SoylentNews is people
SoylentNews
A recent report on climate simulations show that global warming could break up stratocumulus clouds[$], letting in more energy as High CO2 levels break up stratocumulus cloud decks, once the levels rise above 1,200 ppm. Stratocumulus provide no precipitation but do cover about 20% of the low-latitude oceans and are especially prevalent in the subtropics, cooling by providing shade. If they disappear then, according to calculations, the added sunlight hitting the ground or ocean would increase temperatures by over 8°C.
Now, new findings reported today in the journal Nature Geoscience make the case that the effects of cloud loss are dramatic enough to explain ancient warming episodes like the PETM — and to precipitate future disaster. Climate physicists at the California Institute of Technology performed a state-of-the-art simulation of stratocumulus clouds, the low-lying, blankety kind that have by far the largest cooling effect on the planet. The simulation revealed a tipping point: a level of warming at which stratocumulus clouds break up altogether. The disappearance occurs when the concentration of CO2 in the simulated atmosphere reaches 1,200 parts per million — a level that fossil fuel burning could push us past in about a century, under “business-as-usual” emissions scenarios. In the simulation, when the tipping point is breached, Earth’s temperature soars 8 degrees Celsius, in addition to the 4 degrees of warming or more caused by the CO2 directly.
Once clouds go away, the simulated climate “goes over a cliff,” said Kerry Emanuel, a climate scientist at the Massachusetts Institute of Technology. A leading authority on atmospheric physics, Emanuel called the new findings “very plausible,” though, as he noted, scientists must now make an effort to independently replicate the work.
To imagine 12 degrees of warming, think of crocodiles swimming in the Arctic and of the scorched, mostly lifeless equatorial regions during the PETM. If carbon emissions aren’t curbed quickly enough and the tipping point is breached, “that would be truly devastating climate change,” said Caltech’s Tapio Schneider, who performed the new simulation with Colleen Kaul and Kyle Pressel.
Huber said the stratocumulus tipping point helps explain the volatility that’s evident in the paleoclimate record. He thinks it might be one of many unknown instabilities in Earth’s climate. “Schneider and co-authors have cracked open Pandora’s box of potential climate surprises,” he said, adding that, as the mechanisms behind vanishing clouds become clear, “all of a sudden this enormous sensitivity that is apparent from past climates isn’t something that’s just in the past. It becomes a vision of the future.”
(Score: 3, Informative) by Anonymous Coward on Tuesday February 26 2019, @07:33PM (6 children)
CO2 is around 411 ppm [noaa.gov] now, up from 400 ppm in 2015.
(Score: 3, Interesting) by DeathMonkey on Tuesday February 26 2019, @08:07PM (5 children)
And, thankfully, if you look at the record at your link thus far it's (basically) linear growth.
But what happens when permafrost starts melting....
(Score: -1, Offtopic) by Anonymous Coward on Tuesday February 26 2019, @08:14PM (1 child)
The beavers are already melting the permafrost. They have been melting it for awhile as they build their dams hoping for a better more comfortable life for themselves and their children.
(Score: 0) by Anonymous Coward on Tuesday February 26 2019, @08:57PM
Damn beavers!
(I couldn't resist)
(Score: 2) by fyngyrz on Tuesday February 26 2019, @09:13PM (2 children)
Yeah, 10 ppm in four years, more or less.
So 100 in 40 years. Assuming the linear trend continues, as you say.
--
Math puns are the first sine of madness
(Score: 2) by deimtee on Wednesday February 27 2019, @07:09AM (1 child)
So we will reach TFA's 1200ppm in 300 years, assuming the linear trend continues, as you say.
If you cough while drinking cheap red wine it really cleans out your sinuses.
(Score: 0) by Anonymous Coward on Wednesday February 27 2019, @01:36PM
humanity still sat Earthside unable to control climate, then teh stoopid species deserve to die off.