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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 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.

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 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.