We all know climate change is affecting weather systems and ecosystems around the world, but how and how it is still a topic of intense study. Newly designed simulations made possible by higher-powered computers suggest that cloud cover over oceans may die all the time once a certain level of CO2 has been reached, accelerating warming and contributing to a vicious cycle
A paper published in Nature details the new, far more detailed simulation of cloud formation and the effects of solar radiation thereupon. The researchers, from the California Institute of Technology, explained that previous simulation techniques were not nearly granular enough to resolve effects happening at the scale of meters rather than kilometers
These global climate models seem particularly bad at predicting the stratocumulus clouds that hover over the ocean ̵
As stratocumulus clouds cover 20% of the tropical oceans and critically affect Earth's energy balance (they reflect 30-60% of the shortwave radiation incident on them back to space1 ), problems simulating their climate change response to the global climate response
A more accurate and accurate simulation of the clouds was necessary to tell how increasing temperatures and greenhouse gas concentrations might affect them.
Thanks to "advances in high-performance computing and large-eddy simulation (LES) of clouds," researchers have been able to "faithfully simulate statistically steady states of stratocumulus-topped boundary layers in restricted regions. "And the" restricted region "in this case means the 5 × 5-km area simulated in detail.
The improved simulations have shown something nasty: when CO2 concentrations reached about 1,200 parts per million, this caused a sudden collapse of cloud formation as cooling at the top of the clouds is disturbed by excessive incoming radiation. Result (as you see at top): clouds do not form as easily, letting more sun in, making the heating problem even worse. The process could contribute as much as 8 or 10 degrees to warming in the subtropics
Naturally there are caveats: simulations are only simulations, though this one predicted today's conditions well and seems to accurately reflect the many processes going inside these cloud systems (and remember – inherent error could be against us rather than for us). And we're still a way out of 1,200 PPMs; current NOAA measurements put it at 411 – but steadily increasing
On the other hand, major climatic events like volcanoes can temporarily but violently change these measures, as has happened before; the Earth has seen such sudden jumps in temperature and CO2 levels before, and the feedback loop of cloud loss and resulting warming could help explain that. (19659002) "I think and hope that technological changes will slow carbon emissions so we do not actually reach such high CO 2 concentrations, "said CIT's Tapio Schneider, lead author of the study, in a news release. "But our results show that there have been dangerous climate change thresholds that we were not aware of,"
The researchers call for more investigation into the possibility of stratoculum instability, filling in the gaps they had to estimate in their model. The more brains (and GPU clusters) on the case, the better idea we'll have of how climate change will play out in specific weather systems like this one