Climatic Change

, Volume 62, Issue 1–3, pp 75–113 | Cite as

Mid-Century Ensemble Regional Climate Change Scenarios for the Western United States

  • L. Ruby Leung
  • Yun Qian
  • Xindi Bian
  • Warren M. Washington
  • Jongil Han
  • John O. Roads

Abstract

To study the impacts of climate change on water resources in the western U.S., global climate simulations were produced using the National Center for Atmospheric Research/Department of Energy (NCAR/DOE) Parallel Climate Model (PCM). The Penn State/NCAR Mesoscale Model (MM5) was used to downscale the PCM control (20 years) and three future(2040–2060) climate simulations to yield ensemble regional climate simulations at 40 km spatial resolution for the western U.S. This paper describes the regional simulations and focuses on the hydroclimate conditions in the Columbia River Basin (CRB) and Sacramento-San Joaquin River (SSJ) Basin. Results based on global and regional simulations show that by mid-century, the average regional warming of 1 to 2.5 °C strongly affects snowpack in the western U.S. Along coastal mountains, reduction in annual snowpack was about70% as indicated by the regional simulations. Besides changes in mean temperature, precipitation, and snowpack, cold season extreme daily precipitation increased by 5 to 15 mm/day (15–20%) along theCascades and the Sierra. The warming resulted in increased rainfall at the expense of reduced snowfall, and reduced snow accumulation (or earlier snowmelt) during the cold season. In the CRB, these changes were accompanied by more frequent rain-on-snow events. Overall, they induced higher likelihood of wintertime flooding and reduced runoff and soil moisture in the summer. Changes in surface water and energy budgets in the CRB and SSJ basin were affected mainly by changes in surface temperature, which were statistically significant at the 0.95 confidence level. Changes in precipitation, while spatially incoherent, were not statistically significant except for the drying trend during summer. Because snow and runoff are highly sensitive tospatial distributions of temperature and precipitation, this study shows that (1) downscaling provides more realistic estimates of hydrologic impacts in mountainous regions such as the western U.S., and (2) despite relatively small changes in temperature and precipitation, changes in snowpack and runoff can be much larger on monthly to seasonal time scales because the effects of temperature and precipitation are integrated over time and space through various surface hydrological and land-atmosphere feedback processes. Although the results reported in this study were derived from an ensemble of regional climate simulations driven by a global climate model that displays low climate sensitivity compared with most other models, climate change was found to significantly affect water resources in the western U.S. by the mid twenty-first century.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Barnett, T. P., Pierce, D. W., and Schnur, R.: 2001, ‘Detection of Anthropogenic Climate Change in the World's Oceans’, Science 292, 270–274.Google Scholar
  2. Cayan, D. R., Redmond, K. T., and Riddle, L. G.: 1999, ‘ENSO and Hydrologic Extremes in the Western United States’, J. Climate 12, 2881–2893.Google Scholar
  3. Cubasch, U., Meehl, G. A., Boer, G. J., Stouffer, R. J., Dix, M., Noda, A., Senior, C. A., Raper, S., and Yap, K. S.: 2001, ‘Projections of Future Climate Change’, Chapter 9, Climate Change 2001: The Scientific Basis. Intergovernmental Panel on Climate Change, Cambridge University Press, 881 pp.Google Scholar
  4. Dai, A., Meehl, G. A., Washington, W. M., Wigley, T. M. L., and Arblaster, J. A.: 2001a, ‘Ensemble Simulation of 21st Century Climate Changes: Business as Usual vs. CO2 Stabilization’, Bull. Amer. Meteorol. Soc. 82, 2377–2388.Google Scholar
  5. Dai, A., Washington, W. M., Meehl, G. A., Bettge, T. W., and Strand, W. G.: 2004, ‘The ACPI Climate Change Simulations’, Clim. Change 62, 29–43.Google Scholar
  6. Dai, A., Wigley, T. M. L., Boville, B. A., Kiehl, J. T., and Buja, L. E.: 2001b, ‘Climates of the 20th and 21st Centuries Simulated by the NCAR Climate System Model’, J. Climate 14, 485–519.Google Scholar
  7. Daly, C., Neilson, R.P., and Phillips, D. L.: 1994, ‘A Statistical-Topographic Model for Mapping Climatological Precipitation over Mountainous Terrain’, J. Appl. Meteorol. 33, 140–158.Google Scholar
  8. Department of Energy: 1998, ACPI: The Accelerated Climate Prediction Initiative, Pacific Northwest National Laboratory, Department of Energy, Germantown, MD, 30 pp.Google Scholar
  9. Dickinson, R. E., Kennedy, P. J., Henderson-Sellers, A., and Wilson, M.: 1986, ‘Biosphere-Atmosphere Transfer Scheme (BATS) for the NCAR Community Climate Model’, NCAR Tech. Note, NCAR/TN-275+STR, Natl. Cent. for Atmos. Res., Boulder, CO.Google Scholar
  10. Gershunov, A. and Barnett, T. P.: 1998, ‘ENSO Influence on Intraseasonal Extreme Rainfall and Temperature Frequencies in the Contiguous United States: Observations and Model Results’, J. Climate 11, 1575–1586.Google Scholar
  11. Giorgi, F., Hewitson, B., Christensen, J., Hulme, M., Von Storch, H., Whetton, P., Jones, R., Mearns, L., and Fu, C.: 2001, ‘Regional Climate Information-Evaluation and Projections’, Climate Change 2001: The Scientific Basis. Intergovernmental Panel on Climate Change, Cambridge University Press, 881 pp.Google Scholar
  12. Giorgi, F., Hurrell, J. W., Marinucci, M. R., and Beniston, M.: 1997, ‘Elevation Dependency of the Surface Climate Signal: A Model Study’, J. Climate 10, 288–296.Google Scholar
  13. Giorgi, F., Mearns, L. O., Shields, C., and McDaniel, L.: 1998, ‘Regional Nested Model Simulations of Present Day and 2 x CO2 Climate over the Central Plains of the U.S.’, Clim. Change 40, 457–493.Google Scholar
  14. Grell, G., Dudhia, J., and Stauffer, D. R.: 1993, ‘A Description of the Fifth Generation Penn State/NCAR Mesoscale Model (MM5)’, NCAR Tech. Note., NCAR/TN-398+IA, Nat. Cent. for Atmos. Res., Boulder, CO.Google Scholar
  15. Hamlet, A. F. and Lettenmaier, D. P.: 1999, ‘Effects of Climate Change on Hydrology and Water Resources in the Columbia River Basin’, Am. Water Res. Assoc. 35(6), 1597–1623.Google Scholar
  16. Hong, S.-Y. and Leetmaa, A.: 1999, ‘An Evaluation of the NCEP RSM for Regional Climate Modeling’, J. Climate 12, 592–609.Google Scholar
  17. IPCC: 2001, Climate Change 2001–The Scientific Basis, Cambridge University Press, 881 pp.Google Scholar
  18. Jones, R. G., Murphy, J. M., Noguer, M., and Keen, A. B.,: 1997, ‘Simulation of Climate Change over Europe Using a Nested Regional Climate Model. II: Comparison of Driving and Regional Model Responses to a Doubling of Carbon Dioxide’, Quart. J. Roy. Meteorol. Soc. 123, 265–292.Google Scholar
  19. Juang, H.-M. and Kanamitsu, M.: 1994: ‘The NMC Nested Regional Spectral Model’, Mon. Wea. Rev. 122, 3–26.Google Scholar
  20. Kim, J.: 2001, ‘A Nested Modeling Study of Elevation-Dependent Climate Change Signals in California Induced by Increased Atmospheric CO2’, Geophys. Res. Lett. 28(15), 2951.Google Scholar
  21. Laprise R., Caya, D., Giguère, M., Bergeron, G., Côte, H., Blanchet, J.-P., Boer, G. J., and McFarlane, N. A.: 1998, ‘Climate and Climate Change in Western Canada as Simulated by the Canadian Regional Climate Model’, Atmosphere-Ocean 36, 119–167.Google Scholar
  22. Leung, L. R. and Ghan, S.: 1999a, ‘Pacific Northwest Climate Sensitivity Simulated by a Regional Climate Model Driven by a GCM. Part I: Control Simulations’, J. Climate 12, 2010–2030.Google Scholar
  23. Leung, L. R. and Ghan, S.: 1999b, ‘Pacific Northwest Climate Sensitivity Simulated by a Regional Climate Model Driven by a GCM. Part II: 2 x CO2 Simulations’, J. Climate 12, 2031–2053.Google Scholar
  24. Leung, L. R., Qian, Y., and Bian, X.: 2003a, ‘Hydroclimate of the Western United States Based on Observations and Regional Climate Simulation of 1981-2000. Part I: Seasonal Statistics’, J. Climate 16(12), 1892–1911.Google Scholar
  25. Leung, L. R., Qian, Y., and Bian, X., and Hunt, A.: 2003b, ‘Hydroclimate of the Western United States Based on Observations and Regional Climate Simulation of 1981-2000. Part II: Mesoscale ENSO Anomalies’, J. Climate 16(12), 1912–1928.Google Scholar
  26. Leung, L. R., Qian, Y., Han, J., and Roads, J. O.: 2003c, ‘Intercomparison of Global Reanalyses and Regional Simulations of Cold Season Water Budgets in the Western U.S.’, J. Hydrometeorology, in press.Google Scholar
  27. Leung, L. R. and Wigmosta, M. S.: 1999, ‘Potential Climate Change Impacts on Mountain Watersheds in the Pacific Northwest’, J. Amer. Water Resour. Assoc. 35(6), 1463–1471.Google Scholar
  28. Mantua, N. J., Hare, S. R., Zhang, U., Wallace, J. M., and Francis, R. C.: 1997, ‘A Pacific Interdecadal Climate Oscillation with Impacts on Salmon Production’, Bull. Amer. Meteorol. Soc. 78, 1069–1079.Google Scholar
  29. Maurer, E. P., O’Donnell, G. M., Lettenmaier, D. P., and Roads, J. O.: 2001, ‘Evaluation of the Land Surface Water Budget in NCEP/NCAR and NCEP/DOE Reanalyses Using an Off-Line Hydrologic Model’, J. Geophys. Res. 106, 17841–17862.Google Scholar
  30. Miller, N. L., Gutowski, W. J., Kim, J., and Strem, E.: 2002, ‘Assessing California Streamflow for Present Day and 2040 to 2049 Climate Scenarios’, J. Hydrometeorology, in press.Google Scholar
  31. Mote, P., Canning, D., Fluharty, D., Francis, R., Franklin, J., Hamlet, A., Hershman, M., Holmberg, M., Gray-Ideker, K., Keeton, W. S., Lettenmaier, D., Leung, R., Mantua, N., Miles, E., Noble, B., Parandvash, H., Peterson, D.W., Snover, A., and Willard, S.: 1999, Impacts of Climate Variability and Change, Pacific Northwest, National Atmospheric and Oceanic Administration, Office of Global Programs, and JISAO/SMA Climate Impacts Group, Seattle, WA, 110 pp.Google Scholar
  32. National Assessment Report: 2000, Water: The Potential Consequences of Climate Variability and Change for the Water Resources of the United States, a Report of the NationalWater Assessment Group for the U.S. Global Change Research Program, 151 pp.Google Scholar
  33. Pierce, D.W., Barnett, T. P., Tokmakian, R., Semtner, A., Maltrud, M., Lysne, J., and Craig, A.: 2004, ‘The ACPI Project, Element 1: Initializing a Coupled Climate Model from Observed Conditions’, Clim. Change 62, 13–28.Google Scholar
  34. Roads, J. O. and Chen, S.-C.: 2000, ‘Surface Water and Energy Budgets in the NCEP Regional Spectral Model’, JGR-Atmospheres 105, 29539–29550.Google Scholar
  35. Roads, J. O., Chen, S.-C., and Kanamitsu, M.: 2002, ‘U.S. Regional Climate Simulations and Seasonal Forecasts’ J. Geophys. Res., accepted.Google Scholar
  36. Washington, W. M., Weatherly, J. W., Meehl, G. A., Semtner, A. J., Bettge, T.W., Craig, A. P., Strand, W. G. Jr., Arblaster, J., Wayland, V. B., James, R., and Zhang, Y.: 2000, ‘Parallel Climate Model (PCM) Control and Transient Simulations’, Clim. Dyn. 16, 755–774.Google Scholar
  37. Whetton P. H., Katzfey, J. J., Hennesey, K. J., Wu, X., McGregor, J. L., and Nguyen, K.: 2001, ‘Using Regional Climate Models to Develop Fine Resolution Scenarios of Climate Change: An Example for Victoria, Australia’, Clim. Res. 16, 181–201.Google Scholar

Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • L. Ruby Leung
    • 1
  • Yun Qian
    • 1
  • Xindi Bian
    • 1
  • Warren M. Washington
    • 2
  • Jongil Han
    • 3
  • John O. Roads
    • 3
  1. 1.Pacific Northwest National LaboratoryRichlandU.S.A.
  2. 2.National Center for Atmospheric ResearchBoulderU.S.A
  3. 3.Scripps Institution of OceanographyLa JollaU.S.A

Personalised recommendations