Runaway greenhouse effect turned Venus into oven, scientists sayScience | 207786 hits | Nov 28 2:29 pm | Posted by: Winnipegger  The first data from the planetary probe Venus Express is helping scientists shape the story of how a young planet with everything needed to support life became instead a sulphurous, baking hell.Commentsview comments in forum Page 1 You need to be a member of CKA and be logged into the site, to comment on news. |
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I noticed that one of the gasses found in the upper atmosphere of Venus is hydrogen fluoride. There's also sulphur dioxide and the clouds have sulphuric acid. One of the greenhouse gasses targeted by the Kyoto Accord is sulphur hexafluoride, which is 22,000 times as powerful a greenhouse gas as the same mass of carbon dioxide. I therefore speculate there may be SF6 on Venus. In fact, SF6 will decompose at about 500�C here on Earth, and at a lower temperature at higher pressure. When it decomposes it absorbs energy, in fact it's a powerful refrigerant. Pressure on the surface of Venus is 92 bars; Earth is 1.01325 bars so Venus is 90 times as much. Decomposition of SF6 in the lower atmosphere of Venus would occur at something cooler than 500�C. Temperature on the surface of Venus varies with weather and the equator is hotter than the poles, but it's about 450�C. That means it's about right for decomposition of SF6. In fact, SF6 may trap heat in causing it to heat dramatically until decomposition temperature is reached, then act as a refrigerant to prevent the temperature from rising above that. This would mean SF6is actively regulating the temperature.
Venus has a day much longer than Earth, in fact it's day is longer than it's year, so if SF6 doesn't have any sunlight to trap night temperatures may be significantly cooler. That's exactly what Venus Express reported today. The day/night temperature difference is greater than they expected. But then they thought Venus high temperature was caused by CO2. The presence of SF6 may account for this.
Previous probes didn't have instruments to detect SF6, but Venus Express does. Venus Express was built by the European Space Agency and is currently in orbit around Mars. I sent an email to ESA asking them to look for SF6, but didn't get an acknowledgment. Hopefully one of the scientists will look.
So CO2 isn't heating Venus either....What's their excuse for Mars frigidity?
I guess they don't have computer models for venus or it would be CO2 as well.
... You see, back in those days, rich men would ride around in Zeppelins, dropping coins on people, and one day I seen J. D. Rockefeller flying by. So I run of the house with a big washtub and� hey! Where are you going?
... Anyway, about my washtub. I�d just used it that morning to wash my turkey, which in those days was known as... a walking bird. We'd always have walking bird on Thanksgiving with all the trimmings: cranberries, injun eyes, yams stuffed with gunpowder. Then we'd all watch football, which in those days was called "baseball"...like the time I caught the ferry over to Shelbyville. I needed a new heel for my shoe, so, I decided to go to Morganville, which is what they called Shelbyville in those days. So I tied an onion to my belt, which was the style at the time. Now, to take the ferry cost a nickel, and in those days, nickels had pictures of bumblebees on �em. �Give me five bees for a quarter,� you�d say.
Now where were we? Oh yeah - the important thing was I had an onion on my belt, which was the style at the time. They didn�t have white onions because of the war. The only thing you could get was those big yellow ones...
This is important because the whole "global warming" thing came from studies of Venus. If we see Venus has a strong effect from something that isn't CO2, perhaps the Global Warming guys here will lay off the CO2 arguments.
Remember, CO2 is scrubbed out of the atmosphere by trees. Perfluorocarbons (PFCs) and hydrofluorocarbons (HFCs) are thousands of times as powerful as CO2. The Kyoto Accord restricted emissions of 6 gasses, and their Global Warming Potentials:
CO2 (1)
methane (23)
nitrous oxide (296)
PFC (varies from 5,700 to 11,900)
HFC (varies from 120 to 12,000)
SF6 (22,200)
The Global Warming Potential comes form the 2001 Intergovernmental Panel on Climate Change (IPCC). For example, 1 tonne of methane will warm the Earth as much as 23 tonnes of CO2.
PFC and HFC were used to replace CFC, since CFC releases chlorine when it breaks down. Chlorine destroys ozone. Each of these is a group of chemicals, not a single chemical; its GWP depends on which chemical you're talking about. PFC is made of just carbon and fluorine; HFC is hydrogen, carbon and fluorine. But all these fluorocarbons are thousands of times more powerful greenhouse gasses than CO2. One use of these things is propellant for aerosol spray cans. It's better to use an air pump to spray paint rather than an aerosol can. Another use is refrigerant and air conditioners. That's why service technicians are now required to capture old refrigerant, not just vent it. The Kyoto Accord did address all greenhouse gasses, but the media likes to simplify everything, they obsess about carbon.
ridenrain, your reply shows you have great difficulty following the article. Scientists feel discovery of new knowledge is "the thing", messing around with practical product development is menial, and politics or military are just way beneath them. This sort of new discovery is what they live for. A few other people actually enjoy this sort of discovery; it's a lot better than the latest petty accusation from our politicians in Ottawa.
That effect is at odds with the intent of a second treaty, drawn up in Kyoto, Japan, in 1997 by the same countries behind the Montreal pact.
In fact, the volume of greenhouse gases created as a result of the Montreal agreement's phaseout of CFCs is two times to three times the amount of global-warming carbon dioxide the Kyoto agreement is supposed to eliminate.
Seems like the Kyoto crowd did not do their homework.
... You see, back in those days, rich men would ride around in Zeppelins, dropping coins on people, and one day I seen J. D. Rockefeller flying by. So I run of the house with a big washtub and� hey! Where are you going?
... Anyway, about my washtub. I�d just used it that morning to wash my turkey, which in those days was known as... a walking bird. We'd always have walking bird on Thanksgiving with all the trimmings: cranberries, injun eyes, yams stuffed with gunpowder. Then we'd all watch football, which in those days was called "baseball"...like the time I caught the ferry over to Shelbyville. I needed a new heel for my shoe, so, I decided to go to Morganville, which is what they called Shelbyville in those days. So I tied an onion to my belt, which was the style at the time. Now, to take the ferry cost a nickel, and in those days, nickels had pictures of bumblebees on �em. �Give me five bees for a quarter,� you�d say.
Now where were we? Oh yeah - the important thing was I had an onion on my belt, which was the style at the time. They didn�t have white onions because of the war. The only thing you could get was those big yellow ones...
sulphur hexafluoride....HMMMMMM.....not CO2......HMMMM
So CO2 isn't heating Venus either....What's their excuse for Mars frigidity?
I guess they don't have computer models for venus or it would be CO2 as well.
Based on the pressure difference alone, there'd be over 15,000 times more CO2 in a given volume of 'air' on Venus than Mars.
edit: fixed math.
The ozone layer protects earth from the "runaway greenhouse effect" and has done so for billions of years.
Besides on earth we have negative not positive feedback as well. That in itself should definitely prevent "runaway greenhouse bandwagons".
In 1.5 billion years the sun will become a super nova, boil the oceans away and end up a white dwarf.
Carbon credits won't help.
sulphur hexafluoride....HMMMMMM.....not CO2......HMMMM
So CO2 isn't heating Venus either....What's their excuse for Mars frigidity?
I guess they don't have computer models for venus or it would be CO2 as well.
Based on the pressure difference alone, there'd be over 15,000 times more CO2 in a given volume of 'air' on Venus than Mars.
edit: fixed math.
And as absorption is directly proportional to density:
dI_l=-k_lpI_lds (pretend the ls are lambdas)
That means that the atmosphere of Venus absorbs CO2 15000 times faster. It's not the percentage of CO2, it's the absolute amount.
PS: Thanks, Blue, for the excuse to dig out my old astrophysics text!