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An attribution study of heavy rainfall in coastal New South Wales from May 19-22, 2025, found mixed results regarding the influence of climate change. While observational data suggests a doubling in likelihood for the wettest four-day annual event in a 1.3°C warmer climate, climate models show substantial disagreement on rainfall trends for the region. The study emphasizes the need for flexible adaptation strategies due to this uncertainty.

The report finds that human-caused climate change significantly increased the frequency and intensity of extreme heat globally from May 2024 to May 2025. Approximately 4 billion people experienced at least 30 additional days of extreme heat, and 195 countries saw the number of such days at least double compared to a world without climate change. All 67 significant heat events analyzed were influenced by climate change, with some becoming dozens of times more likely. The authors emphasize that while adaptation strategies like City Heat Action Plans are vital, comprehensive mitigation through the phasing out of fossil fuels is the only way to limit future harms.

An event attribution study found that human-induced climate change increased the likelihood of the April 2025 extreme rainfall in the Central Mississippi river valley by approximately 40% and its intensity by 9%, though observational data suggests these increases could be as high as a factor of 2 to 5 in likelihood and 13-26% in intensity. The event caused at least 24 fatalities and estimated economic damages between $80 and $90 billion, with significant agricultural losses in Arkansas. The study highlights that while climate change amplified the event, effective early warnings from the US National Weather Service prevented a larger catastrophe, despite current staffing shortages in NWS field offices.

The Danger Season 2025 microsite integrates National Weather Service (NWS) alerts, population data, social disadvantage metrics from the Climate & Economic Justice Screening Tool (CEJST), Climate Central’s Climate Shift Index (CSI), and EPA/AirNow’s Air Quality Index (AQI). The methodology focuses on the period from May to October, identifying counties under extreme weather alerts or experiencing unhealthy air quality. It calculates four daily indicators: the total population facing alerts, the percentage of disadvantaged people affected, the percentage of the population facing at least one alert, and the proportion of extreme heat alerts attributable to climate change. The scope includes the contiguous United States, Alaska, Hawai'i, Puerto Rico, and the U.S. Virgin Islands, though certain datasets like CSI and AQI have specific geographic gaps.

In March 2025, 178 of 191 analyzed U.S. cities were warmer than normal, with an average temperature anomaly of 3.9°F. Texas and the Southwest saw the highest frequency of days where temperatures were at least twice as likely to occur due to climate change. Wheeling, West Virginia, recorded the highest anomaly at 9°F and is the fastest-warming station for March since 1970.

The report examines how a 21.8% rate hike for State Farm homeowners insurance in California, approved in March 2025 following devastating wildfires in Los Angeles, disproportionately affects policyholders in high-risk areas. It projects that the average State Farm policyholder in California will pay $841 more in 2025 than in 2023, with some communities seeing premiums more than double. The analysis highlights that 280,000 policyholders across 122 communities will face annual premium increases of $1,000 or more. The document argues that these escalating costs are a direct result of climate change and suggests that the financial burden should shift from policyholders to the oil and gas companies responsible for fossil fuel pollution.

A marine heatwave has affected the west coast of Australia since September 2024, with over 60% of the analyzed region meeting heatwave criteria by early January 2025. The most affected area is off the northwest coast, where temperature anomalies exceeded 1.5 degrees Celsius and some locations remained in a heatwave state for over 120 days. Analysis using the Ocean Climate Shift Index indicates that climate change made these daily ocean surface temperatures at least 20 times more likely on average, with likelihood increasing over 100 times during late November.

In December 2024, 166 out of 191 analyzed U.S. cities were warmer than normal, with the most significant anomalies occurring in Montana. While long-term warming trends are evident—with 189 of 191 stations showing positive trends since 1970—daily climate attribution via the Climate Shift Index (CSI) remained generally low, though specific cities in Puerto Rico, Hawaii, and Alaska saw several days where temperatures were significantly more likely due to climate change.

In January 2025, 166 out of 191 analyzed U.S. cities were cooler than normal, with the Ohio Valley and Southeast particularly affected. Despite these cool anomalies, no city set a low temperature record for January, and the warming influence of climate change remained pronounced. Alaska was the warmest state, with Fairbanks recording the highest anomaly at 14.6°F above normal. Analysis using the Climate Shift Index (CSI) showed that days where warmer temperatures were made at least twice as likely by climate change outnumbered days where cooler temperatures were made twice as rare.

The report finds that human-induced climate change significantly increased the frequency and intensity of extreme heat globally from May 2024 to May 2025, affecting billions of people and making all 67 identified significant heat events more likely. It highlights the disproportionate impact on vulnerable populations and the systemic failure to accurately document heat-related mortality, while advocating for a combination of urban heat action plans and aggressive fossil fuel mitigation.

The document explains that attribution science uses climate models and observational data to compare a world with human-induced warming to a fictional world without greenhouse gas emissions to determine the impact of climate change on specific weather events. It notes that 83% of such studies find a climate link and encourages journalists to explicitly connect these events to fossil fuel use and human vulnerability.

Climate Central's Ocean CSI analysis indicates that Cyclone Chido intensified over waters made significantly warmer by human-caused climate change, with some temperature spikes being up to 92 times more likely due to global warming.

A study by scientists from the Philippines, UK, and Netherlands found that human-induced climate change, primarily from burning fossil fuels, increased the likelihood of the potential intensity observed during the 2024 late typhoon season in the Philippines by a factor of 1.7. The analysis focused on the sequence of six storms hitting northern Luzon, including Super Typhoon Man-Yi, and found that the probability of at least three major typhoons making landfall in a single year has increased by 25% in the current 1.3°C warmed climate compared to a world without fossil fuel combustion.

The document outlines how warming winters in the US affect agriculture, health, and the economy, while offering reporting strategies and expert resources for journalists.

Climate change is significantly increasing the number of winter days with minimum temperatures above 0°C across the Northern Hemisphere. Analysis of the decade 2014-2023 shows that over one-third of analyzed countries and 44% of analyzed cities experienced at least one additional week of above-freezing days annually. Europe is the most affected region, with some countries like Lithuania and Latvia seeing over 20 additional above-freezing days per year. These shifts impact snowfall, the USD 12.5 billion winter sports industry, water supplies, and ecosystem health.

The 2024 Scorecard by Insure Our Future argues that the global insurance industry is in a 'vicious cycle,' where it continues to underwrite fossil fuel expansion while simultaneously withdrawing coverage from communities facing the resulting climate risks. Using climate attribution science, the report estimates that over one-third of weather-related insured losses between 2002 and 2022—approximately $600 billion—are attributable to human-caused climate change. The analysis reveals a stark mismatch in underwriting, with renewable energy premiums representing less than 30% of the size of the fossil fuel insurance market in 2023. For 15 of the 28 major property and casualty insurers analyzed, estimated climate-attributable losses exceeded the premiums they collected from fossil fuel clients. While Generali is noted as the first insurer to restrict oil and gas expansion across the entire value chain, the report concludes that voluntary corporate leadership has stalled, necessitating urgent regulatory intervention to mandate 1.5°C-aligned transition plans and higher capital requirements for fossil fuel exposure.

Attribution studies in Brazil indicate that fossil fuel combustion increased the likelihood and intensity of recent floods in Rio Grande do Sul and droughts in the Amazon. Despite these impacts, the Brazilian government continues to support oil and gas expansion, with plans to increase oil production by 63% and gas by 124% by 2032. Petrobras, which controls over 90% of domestic production, is estimated to be responsible for USD 500 billion in climate damages between 2018 and 2023. While Brazil has pledged to reduce emissions by up to 67% by 2035 and has successfully increased wind and solar power to reduce reliance on hydropower, its overall climate policies are rated as 'Insufficient' by Climate Action Tracker.

Climate change increased the maximum wind speeds of every Atlantic hurricane in 2024 by 3 to 14 mph, with some storms moving into higher Saffir-Simpson categories. The analysis, based on a rapid attribution framework, found that human-caused global warming elevated ocean temperatures by as much as 2.5°F, making elevated sea surface temperatures in hurricane tracks up to 800 times more likely.

In November 2024, the Western Pacific saw a record four simultaneous named tropical systems—Typhoon Yinxing, Typhoon Toraji, Super Typhoon Usagi, and Super Typhoon Man-Yi—all of which experienced rapid intensification due to warmer-than-average sea surface temperatures. Analysis using the Climate Shift Index: Ocean indicates these temperatures were made up to 40 times more likely by human-caused climate change. The Philippines was severely affected by 16 tropical cyclones or their remnants this season, resulting in at least 160 deaths and the displacement of over 9 million people due to flooding, landslides, and infrastructure damage.

In October 2024, 185 of 191 analyzed U.S. cities were warmer than normal, with the Southwest experiencing particularly high anomalies. The report highlights that 19 cities saw their hottest October on record and identifies specific states, including Texas, Arizona, and New Mexico, where climate change significantly increased the likelihood of extreme temperatures as measured by the Climate Shift Index.