Evaluating climate model performance with various parameter sets using observations over the recent past
Many sources of uncertainty limit the accuracy of climate projections. Among them, we focus here on the parameter uncertainty, i.e. the imperfect knowledge of the values of many physical parameters in a climate model. Therefore, we use LOVECLIM, a global three-dimensional Earth system model of inter...
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ftvliz:oai:oma.vliz.be:296052 2023-05-15T17:32:37+02:00 Evaluating climate model performance with various parameter sets using observations over the recent past Loutre, M.-F. Mouchet, A. Fichefet, T. Goosse, H. Goelzer, H. Huybrechts, P. 2011 application/pdf https://www.vliz.be/imisdocs/publications/314865.pdf en eng info:eu-repo/semantics/altIdentifier/wos/000292247800012 info:eu-repo/semantics/altIdentifier/doi/doi.org/10.5194/cp-7-511-2011 https://www.vliz.be/imisdocs/publications/314865.pdf info:eu-repo/semantics/openAccess %3Ci%3EClim.+Past+7%282%29%3C%2Fi%3E%3A+511-526.+%3Ca+href%3D%22https%3A%2F%2Fdx.doi.org%2F10.5194%2Fcp-7-511-2011%22+target%3D%22_blank%22%3Ehttps%3A%2F%2Fdx.doi.org%2F10.5194%2Fcp-7-511-2011%3C%2Fa%3E info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2011 ftvliz https://doi.org/10.5194/cp-7-511-2011 2022-05-01T11:00:35Z Many sources of uncertainty limit the accuracy of climate projections. Among them, we focus here on the parameter uncertainty, i.e. the imperfect knowledge of the values of many physical parameters in a climate model. Therefore, we use LOVECLIM, a global three-dimensional Earth system model of intermediate complexity and vary several parameters within a range based on the expert judgement of model developers. Nine climatic parameter sets and three carbon cycle parameter sets are selected because they yield present-day climate simulations coherent with observations and they cover a wide range of climate responses to doubled atmospheric CO2 concentration and freshwater flux perturbation in the North Atlantic. Moreover, they also lead to a large range of atmospheric CO2 concentrations in response to prescribed emissions. Consequently, we have at our disposal 27 alternative versions of LOVECLIM (each corresponding to one parameter set) that provide very different responses to some climate forcings. The 27 model versions are then used to illustrate the range of responses provided over the recent past, to compare the time evolution of climate variables over the time interval for which they are available (the last few decades up to more than one century) and to identify the outliers and the "best" versions over that particular time span. For example, between 1979 and 2005, the simulated global annual mean surface temperature increase ranges from 0.24 degrees C to 0.64 degrees C, while the simulated increase in atmospheric CO2 concentration varies between 40 and 50 ppmv. Measurements over the same period indicate an increase in global annual mean surface temperature of 0.45 degrees C (Brohan et al., 2006) and an increase in atmospheric CO2 concentration of 44 ppmv (Enting et al., 1994; GLOBALVIEW-CO2, 2006). Only a few parameter sets yield simulations that reproduce the observed key variables of the climate system over the last decades. Furthermore, our results show that the model response, including its ocean component, is strongly influenced by the model sensitivity to an increase in atmospheric CO2 concentration but much less by its sensitivity to freshwater flux in the North Atlantic. They also highlight weaknesses of the model, in particular its large ocean heat uptake. Article in Journal/Newspaper North Atlantic Flanders Marine Institute (VLIZ): Open Marine Archive (OMA) Climate of the Past 7 2 511 526 |
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Open Polar |
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Flanders Marine Institute (VLIZ): Open Marine Archive (OMA) |
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ftvliz |
language |
English |
description |
Many sources of uncertainty limit the accuracy of climate projections. Among them, we focus here on the parameter uncertainty, i.e. the imperfect knowledge of the values of many physical parameters in a climate model. Therefore, we use LOVECLIM, a global three-dimensional Earth system model of intermediate complexity and vary several parameters within a range based on the expert judgement of model developers. Nine climatic parameter sets and three carbon cycle parameter sets are selected because they yield present-day climate simulations coherent with observations and they cover a wide range of climate responses to doubled atmospheric CO2 concentration and freshwater flux perturbation in the North Atlantic. Moreover, they also lead to a large range of atmospheric CO2 concentrations in response to prescribed emissions. Consequently, we have at our disposal 27 alternative versions of LOVECLIM (each corresponding to one parameter set) that provide very different responses to some climate forcings. The 27 model versions are then used to illustrate the range of responses provided over the recent past, to compare the time evolution of climate variables over the time interval for which they are available (the last few decades up to more than one century) and to identify the outliers and the "best" versions over that particular time span. For example, between 1979 and 2005, the simulated global annual mean surface temperature increase ranges from 0.24 degrees C to 0.64 degrees C, while the simulated increase in atmospheric CO2 concentration varies between 40 and 50 ppmv. Measurements over the same period indicate an increase in global annual mean surface temperature of 0.45 degrees C (Brohan et al., 2006) and an increase in atmospheric CO2 concentration of 44 ppmv (Enting et al., 1994; GLOBALVIEW-CO2, 2006). Only a few parameter sets yield simulations that reproduce the observed key variables of the climate system over the last decades. Furthermore, our results show that the model response, including its ocean component, is strongly influenced by the model sensitivity to an increase in atmospheric CO2 concentration but much less by its sensitivity to freshwater flux in the North Atlantic. They also highlight weaknesses of the model, in particular its large ocean heat uptake. |
format |
Article in Journal/Newspaper |
author |
Loutre, M.-F. Mouchet, A. Fichefet, T. Goosse, H. Goelzer, H. Huybrechts, P. |
spellingShingle |
Loutre, M.-F. Mouchet, A. Fichefet, T. Goosse, H. Goelzer, H. Huybrechts, P. Evaluating climate model performance with various parameter sets using observations over the recent past |
author_facet |
Loutre, M.-F. Mouchet, A. Fichefet, T. Goosse, H. Goelzer, H. Huybrechts, P. |
author_sort |
Loutre, M.-F. |
title |
Evaluating climate model performance with various parameter sets using observations over the recent past |
title_short |
Evaluating climate model performance with various parameter sets using observations over the recent past |
title_full |
Evaluating climate model performance with various parameter sets using observations over the recent past |
title_fullStr |
Evaluating climate model performance with various parameter sets using observations over the recent past |
title_full_unstemmed |
Evaluating climate model performance with various parameter sets using observations over the recent past |
title_sort |
evaluating climate model performance with various parameter sets using observations over the recent past |
publishDate |
2011 |
url |
https://www.vliz.be/imisdocs/publications/314865.pdf |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
%3Ci%3EClim.+Past+7%282%29%3C%2Fi%3E%3A+511-526.+%3Ca+href%3D%22https%3A%2F%2Fdx.doi.org%2F10.5194%2Fcp-7-511-2011%22+target%3D%22_blank%22%3Ehttps%3A%2F%2Fdx.doi.org%2F10.5194%2Fcp-7-511-2011%3C%2Fa%3E |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/000292247800012 info:eu-repo/semantics/altIdentifier/doi/doi.org/10.5194/cp-7-511-2011 https://www.vliz.be/imisdocs/publications/314865.pdf |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/cp-7-511-2011 |
container_title |
Climate of the Past |
container_volume |
7 |
container_issue |
2 |
container_start_page |
511 |
op_container_end_page |
526 |
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1766130810696499200 |