Detection and Attribution of Climate Change |
Why is detection and attribution work important? |
Structure of talk |
Introduction: Definition of ÒconsensusÓ |
Introduction: Do the IPCC AR4 findings constitute a ÒconsensusÓ of climate science experts? |
Structure of talk |
Where do you believe a consensus has formed? |
ÒUnequivocalÓ warming of the climate system |
Where do you believe a consensus has formed? |
The scientific evidence for a human ÒfingerprintÓ on global climate has strengthened over time |
Natural factors alone cannot explain the recent warming of the EarthÕs surface |
What is Òclimate fingerprintingÓ? |
Human-caused fingerprints have been identified in many different aspects of the climate system |
We have made considerable progress in defining the ÒfingerprintsÓ of different forcings |
Fingerprint detection explained pictoriallyÉ. |
Estimating the ÒnoiseÓ of natural internal variability |
Optimal fingerprinting: A brief example |
D&A in a Òmulti-modelÓ framework: Use of multiple models to estimate fingerprints and noise |
Estimating signal-to-noise ratios and Òdetection timesÓ |
Estimating signal-to-noise ratios and Òdetection timesÓ |
For water vapor, there is no evidence that Òclimate noiseÓ is systematically underestimated in IPCC AR4 models |
Structure of talk |
Where can consensus be expected in the near future? |
Structure of talk |
Where can statistical science provide further assistance to future D&A research? |
Future research I: Sensitivity of D&A results to Òmodel qualityÓ |
Future research I: Sensitivity of D&A results to Òmodel qualityÓ |
Future research II: Improvement of observational datasets with sparse, space- and time-varying coverage |
Future research II: The ocean observing network has changed dramatically over time |
Future research II: Do models systematically underestimate ÒobservedÓ ocean temperature variability? |
Future research II: Sampling model data at locations of ocean observations improves model-data agreement |
Future research II: Implications of observational uncertainty for D&A research |
Conclusions |
A brief history of D&A research: Some important milestones |