Their study has found that climate change is leading to an increase in cloud cover, and this, in turn, is shrinking the difference between the daily maximum and minimum temperatures across the globe.

Decoding the impact of cloud cover on DTR To demystify this phenomenon of shrinking DTR, the research team listed down some factors that influence regional temperatures and simulated their effects on climate change using supercomputers. This helped them create a first-of-its-kind finer-resolution climate model with two square kilometer grids instead of the commonly used 100-kilometer grids, which allowed a close analysis of the complex interplay between land-surface processes and climate change.

Using the period between 2005-2014 as the baseline decade, the researchers ran different climate scenarios to project how the DTR in the two regions will change by the end of the century. Subsequent results showed the temperature gap closing by about 0.5°C in the temperate Kanto region and 0.25°C in the more tropical Malaysian peninsula. These changes were largely attributed to increased daytime cloud coverage that would be expected to develop under these climate conditions.

Understanding DTR impact is crucial to devise effective climate strategies "Clouds play a vital role in the diurnal temperature variation by modulating solar radiative processes, which consequently affect the heat exchange at the land surface," said Doan Quang Van, the lead author of the paper. This brings down the daily maximum temperatures, which is instrumental in closing the gap between daily high and low temperatures.

Climate projections indicate that both daily high and low temperatures will continue to increase as a consequence of climate change, although the former will do so at a slower rate