Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance
Stable, steady climate states on an Earth-size planet with no continents are determined as a function of the tilt of the planet's rotation axis (obliquity) and stellar irradiance. Using a general circulation model of the atmosphere coupled to a slab ocean and a thermodynamic sea ice model, two...
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ftunivbern:oai:boris.unibe.ch:106535 2023-08-20T04:09:45+02:00 Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance Kilic, Cevahir Raible, Christoph Stocker, Thomas 2017 application/pdf https://boris.unibe.ch/106535/1/kilic17apj.pdf https://boris.unibe.ch/106535/ eng eng Institute of Physics Publishing IOP https://boris.unibe.ch/106535/ info:eu-repo/semantics/openAccess Kilic, Cevahir; Raible, Christoph; Stocker, Thomas (2017). Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance. Astrophysical journal, 844(2), p. 147. Institute of Physics Publishing IOP 10.3847/1538-4357/aa7a03 <http://dx.doi.org/10.3847/1538-4357/aa7a03> 530 Physics 520 Astronomy info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion PeerReviewed 2017 ftunivbern https://doi.org/10.3847/1538-4357/aa7a03 2023-07-31T21:38:24Z Stable, steady climate states on an Earth-size planet with no continents are determined as a function of the tilt of the planet's rotation axis (obliquity) and stellar irradiance. Using a general circulation model of the atmosphere coupled to a slab ocean and a thermodynamic sea ice model, two states, the Aquaplanet and the Cryoplanet, are found for high and low stellar irradiance, respectively. In addition, four stable states with seasonally and perennially open water are discovered if comprehensively exploring a parameter space of obliquity from 0° to 90° and stellar irradiance from 70% to 135% of the present-day solar constant. Within 11% of today's solar irradiance, we find a rich structure of stable states that extends the area of habitability considerably. For the same set of parameters, different stable states result if simulations are initialized from an aquaplanet or a cryoplanet state. This demonstrates the possibility of multiple equilibria, hysteresis, and potentially rapid climate change in response to small changes in the orbital parameters. The dynamics of the atmosphere of an aquaplanet or a cryoplanet state is investigated for similar values of obliquity and stellar irradiance. The atmospheric circulation substantially differs in the two states owing to the relative strength of the primary drivers of the meridional transport of heat and momentum. At 90° obliquity and present-day solar constant, the atmospheric dynamics of an Aquaplanet state and one with an equatorial ice cover is analyzed. Article in Journal/Newspaper Sea ice BORIS (Bern Open Repository and Information System, University of Bern) The Astrophysical Journal 844 2 147 |
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BORIS (Bern Open Repository and Information System, University of Bern) |
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ftunivbern |
language |
English |
topic |
530 Physics 520 Astronomy |
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530 Physics 520 Astronomy Kilic, Cevahir Raible, Christoph Stocker, Thomas Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance |
topic_facet |
530 Physics 520 Astronomy |
description |
Stable, steady climate states on an Earth-size planet with no continents are determined as a function of the tilt of the planet's rotation axis (obliquity) and stellar irradiance. Using a general circulation model of the atmosphere coupled to a slab ocean and a thermodynamic sea ice model, two states, the Aquaplanet and the Cryoplanet, are found for high and low stellar irradiance, respectively. In addition, four stable states with seasonally and perennially open water are discovered if comprehensively exploring a parameter space of obliquity from 0° to 90° and stellar irradiance from 70% to 135% of the present-day solar constant. Within 11% of today's solar irradiance, we find a rich structure of stable states that extends the area of habitability considerably. For the same set of parameters, different stable states result if simulations are initialized from an aquaplanet or a cryoplanet state. This demonstrates the possibility of multiple equilibria, hysteresis, and potentially rapid climate change in response to small changes in the orbital parameters. The dynamics of the atmosphere of an aquaplanet or a cryoplanet state is investigated for similar values of obliquity and stellar irradiance. The atmospheric circulation substantially differs in the two states owing to the relative strength of the primary drivers of the meridional transport of heat and momentum. At 90° obliquity and present-day solar constant, the atmospheric dynamics of an Aquaplanet state and one with an equatorial ice cover is analyzed. |
format |
Article in Journal/Newspaper |
author |
Kilic, Cevahir Raible, Christoph Stocker, Thomas |
author_facet |
Kilic, Cevahir Raible, Christoph Stocker, Thomas |
author_sort |
Kilic, Cevahir |
title |
Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance |
title_short |
Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance |
title_full |
Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance |
title_fullStr |
Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance |
title_full_unstemmed |
Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance |
title_sort |
multiple climate states of habitable exoplanets: the role of obliquity and irradiance |
publisher |
Institute of Physics Publishing IOP |
publishDate |
2017 |
url |
https://boris.unibe.ch/106535/1/kilic17apj.pdf https://boris.unibe.ch/106535/ |
genre |
Sea ice |
genre_facet |
Sea ice |
op_source |
Kilic, Cevahir; Raible, Christoph; Stocker, Thomas (2017). Multiple Climate States of Habitable Exoplanets: The Role of Obliquity and Irradiance. Astrophysical journal, 844(2), p. 147. Institute of Physics Publishing IOP 10.3847/1538-4357/aa7a03 <http://dx.doi.org/10.3847/1538-4357/aa7a03> |
op_relation |
https://boris.unibe.ch/106535/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.3847/1538-4357/aa7a03 |
container_title |
The Astrophysical Journal |
container_volume |
844 |
container_issue |
2 |
container_start_page |
147 |
_version_ |
1774723424732577792 |