Observations and Trends
Global
"Eleven of the last twelve years (1995-2006) rank among the twelve warmest years in the instrumental record of global surface temperature (since 1850). The 100-year linear trend (1906-2005) of 0.74 [0.56 to 0.92]°C1 is larger than the corresponding trend of 0.6 [0.4 to 0.8]°C (1901-2000) given in the Third Assessment Report (TAR). The temperature increase is widespread over the globe and is greater at higher northern latitudes. Land regions have warmed faster than the oceans ." Intergovernmental Panel on Climate Change (IPCC), Fourth Assessment Report, Synthesis Report, Summary for Policy Makers (AR4), 2007.
IPCC AR4 Working Group 1( Physical Sciences of Climate Change)
Summary for Policy Makers
Full Report
WWA Guide to IPCC
Global Temperature Trends, Goddard Institute for Space Studies, NASA
Global Temperature Change and Temperature Anomalies, NASA
Trend in global average surface temperature, United Nations Environmental Programme (UNEP)
NOAA/NESDIS/NCDC Temperature Trends: Is the Climate Warming?
Climate of 2007, NCDC, Climate Monitoring Division
Climate change Observations and predictions, Hadley Centre
Northern Hemisphere and Continental US
US Precipitation and Temperature Trends, Imke Durre, NOAA, Climate Diagnostics and Predication Workshop, 2006
Annual temperature range time-series trends and long-range forecasting, Mary Snow, National Weather Digest, December 2005
Recent Northern Hemisphere snow cover extent trends and implications for the snow-albedo feedback, Stephen J. Déry,
Ross D. Brown, Geophysical Research Letters, 2007
Trends and Variability of Snowfall and Snow Cover Across North America and Eurasia. Part 1: Data Quality and Homogeneity Analysis, Richard R. Heim Jr., David A. Robinson, 2006
Variability and trends in the annual snow-cover cycle in Northern Hemisphere land areas, 1972–2000, Dennis G. Dye, Hydrol. Process., 2002.
Northern Hemispheric Snow Cover and Extent, NSIDC
Snow Glossary
Western US
Climatic and Hydrologic Trends in the Western U.S.: A Review of Recent Peer-Reviewed Research, Intermountain West Climate Summary, January 2007, By Brad Udall, WWA and Gary Bates, NOAA/ESRL/PSD
Climate Change: What do we know & What Don't we Know?, Klaus Wolter, NOAA-ESRL, WWA
Climate Change Impacts on the United States: The Potential Consequences of Climate Variability and Change, 2003
National Assessment Synthesis Team, US Climate Change Science Program: (www.climatescience.gov), US Global Change Research Program: (www.usgcrp.gov)
Relevant Chapters:
Chapter 8: Potential Consequences of Climate Variability & Change for the Western United States
Chapter 7: Potential Consequences of Climate Variability & Change for the Great Plains
Chapter 14: Potential Consequences of Climate Variability & Change for the Water Resources of the United States
Water Sector research
Western Region research
Colorado Temperature Trends, Klaus Wolter, NOAA-ESRL, WWA
Declining mountain snowpack in western North America. (2005). Mote, P. W., A. F. Hamlet, M. Clark, and D. P. Lettenmaier Bulletin of the American Meteorological Society 86(1):39-49.
Cover story of the Jaunary 2005 edition of the Bulletin of the American Meteorological Society. This research shows that while there has been a decline in snowpack in the Pacific Northwest, there is not a similar signal in the Colorado River Basin.
Seasonal Cycle Shifts in Hydroclimatology over the Western United States. (2004). Regonda, Satish K. and Balaji Rajagopalan, Journal of Climate, 18:372-384.
This article is similar to the Mote et. al. article above. The researchers found that there is a strong trend of earlier peak streamflows in the Pacific Northwest due to higher temperatures during March and April.
Covariability of Spring Snowpack and Summer Rainfall across the Southwest United States
David S. Gutzler
Journal of Climate, Volume 12, pp. 4018-4027, 2000.
The Impacts of Climatic Changes for Water Resources of the Colorado and Sacramento-San Joaquin River Basins.
Peter H. Gleick and Elizabeth L. Chalecki
Journal of the American Water Resources Association, OL. 35, NO. 6, December 1999.
Changes in Streamflow Timing in the Western United States in Recent Decades, USGS Fact Sheet, March 2005
Pilot Study on snowmelt timing in the Colorado Rocky Mountains: Changes in Streamflow, USGS
Trends and Variability in Snowmelt Runoff in the Western United States, Gregory J. McCabe, U.S. Geological Survey, Denver, Colorado, Martyn Clark, University of Colorado, Boulder, Colorado, J. of Hydrometeorology, 2005
Trends in Snowfall versus Rainfall in the Western United States, Noah Knowles, Michael D. Dettinger, Daniel R. Cayan, Journal of Climate, 2005
Warming and Earlier Spring Increase Western U.S. Forest Wildfire Activity, Science, A. L. Westerling, H. G. Hidalgo, D. R. Cayan, T. W. Swetnam , August 2006
What Climatic Forcing Control Observed Changes in Runoff-Timing across Western North America? Iris Stewart, Dan Cayan, Mike Dettinger
Variability and Trends in Mountain Snowpack in Western North America, Philip W. Mote, Martyn Clark, and Alan F. Hamlet
Precipitation Trends in the Southwest United States, Atmoz.org, 2007
Precipitation and Temperature Trends in Tucson, Arizona, Atmoz.org, 2007
Changes toward Earlier Streamflow Timing across Western North America, Iris Stewart, Dan Cayan, Mike Dettinger, J. of Climate, 2004
Rain-on-Snow Events in the Western United States, Gregory McCabe, Martyn Clark, Lauren Hay, BAMS, September 2006
Western water resources in a changing climate, Testimony before the U.S. Senate Committee on Energy and Natural
Resources, Subcommittee on Water and Power, Philip W. Mote, Ph.D. Climate Impacts Group, University of Washington, Seattle, June 6, 2007
Projections
Projection: The term "projection" is used in two senses in the climate change literature. In general usage, a projection can be regarded as any description of the future and the pathway leading to it. However, a more specific interpretation has been attached to the term "climate projection" by the IPCC when referring to model-derived estimates of future climate. Source: IPCC
Scenario: A scenario is a coherent, internally consistent and plausible description of a possible future state of the world. It is not a forecast; rather, each scenario is one alternative image of how the future can unfold. A projection may serve as the raw material for a scenario, but scenarios often require additional information (e.g., about baseline conditions). A set of scenarios is often adopted to reflect, as well as possible, the range of uncertainty in projections. Other terms that have been used as synonyms for scenario are "characterization", "storyline" and "construction". Source: IPCC
Scenario Family: One or more scenarios that have the same demographic, politico-societal, economic and technological storyline. Source: IPCC
Intro to Climate Modeling, Stanford University
Intro to Climate Scenarios, Stanford University
IPCC AR4 Report, (2007) Chapter 10: Global Climate Projections
IPCC AR4 Report, (2007) Chapter 11: Regional Climate Projections
Model projections of an imminent transition to a more arid climate in southwestern North America
Richard Seager, Mingfang Ting, Isaac Held, Yochanan Kushnir, Jian Lu, Gabriel Vecchi, Huei-Ping Huang, Nili Harnik, Ants Leetmaa, Ngar-Cheung Lau, Cuihua Li, Jennifer Velez, and Naomi Naik Published online April 9 2007; 10.1126/science.1139601 (Science Express Reports)
Colorado River Basin Climate: What Lies Ahead?, Brad Udall, 2007 Regional Water Symposium, Tucson, Arizona, August 31, 2007
Climate Change: An Information Statement of the American Meteorological Society
(Adopted by AMS Council on 1 February 2007) Bull. Amer. Met. Soc., 88
Investigating Climate Change of Western North America, USGS Fact Sheet, 2003
Climate of 2007: Annual Review, NCDC
Global Review
US Summary
US Drought
WWA Activities
Colorado River Climate Change Webpage
Past Peak Water in the Southwest, Hoerling and Eischeid, submitted to Southwest Hydrology
Outlook for Water in the West at 2050 PPT (PDF format), Hoerling
A multi model ensemble approach to assessment of climate change impacts on hydrology and water resources of the colorado river basin, Christensen and Lettenmaier, submitted.
Colorado Temperature Trends, Wolter PPT (PDF)
Quality Assessment of Colorado's Long-term Temperature Data, Doesken PPT (PDF)
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