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The report projects substantial warming and shifting precipitation patterns for the US Midwest, with extreme heat events and heavy rainfall becoming more frequent. Under a higher emissions scenario, end-of-century temperatures could rise by up to 10°F, significantly increasing the frequency of severe heat waves and reducing snow cover. While annual precipitation may only increase slightly, winter and spring are expected to become wetter, while summer precipitation may decrease under higher emissions. These changes are projected to increase heat-related mortality and flooding risks across the region.

The document details how a warming climate will increase the frequency and severity of heat waves and heavy precipitation in the Midwest, leading to higher mortality, infrastructure damage, and agricultural losses. It highlights specific risks to the Great Lakes shipping industry due to falling water levels and the threat to public health from water-borne diseases and combined sewer overflows in cities like Chicago and Milwaukee.

The document introduces a data set providing 14 city-relevant climate hazard indicators for 996 large cities, based on NEX-GDDP-CMIP6 downscaled climate simulations. It compares a 1994-2014 historical baseline against three warming scenarios (1.5°C, 2.0°C, and 3.0°C) to assist city decision-makers in strategic planning and risk management. Key findings indicate that at 3.0°C of warming, cities will experience heatwaves that are 28% longer and 25% more frequent on average than at 1.5°C, alongside increased energy demand for cooling and higher transmission risks for arboviruses.

Climate change increases human health risks in the U.S. through more intense heat waves, prolonged wildfire seasons, and severe flooding that compromises water quality. Specific examples include the increased likelihood of drought conditions similar to those seen in Texas in 2011 and the lengthening of allergy seasons.

The document identifies Hurricane Sandy as a demonstration of the United States' vulnerability to extreme weather and notes that human-induced warming is increasing the frequency and intensity of events such as heat waves, torrential downpours, and coastal flooding.

The document serves as a manual for journalists to avoid common errors when linking specific weather events to climate change. It details the methodology of 'event attribution studies'—which use climate models to compare the current world with a pre-industrial one—and provides specific guidance on reporting heatwaves, floods, tropical cyclones, heavy snowfall, droughts, and wildfires. The guide emphasizes that while climate change increases the probability and intensity of many extremes, it is rarely the sole cause, and local factors like land use and water management often play critical roles in turning a weather event into a disaster.

The document explains the science of extreme event attribution, which calculates how climate change alters the probability and intensity of specific weather events. It provides a detailed breakdown of how climate change influences heatwaves, floods, tropical cyclones, blizzards, droughts, and wildfires, while cautioning journalists against three common errors: ignoring climate change, attributing events without evidence, or treating climate change as the sole cause. It emphasizes that while global trends are clear for some phenomena (like heatwaves), others (like blizzards) remain highly uncertain.

The document explains how 'Extreme Event Attribution' research determines the extent to which climate change makes specific weather events more likely or intense. It warns journalists against three common errors: ignoring climate change, attributing events without evidence, or naming it as the sole cause. The guide provides detailed scientific contexts for heatwaves, floods, tropical cyclones, heavy snowfall, droughts, and wildfires, noting that while some links (like heatwaves) are globally certain, others (like droughts or snowfall) are more complex and region-specific.

The document explains 'extreme event attribution'—the scientific method used to determine if and how much climate change influenced a specific weather event. It warns journalists against three common mistakes: ignoring climate change, attributing events without evidence, or citing it as the sole cause. The guide provides detailed analysis for heatwaves, floods, tropical cyclones, heavy snow, droughts, and fires, noting that while heatwaves are unilaterally linked to global warming, other events like droughts and snowfall have more complex, region-specific relationships with climate change. It emphasizes that disasters result from both extreme weather and societal vulnerability.

The document explains the methodology of 'extreme event attribution' to help journalists avoid common errors, such as ignoring climate change or attributing an event to it as a sole cause. It details how scientists use climate models to compare the modern world with a pre-industrial one to determine if an event was more likely or intense due to global warming. The guide provides specific scientific consensus and limitations for heatwaves, floods, tropical cyclones, heavy snowfall, droughts, and wildfires, emphasizing that while some connections are robust (e.g., heatwaves), others are more complex and depend on regional data and human vulnerability.

The document explains the science of extreme event attribution, detailing how researchers use climate models and historical data to determine if climate change made a specific event more likely or intense. It provides specific guidance on reporting various phenomena—heatwaves, floods, tropical cyclones, snowfall, droughts, and wildfires—highlighting where scientific confidence is high and where uncertainties remain.

The document serves as a style guide for journalists to avoid common errors when attributing extreme weather to climate change. It explains the methodology of event attribution studies—comparing simulated worlds with and without human influence—and provides specific guidance on reporting heatwaves, floods, tropical cyclones, heavy snowfall, droughts, and wildfires. The guide emphasizes that while climate change increases the probability and intensity of many events, it is rarely the sole cause, and social vulnerability often determines whether a weather event becomes a disaster.

The study concludes that human-induced climate change made the March-April 2022 heatwave in India and Pakistan approximately 30 times more likely and about 1
C hotter than in a pre-industrial climate. The event, defined as a 1-in-100-year occurrence in today's climate, caused at least 90 deaths, triggered glacial lake outburst floods in northern Pakistan, and led to significant wheat crop yield losses in India, prompting a wheat export ban. The researchers warn that at 2
C of global warming, such heatwaves will become an additional factor of 2-20 more likely and 0.5-1.5
C hotter. Vulnerability is highest among outdoor daily wage earners and urban poor in informal settlements, though the report notes that Heat Action Plans in India, now covering 130 cities, can effectively reduce mortality.

The document explains 'event attribution' science, which quantifies how climate change alters the probability and intensity of specific weather events. It provides a detailed breakdown of how climate change affects heatwaves, floods, tropical cyclones, heavy snowfall, droughts, and wildfires, while cautioning journalists against common errors such as treating climate change as the sole cause of a disaster or ignoring it entirely. It emphasizes that while some trends are globally consistent (e.g., heatwaves), others are regionally variable or complex (e.g., droughts and snowfall).

The study finds that the July 2019 heatwave in Western Europe was made significantly more likely and intense by human-induced climate change. In France and the Netherlands, the event would have been extremely improbable without human influence, with return periods exceeding 1,000 years. Across all analyzed locations, the heatwave was 1.5 to 3 °C hotter than it would have been in an unchanged climate. The analysis utilized a combination of observational data and eight climate model ensembles, noting that while models generally underestimate temperature trends and overestimate variability, they still simulate large probability changes.

The document explains the methodology of extreme event attribution, which calculates how much climate change has altered the probability and intensity of specific weather events. It warns journalists against three common errors: ignoring climate change, attributing events without evidence, or citing it as the sole cause. The guide provides detailed analysis for heatwaves, floods, tropical cyclones, snowstorms, droughts, and wildfires, noting that while heatwaves are universally linked to global warming, other events like droughts and floods have more complex, region-specific relationships with climate change. It emphasizes that disasters are the result of both extreme weather and societal vulnerability, such as poor urban planning or water management.

The 2022 UK heatwave, which saw temperatures reach 40.3°C in Coningsby, was made at least 10 times more likely by human-caused climate change. Observational analysis indicates such an event would have been about 4°C cooler in pre-industrial times, though climate models systematically underestimate this trend. The event had significant impacts on human health, with projected excess mortality of over 840 people in England and Wales, and exposed critical vulnerabilities in UK infrastructure and urban planning.

The document explains 'extreme event attribution'—the scientific process of determining how climate change affects the likelihood and intensity of specific weather events. It provides a framework for journalists to avoid common reporting errors, such as ignoring climate change or attributing an event to it without evidence. The guide details the specific influence of global warming on heatwaves, floods, tropical cyclones, heavy snowfall, droughts, and wildfires, noting that while some links (like heatwaves) are globally certain, others (like droughts and floods) vary by region and are influenced by socio-economic vulnerabilities.

The study concludes that human-induced climate change significantly increased the probability of the 2022 summer soil moisture droughts in both West-Central Europe and the Northern Hemisphere extratropics, primarily driven by a strong increase in high temperatures rather than precipitation deficits. For West-Central Europe, the likelihood of root-zone soil moisture drought increased by 3-4 times and surface soil moisture drought by 5-6 times. In the Northern Hemisphere extratropics, the increase was more pronounced, with the likelihood of root-zone drought increasing by at least 20 times and surface drought by at least 5 times. These conditions led to severe impacts on agriculture, energy production, and water infrastructure, compounded by socio-economic stressors such as the conflict in Ukraine.

The study concludes that anthropogenic climate change made the record-breaking early season heat in northern Argentina and Paraguay approximately 60 times more likely. The analysis focused on the 7-day average of daily maximum temperatures, finding that the 2022 event was an exceptional occurrence that would have been unlikely without human-induced warming. The report also highlights the region's high vulnerability due to urban heat island effects, informal settlements lacking electricity, and the timing of the heatwave before populations had acclimated to summer temperatures.