Populated Zones See Dramatic Increase in Daily Temperature Swings

(MENAFN) Day-to-day temperature volatility has escalated dramatically over recent decades, with the sharpest increases concentrated in low- and mid-latitude zones that house the majority of humanity, new research reveals.

Published in the journal Nature, the study—led by researchers from Nanjing University and the Chinese Academy of Sciences—examined historical climate records spanning 1961 through 2020 alongside future projections through 2100. The findings illuminate an underexamined dimension of extreme weather: abrupt, substantial temperature shifts occurring between consecutive days are growing more common, severe, and pronounced in scale.

Scientists pinpoint greenhouse gas emissions as the principal culprit, with diminished soil moisture levels and heightened fluctuations in atmospheric pressure and ground hydration serving as critical amplifying mechanisms. While polar regions have seen a decline in such temperature oscillations, equatorial and temperate zones across both hemispheres demonstrate unmistakable acceleration.

The research team cautioned that climate disruption is rendering daily weather patterns far less predictable in tropical and subtropical areas, with projections indicating continued deterioration through century's end.

The most dramatic intensification emerged in the western United States, eastern China, portions of South America, and the Mediterranean basin. Across decade-long intervals, intensity surges reached 11.1 degrees Celsius (20 degrees Fahrenheit) in the western US, 9.4C in eastern China, 12.4C in South America, and 7.1C in the Mediterranean.

Unprecedented single-day temperature shifts materialized in 2022, with eastern China documenting a 22.9C swing and the western US registering 20.3C. The analysis determined that such extreme-magnitude events now occur with far greater frequency than under pre-industrial climate baseline conditions.

Greenhouse forcing the main driver
Deniz Demirhan, a climate scientist at Istanbul Technical University, told Anadolu that global warming is amplifying 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 said. In some cases, increased cloud cover limits daytime heating and nighttime cooling, narrowing temperature ranges, while in others, warming sharpens contrasts between day and night.

She stressed that greenhouse gas forcing is the main long-term driver of changes in daily temperature variability, as rising concentrations disrupt Earth's energy balance, warm the planet and alter atmospheric circulation and surface processes.

In low and mid-latitudes, Demirhan said, this leads to more variable pressure systems, drier soils, persistent high-pressure patterns and frequent droughts -- conditions that allow 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.

MENAFN21012026000045017169ID1110630254