Climate Change Could Be Accelerated by Cloud Patterns
Clouds could dramatically increasing the rate of climate change, according to a report published in Science on Friday.
The consistency of clouds matters because the more ice particles they contain, the more they reflect sun radiation back into space, a process also known as "cloud albedo forcing." However, the more water particles the clouds contain, the more radiation they will let through into the earth's atmosphere.
The report explains that currently, conventional models have predicted the highest global temperature increase to be 4.6 degrees Celsius under the Equilibrium Climate Sensitivity — the relationship between concentrations of carbon dioxide and temperature in the atmosphere. However, cloud patterns, which have not been seriously considered until now, could increase that number as high as 5.3 degrees Celsius.
"Clouds are among the leading causes of this uncertainty," the study reads. "Here we show that the ECS can be up to 1.3 degrees Celsius higher in simulations where mixed-phase clouds consisting of ice crystals and supercooled liquid droplets are constrained by global satellite observations."
Yale graduate student Ivy Tan, who was part of the Yale-Lawrence Livermore National Laboratory team that produced the paper, warned the Guardian of the dangers this gap in scientific knowledge could present.
"Models have been systematically underestimating the amount of liquid in clouds, meaning that we aren't fully appreciating the feedback," Tan said. "It could mean our higher limit of warming is now even higher, depending on the model, which means serious consequences for us in terms of climate change.
"This is one of the largest uncertainties left in climate change," she added. "We need to understand these feedbacks a lot better."