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An international team of scientists used a multi-method attribution approach to determine that anthropogenic climate change increased the likelihood of the 2015-2017 Western Cape drought by a factor of 3.3. The drought, characterized by three consecutive years of below-average rainfall, led to a severe water crisis in Cape Town, nearly resulting in 'day zero'. The study finds that drought risk in this region scales linearly with warming, suggesting that further temperature increases will continue to raise the probability of such extreme events.

The analysis finds that while the December 2017-January 2018 cold wave in the northeastern U.S. and southeastern Canada was not unprecedented in absolute terms, it is now a rare event due to global warming. Cold waves of this intensity have become approximately fifteen times less frequent over the last century, with temperatures of such events increasing by about 4ºF (2ºC). The study finds no evidence that Arctic warming has intensified these cold waves; instead, it suggests that Arctic air moving south is now less cold.

The document details findings from a study published in Climatic Change that attributes specific percentages of global warming and sea level rise to the largest carbon producers. It highlights that the 90 largest producers contributed 57% of the atmospheric carbon dioxide rise since 1880, while 50 investor-owned companies were responsible for roughly 16% of the temperature increase and 11% of sea level rise over the same period. The text argues that these companies knew of the risks as early as 1965 but chose to misinform the public.

The study concludes that anthropogenic climate change significantly increased the likelihood of the June 2017 heat event across Western Europe. Using observational data and multiple climate model ensembles, researchers found that such extreme heat is now more frequent, occurring every 10 to 30 years depending on the country. The risk ratio was highest in Portugal and Spain, where the probability of such heat increased by more than ten times due to global warming. The report also notes that under high-emission scenarios (RCP8.5), temperatures similar to June 2017 could become normal by the end of the century.

The analysis concludes that climate change had a small effect on the 2016 autumn drought in Somalia and Somaliland, with no significant trend in observed rainfall. However, a strong La Niña event significantly increased drought risks and explained approximately one third of the precipitation deficit. The severe food insecurity resulting from the drought was primarily driven by high human vulnerability caused by decades of conflict and political upheaval rather than meteorological factors alone.

A scientific study assessed the record-breaking rainfall in Chennai on 1 December 2015, which saw up to 494 mm of rain and caused US$3 bn in economic losses. The analysis concluded that no measurable effect of human-caused emissions was detected for this specific one-day event, attributing this lack of detection to the masking effects of aerosol pollution over India.

The report investigates the 51°C record temperature in Phalodi, Rajasthan, on 19 May 2016. While annual mean temperatures in India are increasing, the analysis found that human-induced climate change did not play a statistically significant role in this specific event or a similar 2015 event in Andhra Pradesh. The authors suggest that the warming effect of greenhouse gases may be masked by the cooling effects of aerosols and increased irrigation. However, the report warns that as energy policies shift away from fossil fuels, the diminishing cooling effect of aerosols could increase the intensity of future heat waves.

The report analyzes severe May 2016 rainstorms in Europe, finding that climate change significantly increased the probability of extreme 3-day rainfall in France's Seine and Loire basins, while results for southern Germany remained inconclusive.

The study investigates the 2014/15 drought in southeast Brazil, specifically focusing on the impacts in São Paulo. Using a multi-method approach including historical observations and climate model simulations, the researchers found limited evidence that human-induced greenhouse gas emissions increased the hydrometeorological hazard. Instead, the severe impacts on water supply were primarily attributed to rapid population growth and increased water consumption.

The study finds that while overall spring minimum temperatures are increasing, human-caused warming has advanced the start of the growing season (bud burst), exposing plants to more intense frosts. The April 2021 event in central France is attributed in part to this shift, with models projecting an increase in the frequency of such growing-period frosts in a 2°C warmer climate.

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 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 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 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.