Our various graphics and model-observation comparisons have been updated with 2025 data. There are a few version updates that make some difference (particularly in sea ice extent), but the basic story is similar to last year. Feel free to comment and/or suggest changes for the future, including potential new comparisons.
SSU
Not just another dot on the graph? Part II
Annual updates to the model-observation comparisons for 2023 are now complete. The comparisons encompass surface air temperatures, mid-troposphere temperatures (global and tropical, and ‘corrected’), sea surface temperatures, and stratospheric temperatures. In almost every case, the addition of the 2023 numbers was in line with the long term expectation from the models.
[Read more…] about Not just another dot on the graph? Part IICMIP6: Not-so-sudden stratospheric cooling
As predicted in 1967 by Manabe and Wetherald, the stratosphere has been cooling.
A new paper by Ben Santer and colleagues has appeared in PNAS where they extend their previous work on the detection and attribution of anthropogenic climate change to include the upper stratosphere, using observations from the Stratospheric Sounding Units (SSUs) (and their successors, the AMSU instruments) that have flown since 1979.
[Read more…] about CMIP6: Not-so-sudden stratospheric coolingReferences
- B.D. Santer, S. Po-Chedley, L. Zhao, C. Zou, Q. Fu, S. Solomon, D.W.J. Thompson, C. Mears, and K.E. Taylor, "Exceptional stratospheric contribution to human fingerprints on atmospheric temperature", Proceedings of the National Academy of Sciences, vol. 120, 2023. http://dx.doi.org/10.1073/pnas.2300758120