Biomass Burning Emissions of Black Carbon over the Maritime Continent and ENSO Variability

Journal Article · Wed Nov 22 00:00:00 EST 2023 · Journal of Climate

DOI:https://doi.org/10.1175/jcli-d-22-0553.1· OSTI ID:2246584

Xie, Biyin ^[1]; Yang, Yang  ^[1]; Wang, Hailong  ^[2]; Wang, Pinya ^[1]; Liao, Hong ^[1]

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1. Nanjing Univ. of Information Science and Technology (China)
2. Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)

Fire emissions from the Maritime Continent (MC) over the western tropical Pacific are strongly influenced by El Niño–Southern Oscillation (ENSO), posing various climate effects to the Earth system. Here, in this study, we show that the historical biomass burning emissions of black carbon (BC_bb) aerosol in the dry season from the MC are strengthened in El Niño years due to the dry conditions. The eastern Pacific type of El Niño exerts a stronger modulation in BC_bb emissions over the MC region than the central Pacific type of El Niño. Based on simulations using the fully coupled Community Earth System Model (CESM), the impacts of increased BC_bb emissions on ENSO variability and frequency are also investigated in this study. With BC_bb emissions from the MC scaled up by a factor of 10, which enables the identification of climate response from the internal variability, the increased BC_bb heats the local atmosphere and changes land–sea thermal contrast, which suppresses the westward transport of the eastern Pacific surface water. It leads to an increase in sea surface temperature in the eastern tropical Pacific, which further enhances ENSO variability and increases the frequency of extreme El Niño and La Niña events. This study highlights the potential role of BC_bb emissions on extreme ENSO frequency, and this role may be increasingly important in the warming future with higher wildfire risks.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Biological and Environmental Research (BER). Earth & Environmental Systems Science (EESS)
• Grant/Contract Number: AC05-76RL01830
• OSTI ID: 2246584
• Report Number(s): PNNL-SA-190255
• Journal Information: Journal of Climate, Vol. 36, Issue 24; ISSN 0894-8755
• Publisher: American Meteorological Society
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
Maritime Continent
Atmospheric circulation
ENSO
Climate models
Aerosol radiative effect
Biomass burning