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The analysis finds no significant evidence that human-caused climate change altered the probability or intensity of the October 2020 heavy rainfall events in Central Vietnam. While observations suggest a 1-in-80 year event, the uncertainty ranges for both observational and model-based data are too large to establish a significant climate change signal. The study concludes that natural variability currently outweighs climate change impacts for multi-day precipitation in the region, emphasizing the need for improved disaster risk reduction measures regardless of climate trends.

The report concludes that the June 2021 Pacific Northwest heatwave was virtually impossible without human-caused climate change, estimating it as a 1-in-1000 year event in the current climate. The analysis indicates the event was approximately 2°C hotter than it would have been in a pre-industrial climate and would have been at least 150 times rarer without anthropogenic warming. Future projections suggest that in a world with 2°C of global warming, such an event would occur every 5 to 10 years and be another degree hotter. Meteorological drivers included an 'omega-block' high-pressure system and dry antecedent soil conditions, while natural variability modes like ENSO and PDO played little to no role.

The July 2021 floods in Western Europe were driven by extreme rainfall from the low-pressure system 'Bernd', compounded by pre-existing wet soil conditions. While attribution for small catchments like the Ahr and Erft is challenging due to high natural variability, a broader 'Pooling Region' analysis indicates that climate change increased the intensity of maximum 1-day rainfall by 3-19% and its likelihood by a factor of 1.2 to 9 compared to a climate 1.2 °C cooler. Future projections suggest further increases in intensity and frequency in a 2 °C warmer climate.

The report concludes that the prolonged regional heat in Siberia from January to June 2020 was effectively impossible without human influence, with a best estimate probability ratio of 99,000 compared to a 1900 climate. Such events would have been at least 2°C cooler without anthropogenic influence. For the specific record of 38°C at Verkhoyansk, the study found a confident anthropogenic shift in intensity of 1.5°C, although the probability ratio for this specific station event is of lower confidence. By 2050, the regional heat is expected to be further intensified, with a synthesis change in intensity of 4.85°C compared to 1900.

The analysis finds that anthropogenic climate change has significantly increased the probability of extreme fire weather and heatwaves in southeastern Australia, while having no attributable trend in dry extremes. Specifically, the probability of a Fire Weather Index as high as in 2019/20 has increased by more than a factor of four since 1900. Heatwaves of similar intensity are now approximately 10 times more likely than they were around 1900. While climate change increased the overall risk, the specific severity of the 2019 event was further amplified by natural variability, specifically the Indian Ocean Dipole and the Southern Annular Mode.

The Union of Concerned Scientists (UCS) reports that 88 major carbon producers contributed more than half of the increase in ocean acidification and about half of the global temperature rise from 1880 to 2015. The document highlights that these companies, including investor-owned firms like ExxonMobil and Chevron, were aware of the climate risks of their products as early as 1965 but engaged in campaigns to sow doubt. It argues that these entities should be held financially responsible for climate-related damages, such as the $2 billion in additional costs attributed to sea level rise during Hurricane Sandy in New York City.

The study finds that the extreme two-day rainfall during Tropical Storm Imelda in September 2019 was made more likely and more intense by anthropogenic climate change. Observational data suggests the probability of such an event has increased by a factor of 2.6 since 1900, while climate model synthesis indicates a probability increase of 1.5 to 3.1 times and an intensity increase of 9% to 21%. The report also notes that rapid urban expansion and loss of impervious cover in Southeast Texas have exacerbated flooding risks for approximately 6.6 million people in the impacted counties.

The analysis finds that the July 2019 heat wave in Western Europe was made significantly more likely and more intense by human-induced climate change. In France and the Netherlands, the event would have been extremely unlikely without human influence, with return periods increasing by at least 10 times (and up to a hundred times). In the U.K. and Germany, the likelihood of such an event is estimated to be about 10 times higher (at least 3 times) due to climate change. Across all studied locations, temperatures would have been 1.5 to 3 ºC cooler in an unchanged climate.

The analysis concludes that human-induced climate change has made the June 2019 heatwave in France more likely and more intense. Observational data suggests that a heatwave of this intensity is occurring at least 10 times more frequently today than a century ago, with temperatures approximately 4C higher. While climate models qualitatively agree on the strong human influence, they show smaller trends and fewer severe heatwaves than observations, simulating a probability increase of between a factor of 2 and 20. The study emphasizes that early-season heatwaves in June have more severe health and organizational impacts than mid-summer events.

The document serves as a practitioner's guide for communicating climate change in developing nations. It emphasizes moving away from scientific jargon toward narratives that highlight the benefits of climate-compatible development, particularly for the poor. The guide outlines strategies for targeting diverse audiences—including governments, businesses, and the general public—and advocates for the use of 'demonstration effects' and data visualization to make climate risks tangible. It includes numerous case studies from Africa, Asia, and Latin America illustrating successful interventions such as participatory mapping, community radio, and the use of 'stranded assets' as a policy framework.

The World Weather Attribution (WWA) consortium investigated the possibility of analyzing the effect of climate change on Super Typhoon Mangkhut's rainfall but determined an analysis was not feasible. The decision was based on three primary constraints: the availability of only one high-resolution model for the region, poor quality of public observational data in the affected area (with 50% missing data in most stations), and a lack of manpower and stable funding. The document notes that while greenhouse gases are expected to increase the precipitation of the strongest storms globally, region-specific projections have low confidence. Additionally, the WWA stated that while sea level rise affects storm surges, such impacts are not currently part of their attribution assessments.

The World Weather Attribution (WWA) consortium states it is unable to conduct a formal analysis of climate change's effect on Hurricane Florence's rainfall due to observational challenges, a lack of high-resolution models, and insufficient funding and manpower. While acknowledging a separate study by Reed et al. and the general scientific consensus that global warming increases precipitation, the WWA notes that storm surges—affected by sea level rise—are also expected but are not part of their current attribution assessment.

The study assesses the 2018 heatwave in Northern Europe using observational data and climate models to determine the role of human-induced warming. It finds that the probability of such an event has increased across the region, with the most significant increases in probability estimated in Ireland, Denmark, and the Netherlands. While the heat was most extreme in the high Arctic (northern Finland), where it exceeded historical records, the risk ratio was more easily quantified in southern regions. The authors conclude that anthropogenic climate change made these heatwaves more likely, though the exact magnitude of the increase is harder to quantify in Scandinavia due to high natural variability.

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 document outlines the quantitative scoring system used to translate qualitative likelihood and confidence levels from the Climate Science Special Report (CSSR) and the IPCC Fifth Assessment Report (AR5) into a visual guide for extreme weather attribution in the continental United States.

The document outlines the development of 'climate attribution' science, which allows researchers to quantify the role of human-caused climate change in extreme weather. It identifies that evidence is strongest for heat waves, coastal flooding, and extreme precipitation, while remaining less conclusive for tornadoes and thunderstorms. The text provides specific examples of US events, such as Hurricane Harvey and the February 2017 heat wave, where climate change significantly increased likelihood or intensity.

The report synthesizes documentary evidence to show that major oil and gas companies were aware of the climate risks associated with their products as early as the 1950s. It argues that these companies had the capacity to foresee harms and the opportunity to mitigate them through technology and public warnings, but instead engaged in coordinated campaigns to sow scientific doubt. The document links this conduct to legal frameworks of responsibility in tort and human rights law, noting that attribution science now allows for the quantification of specific corporate contributions to global climate impacts.

The report examines the utility of extreme event attribution (EEA) through interviews with government officials and NGO representatives in Ethiopia, Kenya, and India. While generally viewed positively, the practical application of EEA varies by country and sector. In Ethiopia and Kenya, EEA is seen as a critical tool for securing international climate finance and improving drought early warning systems. In India, stakeholders expressed more skepticism, emphasizing the need for a 'critical mass' of studies to identify trends before the science can effectively influence national mitigation or adaptation agendas. Across all regions, significant barriers persist, including the high technical complexity of EEA outputs, a lack of predictive capacity for future events, and the need for down-scaled, non-technical communication to reach local communities and farmers.

The document details CDKN's support for Kenya's climate goals, highlighting the impact of the 2016 Climate Change Act and the National Climate Change Action Plan (NCCAP). Key achievements include a 140 MW increase in geothermal energy in 2015, the development of the CaRROT tool for the flower sector, and the submission of four proposals to the Green Climate Fund. It also discusses the 'Raising Risk Awareness' initiative for extreme event attribution and efforts to integrate water, energy, and food (WEF) security planning at the county level.

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.