1. Observing Climate Variability and Change Thomas R. Karl National Oceanic and Atmospheric Administration National Environmental Satellite Data and Information Service National Climatic Data Center Asheville, NC 28801-5001, USA

2. PHYSICALPHYSICAL PROCESSPROCESS BIOLOGICAL PROCESSES CLIMATE CHANGE FORCINGS } $ IMPACTS CROPCROP FOREST MIGRATION YIELDYIELD COASTALCOASTAL HABITATHABITAT $ 1) How has the climate changed or varied? 2) How well do we understand the climate system ? 3) What are the causes of climate change and variability? 4) How can we characterize the impacts of climate change? }

5. How significant are the uncertainties? State and Forcings Variables  Few have quantitative confidence intervals (CIs) (including time- dependent biases) e.g., global surface temperature, CO 2  Most CIs do not include time-dependent biases  For many, CIs are uncertain or unknown Why?  Adhering to climate observing principles and guidelines still does not have a high priority Smoothed annual anomalies of global combined land-surface air and sea surface temperatures ( o C).

6. Adoption of ten principles for climate monitoring More comprehensive global observations --- Prioritization concept Improved global telecommunications Better use of data… more products Critical need for system monitoring and oversight responsibility --- Examples The Climate Observing System: What is needed?

7. Adherence to Ten Principles for both space- and surface-based observations 1. Management of Network Change 2. Parallel Testing 3. Metadata 4. Data Quality and Continuity 5. Environmental Assessments The international framework for sharing data is vital. 6. Historical Significance 7. Complementary Data 8. Climate Requirements 9. Continuity of Purpose 10. Data and Metadata Access

8. Definition of Terms Time to Pay-Off – the time required for an impact to be realized, i.e., upgrading an existing system or implementing a new system Feasibility – readiness to implement the observing system considering technical aspects and resource requirements Impact – potential for reducing uncertainties

9. A Global Network of Reference Quality Radiosonde Sites Example: Demonstrating Prioritization Concept

10. Temperature Indicators “Climate Impacts”

11. Temperature Indicators “Climate Understanding”

12. Hydrological Indicators “Climate Impacts”

13. Hydrologic Indicators “Climate Understanding”

14. What are the causes of climate change and variability

15. The Climate Observing System: What is needed? Observing Systems Oversight and System Monitoring Capability Establish climate requirements for observing systems (atmosphere, ocean, terrestrial, cryosphere), such as weather services do today  Includes instruments on satellites  Spatial and temporal sampling, etc.  Reprocessing and reanalysis Tracks the performance of the observations, the gathering of the data, and the processing systems Resources and influence to fix problems

16. Real-time Network Performance Monitoring U.S. Climate Reference Network

19. Five different research teams using independent methods to identify time- dependent biases in the tropospheric temperature records Teams: NOAA– GFDL – NCDC Univ. of Alabama UK Meteorological Office Texas A & M University) Observing and Data System Deficiencies Courtesy: Free et al (in review BAMS) Percent of Teams Identifying Biases

20. Adoption of ten principles for climate monitoring More comprehensive global observations Improved global telecommunications Better use of data… more products Critical need for system monitoring and oversight responsibility The Climate Observing System: What is needed?

21. Some Variables are Effectively Monitored for Trend Scripps Institute of Oceanography NOAA

22. Impact of Satellite Orbital Drift  Will be fixed on US NPOESS (2009) Ascending minus descending temperatures MSU2 JJA 1989-91 from NOAA 11 Observing and Data System Deficiencies Diurnal corrections required for each satellite. Changes in orbits and equator crossing times of satellites are aliased onto the diurnal cycle, requiring corrections MSU channel 2 temperatures over land, from Wentz (black lower) and Christy-Spencer (red lower) and difference (top).

23. Effect of Calibration Target Correction on MSU Channel 2 Observing and Data System Deficiencies Courtesy F. Wentz