Study discovers why global warming will accelerate as CO2 levels rise

Study discovers why global warming will accelerate as CO2 levels rise
Credit: University of Reading

Global warming is likely to speed up as the Earth becomes increasingly more sensitive to atmospheric CO₂ concentrations, scientists from the University of Reading have warned.

In a new study, published this week in the prestigious journal PNAS, the scientists explain that the influence of increasing levels of atmospheric CO2 on will become more severe over time because the patterns of warming of the Earth's will lead to reduced cloud cover in some sensitive regions and less heat being able to escape into space.

The findings are supported by observations, suggesting that forecasts made by climate models evaluated by the Intergovernmental Panel on Climate Change are realistic.

Paulo Ceppi, researcher at the University of Reading and lead author of the study, said: "This resemblance of computer simulations to observations increases our confidence in projections that the climate sensitivity to the progressive rise in will increase over time into the future."

Evidence suggests that the upper level of the Earth's atmosphere warms faster than the surface in response to CO2 levels. However, the new study shows that as CO2 levels increase further, the rate of warming in the upper levels slows in comparison with that closer to the Earth's surface.

Reduced contrast in temperature between the upper and lower levels of the atmosphere causes decreased low altitude cloud cover over some areas of the Earth's oceans, leading to more sunlight reaching the sea surface, and therefore a more rapid rise in .

These conditions also impede the loss of heat from the atmosphere into space, contributing to the accelerated surface warming in response to rising CO2 concentrations.

These results emphasise the importance of rapidly reducing human caused emissions of greenhouse gases to avoid the worst impacts from ongoing as discussed at the recent COP23 meeting in Bonn that builds upon the 2017 Paris climate agreement.


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More information: Paulo Ceppi et al. Relationship of tropospheric stability to climate sensitivity and Earth's observed radiation budget, Proceedings of the National Academy of Sciences (2017). DOI: 10.1073/pnas.1714308114
Citation: Study discovers why global warming will accelerate as CO2 levels rise (2017, November 29) retrieved 20 August 2019 from https://phys.org/news/2017-11-global-co2.html
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Nov 29, 2017
How is this a new explanation. It is a new study, but same theory that i learned in grade school

Nov 29, 2017
The findings are supported by observations, suggesting that forecasts made by climate models evaluated by the Intergovernmental Panel on Climate Change are realistic.

Uh huh. Suuure they are.

And back on planet reality, there are no observations that show a trend of decreased cloud cover over the oceans. So all the claims are based on computer manipulated climate models which have not been verified against observations. Science: 1 Alarmist climate study: 0

Refer to the latest (2013) report from IPCC. Look at the chapter on "Observations". Nothing on reduced cloud cover over the oceans.

Nov 29, 2017
Ok. now i know this AGW is total BS insanity , just go look at Monthy Avg charts back as far as u can [if you can find them ] You may have to plot a few yourself and only white countries have them, BOM in aus are the easiest , Canada u have to compare month to month. pick any location , NO HOCKEY STICKs R SEEN ! all look flat .

Nov 29, 2017
On second thought, I'll do the work for you so you don't have to. But you can verify it yourself in the IPCC AR5 report (2013), Chapter 2, Observations: Atmosphere and Surface, section 2.5.6 Clouds (p. 208):

http://www.ipcc.c...ex.shtml

Satellite observations of low-level marine clouds suggest no long-term trends in cloud liquid water path or optical properties (O'Dell et al., 2008; Rausch et al., 2010).

And
there remains substantial ambiguity regarding global-scale cloud variations and trends, especially from satellite observations

You're welcome.


Nov 29, 2017
Oh, and one more thing. Here's how realistic the IPCC found the models in 2013, from the Fifth Assessment Report:

https://www.ipcc....S-14.jpg

That black line below all the squiggly colored lines represents global temperature observations. The squiggly lines above are the range of temperatures predicted by several models. They all predict much more warming than has been observed.

Accuracy of climate models as shown by the IPCC? Not accurate. QED

Dec 06, 2017
How is this a new explanation. It is a new study, but same theory that i learned in grade school


Yeah, it's not. It's just more evidence supporting the current model.

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