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Post by walterdnes on Apr 20, 2009 4:54:04 GMT
Solar irradiance doesn't change THAT much during the solar cycle, and sunspots have a so-so correlation with climate. But there hasn't been a working physical theory to connect solar cycles and earth'c climate... until now. See the article at www.sciencedaily.com/releases/2009/04/090409142301.htmIn plain English, the direct cause of heating at the top of the earth's atmosphere is friction between Earth's atmospheric wind and Sol's solar wind. This is a much more direct mechanism than GCRs and cloud formation. Rather than trying to find a correlation between sunspots and temperatures, we should be looking for a correlation between solar wind and temperatures. The past couple of decades have been rather active, solar-wise, and temperatures have gone up. But recently, solar wind has been recorded at the quietest levels in 50 years of data. And this is when temperatures have turned downwards.
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Post by poitsplace on Apr 20, 2009 10:04:50 GMT
Solar irradiance doesn't change THAT much during the solar cycle, and sunspots have a so-so correlation with climate. But there hasn't been a working physical theory to connect solar cycles and earth'c climate... until now. See the article at www.sciencedaily.com/releases/2009/04/090409142301.htmIn plain English, the direct cause of heating at the top of the earth's atmosphere is friction between Earth's atmospheric wind and Sol's solar wind. This is a much more direct mechanism than GCRs and cloud formation. Rather than trying to find a correlation between sunspots and temperatures, we should be looking for a correlation between solar wind and temperatures. The past couple of decades have been rather active, solar-wise, and temperatures have gone up. But recently, solar wind has been recorded at the quietest levels in 50 years of data. And this is when temperatures have turned downwards. I tend to think a lot of that heat is actually from the sun's UV output (although it goes without saying that the solar wind would contribute to that high altitude warming). The sun's UV output varies by quite a bit (more than the TSI change). This affect is then amplified by the expansion or contraction of the atmosphere. Right now the outer edge of the atmosphere has dropped 100miles v/s the measurements during high solar activity. This reduction in the atmosphere's thickness changes earth's capture cross section by more than 2% for UV absorption and possibly the solar wind. On top of that we get TSI changes with an overall drop of .13% solar output. There's also an increase of cosmic rays which may contribute to cloud seeding (the jury is still out on that one). Well, at least that's what I think causes the changes...but I'm no scientist.
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Post by nautonnier on Apr 20, 2009 15:02:10 GMT
Exactly - an - ALL OF THE ABOVE situation.
The problem is that when the Scientists 15 years ago started looking for why things may be getting hotter - they didn't actually know about some of the things that are IN 'the above' to be included.
So the IPCC then built models that replicated what they DID know about, add in a little bias for funding and the directions that were given for the research in the first place - and AGW was born.
Now it could be extremely politically difficult to backtrack if not scientifically.
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wylie
Level 3 Rank
Posts: 129
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Post by wylie on Apr 30, 2009 16:20:36 GMT
I was wondering if these alternative possibilities (below) had been considered and/or rejected as possible amplification factors for the observed warming/cooling observed in SST in time with the solar cycle:
1) Ozone formation as influenced by DUV irradiation (additional greenhouse gas?)
Ozone is formed in the upper atmosphere when atomic oxygen is subject to DUV radiation at a wavelength shorter than 180nm, forming atomic oxygen which reacts with molecular oxygen to form ozone. DUV radiation flux varies much more than TSI over the solar cycle. A recent NASA report mentioned that total UV radiation flux was now 6% lower than at Solar Max. Presumably DUV (the energetic UV that can break the oxygen double bond) variance has an even greater dependence on the solar cycle.
If ozone formation in the stratosphere varies with the solar cycle and since ozone is also a good greenhouse gas (polyatomic) with an absorption band near the peak of Earth's black body emission (~15um?), then presumably it would influence the heat balance in the atmosphere directly (in a similar manner to H2O and CO2) and be dependent on the solar cycle.
Is this a possible candidate for the amplification mechanism? And if not, why not?
2) Oxygen and Ozone (more likely) direct UV absorption of incoming and outgoing UV radiation as affected by the solar cycle
Since UV varies more than TSI over the solar cycle and since both oxygen and ozone absorb UV (at difference wavelengths), could they directly contribute to atmospheric heating? Specifically, as the UV and DUV radiation flux increases at solar max and ozone concentrations are increased by the UV flux, wouldn't UV light that would otherwise be scattered or reflected by ice (or water) be absorbed and heat the atmosphere directly? A significant fraction of UV is scattered back from the surface and the atmosphere of the planet into space. Couldn't some (or a larger fraction) of this scattered/reflected UV that would otherwise not contribute to heating the surface/atmosphere be absorbed (and therefore heat the earth)? There is also a Near IR absorption of O2 (777nm?) that might also be candidate for this kind of direct heating.
3) Expansion of the atmosphere affecting #1 and #2 above
I understand that atmospheric drag on satellites and space debris is lower now because of the solar minimum and because the atmosphere "breathes" (expands during solar max and contracts during solar min). Oxygen (and presumably ozone?) might expand during solar maximum and increase the cross-sectional area of the planet that would intercept UV light (or other wavelengths). Couldn't this also contribute to an amplification of the solar cycle signal?
Any constructive thoughts or suggestions much appreciated.
IWylie
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Post by jimg on May 1, 2009 5:38:52 GMT
My hypothesis is that the reduction of:
- Solar Wind - XUV - X-ray - energetic protons (CME events) - energetic electrons
will cause an increase in heat-loss from the earth.
Perhaps we're focusing too much on if the sun is supplying more or less heat, and not mechanisms in the way the earth loses heat into space.
Since the visible spectrum and UV-A UV-B hasn't changed that much, I don't think that we will see much of a decrease in daytime temps in the short term.
I would suspect that it would be made manifest in the nighttime low temps and winter temps at higher lattitudes.
As the polar regions cool, I would also suspect that this would cause the thermohaline currents to speed up. Perhaps bringing more warm water to the surface for a moderating effect.
If solar energy doesn't pick-up, I think the harsher winters would eventually effect summer temps making them more moderate. (Of course depeding upon where you live.)
Just my 2 cents worth.
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Post by Acolyte on May 1, 2009 10:40:54 GMT
Solar irradiance doesn't change THAT much during the solar cycle, and sunspots have a so-so correlation with climate. But there hasn't been a working physical theory to connect solar cycles and earth'c climate... until now. See the article at www.sciencedaily.com/releases/2009/04/090409142301.htmIn plain English, the direct cause of heating at the top of the earth's atmosphere is friction between Earth's atmospheric wind and Sol's solar wind. This is a much more direct mechanism than GCRs and cloud formation. Rather than trying to find a correlation between sunspots and temperatures, we should be looking for a correlation between solar wind and temperatures. The past couple of decades have been rather active, solar-wise, and temperatures have gone up. But recently, solar wind has been recorded at the quietest levels in 50 years of data. And this is when temperatures have turned downwards. Am I missing something? I thought the solar wind is ionised, so wouldn't that mean the wind never actually comes into contact with the upper atmosphere? There're magnetic fields & radiation belts that I thought are supposed to trap & redirect anything with a charge.
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Post by jimg on May 1, 2009 17:19:30 GMT
Yes, but during higher solar activity, openings in the earth's magnetosphere allows particles to enter. It's also not 100% effective.
In addition, since the magnetic field enters and exits at the poles, there is a pathway there for particles to enter the atmosphere. This gives rise to the auroas. During very energetic events, the auroras can be seen as far south as Florida and Southern Calif.
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Post by nautonnier on May 1, 2009 18:21:03 GMT
My hypothesis is that the reduction of: - Solar Wind - XUV - X-ray - energetic protons (CME events) - energetic electrons will cause an increase in heat-loss from the earth. Perhaps we're focusing too much on if the sun is supplying more or less heat, and not mechanisms in the way the earth loses heat into space. Since the visible spectrum and UV-A UV-B hasn't changed that much, I don't think that we will see much of a decrease in daytime temps in the short term. I would suspect that it would be made manifest in the nighttime low temps and winter temps at higher lattitudes. As the polar regions cool, I would also suspect that this would cause the thermohaline currents to speed up. Perhaps bringing more warm water to the surface for a moderating effect. If solar energy doesn't pick-up, I think the harsher winters would eventually effect summer temps making them more moderate. (Of course depeding upon where you live.) Just my 2 cents worth. The night time temperatures are a very good discriminator as the AGW hypothesis is that the night time temperatures should be higher than normal. The hypothesis that you state above would show night time temperatures lower than expected.
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Post by jimg on May 1, 2009 23:46:41 GMT
Exactly.
I need to brush up on my programming (10 years since I've written non-PLC type programs.
My goal is to plot T-Hi, T-Lo, and delta T.
My thinking is that T-Hi would vary some, T-Lo and Delta T even more so.
We have all seen the trend lines of Ordinary Least Squares plotted from cherry picked points, but I also wonder what an OLS moving average of say 10 years would look like.
I also suspect that the T-lo would vary more at higher lattitudes.
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Post by steve on May 2, 2009 12:36:45 GMT
Atmospheric chemistry is phenomenally complicated and has hardly been represented in previous climate models because the chemistry models are expensive to run and hard to build. As well as effects from anthropogenic changes, solar can also have an impact. This story (the last part, not the first) might be interesting: news.bbc.co.uk/1/hi/sci/tech/7352667.stm
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Post by jimg on May 2, 2009 16:51:12 GMT
Interesting article Steve.
I noted that there were greater changes observed at the poles.
Aqua was launched in 2002, Terra in 1999.
Not a tremendously long period of time to collect data to hang your hat on, but they did get to observe the recent solar max & current solar min.
Although, unless I missed it, that during solar max, there is a much greater flux of ionizing UV & X-ray as well as energetic protons and electrons that also influence the production of HOx and NOx compounds. Not just the cosmic ray flux.
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Post by magellan on May 3, 2009 1:29:06 GMT
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Post by glc on May 3, 2009 10:45:09 GMT
Coincidence?
Not even a coincidence. There appears to be occasions when sea level is driving solar activity.
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Post by nautonnier on May 3, 2009 11:02:10 GMT
Coincidence?Not even a coincidence. There appears to be occasions when sea level is driving solar activity. Your AGW logic is showing
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Post by icefisher on May 3, 2009 12:54:58 GMT
Coincidence?Not even a coincidence. There appears to be occasions when sea level is driving solar activity. Hmmm, interesting. Maybe you should offer the Moana Loa CO2 curve as an alternative explanation and check for coincidence.
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