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In November 2024, 166 out of 191 analyzed U.S. cities were warmer than normal, with the South averaging 5.7°F above average. While long-term warming trends are evident—with El Paso, Texas warming 6.4°F since 1970—daily climate attribution signals (CSI 3 or higher) remained rare due to fall weather variability, though they were most prominent in Gulf Coast states and Puerto Rico.

The document describes a 'hazard synthesis' method developed by World Weather Attribution to combine different lines of evidence into a single number representing the influence of climate change on an extreme event's intensity and likelihood. It notes that while this approach is more realistic than using models or observations in isolation, it faces limitations when events would have been impossible in a cooler world or when climate models contradict basic physics, such as the Clausius-Clapeyron relationship. The author emphasizes that human expertise and experience are necessary to evaluate these results, as automated or AI-driven analysis cannot yet account for model deficiencies or data discrepancies.

The study finds that heavy precipitation events leading to severe flooding in Sudan are no longer rare in a climate 1.3°C warmer than pre-industrial levels, with such events now expected approximately every three years. Climate models indicate that human-induced warming has roughly doubled the likelihood of these events and increased their intensity by about 10%, with observed 30-day rainfall intensity in the study region increasing by 18% since 1981. The report emphasises that these climate risks are compounded by 'risk multipliers' including ongoing conflict, poverty, rapid urbanisation, and ageing infrastructure, which have created a displacement crisis in Sudan, Chad, and Nigeria. The authors argue that the transboundary nature of river systems in sub-Saharan Africa necessitates improved international coordination for flood management and early warning systems to mitigate future disasters as warming reaches 2°C.

The report finds that human-induced climate change increased the intensity and likelihood of heavy rainfall associated with Hurricane Milton in central Florida. Using the IRIS model, the analysis indicates that climate change increased the frequency of storms with Milton's wind speeds by approximately 40%, meaning the storm would have likely made landfall as a Category 2 rather than a Category 3 hurricane without global warming. Additionally, sea surface temperatures along Milton's track were 1°C warmer than in a world without climate change, making such temperatures 400 to 800 times more likely. The report also assesses Florida's adaptation measures, noting that while building codes are among the toughest in the US, the state's planning remains largely reactive and fails to adequately address social vulnerabilities in low-income and minority communities.

Between October 1 and 6, 2024, over 120 million people in Japan experienced unusual heat that was made at least 3 times more likely by human-caused climate change. At least 74 cities recorded temperatures of 30°C or higher, with conditions 5°C to 8°C above the 1991-2020 average. The analysis uses the Climate Shift Index (CSI), noting that 259 cities reached CSI level 3, while some cities like Kusatsu, Toyota, and Miyazaki reached CSI level 5, indicating an exceptional climate change event. The document also notes broader impacts of extreme heat in Japan, including a record 252 deaths in Tokyo from a summer heat wave, reduced agricultural output for vegetables, dairy, and fish, and delayed peak fall foliage in northern and eastern regions.

The guide advises journalists to contextualize floods within the broader framework of climate change, noting that a warmer atmosphere retains more moisture, leading to more frequent and intense extreme precipitation globally. It recommends avoiding probabilistic terms like "100-year flood" in favor of simple superlatives and suggests focusing on personal impacts and hyper-local infrastructure to make stories more relevant. The document also provides a curated list of mapping tools and data sources, such as NOAA, FEMA, and World Weather Attribution, to assist in reporting on flood risks and attribution.

In October 2024, 185 of 191 analyzed U.S. cities were warmer than normal, with 19 cities recording their hottest October on record. The Southwest experienced particularly high anomalies, and cities in California, Arizona, New Mexico, Texas, and Florida saw the highest frequency of days where temperatures were made at least three times more likely due to climate change.

Analysis by Climate Central indicates that June-August 2024 was the hottest season on record, with carbon pollution significantly increasing the frequency and intensity of risky heat days globally and in the U.S. Approximately 2 billion people worldwide experienced 30 or more risky heat days made at least three times more likely by climate change. In the U.S., the average person experienced 20 additional risky heat days, with the highest impacts concentrated in the South, Southeast, and Southwest, particularly in Florida and Puerto Rico.

The briefing links the increased frequency and intensity of US extreme weather events, such as the July 2023 heatwave and August 2024 California wildfires, to climate change driven by fossil fuels. It highlights that US oil and gas production emissions rose roughly 42% between 2011 and 2022 and notes that 88 large fossil fuel and cement companies are responsible for 48% of the rise in fire-danger conditions in the region. The document argues for corporate accountability, citing a Climate Analytics estimate that the 12 most polluting companies are responsible for USD 15 trillion in economic damages from 1985 to 2018. While the US has seen significant growth in solar and wind capacity and electric vehicle sales, primary energy consumption remains dominated by petroleum (38%), natural gas (36%), and coal (9%) as of 2023.

The document identifies a rapid increase in climate lawsuits against major fossil fuel producers, noting that annual filings nearly tripled since 2015. It categorizes these cases into primary types—most notably compensation for climate damages, misleading advertising, and emissions reductions—and highlights emerging trends such as criminal liability claims and challenges to project permitting. The analysis emphasizes the role of attribution science in quantifying corporate liability and the potential for landmark rulings, such as the one against Shell in the Netherlands, to set global precedents.

The report finds that August 2024 temperatures were elevated across much of the U.S., particularly in the South and Southwest, with Texas experiencing the highest anomalies. Using the Climate Shift Index (CSI), the analysis shows that the Southwest and South had the highest number of days where temperatures were at least three times more likely due to climate change. San Juan, Puerto Rico, recorded its hottest August on record, and Amarillo, Texas, was the most unusually hot city, 6.27°F above normal.

The report finds that September 2024 was unusually warm across much of the U.S., with 171 of 191 analyzed cities experiencing warmer-than-normal temperatures. While the highest temperature anomalies occurred in the Midwest and northern Great Plains, the strongest climate change signals (CSI values) were concentrated in the Southwest and Florida.

The Union of Concerned Scientists interviewed 19 legal experts to identify critical research gaps in climate litigation. The report categorizes these into three priority areas—attribution science, human health, and economic modeling—and five strategic areas, including greenwashing and emissions accounting. A central cross-cutting theme is the need for research on losses and damages. The authors emphasize that while IPCC reports provide a foundation, litigation requires more granular, geographically specific data and better communication between scientists and legal teams to overcome barriers such as differing timelines and data gaps in the Global South.

The study finds that climate change increased rainfall intensity in Taiwan and Hunan province and contributed to a 7% increase in maximum wind speeds for similar storms in the Western North Pacific basin. While sea surface temperatures as hot as those observed during Typhoon Gaemi were "almost impossible without climate change", the analysis did not identify a significant trend for rainfall in the northern Philippines. The report highlights that existing urban plans and flood infrastructure are unable to withstand climate-driven extreme floods, particularly in areas of unplanned urban development like Metro Manila.

The report finds that July 2024 temperatures were elevated in the eastern and western thirds of the United States, with the West Coast showing particularly high anomalies. Using the Climate Shift Index (CSI), the analysis identifies the Southwest as having the strongest climate signal, with cities averaging at least 14 days where temperatures were at least three times more likely due to climate change. Specific cities like Spokane, Washington, and Reno, Nevada, showed significant temperature anomalies and long-term warming trends since 1970.

The briefing establishes that fossil fuels are responsible for approximately 70% of carbon dioxide emissions since the industrial revolution, with a small number of companies contributing a disproportionate share. It highlights the role of attribution science in linking specific extreme weather events to climate change and details the growing trend of using the 'polluter pays' principle in litigation and legislation to hold these companies financially accountable. The document further argues that to meet the 1.5C target, global fossil fuel production must decrease significantly by 2030, supported by a transition to renewable energy and electric vehicles.

The report finds that June 2024 was historically hot across the United States, with climate change making temperatures 2.3 times more likely on average. The Southwest experienced the most extreme anomalies, with Nevada's temperatures being 8.2 times more likely due to climate change and the region seeing an average of 4.2 additional days above 90°F. Analysis of 191 ACIS stations showed that 12 experienced their hottest Junes on record, and 168 stations had at least one day where temperatures were at least twice as likely due to climate change.

Between June 16 and 24, 2024, approximately 4.97 billion people—over 60% of the global population—were exposed to extreme heat that was at least three times more likely to occur due to climate change. The analysis, using the Climate Shift Index (CSI), highlights severe impacts across India, China, Indonesia, Nigeria, Brazil, and the United States, as well as lethal heat waves in Saudi Arabia, Mexico, and Egypt.

The guide advises journalists to explicitly link extreme heat events to climate change and the burning of oil, gas, and coal, noting that heat is the deadliest extreme weather event. It provides sample language for reporting, recommends avoiding trivializing visuals, and suggests using tools like the Climate Shift Index for attribution.

The document serves as a '101' guide for journalists to report on climate change, explaining the difference between weather and climate, the primary causes of global warming, and the impacts of extreme weather. It offers specific phrasing to help reporters connect current events to climate change and distinguishes between mitigation and adaptation strategies. Additionally, it provides professional guidance on avoiding greenwashing, handling climate deniers, and centering climate justice in reporting, while emphasizing that climate coverage is based on scientific consensus rather than activism.