication date

  • 2013