Emission scenario dependencies in climate change assessments of the hydrological cycle
- 324 Downloads
Anthropogenic global warming will lead to changes in the global hydrological cycle. The uncertainty in precipitation sensitivity per 1 K of global warming across coupled atmosphere-ocean general circulation models (AOGCMs) has been actively examined. On the other hand, the uncertainty in precipitation sensitivity in different emission scenarios of greenhouse gases (GHGs) and aerosols has received little attention. Here we show a robust emission-scenario dependency (ESD); smaller global precipitation sensitivities occur in higher GHG and aerosol emission scenarios. Although previous studies have applied this ESD to the multi-AOGCM mean, our surprising finding is that current AOGCMs all have the common ESD in the same direction. Different aerosol emissions lead to this ESD. The implications of the ESD of precipitation sensitivity extend far beyond climate analyses. As we show, the ESD potentially propagates into considerable biases in impact assessments of the hydrological cycle via a widely used technique, so-called pattern scaling. Since pattern scaling is essential to conducting parallel analyses across climate, impact, adaptation and mitigation scenarios in the next report from the Intergovernmental Panel on Climate Change, more attention should be paid to the ESD of precipitation sensitivity.
Unable to display preview. Download preview PDF.
- Hanasaki N et al (2008) An integrated model for the assessment of global water resources – part 1: model description and input meteorological forcing. Hydrol Earth Syst Sci 12:1007–1025Google Scholar
- Hulme M et al (2000) Using a climate scenario generator for vulnerability and adaptation assessments: MAGICC and SCENGEN version 2.4 workbook. Climatic Research UnitGoogle Scholar
- Meehl GA et al (2007a) Global climate projections. In: Solomon S et al (ed) Climate change 2007: the physical science basis. Cambridge University Press, Cambridge, pp 747–845Google Scholar
- Moss R et al (2008) Towards new scenarios for analysis of emissions, climate change, impacts, and response strategies. http://www.ipcc.ch/meetings/session28/doc8.pdf
- Nakicenovic N et al (2000) Special report on emissions scenarios, summary for policy makers. Intergovernmental panel on climate change. IPCC, SwitzerlandGoogle Scholar
- Santer BD, Wigley TML, Schlesinger ME, Mitchell JFB (1990) Developing climate scenarios from equilibrium GCM results. Max-Planck-Institut für Meteorologie, Report No 47Google Scholar
- Schlesinger ME et al (1997) Geographical scenarios of greenhouse-gas and anthropogenic-sulfate-aerosol induced climate changes. Report of the Climate Research Group, Department of Atmospheric Sciences, University of Illinois at Urbana-ChampaignGoogle Scholar
- Takahashi K, Matsuoka Y, Harasawa H (1998) Impacts of climate change on water resources, crop production and natural ecosystem in the Asia and Pacific region. J Global Environ Eng 4:91–103Google Scholar