Climate change is closing Daily temperature difference, Clouds could be the cause – Emerging for it?

news7g10/26/2022

3 3 minutes read

Climate change is closing Daily temperature difference, Clouds could be the cause - Emerging for it?

[This appears to be conflating a contamination of temperature records with an actual observed phenomenon. Increasing night time temperatures, thus reducing the Day/Night difference, is a known and studied result of urbanization. -charles]

The diurnal temperature range has a significant effect on growing seasons, crop yields, residential energy consumption, and heat stress-related human health problems.

A peer-reviewed publication

UNIVERSITY OF TEXAS IN AUSTIN

Climate change is narrowing the difference between daily highs and lows in many parts of the world. The distance between the two, known as the diurnal temperature range (DTR), has a significant effect on growing seasons, crop yields, residential energy consumption, and human health problems associated with it. heat stress. But why and where the DTR is shrinking due to climate change remains something of a mystery.

Researchers are part of a new international study that examined DTR in late 21^st century believe they have found the answer: An increase in clouds, blocking shortwave radiation coming from the sun during the day.

This means that while both daily maximum and daily minimum temperatures are expected to continue to increase with climate change, daily maximum temperatures will increase at a slower rate. . The end result is that the DTR will continue to shrink in many parts of the world, but the changes will vary depending on many local conditions, the researchers said.

The study was published in the journal AGU . Geophysical Research Letter, was the first to use high-resolution computer modeling to delve deeper into Earth’s shrinking DTR, particularly how it relates to cloud cover.

“Clouds are one of the major uncertainties in terms of climate forecasting,” said co-author Dev Niyogi, a professor at the University of Texas at Austin Jackson School of Geosciences. “When we do this with a modeling framework that has a very high spatial resolution, it allows us to simulate clouds explicitly.”

Lead author Doan Quang Van, assistant professor at the Center for Computational Science at the University of Tsukuba, Japan, says this is important for understanding the future of DTR.

“Clouds play an important role in diurnal temperature variation by regulating solar radiation processes, thereby influencing heat exchange at the land surface,” he said.

The research team included scientists from UT Jackson’s Department of Geosciences, the National Center for Atmospheric Research in Boulder, Shanghai University of Science and Technology, the National Defense Academy of Japan, and the University of Tsukuba. in Japan. Modeling work using supercomputers at University of Tsukuba Center for Computational Science.

Using supercomputers, the team was able to model the complex interplay of terrestrial processes on climate change. These include changes in land use (such as deforestation), soil moisture, rainfall, cloud cover, and other factors that can affect temperatures in a local area. By creating a model with a better resolution grid – the 2 square km grid instead of the 100 km grid used in most climate models – the researchers were able to more closely analyze the impacts of climate change.

The team focused on two regions: the Kanto region of Japan and peninsular Malaysia. They used the 10-year period from 2005-2014 as a baseline and then ran different climate scenarios to predict what would happen to the DTRs in the two regions by the end of the century. They found that the temperature gap narrowed by about 0.5 degrees Celsius in the temperate Kanto region and 0.5 degrees Celsius in the more tropical peninsular Malaysia. The researchers suggest that these changes are largely due to increased daytime cloud cover, which is expected to develop in this climate.

This study could help scientists improve current global climate models and aid in understanding how the shrinking DTR will affect society and the environment as the climate continues, the researchers say. Warming.

“It is very important to know how DTR will change in the future as it regulates the metabolism of humans, animals and plants,” said Quang Van. “It also regulates local atmospheric circulation such as sea-land winds.”

The research was funded by the Association for the Advancement of Science in Support of Scientific Research (KAKENHI), NASA’s Interdisciplinary Research in Earth Sciences, and the US Department of Agriculture’s National Food and Agriculture Institute.