Emit now, mitigate later? Earth system reversibility under overshoots of different magnitude and duration
Reversibility is, next to socio-economic feasibility and sustainability, key for assessing if carbon dioxide removal (CDR) could be considered to return the Earth system to a less dangerous state after a period of temperature overshoot above a level that is considered safe. Here, we use a state-of-t...
Main Authors: | , , , |
---|---|
Format: | Text |
Language: | English |
Published: |
2022
|
Subjects: | |
Online Access: | https://doi.org/10.5194/esd-2022-39 https://esd.copernicus.org/preprints/esd-2022-39/ |
id |
ftcopernicus:oai:publications.copernicus.org:esdd105512 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:esdd105512 2023-05-15T17:57:12+02:00 Emit now, mitigate later? Earth system reversibility under overshoots of different magnitude and duration Schwinger, Jörg Asaadi, Ali Steinert, Norman Julius Lee, Hanna 2022-08-22 application/pdf https://doi.org/10.5194/esd-2022-39 https://esd.copernicus.org/preprints/esd-2022-39/ eng eng doi:10.5194/esd-2022-39 https://esd.copernicus.org/preprints/esd-2022-39/ eISSN: 2190-4987 Text 2022 ftcopernicus https://doi.org/10.5194/esd-2022-39 2022-08-29T16:22:55Z Reversibility is, next to socio-economic feasibility and sustainability, key for assessing if carbon dioxide removal (CDR) could be considered to return the Earth system to a less dangerous state after a period of temperature overshoot above a level that is considered safe. Here, we use a state-of-the-art Earth system model that includes a representation of permafrost carbon to investigate the reversibility of the Earth system after overshoots of different duration and magnitude in idealized simulations. We find that atmospheric CO 2 concentrations are slightly lower after an overshoot, compared to a reference simulation without overshoot, due to a near-perfect compensation of carbon losses from land by increased ocean carbon uptake during the overshoot periods. Many aspects of the Earth system including global average surface temperature, marine and terrestrial productivity, strength of the Atlantic meridional overturning circulation, surface ocean pH, surface O 2 concentration, and permafrost extent are reversible on a centennial time scale except in the most extreme overshoot scenario considered in this study. Consistent with previous studies, we find irreversibility for permafrost carbon and deep ocean properties like sea water temperature, pH, and O 2 concentrations. We do not find any indication of tipping points or self-reinforcing feedbacks that would put the Earth system on a significantly different trajectory after an overshoot. Hence, irreversibility might not be the main issue of CDR but rather the impacts and risks that would occur during the period of elevated temperatures during the overshoot. Text permafrost Copernicus Publications: E-Journals |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
Reversibility is, next to socio-economic feasibility and sustainability, key for assessing if carbon dioxide removal (CDR) could be considered to return the Earth system to a less dangerous state after a period of temperature overshoot above a level that is considered safe. Here, we use a state-of-the-art Earth system model that includes a representation of permafrost carbon to investigate the reversibility of the Earth system after overshoots of different duration and magnitude in idealized simulations. We find that atmospheric CO 2 concentrations are slightly lower after an overshoot, compared to a reference simulation without overshoot, due to a near-perfect compensation of carbon losses from land by increased ocean carbon uptake during the overshoot periods. Many aspects of the Earth system including global average surface temperature, marine and terrestrial productivity, strength of the Atlantic meridional overturning circulation, surface ocean pH, surface O 2 concentration, and permafrost extent are reversible on a centennial time scale except in the most extreme overshoot scenario considered in this study. Consistent with previous studies, we find irreversibility for permafrost carbon and deep ocean properties like sea water temperature, pH, and O 2 concentrations. We do not find any indication of tipping points or self-reinforcing feedbacks that would put the Earth system on a significantly different trajectory after an overshoot. Hence, irreversibility might not be the main issue of CDR but rather the impacts and risks that would occur during the period of elevated temperatures during the overshoot. |
format |
Text |
author |
Schwinger, Jörg Asaadi, Ali Steinert, Norman Julius Lee, Hanna |
spellingShingle |
Schwinger, Jörg Asaadi, Ali Steinert, Norman Julius Lee, Hanna Emit now, mitigate later? Earth system reversibility under overshoots of different magnitude and duration |
author_facet |
Schwinger, Jörg Asaadi, Ali Steinert, Norman Julius Lee, Hanna |
author_sort |
Schwinger, Jörg |
title |
Emit now, mitigate later? Earth system reversibility under overshoots of different magnitude and duration |
title_short |
Emit now, mitigate later? Earth system reversibility under overshoots of different magnitude and duration |
title_full |
Emit now, mitigate later? Earth system reversibility under overshoots of different magnitude and duration |
title_fullStr |
Emit now, mitigate later? Earth system reversibility under overshoots of different magnitude and duration |
title_full_unstemmed |
Emit now, mitigate later? Earth system reversibility under overshoots of different magnitude and duration |
title_sort |
emit now, mitigate later? earth system reversibility under overshoots of different magnitude and duration |
publishDate |
2022 |
url |
https://doi.org/10.5194/esd-2022-39 https://esd.copernicus.org/preprints/esd-2022-39/ |
genre |
permafrost |
genre_facet |
permafrost |
op_source |
eISSN: 2190-4987 |
op_relation |
doi:10.5194/esd-2022-39 https://esd.copernicus.org/preprints/esd-2022-39/ |
op_doi |
https://doi.org/10.5194/esd-2022-39 |
_version_ |
1766165588491632640 |