Clouds play a vital role in regulating our planet’s temperature.
They reflect sunlight back into space during the day, cooling the Earth, and trap heat at night, keeping it warm.
However, in a warming climate, cloud patterns are changing in ways that make global warming worse.
A new study led by Professor Johannes Quaas from Leipzig University and Hao Luo and Professor Yong Han from Sun Yat-sen University in China reveals that cloud cover is decreasing more during the day than at night, which amplifies global warming.
This new research, published in the journal Science Advances, shows that the cooling effect of clouds during the day is decreasing, while their warming effect at night is increasing.
This asymmetry, or uneven change, in cloud cover adds to global warming by creating a positive feedback loop.
In simple terms, this means that as the Earth gets warmer, the changes in cloud cover make it warm even faster.
The scientists used satellite observations and data from a comprehensive climate model project called CMIP6. These models include historical data from 1970 to 2014 and projections up to the year 2100.
By analyzing this data, the researchers found that globally, there are fewer clouds during the day and slightly more at night.
This leads to less reflection of sunlight during the day and more heat being trapped at night.
Climate models are essential tools for understanding and predicting the interactions within the climate system. They help scientists develop future scenarios and analyze the impacts of various factors such as greenhouse gases, aerosols, and clouds on the climate.
The study highlights the importance of considering the asymmetry in cloud cover changes in these models.
The asymmetry in cloud cover changes is mainly due to increased stability in the lower troposphere caused by rising greenhouse gas concentrations.
This stability makes it harder for clouds to form during the day, while at night, the clouds that do form are more stable and tend to increase. This results in less cloud cover during the day, allowing more sunlight to heat the Earth’s surface, and more cloud cover at night, trapping more heat.
Professor Quaas warns that this new understanding of cloud behavior means we need to work even harder to reduce greenhouse gas emissions. Not only do clouds respond to warming, but they also contribute to it through this newly discovered effect.
The scientists call for further studies to better understand these changes and their implications for our planet’s future.
Ongoing research at Leipzig University is also looking at changes in vegetation and air pollution to get a fuller picture of climate change impacts.
Source: KSR.
