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Between December 2025 and February 2026, climate change significantly boosted global temperatures, with over one in six people experiencing strong climate influence daily. Nearly 228 million people faced 30 or more risky heat days added by climate change, with 81% of these individuals residing in Africa. The analysis highlights that in 45 countries, all risky heat days during this period were driven by climate change, and 124 countries saw the average person experience at least 30 days of strong climate influence (CSI level 2 or higher).

The report finds that June through August 2024 was Earth's hottest season on record, with human-induced climate change significantly increasing the frequency and intensity of extreme heat worldwide. Using the Climate Shift Index (CSI), the analysis shows that one in four people experienced temperatures made at least three times more likely by climate change every day of the season. Global exposure peaked on August 13, 2024, affecting 4.1 billion people. The average person experienced 17 additional 'risky heat days' (temperatures above the 90th percentile) due to climate change. Over 2 billion people experienced 30 or more such days, with extreme concentrations in the Caribbean, Western Asia, Micronesia, Northern Africa, and Southern Europe. Additionally, 72 countries experienced their hottest June-August period since 1970, and 180 Northern Hemisphere cities faced dangerous extreme heat waves that were, on average, 21 times more likely due to human-caused warming.

Climate Central analyzed the urban heat island (UHI) index across 65 major U.S. cities, finding that 68% of the 50 million residents in these cities live in areas where the built environment increases temperatures by 8°F or more. The study identifies albedo, green space, and population density as the primary drivers of this effect. It also highlights a link between historical redlining and current heat disparities, noting that in 84% of 179 analyzed cities, historically redlined areas experience hotter summers than non-redlined areas.

Between March and May 2024, global temperature records were broken for three consecutive months. Using the Climate Shift Index (CSI), the analysis found that approximately one in four people worldwide experienced temperatures at least three times more likely due to climate change (CSI level 3+) daily. Exposure peaked on April 6, 2024, with 2.7 billion people affected. The most severe impacts were concentrated in Africa, Southeast Asia, Central America, and South America, with 44% of Africa's population experiencing the most extreme attributable heat (CSI level 5 for 60+ days). The report also highlights a strong regional contrast in the U.S., where coastal areas and islands showed higher CSI signals despite lower temperature anomalies compared to the Upper Midwest.

Between December 2023 and February 2024, carbon pollution drove abnormal warmth for approximately 80% of the global population. Roughly 4.8 billion people experienced at least one day of temperatures that would be 'virtually impossible' without climate change. The report highlights extreme temperature anomalies in the U.S. upper Midwest and Canada, as well as high Climate Shift Index (CSI) levels in tropical regions of Southeast Asia, Sub-Saharan Africa, and the Caribbean. It also documents associated extreme weather events, including record-breaking heat in Australia and deadly floods in the Democratic Republic of the Congo.

The period from November 2022 to October 2023 was the hottest 12-month stretch in recorded history, with a global average temperature 1.32°C above the pre-industrial baseline. Using the Climate Shift Index (CSI), Climate Central found that 90% of the global population (7.3 billion people) experienced at least 10 days of temperatures very strongly affected by climate change (CSI level 3 or higher). Approximately 1.9 billion people (24%) experienced a five-day heat wave strongly influenced by carbon pollution (CSI level 2 or higher). The report highlights an inequitable distribution of impacts, with small island developing states and least developed countries facing higher exposure, although heat waves also occurred in G20 nations. The analysis also links human-induced climate change to severe weather events, including deadly flooding in Africa and Libya, and record-breaking wildfires in Canada and Hawaii.

Analysis using the Climate Shift Index (CSI) shows that human-caused climate change significantly increased the likelihood of record-shattering heat during the June-August 2023 period. Approximately 48% of the global population experienced at least 30 days where heat was made at least three times more likely by climate change (CSI level 3 or higher). The report highlights a stark inequity in exposure, noting that countries with the lowest historical emissions experienced three to four times more days of very strong climate fingerprints than G20 countries.