Scaling of the entropy budget with surface temperature in radiative-convective equilibrium
The entropy budget of the atmosphere is examined in simulations of radiative-convective equilibrium with a cloud-system resolving model over a wide range of surface temperatures from 281 to 311 K. Irreversible phase changes and the diffusion of water vapor account for more than half of the irreversi...
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| Format: | Article |
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American Geophysical Union (AGU)
2018
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| Online Access: | http://hdl.handle.net/1721.1/118589 https://orcid.org/0000-0003-1748-0816 |
| _version_ | 1826195450267435008 |
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| author | Singh, Martin S. O'Gorman, Paul |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Singh, Martin S. O'Gorman, Paul |
| author_sort | Singh, Martin S. |
| collection | MIT |
| description | The entropy budget of the atmosphere is examined in simulations of radiative-convective equilibrium with a cloud-system resolving model over a wide range of surface temperatures from 281 to 311 K. Irreversible phase changes and the diffusion of water vapor account for more than half of the irreversible entropy production within the atmosphere, even in the coldest simulation. As the surface temperature is increased, the atmospheric radiative cooling rate increases, driving a greater entropy sink that must be matched by greater irreversible entropy production. The entropy production resulting from irreversible moist processes increases at a similar fractional rate as the entropy sink and at a lower rate than that implied by Clausius-Clapeyron scaling. This allows the entropy production from frictional drag on hydrometeors and on the atmospheric flow to also increase with warming, in contrast to recent results for simulations with global climate models in which the work output decreases with warming. A set of approximate scaling relations is introduced for the terms in the entropy budget as the surface temperature is varied, and many of the terms are found to scale with the mean surface precipitation rate. The entropy budget provides some insight into changes in frictional dissipation in response to warming or changes in model resolution, but it is argued that frictional dissipation is not closely linked to other measures of convective vigor. |
| first_indexed | 2024-09-23T10:12:53Z |
| format | Article |
| id | mit-1721.1/118589 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T10:12:53Z |
| publishDate | 2018 |
| publisher | American Geophysical Union (AGU) |
| record_format | dspace |
| spelling | mit-1721.1/1185892022-09-26T16:32:00Z Scaling of the entropy budget with surface temperature in radiative-convective equilibrium Singh, Martin S. O'Gorman, Paul Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences O'Gorman, Paul The entropy budget of the atmosphere is examined in simulations of radiative-convective equilibrium with a cloud-system resolving model over a wide range of surface temperatures from 281 to 311 K. Irreversible phase changes and the diffusion of water vapor account for more than half of the irreversible entropy production within the atmosphere, even in the coldest simulation. As the surface temperature is increased, the atmospheric radiative cooling rate increases, driving a greater entropy sink that must be matched by greater irreversible entropy production. The entropy production resulting from irreversible moist processes increases at a similar fractional rate as the entropy sink and at a lower rate than that implied by Clausius-Clapeyron scaling. This allows the entropy production from frictional drag on hydrometeors and on the atmospheric flow to also increase with warming, in contrast to recent results for simulations with global climate models in which the work output decreases with warming. A set of approximate scaling relations is introduced for the terms in the entropy budget as the surface temperature is varied, and many of the terms are found to scale with the mean surface precipitation rate. The entropy budget provides some insight into changes in frictional dissipation in response to warming or changes in model resolution, but it is argued that frictional dissipation is not closely linked to other measures of convective vigor. 2018-10-16T18:39:26Z 2018-10-16T18:39:26Z 2016-07 2016-03 2018-09-27T16:42:28Z Article http://purl.org/eprint/type/JournalArticle 1942-2466 http://hdl.handle.net/1721.1/118589 Singh, Martin S. et al. “Scaling of the Entropy Budget with Surface Temperature in Radiative-Convective Equilibrium.” Journal of Advances in Modeling Earth Systems 8, 3 (July 2016): 1132–1150 © 2016 The Authors https://orcid.org/0000-0003-1748-0816 http://dx.doi.org/10.1002/2016MS000673 Journal of Advances in Modeling Earth Systems Creative Commons Attribution-NonCommercial-NoDerivs License http://creativecommons.org/licenses/by-nc-nd/4.0/ application/pdf American Geophysical Union (AGU) Wiley |
| spellingShingle | Singh, Martin S. O'Gorman, Paul Scaling of the entropy budget with surface temperature in radiative-convective equilibrium |
| title | Scaling of the entropy budget with surface temperature in radiative-convective equilibrium |
| title_full | Scaling of the entropy budget with surface temperature in radiative-convective equilibrium |
| title_fullStr | Scaling of the entropy budget with surface temperature in radiative-convective equilibrium |
| title_full_unstemmed | Scaling of the entropy budget with surface temperature in radiative-convective equilibrium |
| title_short | Scaling of the entropy budget with surface temperature in radiative-convective equilibrium |
| title_sort | scaling of the entropy budget with surface temperature in radiative convective equilibrium |
| url | http://hdl.handle.net/1721.1/118589 https://orcid.org/0000-0003-1748-0816 |
| work_keys_str_mv | AT singhmartins scalingoftheentropybudgetwithsurfacetemperatureinradiativeconvectiveequilibrium AT ogormanpaul scalingoftheentropybudgetwithsurfacetemperatureinradiativeconvectiveequilibrium |