Projected increase in continental runoff due to plant responses to increasing carbon dioxide.
| Title: | Projected increase in continental runoff due to plant responses to increasing carbon dioxide. |
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| Authors: | Betts RA; Met Office Hadley Centre, Fitzroy Road, Exeter EX1 3PB, UK. richard.betts@metoffice.gov.uk; Boucher O; Collins M; Cox PM; Falloon PD; Gedney N; Hemming DL; Huntingford C; Jones CD; Sexton DM; Webb MJ |
| Source: | Nature [Nature] 2007 Aug 30; Vol. 448 (7157), pp. 1037-41. |
| Publication Type: | Journal Article; Research Support, Non-U.S. Gov't |
| Language: | English |
| Journal Info: | Publisher: Nature Publishing Group Country of Publication: England NLM ID: 0410462 Publication Model: Print Cited Medium: Internet ISSN: 1476-4687 (Electronic) Linking ISSN: 00280836 NLM ISO Abbreviation: Nature Subsets: MEDLINE |
| Imprint Name(s): | Publication: Basingstoke : Nature Publishing Group; Original Publication: London, Macmillan Journals ltd. |
| MeSH Terms: | Greenhouse Effect* ; Rain*; Carbon Dioxide/*metabolism ; Plants/*metabolism ; Water/*analysis; Water/metabolism ; Models, Biological ; Photosynthesis ; Plant Transpiration ; Temperature |
| Abstract: | In addition to influencing climatic conditions directly through radiative forcing, increasing carbon dioxide concentration influences the climate system through its effects on plant physiology. Plant stomata generally open less widely under increased carbon dioxide concentration, which reduces transpiration and thus leaves more water at the land surface. This driver of change in the climate system, which we term 'physiological forcing', has been detected in observational records of increasing average continental runoff over the twentieth century. Here we use an ensemble of experiments with a global climate model that includes a vegetation component to assess the contribution of physiological forcing to future changes in continental runoff, in the context of uncertainties in future precipitation. We find that the physiological effect of doubled carbon dioxide concentrations on plant transpiration increases simulated global mean runoff by 6 per cent relative to pre-industrial levels; an increase that is comparable to that simulated in response to radiatively forced climate change (11 +/- 6 per cent). Assessments of the effect of increasing carbon dioxide concentrations on the hydrological cycle that only consider radiative forcing will therefore tend to underestimate future increases in runoff and overestimate decreases. This suggests that freshwater resources may be less limited than previously assumed under scenarios of future global warming, although there is still an increased risk of drought. Moreover, our results highlight that the practice of assessing the climate-forcing potential of all greenhouse gases in terms of their radiative forcing potential relative to carbon dioxide does not accurately reflect the relative effects of different greenhouse gases on freshwater resources. |
| Substance Nomenclature: | 059QF0KO0R (Water); 142M471B3J (Carbon Dioxide) |
| Entry Date(s): | Date Created: 20070831 Date Completed: 20070928 Latest Revision: 20220330 |
| Update Code: | 20260130 |
| DOI: | 10.1038/nature06045 |
| PMID: | 17728755 |
| Database: | MEDLINE |
Journal Article; Research Support, Non-U.S. Gov't