Summary: The news has become stranger since the climate policy debate has decoupled from the IPCC. Ludicrous claims of certain doom and nightmarish futures splash across the headlines, seldom with rebuttals (climate scientists are complicit in their silence). This one-sided flow of “news” will shape public opinion slowly but surely, creating support for bold measures by President Clinton. Activists are panicking the public for political gain.
“I think looking at grief is quite appropriate, as I believe we are facing human extinction”
— Comment by a reader on the FM website.
“The more immediate danger is runaway climate change. A rise in ocean temperatures will melt the ice caps and cause the release of large amounts of carbon dioxide from the ocean floor. Both effects could make our climate like that of Venus, with a temperature of 250 degrees.”
— Nobel laureate physicist Stephen Hawking on “Good morning Britain on NBC News’ U.K. news partner, ITV News in May 2016.
This was reported as “Earth DOOMED by climate change which could burn us alive, warns Stephen Hawking” by Sean Martin in The Daily Express, 31 May 2016.
We have heard this story before. The BBC hinted at it last year; Hawking has said it before. There is no support for this in the IPCC’s reports and little (perhaps none) in the peer-reviewed literature. There are papers clearly saying the opposite, such as “Low simulated radiation limit for runaway greenhouse climates” by Colin Goldblatt el al, Nature Geoscience, August 2013 — Gated. See the press release here. Excerpt…
“The so-called `hothouse’ climate of the Eocene is the most useful constraint for anthropogenic change. With the solar constant 1% less than today and a few thousand ppmv CO2, the mean temperature was 10 K warmer than today. With CO2 and temperature both higher then than we expect in the foreseeable future, this implies that an anthropogenic runaway greenhouse is unlikely.
“…As the solar constant increases with time, Earth’s future is analogous to Venus’s past. We expect a runaway greenhouse on Earth 1.5 billion years hence if water is the only greenhouse gas, or sooner if there are others.”
While peer-reviewed analysis is good, it is obvious that Earth cannot become Venus in any policy-relevant time. See the NASA fact sheets for Venus and for Earth. They explain that…