Reduced-complexity model for the impact of anthropogenic CO<sub>2</sub> emissions on future glacial cycles
<p>We propose a reduced-complexity process-based model for the long-term evolution of the global ice volume, atmospheric CO<span class="inline-formula"><sub>2</sub></span> concentration, and global mean temperature. The model's only external forcings are...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2021-11-01
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| Series: | Earth System Dynamics |
| Online Access: | https://esd.copernicus.org/articles/12/1275/2021/esd-12-1275-2021.pdf |
| _version_ | 1818987372161794048 |
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| author | S. Talento A. Ganopolski |
| author_facet | S. Talento A. Ganopolski |
| author_sort | S. Talento |
| collection | DOAJ |
| description | <p>We propose a reduced-complexity process-based model for
the long-term evolution of the global ice volume, atmospheric CO<span class="inline-formula"><sub>2</sub></span>
concentration, and global mean temperature. The model's only external forcings
are the orbital forcing and anthropogenic CO<span class="inline-formula"><sub>2</sub></span> cumulative emissions. The
model consists of a system of three coupled non-linear differential
equations representing physical mechanisms relevant for the evolution of
the climate–ice sheet–carbon cycle system on timescales longer than
thousands of years. Model parameters are calibrated using paleoclimate
reconstructions and the results of two Earth system models of intermediate
complexity. For a range of parameters values, the model is successful in
reproducing the glacial–interglacial cycles of the last 800 kyr, with the
best correlation between modelled and global paleo-ice volume of 0.86. Using
different model realisations, we produce an assessment of possible
trajectories for the next 1 million years under natural and several
fossil-fuel CO<span class="inline-formula"><sub>2</sub></span> release scenarios. In the natural scenario, the model
assigns high probability of occurrence of long interglacials in the periods
between the present and 120 kyr after present and between 400 and 500 kyr
after present. The next glacial inception is most likely to occur
<span class="inline-formula">∼50</span> kyr after present with full glacial conditions developing
<span class="inline-formula">∼90</span> kyr after present. The model shows that even already
achieved cumulative CO<span class="inline-formula"><sub>2</sub></span> anthropogenic emissions (500 Pg C) are capable
of affecting the climate evolution for up to half a million years, indicating
that the beginning of the next glaciation is highly unlikely in the next 120 kyr. High cumulative anthropogenic CO<span class="inline-formula"><sub>2</sub></span> emissions (3000 Pg C or higher),
which could potentially be achieved in the next 2 to 3 centuries if
humanity does not curb the usage of fossil fuels, will most likely provoke
Northern Hemisphere landmass ice-free conditions throughout the next half
a million years, postponing the natural occurrence of the next glacial
inception to 600 kyr after present or later.</p> |
| first_indexed | 2024-12-20T19:05:38Z |
| format | Article |
| id | doaj.art-4001f09c820144598aaa5330888a4b3c |
| institution | Directory Open Access Journal |
| issn | 2190-4979 2190-4987 |
| language | English |
| last_indexed | 2024-12-20T19:05:38Z |
| publishDate | 2021-11-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Earth System Dynamics |
| spelling | doaj.art-4001f09c820144598aaa5330888a4b3c2022-12-21T19:29:17ZengCopernicus PublicationsEarth System Dynamics2190-49792190-49872021-11-01121275129310.5194/esd-12-1275-2021Reduced-complexity model for the impact of anthropogenic CO<sub>2</sub> emissions on future glacial cyclesS. TalentoA. Ganopolski<p>We propose a reduced-complexity process-based model for the long-term evolution of the global ice volume, atmospheric CO<span class="inline-formula"><sub>2</sub></span> concentration, and global mean temperature. The model's only external forcings are the orbital forcing and anthropogenic CO<span class="inline-formula"><sub>2</sub></span> cumulative emissions. The model consists of a system of three coupled non-linear differential equations representing physical mechanisms relevant for the evolution of the climate–ice sheet–carbon cycle system on timescales longer than thousands of years. Model parameters are calibrated using paleoclimate reconstructions and the results of two Earth system models of intermediate complexity. For a range of parameters values, the model is successful in reproducing the glacial–interglacial cycles of the last 800 kyr, with the best correlation between modelled and global paleo-ice volume of 0.86. Using different model realisations, we produce an assessment of possible trajectories for the next 1 million years under natural and several fossil-fuel CO<span class="inline-formula"><sub>2</sub></span> release scenarios. In the natural scenario, the model assigns high probability of occurrence of long interglacials in the periods between the present and 120 kyr after present and between 400 and 500 kyr after present. The next glacial inception is most likely to occur <span class="inline-formula">∼50</span> kyr after present with full glacial conditions developing <span class="inline-formula">∼90</span> kyr after present. The model shows that even already achieved cumulative CO<span class="inline-formula"><sub>2</sub></span> anthropogenic emissions (500 Pg C) are capable of affecting the climate evolution for up to half a million years, indicating that the beginning of the next glaciation is highly unlikely in the next 120 kyr. High cumulative anthropogenic CO<span class="inline-formula"><sub>2</sub></span> emissions (3000 Pg C or higher), which could potentially be achieved in the next 2 to 3 centuries if humanity does not curb the usage of fossil fuels, will most likely provoke Northern Hemisphere landmass ice-free conditions throughout the next half a million years, postponing the natural occurrence of the next glacial inception to 600 kyr after present or later.</p>https://esd.copernicus.org/articles/12/1275/2021/esd-12-1275-2021.pdf |
| spellingShingle | S. Talento A. Ganopolski Reduced-complexity model for the impact of anthropogenic CO<sub>2</sub> emissions on future glacial cycles Earth System Dynamics |
| title | Reduced-complexity model for the impact of anthropogenic CO<sub>2</sub> emissions on future glacial cycles |
| title_full | Reduced-complexity model for the impact of anthropogenic CO<sub>2</sub> emissions on future glacial cycles |
| title_fullStr | Reduced-complexity model for the impact of anthropogenic CO<sub>2</sub> emissions on future glacial cycles |
| title_full_unstemmed | Reduced-complexity model for the impact of anthropogenic CO<sub>2</sub> emissions on future glacial cycles |
| title_short | Reduced-complexity model for the impact of anthropogenic CO<sub>2</sub> emissions on future glacial cycles |
| title_sort | reduced complexity model for the impact of anthropogenic co sub 2 sub emissions on future glacial cycles |
| url | https://esd.copernicus.org/articles/12/1275/2021/esd-12-1275-2021.pdf |
| work_keys_str_mv | AT stalento reducedcomplexitymodelfortheimpactofanthropogeniccosub2subemissionsonfutureglacialcycles AT aganopolski reducedcomplexitymodelfortheimpactofanthropogeniccosub2subemissionsonfutureglacialcycles |