A small number of cities have recorded statistically significant daytime cooling trends even as the planet’s average temperature continues to rise, according to an analysis of satellite observations from about 1,400 cities worldwide.
The finding does not contradict global warming. Instead, it shows why climate change is not experienced in the same way in every place, or as a smooth upward movement in temperatures. Local conditions, including sunlight, cloud cover, atmospheric circulation and humidity, can alter how heat is distributed and measured across regions.
Most cities are still warming
The study examined satellite records collected between 2002 and 2021. It found that the overwhelming majority of cities experienced warming in their daytime land surface temperatures. This measurement refers to the temperature of the ground and built surfaces detected by satellites, rather than directly measuring the air people breathe.
| Measurement | Finding |
|---|---|
| Daytime warming | 86% of cities |
| Night-time warming | 96% of cities |
| Statistically significant daytime cooling | 3.9% of cities |
| Statistically significant night-time cooling | Negligible |
“Statistically significant” means that the observed trend is unlikely to be explained by random variation alone under the methods used in the study. It does not mean that every part of a city is becoming colder, or that a single cold season has reversed the longer-term climate trend.
Cold extremes can occur in a warming world
The contrast between global averages and local conditions was particularly clear in January 2026. The global average surface air temperature stood at 12.95°C, which was 0.51°C above the 1991-2020 average. At the same time, large parts of the Northern Hemisphere experienced severe cold.
Temperatures in Lappeenranta, Finland, fell to -31.5°C, while parts of Siberia recorded temperatures of about -40°C. New York’s Central Park received 29 centimetres of snow on 25 January, its biggest single-storm snowfall in nearly four years. Russia’s Kamchatka Peninsula received more than two metres of snow during the first two weeks of January, and the northern Japanese city of Aomori recorded a snow depth of 1.7 metres on 3 February, its highest in 40 years.
These events happened during the same period in which Renmark in Australia reached 49.6°C on 26 January, its hottest day on record. The examples illustrate an important distinction: weather describes short-term conditions in a particular place, while climate describes patterns over longer periods. A cold spell, even an exceptional one, does not by itself demonstrate that global warming has stopped.
Why regional differences matter
Global warming refers to the rise in Earth’s average temperature. That average combines conditions across oceans, continents, seasons and regions. It therefore cannot predict the temperature of every city on every day. Changes in cloud cover may reduce the amount of sunlight reaching the surface, while shifts in atmospheric circulation can move cold or warm air into areas that usually experience different conditions.
Humidity also influences how heat is stored and transferred. These factors can produce sharp regional contrasts, including cold extremes in one part of the world while another experiences record heat. The source material also identifies El Niño, a natural climate phenomenon, as partly contributing to the recent increase in temperature variability.
- A warming global average does not mean every city warms at the same speed.
- Daytime cooling was identified in a small minority of cities, while night-time cooling was negligible.
- Short-term cold events must be assessed separately from long-term climate trends.
For the public, the central message is that individual weather events should not be used as a simple test of whether climate change is occurring. The wider evidence in the city analysis points to continued warming in most locations, alongside increasing regional volatility. Understanding both parts of that picture is important for interpreting extreme weather and for planning around the conditions communities may face in future.
