Screening the ESA ATSR-2 World Fire Atlas (1997–2002)

[摘要] We screened the algorithm 2 (308 K threshold) European Space Agency (ESA)World Fire Atlas (WFA), for the period 1997–2002, using ancillary landcover, night-lights and volcanic activity datasets, combined withstatistical techniques to detect the occurrence of space-time clusters ofanomalous observations. The WFA is built using night time data from theAlong Track Scanning Radiometer (ATSR) onboard the Second EuropeanRemote-Sensing Satellite (ERS-2). The spatial resolution of the data is 1 kmand the satellite revisiting period is 3 days at the equator. The WFA is thefirst and longest archive of global fire observations and has been used innumerous biomass burning studies. Known limitations of the WFA are theinclusion of warm surfaces, gas flares, and city lights, and anunderestimation of actual global fire activity, due to the time of satelliteoverpass. Nevertheless, it has been considered that the WFA contains arelatively small proportion of observations that do not correspond tovegetation fires, which is not corroborated by our findings. During thestudy period, the annual percentage of false alarms and non-vegetation firesvaried from a minimum value of 20.6% in 1997 to a maximum of 27.9% in1998. Gas flares and hot bare soils are the major sources of false alarmsand non-vegetation fires.

[学科分类] 大气科学