A team of researchers from Israel and the United States recently discovered that the atmosphere may have a natural buffer against climate change.
Working with partners at John Hopkins University and NASA’s Goddard Space Flight Center, scientists from Hebrew University in Jerusalem focused their research on the effects of temperature and water vapor in an atmospheric region called the tropical tropopause layer (TTL) to better understand the impact of global warming.
Previous climate research has already established that water vapors play a critical role in climate change. As temperatures on earth heat up, more and more water is evaporated from the world’s oceans and waterways. This vapor eventually makes its way up into the Earth’s atmosphere, where it is thought, much like carbon emissions, to amplify the effects of climate change when it reaches the stratosphere.
In studying the TTL, the region of the atmosphere that straddles the troposphere below and the stratosphere above, Chaim Garfinkel of Hebrew University and the rest of the US-Israeli team traced the impact of water vapors on the less understood middle atmospheric layer, the TTL.
Using satellite observations and the results of chemistry-climate models, the team worked to find the correlations between temperature, water vapor, and the TTL region since 1979, focusing on regions above the world’s oceans.
Surprisingly, researchers found that while increased temperatures caused water vapor to rise in the lower atmosphere, resulting in clouds and precipitation, the TTL region above actually cooled and dried. As a result, less water vapor actually made its ways to the stratosphere, where it is known to impact climate change the most.
This may mean that nature has a natural defense against the man-made heating due to carbon emissions and other climate change factors.
“Since water vapor is a very strong greenhouse gas, this effect leads to a negative feedback on climate change,” the US-Israeli team concluded in their recently published research.
“Hence, this effect may actually slightly weaken the more dire forecasted aspects of an increasing warming of our climate,” the team stressed.