Rising CO2 Levels Could Wipe Out Stratocumulus Clouds, Accelerating Climate Change

By Roni Dengler | February 26, 2019 4:00 pm
stratocumulus clouds climate change

New models of rising CO2 levels suggest climate change could eventually wipe out Earth’s stratocumulus cloud cover. (Credit: Chris Cornish/shutterstock)

Stratocumulus clouds spread out like puffy cotton balls in orderly rows above the ocean in the sub-tropics. The low-hovering clouds provide the planet shade and help keep Earth cool. But in a new study published this week, researchers say that rising carbon dioxide levels in the atmosphere could wipe out these clouds. The discovery means that, under “business as usual” emissions scenarios, Earth could heat up 14 degrees Fahrenheit within a century.

“We are perturbing a complex system that we do not fully understand yet, and the system may well respond in surprising and nonlinear ways,” said Tapio Schneider, a climate scientist at the California Institute of Technology in Pasadena, who led the new research. His team’s results are “a warning shot” for the future,” he says.

Cloud Cover

Stratocumulus clouds act like a shade umbrella for the planet. The low clouds reflect some 30 to 60 percent of sunlight back into space. Although they are Earth’s most frequent cloud type and cover nearly 20 percent of the tropical oceans, global climate models have difficulty simulating them.

Part of the problem is that clouds drive climate processes on scales too small for our current computer models to resolve. Instead, current global climate models approximate the impact of these cloud formations using related variables like temperature and humidity. But Schneider’s team says this method underestimates the impact that stratocumulus and other low-lying clouds might have on global temperatures.

In the new study, Schneider his team changed up the climate simulations. Rather than setting the resolution of the simulation based on large-scale dynamics like temperature or humidity as current climate models do, the researchers resolved cloud-scale dynamics. The analysis took months to complete and 2 million core hours–the number of hours to run the simulation multiplied by the number of processor units–of computing. But, in the end, the computationally complex investigation revealed a tipping point for when carbon dioxide levels will shatter these earth-cooling clouds.

Future Forecast

When atmospheric carbon dioxide levels rise above about 1,200 parts per million (ppm), roughly three times today’s levels, the stratocumulus clouds abruptly break up. And if humanity keeps burning fossil fuels at the current rate, Earth should hit 1,200 ppm within a century. The researchers published their findings Monday in the journal Nature Geoscience. Without the shading effect of the clouds, Schneider’s team estimates that global surface temperatures will climb 14 degrees Fahrenheit.

And, once they are gone, stratocumulus clouds may never take shape again. In the researchers’ analysis, the clouds only reformed when CO2 levels dropped below current levels.

The results “point to a blind spot in climate modeling,” Schneider said. “Stratocumulus clouds are important, current models simulate them poorly, and they seemed to have missed the possibility of strong feedbacks from them.”

“We need better models,” he added, and he and colleagues are working to build them.

CATEGORIZED UNDER: Environment, top posts
MORE ABOUT: climate change
  • http://www.mazepath.com/uncleal/EquivPrinFail.pdf Uncle Al

    Carbon dioxide infrared absorption lines saturate passing through vertical 50 meters of atmosphere, If there is any anthropogenic Global Warming (yeah, talk to Wisconsin or Minnesota – or Kansas this winter), its source is black carbon (soot).

    1) Global wildfires, 840 million acres annually;
    2) Chinese brown coal power plants, 993 gigawatts plus 259 gigawatts coming online.
    3) Indian dried cow dung cooking fires..

    Add in planet-wide loudly falsified temperature data. “a blind spot in climate modeling” California has nothing but the Pacific Ocean to its west. Getting a decent 5-day forecast is like finding an Israeli blue 200 shekel banknote idly blowing about a crowded Tel Aviv street. ““a warning shot” for the future” The man-bear-pig wants his cut up front.

    • http://andrewnighswander.com Surreal Estate Agent

      Wow, climate denial and anti-semitism. Wanna throw in a gay slur to really get your boomer blood flowing?

      • http://www.mazepath.com/uncleal/EquivPrinFail.pdf Uncle Al

        HATE FACT: Indisputably true, well-documented by published evidence, never contradicted…and detonating bien pensant academic, political, and feminist skulls.

  • Nom de Plume

    This article is long on claim and short on how, especially since it directly contracts the beloved claim by the AGW faithful that storms will worsen. When you consider that warmer temperatures over water can increase humidity, the how becomes mighty important. Discussing the how is science. Simply running an assertion without the how isn’t.

  • http://www.mazepath.com/uncleal/EquivPrinFail.pdf Uncle Al

    1) DOI:10.1126/science.aax1523
    2) DOI:10.1002/2016MS000765
    3) DOI:10.1029/2018MS001409
    4) BS.
    5) A proposal angering Democrap Socialism while factually excluding refutation triggers incoherent corrupt counterargument and Media censorship.


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