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Mars Orbiter Sees Changes
pin_gween writes "The long-lived Mars Global Surveyor (8 yrs and flying) has enabled scientists to see changes in the surface of Mars. From the article: 'New gullies that did not exist in mid-2002 have appeared on a Martian sand dune. New impact craters formed since the 1970s suggest changes to age-estimating models. And for three Mars summers in a row, deposits of frozen carbon dioxide near Mars' south pole have shrunk from the previous year's size, suggesting a climate change in progress.' The probe's primary mission ended in 2001 and scientists are hopeful the orbiter's life can be extended for another 5 -10 years."
"I doubt the sun has THAT much influence"
WTF? It's practically the only thing heating up these planets in the first place. What could possibly have more of an impact on global temperatures than the sun?
It is hotter on average on Venus, but not hotter as far as absolute high temperature. Mercury is cooler on average because there is no atmosphere to insulate the side away from the sun, so the ground is exposed to near absolute zero temperature. But on the sun side of the planet, the temperature is much higher.
One 'day' on Mercury is 176 Earth days, so the ground gets a very long exposure (88 days) to a very close sun, followed by a very long exposure (88 days) to deep space. Averaged out, it is cooler than Venus, but the maximum temperature is much higher.
Studies of earth based photos/images and drawings over decades have also suggested the South Polar Cap has been shrinking for a couple of decades. Nice to see the MO data supports this.
Those of us who image and track Mars with amatuer telescopes have known this for quite a long time.
Currently, the North Polar Hood, a blank of clouds that form over the north polar area during the start of the Martian winter has become larger and more complex then any of us have seen going back to the 1950's.
I've just always found it amazing most pro global warming folks toss aside with little worry solar effects. Measuring solar energy output is not very easy and hasn't been done over long periods of time.
Actually we have data of things like argon gas concentration in martian meteorites that allow us to exptrapolate temperatures on Mars and Earth millions of years ago.
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Last time I heard that it was "500 times as much carbon dioxide as one metropolis produces per year".
During the 50s in the UK the rise in refrigerator ownership correlated perfectly with the rise in the crime rate. If correlation equals causation then this close correlation implies that purchasing a refrigerator makes you a criminal (or is it the other way round).
If you're using correlation to demonstrate causation you need to demonstrate the linkage as well. Correlation is never enough.
init 11 - for when you need that edge.
From TFA:After looking at the images, I'd say that the gullies became more prominent, but not that they didn't exist. I can clearly see evidence for the source of the more 'northerly' gully as well as a channel leading to an eroded area in the valley for the more 'southerly' gully.
I agree that the findings are very interesting and important, but to state that the gullies "simply did not exist" is overstating the facts, IMHO.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
Yes; on the back of an envelope (it's a simple calculation). The variation from solar min to solar max would be very small and dwarfed by the changes we've seen on Earth in the past thirty years. Unless you can suggest a mechanism for a sudden solar heating or enlargement, there's not much point to proposing it as an explanation for global warming. And if the solar flux were changing significantly, we'd know--SOHO's a great spacecraft.
They think that sunspot activity affects the temperature of the Earth more than greenhouse gases. Should work the same way on Mars. The Guardian had a little article on it.
Interesting that Pluto is also having unexpected global warming:
n g_021009.html
Global Warming on Pluto Puzzles Scientists
http://www.space.com/scienceastronomy/pluto_warmi
Except that's not a fact. A mere minute with google would have avoided your embarrassment.
?
For Venus
Average temperature: 737 K (464 C)
For Mercury
Average temperature: 440 K (167 C) (590-725 K, sunward side)
737K > 725K so Venus wins.
If they'll still be able to afford fossil fuels in the next century.
You know, fossils are not the only way to get oil to burn and make CO2. You can make it bio and it makes just as much CO2. so does burning wood, trash, or anything else that burns.
Oh, that's not a real problem. CO2 can be extracted from the atmosphere with technical means.
* The atmosphere is big. How do you process millions of cubic kilometers of air ?
* The process, of course, requires energy. Lots of energy.
Its called "plants". You could gain more carbon reduction by irrigation of desert lands (like they have done in southern California) than with any magic machine.
Desalination and irrigation over sections of Africa would do wonders, with only minimum to moderate amounts of energy being used. Likely, you could grow soybeans, extract the oil for biodiesel to power the desalination and irrigation, and have fuel and food left over.
Tequila: It's not just for breakfast anymore!
Of course, part of the problem is that "global warming" started as a political issue. I'm afraid that its scientific roots were fairly weak to begin with and only started to take shape *after* everyone was worked up over the idea.
:-)
I still remember Bush Sr's take on the problem. He told the environmental groups that he would speak with them on global warming as long as they sent him a scientific expert on the problem. As reported by Paul Harvey at the time (as he gleefully pointed out that book stores were hiding their books on Global Warming in the face of one of the coldest winters in the last hundred years), the environmental groups didn't have a scientific expert they could send!
Oops. Talk about egg on your face.
I assume that's a problem that has been corrected, though now you have "experts" on both sides of the issue.
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Note however that if you grow vast stretches of soybeans in an effort to cut down on the carbon in the atmosphere, but then turn around and make biodiesel out of those soybeans, you've accomplished nothing.
OTOH, if you're goal is to reduce the amount of extra carbon in the atmosphere (that was previously trapped in the earths crust), then you have a win (assuming you can make biodiesel without burning regular oil/coal -- which is something we havn't done yet.
The fact of the matter is that it's pretty hard to cut down on the CO2 already in the atmosphere, especially since every car driving person puts _tons_ of extra CO2 out each year. Multiply that by the number of cars on the road and you get an idea of the scale of the problem here.
I read the internet for the articles.
http://volcano.und.edu/vwdocs/Gases/man.html
b s/351387a0.html;jsessionid=47E7825B96884284A97B6E5 C50343A70
Kilauea kicks out only 8,000 tons a day.
http://www.nature.com/nature/journal/v351/n6325/a
Etna kicks out 13+-3Tg/yr, or roughly 1,171,000 US tons of CO2 per year...
Seems like a lot, but, US CO2 production is something a billion tons of CO2 per year. So, the volcanos give out 1/1000 of CO2 as the USA does.
Rock on!
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Apparently, the Earth magnetic field has decreased by 10% in the last 10 years. I'm an electrical engineer and during my studies in sub-atomic physics, I learned that a particles velocity can be effected by magnetic fields. I keep hearing about the increased activity of our Sun and I believe it's possible that more of the Sun's radiation is penetrating the Earth's magnetic field due to it being weaker. If more radiation hits the Earth and the Sun is spewing out more heat, shouldn't that also increase the overall temperature of the Earth and can global warming be attributed to this? I've been bouncing this idea in my head for a while now and I can't see why this MAY not be true.