1. CDC Cover

2. NOAA Lab roles in CCSP Strategic Plan for the U.S. Climate Change Science Program: Research Elements Element 3. Atmospheric Composition Aeronomy Laboratory (AL) Element 4. Climate Variability and Change Climate Diagnostics Center (CDC) Element 7. Carbon Cycle Climate Monitoring and Diagnostics Laboratory (CMDL) Element 10.Modeling Strategy Geophysical Fluid Dynamics Laboratory (GFDL) Final Report, July 2003

3. Advance national capabilities to identify the causes of climate variations. Provide credible information to enhance decision making. Assess climate predictability. Develop prediction tools based on state-of-the art methods. Develop new NOAA climate products and services. US Precip Since 1895 US Temps Since 1895 Purpose and Contribution to NOAA Mission The NOAA Climate Diagnostics Center provides a unique federal center of expertise for developing and applying climate diagnostic methods to improve understanding and predictions of climate. CDC research goals are to:

4. CDC research focuses especially on climate phenomena that have major impacts on society and the economy, including climate events such as major droughts and El Niño and La Niña conditions. Focus Drought in Great Plains, ca. 1935California floods during 1998 El Niño Focus

5. Example: Causes and Prediction of Drought Drought Causes,Prediction Fires in the West North Platte river, May 22, 2002 Mean flow: 1310 cu. ft/sec Observed flow: 0 cu. ft/sec.  Droughts are not simply climate phenomena; they have profound societal, economic, and environmental consequences.  Traditional federal/state response to drought has been reactive. We are moving toward a more proactive approach - “National Drought Preparedness Act of 2003”. Implications for NOAA wx/climate services -- Importance and context

6. The U.S. Drought and Heat 1998 - 2002 U.S. Drought 1998 - 2002

7. U.S. Oct-May Precipitation and Temperatures Average anomalies 1998-2002 Temperature Precipitation >+2°F <-10” <-5” Oct.-May P-T anomalies

8. An important clue: The 1998-2002 drought was part of a larger pattern. Drought causes - spatial patterns

9. Did unusual tropical ocean conditions force this pattern? The warming tropical “warm pool ” The strengthening El Niño Tropical ocean warming Role of tropical oceans

10. Observed and model simulated climate anomalies using observed sea surface temperatures Observed Temperature and Precipitation anomalies (June 1998 - May 2002) Model-simulated Temperature and Precipitation anomalies given observed SSTs for this period TempsPrecip.

11. U.S. surface temp trends Are trends in the ocean conditions also forcing longer-term temperature trends over the United States? Model simulations are using GFDL model with observed ocean temperature trends, but no CO 2 or aerosol trends.

12. Winter trend distributions Model-estimated probability distributions of U.S. regional temperature trends - ocean forcing only (constant CO 2 and aerosols) Western U.S. Eastern U.S. Obs.

13. Diagnostic interpretations The major factors contributing to the 1998-2002 drought were persistent La Niña conditions in the eastern tropical Pacific Ocean and a record warm Indian Ocean, the latter of which appears to be part of a longer-term trend. This was the “Perfect Ocean” for severe and sustained U.S. drought. Implication: Given foreknowledge of the tropical sea surface temperatures, the 1998-2002 drought and attendant warmth over large areas of the Northern Hemisphere, including parts of the U.S., would have been predictable. The recent trend in U.S. surface temperatures was also forced at least in part by trends in ocean conditions. More research will be required to assess natural vs. anthropogenic effects on the ocean trends, as well as contributions to the surface temperature trends from changing greenhouse gas forcing. The distributions, especially over the eastern U.S., provide a cautionary note that natural variability can still strongly affect multi-decadal trends. Diagnostic interpretations

14. Summary Climate diagnostic research is essential to achieving Goal 1 of the Climate Change Science Plan: “Improve knowledge of the Earth’s past and present climate and environment, including its natural variability, and improve understanding of of the causes of observed variability and change”. Extreme climate events such as drought have tremendous relevance to society and the economy. Improved climate information and forecasts will help to move us from a reactive toward a more proactive approach to such events. CDC research focuses on determining responses to climate forcings, especially at regional scales. Improving regional climate information is crucial to many decision-makers, especially in resource management. CDC works closely with the NOAA National Weather Service to improve current climate products and to develop and evaluate experimental products. Summary

15. Experimental Product: Rapid Response to Drought Create and regularly update summaries of current climate information and outlooks monthly Presentations at user meetings and distribution of summary sheets User focused research addressing questions related to current climate conditions

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