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The report investigates the 2022 Pakistan floods, focusing on two event definitions: 60-day maximum rainfall in the Indus basin and 5-day maximum rainfall in Sindh and Balochistan. While observational trends suggest that a 1.2°C warmer climate increased 5-day rainfall intensity by about 75% and 60-day rainfall by 50%, the authors refrain from a precise quantitative attribution due to high rainfall variability and climate model limitations. However, models project that a further 0.8°C of warming (reaching 2°C above pre-industrial levels) will significantly increase the intensity and probability of short-duration extreme rainfall. The study also highlights that the disaster's scale was exacerbated by outdated river management, high poverty, and gender-based vulnerabilities.

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 study investigates a severe drought in southern Madagascar (the Grand Sud region) between July 2019 and June 2021, which contributed to a major food security crisis. Analysis of observational data and climate models indicates that the event was a 1-in-135 year dry event, but its likelihood was not significantly increased by anthropogenic climate change. The findings suggest that natural variability remains the dominant driver of such droughts in this region, aligning with IPCC projections that perceptible changes in drought may only emerge if global mean temperatures exceed 2°C above pre-industrial levels. The report also highlights that the humanitarian impact was severely compounded by extreme poverty, poor infrastructure, and the COVID-19 pandemic.

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 report examines the 2022 food crisis in the Central Sahel, which followed an erratic 2021 rainy season characterized by delayed onset and short duration. Using three observational datasets and multiple climate models, the study finds that it is impossible to significantly link these specific monsoon characteristics to anthropogenic climate change due to large uncertainties and discrepancies. Instead, the crisis is attributed to chronic vulnerabilities, including extreme poverty, armed conflict, political instability, and global economic shocks such as the war in Ukraine and the COVID-19 pandemic.

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.

The study finds that while the 2022 drought in Central South America was primarily driven by natural variability and La Niña conditions, human-induced climate change exacerbated the event by increasing temperatures, which reduced water availability through higher evapotranspiration. The drought caused severe agricultural losses in Argentina, including a projected 25-50% decrease in soy yields and a significant drop in wheat production, while limiting potable water access for over 75,000 people in Uruguay.

The study concludes that human-induced climate change approximately doubled the probability of the April 2022 extreme rainfall event in Eastern South Africa and increased its intensity by 4-8%. While the event had a return time of about 20 years in the current climate, it would have been rarer in a 1.2°C cooler world. The disaster's impact was severely exacerbated by structural vulnerabilities, including the legacy of apartheid spatial planning and the prevalence of informal settlements in high-risk areas.

The study concludes that greenhouse gas and aerosol emissions contributed to the increased intensity and probability of heavy rainfall during the 2022 tropical storm events in Madagascar, Mozambique, and Malawi. While Tropical Storm Ana was a rare 1-in-50-year event for Mozambique and Malawi, Cyclone Batsirai was a more common 1-in-2-year event for Madagascar. The humanitarian impact was severely amplified by compound factors, including preceding floods, existing droughts in southern Madagascar, and high socio-economic vulnerability. Despite accurate forecasting by regional meteorological centers, infrastructure damage and a lack of trust in warnings hindered effective responses.

The study concludes that the June 2019 heat wave in France was made at least five times more likely due to human-induced climate change. Observational data suggests a much higher increase in probability and a temperature rise of approximately 4ºC compared to a century ago, though climate models generally show lower trends and systematic biases in representing heat wave variability.

The document explains how 'attribution' studies determine if global warming increased the likelihood or intensity of a specific extreme weather event. It warns journalists against three common errors: ignoring climate change, claiming it caused an event without evidence, or treating it as the sole cause. The guide provides specific findings for heatwaves, floods, tropical cyclones, heavy snowfall, droughts, and wildfires, noting that while heatwaves are globally linked to warming, other phenomena like droughts and floods vary significantly by region.

The document serves as a journalistic guide to 'event attribution', the scientific method used to determine if and to what extent climate change influenced a specific extreme weather event. It warns against common reporting errors—such as ignoring climate change, claiming it as the sole cause without evidence, or over-caution in reporting heatwaves—and provides specific scientific guidance on heatwaves, floods, droughts, wildfires, tropical cyclones, and heavy snowfall.

The document explains the methodology of extreme event attribution, which determines how much human-induced climate change has influenced the probability or intensity of a specific weather event. It provides a detailed breakdown of different types of extreme events—heatwaves, floods, tropical storms, snowfall, droughts, and wildfires—outlining where scientific confidence in climate links is high and where it remains uncertain. The guide emphasizes that while climate change influences the likelihood and severity of events, local vulnerabilities and human management often determine whether an event becomes a disaster.

The document explains the science of 'extreme event attribution,' which calculates how much climate change increases the probability or intensity of specific weather events. It warns journalists against three common errors: ignoring climate links, asserting links without evidence, or citing climate change as the sole cause. The guide provides specific scientific consensus and attribution examples for heatwaves, floods, tropical cyclones, heavy snow, droughts, and wildfires, emphasizing that while some events (like heatwaves) have a very strong global link to warming, others (like droughts or cyclones) are more complex and vary by region.