5.1 MOPITT data used to study pollution effects of 2015 El Niño fires in Indonesia

During September and October 2015, agricultural burning in Indonesia caused an air quality disaster. Burning during this time of year is not uncommon, but the large 2015 El Niño resulted in extremely low precipitation in both Sumatra and Kalimantan (Borneo). As reported in Field et al., (2016), measurements of pollution from satellite observations, including carbon monoxide (CO) from MOPITT, all show large increases when precipitation is lower than 4 mm/day. Since fires in Indonesia are mostly set for clearing land or fertilization, this study recommends limiting agricultural burning for low precipitation forecasts. In addition, many of the fires in Indonesia are used to clear peat swamp forests that are drained for farming, which have much higher stored carbon than other forests. This carbon is released to the atmosphere when the peat is burned. Using MOPITT data, Jiang et al., (2016) estimated that the Indonesian fires in October, 2015 emitted 92 Tg of CO, which is about 3 times higher than the 2006 El Niño driven fires.

Sample template image
Figure 1. Top panel shows the time series of multivariate ENSO (El Niño/Southern Oscillation) index from NOAA, with the largest recent El Niño events in 1997 and 2015 highlighted. Bottom left panel shows the average rainfall for September 2015 over Indonesia from the NASA Global Precipitation  Measurement (GPM). Bottom right panel shows MOPITT CO near the surface averaged for September 2015, where non-polluted levels are typically around 100 ppbv. (Rainfall and CO images from earthobservatory.nasa.gov)

References:

Field, R. et al., 2015 Indonesian fire activity and smoke pollution show persistent non-linear sensitivity to El Niño-induced drought, PNAS, 2016, 9204–9209, doi: 10.1073/pnas.1524888113

Jiang, Z., Worden, J. R., Worden, H., Deeter, M., Jones, D. B. A., Arellano, A. F., and Henze, D. K.: A fifteen year record of CO emissions constrained by MOPITT CO observations, Atmos. Chem. Phys. Discuss., doi:10.5194/acp-2016-811, in review, 2016.