Identifying Human Influences on Atmospheric Temperature
Objective
- Performs the first multi-model fingerprint study with CMIP-5 simulation output and satellite measurements of stratospheric and tropospheric temperature change
Main scientific points
- Clearest evidence to date of a human influence on atmospheric temperature
- Satellite data and CMIP-5 simulations of historical climate change show similar geographical patterns of tropospheric warming and lower stratospheric cooling
- Sustained, global-scale tropospheric warming and stratospheric cooling cannot be explained by natural internal climate variability
- Shows that the identification of a human-caused signal in atmospheric temperature is robust to uncertainties in models and data
- Maintains DOE’s leadership in fingerprint research
We find some of the clearest evidence to date of a discernible human influence on atmospheric temperature. Satellite data and computer model simulations of historical climate change show common patterns of pronounced warming of the troposphere and cooling of the lower stratosphere. In the model simulations, these changes are mainly caused by human factors. We show that sustained, global-scale tropospheric warming and lower stratospheric cooling cannot be explained by natural climate variability. Our results are robust to current uncertainties in models and satellite observations.