April 11-13, 2007

1. Climate Assessments Thomas Karl Climate Working Group Climate Observations & Analysis Program Review April 11-13, 2007 1

2. Outline • Climate Assessments - Overview • Recent and Ongoing Assessments • Climate Change Science Program (CCSP) • CCSP 1.1 – Temperature Trends in the Lower Atmosphere • CCSP 3.3 – Weather and Climate Extremes in a Changing Climate • International Panel on Climate Change (IPCC) • 2007 Release

3. OverviewClimate Assessment Scientific assessments of climate variability and change are critical in establishing the state of the science for policy makers and the general public • COA (& precursors) have partnered in producing major assessment reports: • Intergovernmental Panel on Climate Change (IPCC): 1990, 92, 95, 2001, 2007 • Climate Change Science Program (CCSP) 1.1 (2006), 3.3 (2008) • The U.S. National Assessment • Monthly, seasonal, and annual reports on the “State of the Climate”

4. Climate Change Science ProgramOverview • The CCSP Strategic Plan calls for the creation of 21 Synthesis and Assessment (SAP) reports organized around 5 Scientific Goals • COA involvement • Leading two SAPs: • 1.1Temperature Trends; 3.3 Weather and Climate Extremes • Participation in three SAPs • Paleoclimate, Climate Change &Transportation, Uncertainty • Providing Technical support for NOAA led SAPs Integrating federal research on global change and climate change • SAPs are intended to support informed discussion & decision-making by policy makers, resource managers, stakeholders, the media, & the general public • Abstracts & Executive Summary are accessible to High School graduate level understanding • Chapters are written to the complexity of Scientific American or similar magazines.

5. Climate Change Science ProgramAssessment 1.1 published in April 2006 • Objective – An understanding of: • Temperature changes in the atmosphere • Differences in these changes at various levels in the atmosphere • The causes of these changes & differences • Key Highlights: • Global-average warming in the atmosphere now similar to warming observed at the surface • Fundamental change from earlier findings (US-NRC and IPCC reports) • Findings also consistent with results obtained from models (though discrepancies remain in the tropics) • Increased confidence in understanding of observed climate change/causes and increased confidence in climate model results

6. CCSP 3.3 - Weather & Climate ExtremesMotivation • IPCC assessments evaluated weather & climate extreme on a global basis • Considered both observed and projected changes in climate. • A gradually warming world will be accompanied by changes in the variability and frequency of weather and climate extremes. • BUT… • No specific IPCC assessment on weather & climate extremes across N.A., Hawaii, and U.S. territories • AND… • N.A observing systems are among the best in the world • N.A. weather & climate extremes are some of the most notable occurring across the globe. U.S. experienced 70 weather/climate disasters from 1980-2006 that were > $1 billion

7. CCSP 3.3 - Weather & Climate ExtremesOverview of Report • Objective: – An understanding of: • Changes in weather and climate extremes as related to their intensity or frequency, and likely future evolution • Weather extremes: Unusual in their occurrence or have destructive potential, such as torrential rainfall, hurricanes, severe winter storms, heat waves, etc. • Climate extremes: Represent the same events, as above but viewed over many seasons, decades, or longer • Regions of Focus: • North America • Caribbean • Hawaii and U.S. Pacific islands To be published June 2008

8. CCSP 3.3 Chapter Titles and Authors • Preface --- T. Karl, C. Miller, W. Murray • Executive Summary --- CLA: T. Karl & J. MeehlLAs: T. Peterson, K. Kunkel, W. Gutowski, D. Easterling Scientific Ed: S. Hassol, C. Miller, W. Murray • Chapter 1 --- Why weather and climate extremes matter CLAs: T. PetersonLAs: D. Anderson, S. Cohen, M. Cortez, R. Murnane, C. Parmesan, D. Phillips, R. Pulwarty, J. Stone • Chapter 2 --- Observed Changes of Weather and Climate Extremes CLA: K. KunkelLAs: P. Bromirski, H. Brooks, T. Cavazos, A. Douglas, D. Easterling, K. Emanuel, P. Groisman, G. Holland, T. Knutson, P. Komar, D. Levinson, T. Peterson, R. Smith • Chapter 3 --- How well do we understand the causes of observed changes in extremes, and what are the projected future changes? CLA: W. Gutowski, Jr.LAs: G. Hegerl, .G.. Holland, T. Knutson, L. Mearns, R.  Stouffer, P. Webster, F. Zwiers, T. Peterson • Chapter 4 --- Recommendations for Improving our Understanding CLA: D. EasterlingLAs: D. Anderson, W. Gutowski, Jr., K. Kunkel, T. Peterson • Glossary --- A. Waple • Graphics, Ass’t Scientific Ed., & Tech. Ed. S. Veasey, A. Waple, A. Markel.

9. CCSP 3.3 Milestones Remaining SAP milestones beginning in 2007 • Draft Synthesis Product submitted to NRC for review – Feb 07 • Receive NRC comments – Jun 07 • FACA meeting (Aspen) – Jun 07 • Revised SAP 3.3 posted for Public comments – Aug 07 • Public comments received – Oct 07 • Revised SAP 3.3 submitted to CCSP principals (interagency) – Dec 07 • SAP 3.3 submitted to NSTC - Jan 08 • SAP 3.3 posted to web site (with response to all comments) Mar 08 • SAP 3.3 printed version availableJun 08

10. Intergovernmental Panel on Climate Change2007 Assessment COA Funded Authors • Chapter 1 --- Historical Overview of Climate Change Science LA: T. Peterson CAs: M. Allen*, G. Hegerl*, B. Santer*, K. Taylor*, K. Trenberth* Chapter 3 --- Observations: Surface and Atmospheric Climate Change LAs: D. Easterling, B. Soden* CAs: B. Gleason, J. Lawrimore, D. Levinson, R. Vose D. Wuertz, J. Christy*, A. Dai*, M. Free*, P. Groisman*, K. Kunkel*, J. Lanzante*, C. Mears*, E. Chang*, M. Free, K. Rosenlof, S. Sherwood* Review Ed.: T. Karl • Chapter 4 --- Observations: Changes in Snow, Ice, and Frozen Ground CA: D. Robinson* • Chapter 5 --- Observations: Oceanic Climate Change and Sea Level LA: S. Levitus CA: R. Feely* • Chapter 6 ---- Paleoclimate CAs: E. Cook*, H. Pollack*, J. Overpeck*, J. Cole*, L. Stott*, L. Thompson** *non NOAA

11. Questions

12. CCSP Scientific Goals • Goal 1:Improve knowledge of the Earth's past and present climate and environment, including its natural variability, and improve understanding of the causes of observed variability and change.(3 Synthesis & Assessment Products) • Goal 2:Improve quantification of the forces bringing about changes in the Earth's climate and related systems. (4 Synthesis & Assessment Products) • Goal 3:Reduce uncertainty in projections of how the Earth's climate and related systems may change in the future.(4 Synthesis & Assessment Products) • Goal 4:Understand the sensitivity and adaptability of different natural and managed ecosystems and human systems to climate and related global changes. (7 Synthesis & Assessment Products) • Goal 5:Explore the uses and identify the limits of evolving knowledge to manage risks and opportunities related to climate variability and change. (3 Synthesis & Assessment Products)

13. Technical support for all CCSP reportsNCDC to produce eight NOAA-led CCSP Reports • COA is providing graphics, editing, layout, and printing for all NOAA-led CCSP reports. • Contract team formed in November 2006