Biological and Environmental Research - Earth and Environmental System Sciences
Earth and Environmental System Modeling

Human influence on the seasonal cycle of tropospheric temperature

TitleHuman influence on the seasonal cycle of tropospheric temperature
Publication TypeJournal Article
Year of Publication2018
JournalScience
Volume361
Number6399
Pageseaas8806
Abstract / Summary

We provide scientific evidence that a human-caused signal in the seasonal cycle of tropospheric temperature has emerged from the background noise of natural variability. Satellite data and the anthropogenic “fingerprint” predicted by climate models show common large-scale changes in geographical patterns of seasonal cycle amplitude. These common features include increases in amplitude at mid-latitudes in both hemispheres, amplitude decreases at high latitudes in the Southern Hemisphere, and small changes in the tropics. Simple physical mechanisms explain these features. The model fingerprint of seasonal cycle changes is identifiable with high statistical confidence in five out of six satellite temperature datasets. Our results suggest that attribution studies with the changing seasonal cycle provide powerful evidence for a significant human effect on Earth’s climate.

URLhttp://dx.doi.org/10.1126/science.aas8806
DOI10.1126/science.aas8806
Journal: Science
Year of Publication: 2018
Volume: 361
Number: 6399
Pages: eaas8806
Publication Date: 07/2018

We provide scientific evidence that a human-caused signal in the seasonal cycle of tropospheric temperature has emerged from the background noise of natural variability. Satellite data and the anthropogenic “fingerprint” predicted by climate models show common large-scale changes in geographical patterns of seasonal cycle amplitude. These common features include increases in amplitude at mid-latitudes in both hemispheres, amplitude decreases at high latitudes in the Southern Hemisphere, and small changes in the tropics. Simple physical mechanisms explain these features. The model fingerprint of seasonal cycle changes is identifiable with high statistical confidence in five out of six satellite temperature datasets. Our results suggest that attribution studies with the changing seasonal cycle provide powerful evidence for a significant human effect on Earth’s climate.

DOI: 10.1126/science.aas8806
Citation:
Santer, B, S Po-Chedley, M Zelinka, I Cvijanovic, C Bonfils, P Durack, Q Fu, et al.  2018.  "Human influence on the seasonal cycle of tropospheric temperature."  Science 361(6399): eaas8806.  https://doi.org/10.1126/science.aas8806.