Climate MattersAugust 14, 2023

Summer Heat Pushes 2023 Temperatures Near Record


  • 2023 has been the planet’s 3rd-hottest year on record through July, according to combined NOAA and NASA data.

  • Global temperatures through July 2023 were 1.29°C (2.32°F) above the 1881-1910 baseline, approaching record levels from 2016. 

  • This year has a 99% chance of finishing among the top five on record.

  • Warming will continue as long as carbon pollution continues. We have many options to cut carbon pollution from energy, transportation, agriculture, and more.

CM: 2023 Global Temperatures Near Hottest on Record (EN)
CM: 2023 Global Temperature Anomalies through July (EN)

Earth’s hottest month

July 2023 was the hottest month ever recorded on Earth—and by a wide margin. 

The year-to-date (January to July 2023) global surface temperature ranked 3rd warmest in the 144-year record at 1.29°C (2.32°F) above the early industrial (1881-1910) baseline average.

This follows June 2023, which set a record as the warmest June for the globe since NOAA's global records began in 1850. 

Global ocean surface temperatures also hit record highs in July, which marks the fourth month in a row with record-breaking ocean surface temperatures.

Warming planet, more extreme heat

The world saw a string of extreme weather and climate disasters last month, including persistent dangerous heat waves across the southern tier of the U.S. and the Caribbean as well as early season coral bleaching in the Florida Keys as ocean temperatures surged to unprecedented July levels.

Recent analysis using the Climate Shift Index®, Climate Central’s daily temperature attribution tool, indicates that human-caused climate change made July’s extreme heat events far more likely.

Globally, 6.5 billion people—81% of the global population—experienced at least one day at CSI level 3 or higher during July 2023. 

  • A CSI level 3 indicates local conditions that were made at least three times more likely due to climate change. 

In the U.S., 244 million people—73% of the population—experienced at least one July day with temperatures made at least three times more likely due to human-caused climate change.

U.S. cities with the strongest climate fingerprints on July heat were: Cape Coral, Fla.; Sarasota, Fla.; Bonita Springs, Fla.; Santa Fe, N.M.; Miami, Fla.; Mesa, Ariz.; Albuquerque, N.M.

CM: July 2023 Daily CSI Animation Contiguous United States (EN)

Heat waves such as those in the U.S. and around the globe this summer are the deadliest weather-related hazards

The rising global frequency and intensity of these devastating events is consistent with well-established scientific understanding of the consequences of carbon pollution—mainly from burning coal, oil, and natural gas. 

Global Temperature Outlook

According to NOAA, it’s virtually certain that 2023 will be a top 10 hottest year. There’s a 99% chance of 2023 ranking among the top five years on record.

Regardless of how 2023 ultimately ranks, the World Meteorological Organization estimates that there’s a 98% chance of at least one year between 2023 and 2027 exceeding the current warmest year on record (2016). 

According to the Intergovernmental Panel on Climate Change (IPCC), it is “unequivocal that human influence has warmed the atmosphere, ocean and land.” 

Global temperatures get an extra boost during El Niño years, when the warm phase of the El Niño-Southern Oscillation (ENSO) climate pattern is layered on top of the primary long-term warming trend due to carbon pollution. 

El Niño conditions emerged in May 2023, have strengthened since then, and are likely to continue through the Northern Hemisphere winter. 

CM: Global Temperature and ENSO 2023 (EN)
Click the downloadable graphic: Global Temperature and ENSO

Flirting with 1.5°C (2.7°F)

According to the Copernicus Climate Change Service, at several points during July 2023, global temperatures temporarily exceeded the 1.5°C threshold above the 1850-1900 average—a warming limit set in the Paris Agreement. 

Climate risks to ecosystems, human health, and livelihoods increase along with levels of warming, and every fraction of a degree of avoided warming matters. 

Nearly 200 countries—including the U.S.—have joined the Paris Agreement to limit warming to “well below 2°C (3.6°F)” with the ambition to limit warming to 1.5°C (2.7°F). 

The 1.5°C level specified in the Paris Agreement refers to sustained levels of warming over decades. Temporary (daily or monthly) exceedances like those observed in July 2023 are expected to occur more often as global temperatures approach the long-term threshold.

  • How close are we to reaching global warming of 1.5˚C? If greenhouse gas emissions continue on their recent path, the planet is likely to exceed 1.5°C of warming by the year 2034-2035 according to the latest estimates from the Copernicus Climate Change Service global temperature trend monitor tool and from Climate Change Tracker

Bending the curve

Warming will continue as long as we emit greenhouse gases that trap heat in the atmosphere, warm the planet, and lead to more frequent and intense extreme weather events. 

And global carbon dioxide (CO2) emissions from burning fossil fuels have only continued to climb

Annual CO2 Peak and Temperature - Peak CO2 & Heat-trapping Emissions
Annual CO2 Peak and Temperature
CM: Carbon's Continues to Climb (EN)
Click the downloadable graphic: Carbon's Continued Climb

Limiting warming to 1.5°C or 2°C will require global emissions to peak by 2025 at the latest—and “deep, rapid and sustained emissions reductions” throughout 2030–2050.

It will take major changes to bend the rising curves of CO2 and global temperatures, but we have many options to cut carbon pollution.

Every tenth of a degree of avoided warming counts toward a safer future, and there are dozens of options to reduce emissions in each sector of the economy (see Local Story Angles).


Three ways to cover climate solutions in your state:

  1. Climate Solutions in Every State reviews options to quickly reduce emissions in each U.S. state’s top-emitting sector. 

  2. WeatherPower: 2022 in Review shows that the U.S. produced enough wind and solar energy to power the equivalent of 64 million homes—reflecting a surge in the country’s low-carbon energy capacity that’s projected to continue.

  3. Climate Central’s Solutions Series of reports review options to cut emissions from energy, transport, agriculture, and buildings and bring the U.S. closer to its target of net-zero emissions by 2050.


Submit a request to SciLine from the American Association for the Advancement of Science or to the Climate Data Concierge from Columbia University. These free services rapidly connect journalists to relevant scientific experts. 

Browse maps of climate experts and services at regional NOAA, USDA, and Department of the Interior offices.  

Explore databases such as 500 Women Scientists, BIPOC Climate and Energy Justice PhDs, and Diverse Sources to find and amplify diverse expert voices. 

Reach out to your State Climate Office or the nearest Land-Grant University to connect with scientists, educators, and extension staff in your local area. 


Monthly global temperature analyses are independently calculated by NASA and NOAA/NCEI. Climate Central combines the NOAA and NASA information to re-baseline global temperatures using an earlier pre-industrial baseline of 1881-1910 in response to the Paris Climate Change Agreement. NOAA data begins in 1850 and NASA data begins in 1880. Climate Central’s rankings are based on the longest period of overlap, beginning in 1880. NASA’s calculations are extended to account for temperature changes at the poles, where there are fewer stations. NOAA does not use any extrapolation to account for low station density at the poles.