Extreme Daily Temperature Swings Rising Worldwide: Study

AZERTAC/APP

Baku: Extreme day-to-day temperature swings have intensified markedly in recent decades, particularly in low- and mid-latitude regions where most of the world’s population lives, a study published in Nature has found, Anadolu Agency reported.

The research, conducted by scientists from Nanjing University and the Chinese Academy of Sciences, analyzed climate data from 1961 to 2020 and projections extending to 2100. It revealed that sudden, large temperature fluctuations from one day to the next — a largely overlooked form of extreme weather — are becoming more frequent, more intense, and larger in magnitude.

The study attributes this trend primarily to greenhouse gas emissions, with drier soils and increased variability in air pressure and soil moisture identified as key contributing factors. While high-latitude regions have experienced fewer swings, low- and mid-latitude areas in both hemispheres show a clear and accelerating increase.

Researchers warned that climate change is making daily weather far more volatile in warmer regions and that this volatility is expected to worsen through the end of the century.

Regions Most Affected

The strongest increases were recorded in the western United States, eastern China, parts of South America, and the Mediterranean basin. Over 10-year periods, intensity rises reached:

11.1°C in the western US

9.4°C in eastern China

12.4°C in South America

7.1°C in the Mediterranean

Record-breaking daily temperature swings were observed in 2022, with eastern China experiencing a 22.9°C shift and the western US recording 20.3°C. Such extreme events are now occurring far more often than under historical climate conditions.

The Main Driver

Deniz Demirhan, a climate scientist at Istanbul Technical University, told Anadolu that global warming amplifies day-to-day temperature variability in mid-latitudes while reducing it in polar regions.

“Climate change alters cloud patterns and atmospheric moisture, which directly affects daily temperature cycles,” Demirhan explained. “In some cases, increased cloud cover limits daytime heating and nighttime cooling, narrowing temperature ranges. In others, warming sharpens contrasts between day and night.”

She emphasized that greenhouse gas forcing is the main long-term driver, as rising concentrations disrupt Earth’s energy balance, warm the planet, and alter atmospheric circulation and surface processes.

In low- and mid-latitudes, this leads to variable pressure systems, drier soils, persistent high-pressure patterns, and frequent droughts, creating conditions for sharp heat spikes followed by sudden temperature drops. By contrast, rapid warming in the Arctic reduces the temperature gradient between the equator and the poles, resulting in fewer severe cold outbreaks and more moderate daily fluctuations at high latitudes.

Impacts on Health, Economy, and Agriculture

Demirhan warned that abrupt temperature swings can:

• Weaken immune systems
• Trigger cardiovascular and respiratory problems
• Increase mortality from strokes, heart attacks, and asthma attacks

Economically, such volatility can cause:

• Agricultural losses
• Sudden spikes in energy demand
• Strain on infrastructure
• Disruption of broader economic activity

Climate model projections for 2050–2100 indicate a significant rise in both the frequency and severity of extreme day-to-day temperature swings across low-, subtropical-, and mid-latitude regions. Under high-emissions scenarios:

• Frequency of extreme swings could rise by 17%
• Average magnitude could increase by 3%
• Annual accumulated heat load could climb by 20%

These projections are based on assessments by the Intergovernmental Panel on Climate Change (IPCC), the UN’s leading authority on climate science.

The findings suggest that sudden, unpredictable temperature fluctuations could become a defining feature of daily weather in many densely populated regions, posing growing challenges for public health, economies, and food security worldwide.