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Global Temperatures are Expected to Rise by 4°C by 2100

Global Temperatures are Expected to Rise by 4°C by 2100

According to a Dec. 31 news release from the University of New South Wales, global temperatures are expected to rise by 4°C by 2100 if carbon dioxide emissions are not scaled back. Researchers also say that the continued increase in global average temperatures will result in an additional 4°c by 2200.

Global Temperatures are Expected to Rise

Image Courtesy of WIkipedia

The findings are published in a recent article in the journal Nature, and may explain one of the great unknowns of climate sensitivity: the role of cloud formation and whether this will have a negative or positive effect on overall global climate change.

“Our research has shown climate models indicating a low temperature response to a doubling of carbon dioxide from preindustrial times are not reproducing the correct processes that lead to cloud formation,” said Steven Sherwood, a professor from the University of New South Wales’ Centre of Excellence for Climate System Science.  “When the processes are correct in the climate models the level of climate sensitivity is far higher.  Previously, estimates of the sensitivity of global temperature to a doubling of carbon dioxide ranged from 1.5°C to 5°C.  This new research takes away the lower end of climate sensitivity estimates, meaning that global average temperatures will increase by 3°C to 5°C with a doubling of carbon dioxide.”

The key to this narrower – albeit much higher – estimate is found in the real observations around the role of water vapor in cloud formation per Science Recorder.

Observations show when water vapor is taken up by the atmosphere due to evaporation, the updrafts can either rise to from 15km to just a few kilometers to form clouds that produce heavy rains before falling back to the surface without forming rain clouds.

The researchers uncovered that climate models that show a low global temperature response to carbon dioxide do not include enough of this lower-level water vapor process. In its place, they simulate all updrafts rising to 15km and forming clouds.

The result is such that, when water vapor processes are correctly represented, the sensitivity of the climate to a doubling of carbon dioxide means Global Temperatures are expected to rise by at least 4°C by 2100.

About Chelsea Alves

  • brunsk42

    Sounds like a scam to extort money, the proof is that temps have been declining and have not risen in over 15 years.. There is also much more ice covering the continent than they lead you to believe..

  • proudrat


  • proudrat

    So now that prediction you made in the 90’s are not happening you just make new predictions…..I see how this scam works.

  • rhjames

    I’m a graduate of UNSW, but I’m ashamed to see rubbish like this associated with it. Cloud density and area is probably one of the biggest influences in our climate, yet even the IPCC states that it’s poorly understood. Higher temperature means higher humidity, so more cloud, and self regulating cooling. There’s no evidence to suggest otherwise. Scientists need to stop this alarmist nonsense, just to get research funds, and be honest with us.

  • rhjames

    If this theory is valid, why has there been no warming for at least the past 17 years? This is alarmist nonsense.