AERONET Remotely Sensed Measurements and Retrievals of Biomass Burning Aerosol Optical Properties During the 2015 Indonesian Burning Season

Authors

T. F. Eck, NASA Goddard Space Flight CenterFollow
B. N. Holben, NASA Goddard Space Flight Center
D. M. Giles, NASA Goddard Space Flight Center
I. Slutsker, NASA Goddard Space Flight Center
A. Sinyuk, NASA Goddard Space Flight Center
J. S. Schafer, NASA Goddard Space Flight Center
A. Smirnov, NASA Goddard Space Flight Center
M. Sorokin, NASA Goddard Space Flight Center
J. S. Reid, Naval Research Lab
A. M. Sayer, NASA Goddard Space Flight Center
N. C. Hsu, NASA Goddard Space Flight Center
Y. R. Shi, NASA Goddard Space Flight Center
R. C. Levy, NASA Goddard Space Flight Center
A. Lyapustin, NASA Goddard Space Flight Center
Muhammad Arif Rahman, Agency for Meteorology Climatology and Geophysics
Soo-Chin Liew, National University of Singapore
Santo V. Salinas Cortijo, National University of Singapore
Tan Li, National University of Singapore
Daniel Kalbermatter, National University of Singapore
Kwoh Leong Keong, National University of Singapore
Muhammad Elifant Yuggotomo, BMKG Staklim Mempawah
Fanni Aditya, BMKG Staklim Mempawah
Maznorizan Mohamad, Malaysian Meteorological Department
Mastura Mahmud, Universiti Kebangsaan Malaysia
Tan Kok Chong, Stesen Meteorologi Kuching
Hwee-San Lim, Universiti Sains Malaysia
Yeap Eng Choon, Universiti Sains Malaysia
Gumilang Deranadyan, BMKG
Sheila D. A. Kusumaningtyas, The Indonesia Agency for Meteorology Climatology and Geophysics
Edvin Aldrian, Agency for Assessment and Application of Technology

ORCID IDs

T. F. Eck

D. M. Giles

A. Smirnov

J. S. Reid

A. M. Sayer

N. C. Hsu

Y. R. Shi

R. C. Levy

A. Lyapustin

Soo-Chin Liew

Santo V. Salinas Cortijo

Daniel Kalbermatter

Mastura Mahmud

Hwee‐San Lim

Sheila D. A. Kusumaningtyas

Date of this Version

2019

Citation

Journal of Geophysical Research: Atmospheres, 124, 4722–4740

Comments

© 2019. American Geophysical Union

Abstract

An extreme biomass burning event occurred in Indonesia from September through October 2015 due to severe drought conditions, partially caused by a major El Niño event, thereby allowing for significant burning of peatland that had been previously drained. This event had the highest sustained aerosol optical depths (AODs) ever monitored by the global Aerosol Robotic Network (AERONET). The newly developed AERONET Version 3 algorithms retain high AOD at the longer wavelengths when associated with high Ångström exponents (AEs), which thereby allowed for measurements of AOD at

675 nm as high as approximately 7, the upper limit of Sun photometry. Measured AEs at the highest monitored AOD levels were subsequently utilized to estimate instantaneous values of AOD at 550 nm in the range of 11 to 13, well beyond the upper measurement limit. Additionally, retrievals of complex refractive indices, size distributions, and single scattering albedos (SSAs) were obtained at much higher AOD levels than possible from almucantar scans due to the ability to perform retrievals at smaller solar zenith angles with new hybrid sky radiance scans. For retrievals made at the highest AOD levels the fine‐mode volume median radii were ~0.25–0.30 micron, which are very large particles for biomass burning. Very high SSA values (~0.975 from 440 to 1,020 nm) are consistent with the domination by smoldering combustion of peat burning. Estimates of the percentage peat contribution to total biomass burning aerosol based on retrieved SSA and laboratory measured peat SSA were ~80–85%, in excellent agreement with independent estimates.