Forget 2 degrees of warming, Hawking says “460”.
Oh, look, there goes another attention-seeking celebrity scientist — flaming out –watch the arc:
In the second episode of his new series “Stephen Hawking’s Favorite Places,” the British physicist warns Earth could soon become as hot as Venus if action to halt climate change is not taken immediately.
Now temperatures on Venus reach 250°C with powerful 300mph winds. Hawking says a greenhouse effect burned the planet’s oceans and lands, and that something similar could happen right here on Earth if climate change continues unabated.
“Next time you meet a climate-change denier, tell them to take a trip to Venus; I will pay the fare,” says the physicist in his show.
Sadly, Hawking is an atmosphere-denier. Venus’s atmosphere is ninety times denser than the Earths. The lapse rate* just goes on and on through 60 kilometers of “air” and Venus ends up with a 467 degree surface, just like Earth would if it had an atmosphere this thick. (See these calculations.)
When Hawking yells “Venus”, I yell back “Mars”. Both have atmospheres of 95% CO2, but one is 467 degrees and the other is minus 40. Hawking may say “but the Martian atmosphere is thin”. I would say “Exactly“! It’s not the percentage of CO2 that matters most, it’s the thickness of the atmosphere.
On Earth, to get the same atmospheric pressure you need to get down about a kilometer below sea-level or 50 kilometers down a mine shaft, which is 40 kilometers deeper than anyone has ever dug.
Hawking can save himself the money for my fare to Venus, and get himself a ticket to Mars. He wants to go to there anyway, so I’m doing him a favour.
Stephen Hawking is supposed to know some physics.
“Venus is like Earth in so many ways,” he explained. “A sort of kissing cousin.”
As I said, when I was a baby-blogger responding to DeSmog: Venus is not much of a twin for Earth:
…Venus is also 40 million kilometers closer to the sun; it spins backwards; a day lasts longer than a year; it has an atmosphere 90 times denser than earth, and it’s hot enough to melt lead on the surface. All this, AND the clouds are made of sulphuric acid.
It’s one hell of a ‘sister’ with acid rain at 475 degrees.
With an atmosphere 90 times denser than Earth, Venus is ‘like’ the earth in the same sense that Bruichladdich Whiskey is ‘like’ water. They’re both clear liquids, but one will sterilize your bench top.
There is something truly tragic about being a physicist that’s ten years behind DeSmog.
* The lapse rate is standard scientific jargon for how much cooler the air gets as we rise up through the atmosphere.
h/t Pat, Geoff.