| 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 |