Fire–climate interactions through the aerosol radiative effect in a global chemistry–climate–vegetation model
<p>Fire emissions influence radiation, climate, and ecosystems through aerosol radiative effects. These can drive rapid atmospheric and land surface adjustments which feed back to affect fire emissions. However, the magnitude of such feedback remains unclear on the global scale. Here, we quant...
| Main Authors: | , , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2022-09-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://acp.copernicus.org/articles/22/12353/2022/acp-22-12353-2022.pdf |
| Summary: | <p>Fire emissions influence radiation, climate, and ecosystems through aerosol
radiative effects. These can drive rapid atmospheric and land surface
adjustments which feed back to affect fire emissions. However, the magnitude
of such feedback remains unclear on the global scale. Here, we quantify the
impacts of fire aerosols on radiative forcing and the fast atmospheric
response through direct, indirect, and albedo effects based on the two-way
simulations using a well-established chemistry–climate–vegetation model.
Globally, fire emissions cause a reduction of 0.565 <span class="inline-formula">±</span> 0.166 <span class="inline-formula">W m<sup>−2</sup></span>
in net radiation at the top of the atmosphere with dominant contributions by the
aerosol indirect effect (AIE). Consequently, terrestrial surface air
temperature decreases by 0.061 <span class="inline-formula">±</span> 0.165 <span class="inline-formula"><sup>∘</sup>C</span> with coolings of
<span class="inline-formula">>0.25</span> <span class="inline-formula"><sup>∘</sup>C</span> over the eastern Amazon, the western US, and boreal
Asia. Both the aerosol direct effect (ADE) and AIE contribute to such cooling,
while the aerosol albedo effect (AAE) exerts an offset warming, especially
at high latitudes. Land precipitation decreases by 0.180 <span class="inline-formula">±</span> 0.966 <span class="inline-formula">mm per month</span> (1.78 %<span class="inline-formula"> ±</span> 9.56 %) mainly due to the inhibition in central
Africa by AIE. Such a rainfall deficit further reduces regional leaf area
index (LAI) and lightning ignitions, leading to changes in fire emissions.
Globally, fire emissions reduce by 2 %–3 % because of the fire-induced
fast responses in humidity, lightning, and LAI. The fire aerosol radiative
effects may cause larger perturbations to climate systems with likely more
fires under global warming.</p> |
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| ISSN: | 1680-7316 1680-7324 |