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Projections of near-term climate change are a potential research tool. However, for that tool to be most useful, the physical basis for a prediction must be made clear. The basis for our projection of record 2026 global temperature is high climate sensitivity, with its implication that aerosol cooling was still increasing during the period 1970-2005. One consequence, global sea surface warming, already has important effects. Causes of climate change must be understood for policy purposes. Figures in this post and our recent papers are continually updated on our website.[1] We are also now on Substack[2].

Even if global warming does not exceed two degrees, it could lead to more serious consequences than expected. This is the conclusion of a new study published in Nature.

The European Center for Medium Range Weather Forecasts (ECMWF) earlier this year issued a forecast of a strong (“Super”) El Nino to begin later this year and peak in early 2027, as we have discussed in two earlier posts.3,4 El Ninos are important because of the large effects that they have on global weather, even though those effects are not always consistent from one El Nino to another. El Ninos have even greater effect in combination with ongoing global warming, e.g., Radfar et al.5 find that the combination of an El Nino with increasingly prevalent marine heat waves results in tropical cyclones consistently producing higher maximum wind speeds, storm surges, and precipitation rates, and Liu et al.6 describe evidence of El Ninos strengthened control over global climate anomalies in a warmer world

Models are converging on prediction of an El Nino beginning this year, peaking in early 2027. After overlooking the possibility of an El Nino this year, some reporting is jumping on a “Super El Nino” bandwagon. El Nino strength and frequency are important, especially the issue of whether these are modified by global warming. However, the more important knowledge that needs to be extracted from near-term global warming concerns interpretation of ongoing, extraordinary, acceleration of ocean surface warming. Impacts of this ocean warming include a factor of two greater warming over land, increased extreme precipitation, and poleward movement of subtropical conditions.

After holding steady since the 1970s, warming in the last decade nearly doubled its pace, setting a track to 1.5 degrees before 2030

The world seems headed into another El Nino, just 3 years after the last one. Such quick return normally would imply, at most, an El Nino of moderate strength, but we suggest that even a moderately strong El Nino may yield record global temperature already in 2026 and still greater temperature in 2027. The extreme warming will be a result mainly of high climate sensitivity and a recent increase of the net global climate forcing, not the result of an exceptional El Nino, per se. We find that the principal drive for global warming acceleration began in about 2015, which implies that 2°C global warming is likely to be reached in the 2030s, not at midcentury.

The world seems headed into another El Nino, just 3 years after the last one. Such quick return normally would imply, at most, an El Nino of moderate strength, but we suggest that even a moderately strong El Nino may yield record global temperature already in 2026 and still greater temperature in 2027. The extreme warming will be a result mainly of high climate sensitivity and a recent increase of the net global climate forcing, not the result of an exceptional El Nino, per se. We find that the principal drive for global warming acceleration began in about 2015, which implies that 2°C global warming is likely to be reached in the 2030s, not at midcentury.

Global temperature in 2025 declined 0.1°C from its El Nino-spurred maximum in 2024, making 2025 the second warmest year. The 2023-2025 mean is +1.5°C relative to 1880-1920. The 12-month running-mean temperature should decline for the next few months, reaching a minimum about +1.4°C. Later in 2026, we expect the 12-month running-mean temperature to begin to rise, as dynamical models show development of an El Nino. We project a global temperature record of +1.7°C in 2027, which will provide further confirmation of the recent global warming acceleration.

Climate regime shifts (CRSs), characterized by abrupt and persistent transitions between alternative stable states in the climate system, pose serious threats to ecosystems and human well-being. Understanding the potential drivers of CRSs is crucial, particularly in a warming world where CRSs are becoming more frequent.

German scientists warn global warming is accelerating faster than expected, raising the risk of a 3 °C rise by 2050 and forcing Europe to confront unthinkable adaptation plans.

The Production Gap Report finds that 10 years after the Paris Agreement, governments plan to produce more than double the volume of fossil fuels in 2030 than would be consistent with limiting global warming to 1.5°C, steering the world further from the Paris goals than the last such assessment in 2023.

Several, more recent global warming projections in the coupled model intercomparison project 6 contain extensions beyond year 2100–2300/2500. The Atlantic meridional overturning circulation (AMOC) in these projections shows transitions to extremely weak overturning below the surface mixed layer (<6 Sv; 1 Sv = 106 m3 s−1) in all models forced by a high-emission (SSP585) scenario and sometimes also forced by an intermediate- (SSP245) and low-emission (SSP126) scenario. These extremely weak overturning states are characterised by a shallow maximum overturning at depths less than 200 m and a shutdown of the circulation associated with North Atlantic deep water formation. Northward Atlantic heat transport at 26°N decreases to 20%–40% of the current observed value. Heat release to the atmosphere north of 45°N weakens to less than 20% of its present-day value and in some models completely vanishes, leading to strong cooling in the subpolar North Atlantic and Northwest Europe. In all cases, these transitions to a

The startup Gigablue announced with fanfare this year that it reached a historic milestone: selling 200,000 carbon credits to fund what it describes as a groundbreaking technology in the fight against climate change . But outside scientists frustrated by the lack of information released by the company say serious questions remain about whether Gigablue’s technology works as the company describes. Their questions showcase tensions in an industry built on little regulation and big promises — and a tantalizing chance to profit.

In a rapidly changing climate, evidence-based decision-making benefits from up-to-date and timely information. Here we compile monitoring datasets (published at https://doi.org/10.5281/zenodo.15639576; Smith et al., 2025a) to produce updated estimates for key indicators of the state of the climate system: net emissions of greenhouse gases and short-lived climate forcers, greenhouse gas concentrations, radiative forcing, the Earth's energy imbalance, surface temperature changes, warming attributed to human activities, the remaining carbon budget, and estimates of global temperature extremes. This year, we additionally include indicators for sea-level rise and land precipitation change. We follow methods as closely as possible to those used in the IPCC Sixth Assessment Report (AR6) Working Group One report.

The human fingerprint on global warming was likely evident in Earth’s atmosphere far earlier than previously thought—even before the invention of modern cars, a new study says. Using a combination of scientific theory, modern observations and multiple, sophisticated computer models, researchers found a clear signal of human-caused climate change was likely discernible with high confidence as early as 1885, just before the advent of gas-powered cars but after the dawn of the industrial revolution.