Louisville Mojo: Solar Influences on Climate Change

There are few climate change myths that grab my attention more than the idea that fluctuations in natural solar cycles are the cause for the general warming of the Earth's surface over the past 100 years. Basically the idea is this: there are natural cycles that bring us closer to the sun and natural increases in solar activity that both increase the Earth's temperature.

Now, I am not going to argue that the sun has nothing to do with the climate. Of course is does, but the data shows that there has been no trend in solar activity that can account for the increase in temperature we have had, and the data is really good on this point. There are other methods of scientific data collection that can be argued as too small a sample or unproven, but we have been recording data from the suns activities for decades using both space and land based technologies which have not been controversial.

For starters, here is an interesting fact. If changes in our relationship to the sun, or if the sun intensifying in some way, was the cause of this overall warming you would expect to see an increase in temperature in all layers of the atmosphere pretty much uniformly. It is like if you put a glass of milk close to a heat lamp. You would expect the whole thing to heat up.

Well, what is happening is the lowest layer, the troposphere, is warming while the upper part of the atmosphere, the stratosphere, is cooling. Not quite what you would expect, right? This lines up clearly with the green house effect. The carbon dioxide we put in the atmosphere stays mostly in the troposphere, trapping radiated heat which causes two things. One, in trapping the heat it warms up the troposphere and second it keeps the heat from getting to the stratosphere, which reduces its temperature. Simple, right? But there's more.

If the sun was responsible for the overall warming of the Earth then why is it heating up at the same rate at night as it is during the day? The sun hits the Earth's surface in the day time, so shouldn't it be warming up the Earth more when it is day time and then cooling when it's night time? Once again, this can be explained by the green house effect which keeps the heat normally put off by the Earth's surface at night from escaping the atmosphere.

Oh, and another interesting point. It is warming more in the winter than in summer. Winter means snow and ice in a great portion of the world, right? Well, snow and ice reflect the sun's rays, which should keep an increase in the sun's effect from having much impact. It's like the reflective board you put in your car window to keep it from heating up. The deal is the rays that are deflected get trapped by green house gases instead of escaping back into space. This causes a heating of the air, which leads to a decrease in ice and snow pact, further decreasing the Earth's ability to regulate its temperature and a marked increase in temperature during the winter.

But let's get back to the data. If you look at the data from NASA and BRI you can see that even though there are cyclical fluctuations in solar activity there is an irrefutable overall increase in global surface temperature. Ah, but what about the “The Great Global Warming Swindle”, a movie that supposedly uses this same data to disprove global warming? For one, the graph they point to only looks at sun spot cycles, and two they stop the graph at 1975. You know why they stop the graph there? It is not because they don't have the data. It is because past that point there is no correlation. The line that shows global temperature actually shoots up while the sun spot activity goes sharply down. This is called “cherry-picking”. When someone wants to use data to mislead you they choose only to show you the parts that support their claim, not the whole set that shows a completely different picture. I've included a picture of that very graph with the data added in.

So what's the moral of the story? Anytime you are reading an article, even if it supports your preconceived notions, you should look at the root data and reports they cite. Who knows, you might learn something. That's got to be worth something.

I will leave you with some quotes from NASA and the Navy:
The Sun “Contributes, if anything, a very slight overall cooling in the last 25 years.” And “None of the natural processes can account for the overall warming trend in global surface temperatures.”

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Louisville Grows sat nov 14 2009 at 12:51 am ·


	I'd be remiss if I didn't say where the photo came from. It's also probably the best place I've seen for unbiased, fact based, climate change denier rebuttals. Enjoy. http://www.youtube.com/user/greenman3610

EdenSprings mon nov 16 2009 at 3:40 pm ·


	Hmmm....Is it just me, or does that spike in global warming start right about the time Abramson became Mayor?

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