Climate UncensoredJames Hansen, Pushker Kharecha, Dylan Morgan and Jasen Vest 30 April 2026 Fig. 1. Global surface temperature anomaly in GISS analysis[1] relative to 1880-1920 mean. Abstract. We infer that 2026 is likely to be the warmest year in the period of instrumental data, based on a physics-based approach with identifiable assumptions. This approach may help us learn something in 2026 about the mechanisms of climate change. A Carbon Brief article last week (“Strong El Nino Puts 2026 on Track for Second Warmest Year”)[4] makes us wonder about the basis for such expert projection. We are reminded of IPCC (Intergovernmental Panel on Climate Change) expert projections with unstated assumptions and whose physical basis is inscrutable to the public. Organized climate model runs for the Climate Model Intercomparison Project (CMIP) are valuable for climate analyses, but the fog of all model results should not be misinterpreted as a probability distribution for the real world. Fig. 2. Earth’s satellite-observed absorbed solar radiation (ASR) and longwave (thermal) emission to space (LW),[7] both relative to their 2000-2010 averages, and the absolute Earth energy imbalance (EEI) calibrated with aid of Argo-measured heat storage in the ocean.[8] Outline of discussion: (1) we look at up-to-date data for Earth’s energy imbalance, which is the ultimate drive of global temperature change, (2) we discuss ongoing changes of climate forcings, (3) we look at changing global SST (sea surface temperature), a useful, stable diagnostic, (4) we project likely 2026 temperature based on these data. As 2026 progresses, we will update the data for the sake of learning something relevant to longer-term climate change. Fig. 3. Global surface temperature (relative to 1880-1920 base period).[1] There are many reasons to suspect that the rate of change of the net climate forcing will diminish in the near-term, as we will discuss. However, the best measure of the situation at this time is provided by the Earth’s radiation balance data (Fig. 2). During the 10 years 2015-2024, Earth’s energy imbalance (EEI), the drive for global warming, was about double the 0.6 W/m2 mean of 2000-2014.[10] In the 13 months January 2025 through January 2026 the mean EEI is 1.5 W/m2. Thirteen months is too short a period to judge trends in EEI because of the impact of cloud variability, but the fact is that, as yet, there is no slowdown in this drive of climate change. Fig. 4. NOAA OISST V2.1 Image Credit: ClimateReanalyzer.org, Climate Change Institute, University of Maine. The red curve is 2026; the heavy grey curves are 2024 (upper figure) and 2023 (lower figure). On the other hand, we have knowledge of exceptional, ongoing, acceleration of global warming. Comparison of 2026 with 2023, the Nino-origin years, shows 2026 SST as consistently about 0.13°C warmer than 2023. Given our assumption that the present El Nino will be of similar strength to that in 2023, we expect the 0.13°C temperature gap to be maintained. Temperature change over land exceeds that over ocean by a factor of 2 (Fig. 5), so, given that land covers 30% of the globe, the ocean gap of 0.13°C implies a global warming of 2026 relative to 2023 of 0.17°C – in fact, the 2026 warming relative to 2023 in the GISS analysis is 0.17°C. Fig. 5. Comparison of land and ocean temperature anomalies relative to 1880-1920 (see our data page). Global temperature in 2024 was 0.11°C higher than in 2023. Thus, if 2026 ultimately exceeds 2023 by 0.17°C, it would break the 2024 global temperature record by 0.06°C. That margin is wide enough that we are willing to make the prediction that 2026 will be the warmest year in the period of instrumental temperature measurements. Of course, 2027 will be still hotter. [1] Temperature is from Goddard Institute for Space Studies analysis described by Hansen J, Ruedy R, Sato M et al. Global surface temperature change, Rev Geophys 48, RG4004, 2010; Lenssen NJL, Schmidt G, Hendrickson M et al. A NASA GISTEMPv4 Observational Uncertainty Ensemble, J Geophys Res Atmos 129, e2023JD040179, 2024 [2] Our communications (posts) and data are available now via Hansen’s website while we continue to develop and populate our websites and data pages. Figures in communications and papers that remain of current interest will be updated at appropriate intervals, usually monthly, with the most recent date of update indicated on the website. [3] https://jimehansen.substack.com/ [4] Hausfather Z. Strong El Nino Puts 2026 on Track for Second Warmest Year, Carbon Brief 21 April 2026 [5] Hansen J. A climate talk in Helsinki, 7 November 2025 [6] Hansen JE, Kharecha P, Sato M et al. Global warming has accelerated: are the United Nations and the public well-informed? Environ.: Sci. Pol. Sustain. Devel. 67(1), 6–44, 2025 [7] Loeb NG, Johnson GC, Thorsen TJ et al. Satellite and ocean data reveal marked increase in Earth’s heating rate. Geophys Res Lett 48, e2021GL093047, 2021 [8] von Schuckmann K, Cheng L, Palmer MD et al. Heat stored in the Earth system: where does the energy go? Earth Sys Sci Data 12, 2013-41, 2020 [9] Hansen J, Sato M, Ruedy R et al. Forcings and chaos in interannual to decadal climate change. J Geopys Res 102, 25, 679-720, 1997 [10] The value 0.61 W/m2 (Fig. 2) is for the 15 years from January 2001 through December 2015. The value for the first 15 years of data, March 2000 through February 2015 is 0.60 W/m2. Thanks for reading Climate Uncensored! Subscribe for free to receive new posts and support my work. Thanks for reading Climate Uncensored! This post is public so feel free to share it. © 2026 James Hansen |