Department of Water Resources Home

Flood Management

California State Climatologist

3310 El Camino Avenue
Suite 200
Sacramento, CA 95821

Mailing Address:
P.O. Box 219000
Sacramento, CA 95821-9000

Climate Change

Earth's climate is a dynamic system that includes many past periods of warming and cooling. Observations over the past century have shown an increase in atmospheric temperatures. In addition, atmospheric concentrations of carbon dioxide and other so-called greenhouse gases are increasing. Research is currently in progress to determine what future changes in climate will occur based on different scenarios of increasing greenhouse gas concentrations in the atmosphere. Other research is being conducted to identify and assess the impacts of the expected climate change. Many California state agencies and universities are involved in this research. Information on California and climate change work can be found at

In June of 2005, Governor Arnold Schwarzenegger issued Executive Order, # S-3-05 acknowledging the potential impacts of climate change on California. The executive order sets targets for greenhouse gas emissions reductions in the state, directs the formation of a Climate Action Team led by the California Environmental Protection Agency, and sets up a biannual reporting schedule for state agencies to identify impacts and potential mitigation plans. The first of these Climate Action Team reports was due in early 2006. Copies of the report are available at the web site listed above.

In addition, the California Department of Water Resources (DWR) and the U. S. Bureau of Reclamation (USBR) have put together a work team to investigate water resources related issues of climate change. In response to the governor's executive order, the work team has putting out a report that deals with climate change and water resources for the state of California as a companion report to the 2006 Climate Action Team report. Work continues towards generating a probabilistic risk assessment framework for impact assessments and evaluation of mitigation strategies. The Department of Water Resources has also created a climate change matrix team to coordinate climate change activities among its various divisions.