Comparison of land–ocean warming ratios in updated observed records and CMIP5 climate models
A well-known feature of the observed and simulated climate is enhanced land surface warming compared to the ocean. This difference in warming, frequently expressed as a ratio, is often contrasted between the observed record and climate model output as both an evaluation metric for climate models and...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2018-01-01
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| Series: | Environmental Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1748-9326/aae46f |
| _version_ | 1797748140719210496 |
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| author | C J Wallace M Joshi |
| author_facet | C J Wallace M Joshi |
| author_sort | C J Wallace |
| collection | DOAJ |
| description | A well-known feature of the observed and simulated climate is enhanced land surface warming compared to the ocean. This difference in warming, frequently expressed as a ratio, is often contrasted between the observed record and climate model output as both an evaluation metric for climate models and as a global index used for climate change detection and attribution. Latest simulated estimates of the ratio use full global coverage and marine surface air temperature, making genuine comparisons with observations difficult, since global observed data sets typically use sea surface temperatures (SST) and have limited spatial coverage. We show that re-calculating simulated ratios using SST and limited spatial coverage (to resemble the observations) raises the ratio by ∼0.25. We also update the observed ratio using latest observations and we find a close convergence of observed and simulated ratios towards ∼1.6 for the 2000–2016 period accompanied by a decline in temporal variability. If we revise estimates of the likely range of ratios from climate models to account for the above factors, then our new observed ratio estimate is slightly less than the median of the GCM ensemble range (1.54–1.81). |
| first_indexed | 2024-03-12T16:00:37Z |
| format | Article |
| id | doaj.art-6866d23c75534053b67abbaee3cfbb1c |
| institution | Directory Open Access Journal |
| issn | 1748-9326 |
| language | English |
| last_indexed | 2024-03-12T16:00:37Z |
| publishDate | 2018-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | Environmental Research Letters |
| spelling | doaj.art-6866d23c75534053b67abbaee3cfbb1c2023-08-09T14:38:27ZengIOP PublishingEnvironmental Research Letters1748-93262018-01-01131111401110.1088/1748-9326/aae46fComparison of land–ocean warming ratios in updated observed records and CMIP5 climate modelsC J Wallace0https://orcid.org/0000-0002-4684-8248M Joshi1Climatic Research Unit, School of Environmental Science, University of East Anglia , Norwich, NR4 7TJ, United KingdomClimatic Research Unit, School of Environmental Science, University of East Anglia , Norwich, NR4 7TJ, United KingdomA well-known feature of the observed and simulated climate is enhanced land surface warming compared to the ocean. This difference in warming, frequently expressed as a ratio, is often contrasted between the observed record and climate model output as both an evaluation metric for climate models and as a global index used for climate change detection and attribution. Latest simulated estimates of the ratio use full global coverage and marine surface air temperature, making genuine comparisons with observations difficult, since global observed data sets typically use sea surface temperatures (SST) and have limited spatial coverage. We show that re-calculating simulated ratios using SST and limited spatial coverage (to resemble the observations) raises the ratio by ∼0.25. We also update the observed ratio using latest observations and we find a close convergence of observed and simulated ratios towards ∼1.6 for the 2000–2016 period accompanied by a decline in temporal variability. If we revise estimates of the likely range of ratios from climate models to account for the above factors, then our new observed ratio estimate is slightly less than the median of the GCM ensemble range (1.54–1.81).https://doi.org/10.1088/1748-9326/aae46fclimate changeland warmingocean warmingclimate modelclimate observations |
| spellingShingle | C J Wallace M Joshi Comparison of land–ocean warming ratios in updated observed records and CMIP5 climate models Environmental Research Letters climate change land warming ocean warming climate model climate observations |
| title | Comparison of land–ocean warming ratios in updated observed records and CMIP5 climate models |
| title_full | Comparison of land–ocean warming ratios in updated observed records and CMIP5 climate models |
| title_fullStr | Comparison of land–ocean warming ratios in updated observed records and CMIP5 climate models |
| title_full_unstemmed | Comparison of land–ocean warming ratios in updated observed records and CMIP5 climate models |
| title_short | Comparison of land–ocean warming ratios in updated observed records and CMIP5 climate models |
| title_sort | comparison of land ocean warming ratios in updated observed records and cmip5 climate models |
| topic | climate change land warming ocean warming climate model climate observations |
| url | https://doi.org/10.1088/1748-9326/aae46f |
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