Study Finds Sharp Rise in Extreme Daily Temperature Swings Worldwide
Extreme day-to-day temperature changes have increased sharply over recent decades, especially in regions where most of the global population lives, according to a new study published in the journal Nature.
The research shows that sudden shifts in temperature from one day to the next — a form of extreme weather that often goes unnoticed — are becoming more frequent, more intense and wider in range.
Research Scope and Key Findings
Scientists from Nanjing University and the Chinese Academy of Sciences analysed climate data from 1961 to 2020, alongside projections extending to the year 2100. Their findings reveal a clear upward trend in daily temperature volatility, particularly across low- and mid-latitude regions in both hemispheres.
By contrast, high-latitude areas have experienced fewer such extremes. However, researchers warned that overall daily weather patterns are becoming more unstable in warmer regions and will likely continue to worsen through the end of the century.
Regions Most Affected
The strongest increases in temperature swings appeared in the western United States, eastern China, parts of South America and the Mediterranean region.
Over 10-year periods, temperature intensity rises reached 11.1°C in the western US, 9.4°C in eastern China, 12.4°C in South America and 7.1°C in the Mediterranean.
In 2022, record-breaking daily temperature shifts occurred in several regions. Eastern China recorded a 22.9°C change, while the western US experienced a 20.3°C swing. The study noted that such extreme events now occur far more often than in past climate conditions.
Greenhouse Gases Drive Volatility
Climate scientist Deniz Demirhan of Istanbul Technical University said rising greenhouse gas emissions are the main cause of increasing daily temperature variability, particularly in mid-latitude regions.
She explained that climate change alters cloud cover, atmospheric moisture and air pressure patterns, all of which directly affect daily temperature cycles.
“In some situations, greater cloud cover limits daytime warming and nighttime cooling,” Demirhan said. “In others, global warming increases the contrast between heat and cold.”
She added that drier soils, persistent high-pressure systems and frequent droughts in low- and mid-latitudes allow sharp heat spikes followed by sudden cooling. Meanwhile, rapid Arctic warming reduces temperature differences between the equator and the poles, leading to fewer severe cold events in high-latitude regions.
Risks to Health and the Economy
Demirhan warned that sudden temperature swings can weaken immune systems and raise the risk of serious health problems. These include cardiovascular and respiratory stress, which can increase cases of heart attacks, strokes and asthma attacks.
Economically, she said, such volatility can damage crops, increase energy demand, strain infrastructure and disrupt wider economic activity.
Future Outlook Raises Concerns
Climate models for the period between 2050 and 2100 predict a significant rise in both the frequency and severity of extreme daily temperature swings across low, subtropical and mid-latitude land areas.
Under high-emissions scenarios, the frequency of these events could increase by 17%, their average intensity by 3% and the annual accumulated heat load by 20%, according to assessments by the Intergovernmental Panel on Climate Change.
The findings suggest that sudden and unpredictable temperature changes may become a defining feature of daily weather in many densely populated regions, creating growing challenges for public health, agriculture and global economies.
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