FIRE AND EL NINO IN BORNEO, SE ASIA 
Athanassios ZOUMAS', Martin WOOSTER?, George PERRY” 
PhD student athanassios.zoumas@kel.ac.uk, Reader martin.wooster@kel.ac.uk, *Lecturer 
george.perry@kcl.ac.uk 
Department of Geography, King's College London, Strand, London, WC2R 2LS, UK, Web: 
http://www.kcl.ac.uk/geography 
  
  
  
KEY WORDS: Remote Sensing, Forest Fire, Infrared, Temporal, Comparison, Correlation, AVHRR GAC, El 
Nifio 
ABSTRACT: 
This project investigates the relationship between fire activity and El-Nino-Southern Oscillation (ENSO) events in 
South East Asia using Borneo, Indonesia as a case-study. Low spatial resolution NOAA AVHRR GAC satellite 
data were used to investigate the occurrence of active fires during the El-Nifio episodes of the last 20 years. 
Results showed that the adjusted GAC fire count numbers were very well related to the LAC fire counts of the 
coincident imagery, indicating the efficacy of GAC data for providing quantitative fire information during El Nifio 
periods and specifically the1997-98 event on Borneo. 
The distribution of fires in time was analysed and compared to the strength of the El Niño-Southern Oscillation 
(ENSO) as measured by the sea surface temperature anomaly (SSTA) in the Niño 3 region of the Pacific Ocean. 
The strongest ENSO-fire association was observed when the total 16-months sum of ENSO index (Niño 3 
anomaly), from January of Year 0 to April of Year 1, compared against the total fire activity of the same time 
period. These first sixteen months of each 24-month fire event included the majority of the entire fire activity 
detected, representing the 80.61 per cent of the total 10-years fire activity in Borneo. Therefore, if this ENSO-fire 
relation remain consistent in future El -Nifio events, it could be possible to predict in advance the all-Borneo fire 
activity based on predictions of Nifio 3 anomaly. 
Orbiting Environmental Satellites (POES) (Kidwell, 
Introduction 1998). 
Previous studies have shown a close relationship The rationale in terms of fire detection was to use 
among fire activity and ENSO in various parts of the lowest possible fire detection threshold in order 
the world (Simard et al, 1985; Swetnam and to reduce errors of omission and to minimise the 
Betancourt, 1990; Kitzberger, 2002). In Indonesia along scan averaging effect of the GAC data 
burning occurs annually but a number of unusually production. Therefore, fire detection and false 
large fire events have occurred in recent times. detection identification were performed using a 
Several studies have documented the increased fire multispectral approach, rather than by applying a 
activity occurred in Indonesia during El Niño years, single threshold value (Kaufman ef a/., 1990). 
particularly the devastating fire activity of the Thresholds were reduced progressively until 
extreme 1982-83 and 1997-98 ENSO periods, contamination of resultant fire counts by the broad 
(Malingreau ef aL, 1985; Legg and Laumonier, background environment became visually apparent. 
1999: Wooster and Strub, 2002). The aim of this Threshold values were defined first by examining 
project is to investigate the relationship between fire the histograms of AVHRR channel 3, 4, 5 and 
activity and El-Nino-Southern Oscillation (ENSO) channel 3 minus channel 4 (T3-T4) and second by 
events in South East Asia during the 1982-1998 calculating basics statistics of minimum, maximum, 
period using Borneo, as a case-study. mean, variance and standard deviation values for 
fire affected pixels and main background features 
such as cloud free vegetated land, clouds, mainland 
Methods and Results waterbodies and sea. 
NOAA AVHRR Global Area Coverage (GAC) The developed pixel-by-pixel multi-channel fixed 
satellite data were used to investigate the occurrence threshold method was applied to the AVHRR data. 
of active fires during the El-Nino episodes of the According to this method a series of criteria must be 
last 20 years. Early nighttime GAC images that fulfilled by a pixel in order to be classified as a fire. 
included the entire case study region of Borneo for These criteria have the following form: 
the five study periods over ten years were 
downloaded from the Satellite Active Archive Test (1) T;>305°K to detect 
(SAA). Although GAC data are available since July features with high channel 3 brightness 
of 1981, LAC data occur only sporadically in this 
archive and not for all of the years. This is mainly temperature i.e. likely (potential) fires 
due to storage limitations on board the NOAA Polar Test(2) T4-T,» 6°K to avoid 
warm surfaces without fires 
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