Northern-high-latitude permafrost and terrestrial carbon response to two solar geoengineering scenarios
<p>The northern-high-latitude permafrost contains almost twice the carbon content of the atmosphere, and it is widely considered to be a non-linear and tipping element in the earth's climate system under global warming. Solar geoengineering is a means of mitigating temperature rise and re...
| Main Authors: | , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2023-01-01
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| Series: | Earth System Dynamics |
| Online Access: | https://esd.copernicus.org/articles/14/55/2023/esd-14-55-2023.pdf |
| Summary: | <p>The northern-high-latitude permafrost contains almost twice the carbon
content of the atmosphere, and it is widely considered to be a non-linear and
tipping element in the earth's climate system under global warming. Solar
geoengineering is a means of mitigating temperature rise and reduces some of
the associated climate impacts by increasing the planetary albedo; the
permafrost thaw is expected to be moderated under slower temperature rise.
We analyze the permafrost response as simulated by five fully coupled earth
system models (ESMs) and one offline land surface model under four future
scenarios; two solar geoengineering scenarios (G6solar and G6sulfur) based
on the high-emission scenario (ssp585) restore the global temperature from
the ssp585 levels to the moderate-mitigation scenario (ssp245) levels via
solar dimming and stratospheric aerosol injection. G6solar and G6sulfur can
slow the northern-high-latitude permafrost degradation but cannot restore
the permafrost states from ssp585 to those under ssp245. G6solar and
G6sulfur tend to produce a deeper active layer than ssp245 and expose more
thawed soil organic carbon (SOC) due to robust residual high-latitude
warming, especially over northern Eurasia. G6solar and G6sulfur preserve
more SOC of 4.6 <span class="inline-formula">±</span> 4.6 and 3.4 <span class="inline-formula">±</span> 4.8 Pg C (coupled ESM simulations) or
16.4 <span class="inline-formula">±</span> 4.7 and 12.3 <span class="inline-formula">±</span> 7.9 Pg C (offline land surface model
simulations), respectively, than ssp585 in the northern near-surface
permafrost region. The turnover times of SOC decline slower under G6solar
and G6sulfur than ssp585 but faster than ssp245. The permafrost
carbon–climate feedback is expected to be weaker under solar geoengineering.</p> |
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| ISSN: | 2190-4979 2190-4987 |