The Exceptional Rise Global Tropospheric Temperature over 2022-2024

The global tropospheric temperature hit an all-time maximum in 2023. While new global average temperature records are routinely set as a result of greenhouse warming, the year-to-year rise in temperature from 2022 to 2023 is infrequently reproduced in climate models (e.g., Raghuraman et al. 2024). It is possible that such a rise in temperature could result from a unique manifestation of internal climate variability (e.g., Cattiaux et al. 2023). Earth recently experienced a transition from a prolonged La Niña event to an El Niño event. This phasing of ENSO variability is associated with increased odds of a spike in global temperature in climate models (e.g., Raghuraman et al. 2024). Other analyses indicate that multi-year trends in low cloud cover, aerosols, and the peak of the 11-year solar cycle are also important factors (e.g., Goessling et al. 2024). Now into 2025, we find that the year-to-year rise in temperature (over 2023 to 2024) is again large and the annual mean global tropospheric temperature anomaly (in 2024) exceeds the record set in the previous year. We examine the rapid and persistent rise in global tropospheric temperature using microwave-based measurements of tropospheric temperature from satellites. We contextualize the exceptional 2023-2024 warmth using model simulations of the a) pre-industrial period and b) the satellite era in order to estimate the effects of internal variability and greenhouse warming. We also explore the sensitivity of our results to model climate sensitivity and the representation of interannual variability with data from several large initial condition ensembles.

Cattiaux, J., Ribes, A., & Cariou, E. (2024). How extreme were daily global temperatures in 2023 and early 2024? Geophysical Research Letters, 51(19). https://doi.org/10.1029/2024gl110531

Goessling, H. F., Rackow, T., & Jung, T. (2024). Recent global temperature surge intensified by record-low planetary albedo. Science. https://doi.org/10.1126/science.adq7280

Raghuraman, S. P., Soden, B., Clement, A., Vecchi, G., Menemenlis, S., & Yang, W. (2024). The 2023 global warming spike was driven by the El Niño–Southern Oscillation. Atmospheric Chemistry and Physics, 24(19), 11275–11283. https://doi.org/10.5194/acp-24-11275-2024

Research at Lawrence Livermore National Laboratory was performed under the auspices of U.S. DOE Contract DE-AC52-07NA27344. This research was performed as part of the PCMDI Project, which is funded by the RGMA program area of the Office of Science at DOE.