Abstract
Southeast Asia, in particular Indonesia, has periodically struggled with intense fire events. These events convert substantial amounts of carbon stored as peat to atmospheric carbon dioxide (CO2) and significantly affect atmospheric composition on a regional to global scale. During the recent 2015 El Niño event, peat fires led to strong enhancements of carbon monoxide (CO), an air pollutant and well-known tracer for biomass burning. These enhancements were clearly observed from space by the Infrared Atmospheric Sounding Interferometer (IASI) and the Measurements of Pollution in the Troposphere (MOPITT) instruments. We use these satellite observations to estimate CO fire emissions within an inverse modelling framework. We find that the derived CO emissions for each sub-region of Indonesia and Papua are substantially different from emission inventories, highlighting uncertainties in bottom-up estimates. CO fire emissions based on either MOPITT or IASI have a similar spatial pattern and evolution in time, and a 10% uncertainty based on a set of sensitivity tests we performed. Thus, CO satellite data have a high potential to complement existing operational fire emission estimates based on satellite observations of fire counts, fire radiative power and burned area, in better constraining fire occurrence and the associated conversion of peat carbon to atmospheric CO2. A total carbon release to the atmosphere of 0.35–0.60 Pg C can be estimated based on our results.This article is part of a discussion meeting issue ‘The impact of the 2015/2016 El Niño on the terrestrial tropical carbon cycle: patterns, mechanisms and implications'.
Highlights
Fires in Indonesia are ignited every year by agricultural activities and land clearing practices [1]
We show the consistency between the emissions derived from these two products and advocate the use of these observations in fire monitoring systems such as the Copernicus atmosphere monitoring service (CAMS) towards constraining fire emissions
To test the potential magnitude of the effect that changes in oxidized by atmospheric hydroxyl (OH) due to the Indonesian fires could have on estimated emissions [34], we performed two sensitivity tests, ‘Infrared Atmospheric Sounding Interferometer (IASI) OH’ and ‘IASI OH GFED,’ using modified OH fields
Summary
Fires in Indonesia are ignited every year by agricultural activities and land clearing practices [1]. Previous inverse modelling estimates of CO emissions from the 2015 Indonesian fires were made by Huijnen et al [15] and Yin et al [16], who estimated emissions of 84 (September and October 2015) and 122 Tg CO (entire year 2015), respectively Both studies used MOPITT data, which were shown to have a poorer performance at detecting extreme events compared to IASI [17]. To test the potential magnitude of the effect that changes in OH due to the Indonesian fires could have on estimated emissions [34], we performed two sensitivity tests, ‘IASI OH’ and ‘IASI OH GFED,’ using modified OH fields In these simulations, standard OH fields were scaled with the daily three-dimensional ratio between two global chemistry simulations with the Composition Integrated Forecasting System (C-IFS) model [15,35], with and without peat emissions of CO, NOx and NMVOC. Most simulations presented use GFAS v.1.3 [13] as prior biomass burning emissions, except for ‘IASI OH GFED’, which uses GFED4s [12] as prior
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
