Climate Shift Index Global July 2023

Analysis of July 2023, likely Earth's record hottest month, shows that human-caused climate change significantly increased the likelihood of extreme heat globally. Using the Climate Shift Index (CSI), the report finds that 6.5 billion people experienced at least one day where heat was at least three times more likely due to climate change. Particularly strong influences were noted in the Caribbean, Mexico, the southern U.S., and parts of Africa and Asia. In the U.S., 73% of the population experienced at least one day at CSI level 3 or higher, with several cities in Florida, New Mexico, and Arizona showing the strongest climate fingerprints.

• July 2023 is identified as very likely the record hottest month for Earth, with global temperatures continuously exceeding all prior recorded observations from July 3 through July 31. The global heat peaked on July 6 at 62.74° F (17.08°C), which was 0.50°F (0.28°C) higher than the previous record set in August 2016.
• A significant portion of the global population was exposed to heat intensified by climate change in July 2023. Approximately 6.5 billion people (81% of the global population) experienced at least one day at CSI level 3 or higher, and 50% of the population experienced at least 10 such days. On every day of the month, at least 2 billion people felt a very strong influence of climate change.
• The strongest climate fingerprints (CSI levels 4 and 5) were observed in several global regions, including north Africa (specifically Algeria), the Gulf of Guinea coastline, the Sahel, the Horn of Africa, the Arabian Peninsula, the Mediterranean Basin, the Malay Archipelago, the Amazon Basin, the Andes, Central America, the Caribbean, Mexico, the southern United States, northwest Canada, and the Canadian Arctic Archipelago.
• In the United States, 244 million people (73% of the population) experienced at least one day in July where temperatures were at least three times more likely due to human-caused climate change. The strongest fingerprints were found in the West (Nevada and central California), the Southwest, the South (Texas, Louisiana, and Mississippi), and the Southeast (Florida).
• Specific U.S. cities showed extreme climate signals; Cape Coral and Sarasota, Florida, had the highest average CSI levels at 4.6. Other cities including Tucson, Las Vegas, Mesa, Phoenix, and Henderson experienced 14-day heat events at CSI level 5, which are considered extremely unlikely without human-caused climate change.
• Extreme heat in North America led to significant agricultural and livestock losses in the U.S. Southwest and Northern Mexico, affecting coffee, sugarcane, corn, and soybeans, and causing the death of hundreds of cattle.
• In North America, 14 countries reached a July 2023 CSI of 5.0, with 11 of those being Caribbean small island developing states. This indicates that conditions in these areas would have been extremely unlikely without human-caused climate change.

APA

Climate Central (2023). Climate Shift Index Global July 2023. https://www.climatecentral.org/climate-matters/climate-shift-index-global-july-2023

Chicago

Climate Central. Climate Shift Index Global July 2023. 2023. https://www.climatecentral.org/climate-matters/climate-shift-index-global-july-2023.

Wikipedia

{{cite report |author=Climate Central |title=Climate Shift Index Global July 2023 |date=2 August 2023 |url=https://www.climatecentral.org/climate-matters/climate-shift-index-global-july-2023 |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{climatecentral2023climate, author = {{Climate Central}}, title = {{Climate Shift Index Global July 2023}}, institution = {Climate Central}, year = {2023}, month = aug, url = {https://www.climatecentral.org/climate-matters/climate-shift-index-global-july-2023}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }