On the increased climate sensitivity in the EC-Earth model from CMIP5 to CMIP6
<p>Many modelling groups that contribute to CMIP6 (Coupled Model Intercomparison Project Phase 6) have found a larger equilibrium climate sensitivity (ECS) with their latest model versions compared with the values obtained with the earlier versions used in CMIP5. This is also the case for the...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2020-08-01
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| Series: | Geoscientific Model Development |
| Online Access: | https://gmd.copernicus.org/articles/13/3465/2020/gmd-13-3465-2020.pdf |
| _version_ | 1818042938996817920 |
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| author | K. Wyser T. van Noije S. Yang J. von Hardenberg J. von Hardenberg D. O'Donnell R. Döscher |
| author_facet | K. Wyser T. van Noije S. Yang J. von Hardenberg J. von Hardenberg D. O'Donnell R. Döscher |
| author_sort | K. Wyser |
| collection | DOAJ |
| description | <p>Many modelling groups that contribute to CMIP6 (Coupled
Model Intercomparison Project Phase 6) have found a larger equilibrium
climate sensitivity (ECS) with their latest model versions compared with the
values obtained with the earlier versions used in CMIP5. This is also the case for
the EC-Earth model. Therefore, in this study, we investigate what developments since
the CMIP5 era could have caused the increase in the ECS in this model. Apart
from increases in the horizontal and vertical resolution, the EC-Earth model has also substantially changed the representation of aerosols; in
particular, it has introduced a more sophisticated description of aerosol
indirect effects. After testing the model with some of the recent updates
switched off, we find that the ECS increase can be attributed to the more
advanced treatment of aerosols, with the largest contribution coming from
the effect of aerosols on cloud microphysics (cloud lifetime or second
indirect effect). The increase in climate sensitivity is unrelated to model
tuning, as all experiments were performed with the same tuning
parameters and only the representation of the aerosol effects was
changed. These results cannot be generalised to other models, as their CMIP5
and CMIP6 versions may differ with respect to aspects other than the aerosol–cloud
interaction, but the results highlight the strong sensitivity of ECS to the
details of the aerosol forcing.</p> |
| first_indexed | 2024-12-10T08:54:17Z |
| format | Article |
| id | doaj.art-cab0e9ec3dc545d3aa511d18c1ba4199 |
| institution | Directory Open Access Journal |
| issn | 1991-959X 1991-9603 |
| language | English |
| last_indexed | 2024-12-10T08:54:17Z |
| publishDate | 2020-08-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Geoscientific Model Development |
| spelling | doaj.art-cab0e9ec3dc545d3aa511d18c1ba41992022-12-22T01:55:29ZengCopernicus PublicationsGeoscientific Model Development1991-959X1991-96032020-08-01133465347410.5194/gmd-13-3465-2020On the increased climate sensitivity in the EC-Earth model from CMIP5 to CMIP6K. Wyser0T. van Noije1S. Yang2J. von Hardenberg3J. von Hardenberg4D. O'Donnell5R. Döscher6Rossby Centre, Swedish Meteorological and Hydrological Institute (SMHI), 601 76 Norrköping, SwedenRoyal Netherlands Meteorological Institute, 3730 AE De Bilt, the NetherlandsDanish Meteorological Institute (DMI), 2100 Copenhagen, DenmarkDepartment of Environment, Land and Infrastructure Engineering, Politecnico di Torino, 10129 Turin, ItalyInstitute of Atmospheric Sciences and Climate, Consiglio Nazionale delle Ricerche (ISAC-CNR), 10133 Turin, ItalyFinnish Meteorological Institute, 00560 Helsinki, FinlandRossby Centre, Swedish Meteorological and Hydrological Institute (SMHI), 601 76 Norrköping, Sweden<p>Many modelling groups that contribute to CMIP6 (Coupled Model Intercomparison Project Phase 6) have found a larger equilibrium climate sensitivity (ECS) with their latest model versions compared with the values obtained with the earlier versions used in CMIP5. This is also the case for the EC-Earth model. Therefore, in this study, we investigate what developments since the CMIP5 era could have caused the increase in the ECS in this model. Apart from increases in the horizontal and vertical resolution, the EC-Earth model has also substantially changed the representation of aerosols; in particular, it has introduced a more sophisticated description of aerosol indirect effects. After testing the model with some of the recent updates switched off, we find that the ECS increase can be attributed to the more advanced treatment of aerosols, with the largest contribution coming from the effect of aerosols on cloud microphysics (cloud lifetime or second indirect effect). The increase in climate sensitivity is unrelated to model tuning, as all experiments were performed with the same tuning parameters and only the representation of the aerosol effects was changed. These results cannot be generalised to other models, as their CMIP5 and CMIP6 versions may differ with respect to aspects other than the aerosol–cloud interaction, but the results highlight the strong sensitivity of ECS to the details of the aerosol forcing.</p>https://gmd.copernicus.org/articles/13/3465/2020/gmd-13-3465-2020.pdf |
| spellingShingle | K. Wyser T. van Noije S. Yang J. von Hardenberg J. von Hardenberg D. O'Donnell R. Döscher On the increased climate sensitivity in the EC-Earth model from CMIP5 to CMIP6 Geoscientific Model Development |
| title | On the increased climate sensitivity in the EC-Earth model from CMIP5 to CMIP6 |
| title_full | On the increased climate sensitivity in the EC-Earth model from CMIP5 to CMIP6 |
| title_fullStr | On the increased climate sensitivity in the EC-Earth model from CMIP5 to CMIP6 |
| title_full_unstemmed | On the increased climate sensitivity in the EC-Earth model from CMIP5 to CMIP6 |
| title_short | On the increased climate sensitivity in the EC-Earth model from CMIP5 to CMIP6 |
| title_sort | on the increased climate sensitivity in the ec earth model from cmip5 to cmip6 |
| url | https://gmd.copernicus.org/articles/13/3465/2020/gmd-13-3465-2020.pdf |
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