16.2.09

Hoax-Watch: What's the Sun got to do with it?

In my travels around the internet, I've had some exhausting conversations with climate change deniers regarding the impact of the sun on climate. So let's be clear.

The sun drives our climate, without question. Everything we see around us (and a great amount that we don't) related to meteorology, ecosystems, climate, hell, urban planning; it all relies on the sun (whose name is Sol - fun fact of the day!).

In fact, through one way or another, the sun is responsible for all electricity generation, with two exceptions - nuclear and geothermal (though you could make a really convoluted case for geothermal). All other cases, solar (duh), wind, hydro-electric depend on the sun one way or another. Hell, even fossil fuels - the sun provided the energy that ancient forests locked away in the form of carbon, which fossilized over time.

So the sun is important.

But is it driving the warming we've seen lately?

In a word: no.

In two words: Definitely not.

First, background. I've heard this whole sun-not-human cause thing before, but for this post I wanted someone I could point at to say that they're wrong. One of them we already know - Professor Jan Veizer believes the sun is responsible for global warming. But with the help of trusty google (which is really all you need), I Felt Lucky and found the post The Sun Also Sets at a blog thoughtfully named globalwarminghoax.wordpress.com. How nice!

They posted an article from Investor's Business Daily, which I'm not sure I place a lot of trust in for my climate-related news - but at least they quote some kind of scientific study. Although, reading a bit further, I lost that trust pretty quickly. Here's a quote:

“The effects of solar activity and volcanoes are impossible to miss. Temperatures fluctuated exactly as expected, and the pattern was so clear that, statistically, the odds of the correlation existing by chance were one in 100,” according to Hoover fellow Bruce Berkowitz.

The study says that “try as we might, we simply could not find any relationship between industrial activity, energy consumption and changes in global temperatures.”
Well, sorry Bruce, but the rest of the world's scientists have!

I'll address the actual science in a second, but I just have to heap some more scorn on this. I'm a little sorry to keep bringing up the IPCC's reports, but apparently people keep not reading them, so hey, whatever. The latest Intergovernmental Panel on Climate Change's report says that there's no doubt, human industrial activity responsible, blah blah blah. I swear I keep repeating myself.

So let's look at this sun-centered idea a little closer.

There are three ways that scientists think the sun could affect the shift we're seeing in the Earth's climate.

First, the strangest one. The sun is powerfully magnetic, but that magnetism waxes and wanes over time depending on output (a little bit, anyway). Now, forget that for a second; there are these things called cosmic rays. They come from a lot of different sources, including the sun, neutron stars (look them up they're cool), black holes, active galaxies, and all sorts of astronomical things. Essentially, they're radiation - atomic stuff flying through space - but they're strange because they have so much energy behind 'em. When cosmic rays hit the atmosphere, they do strange things, and there's a chance that one of those things is giving water vapor an extra kick towards becoming a cloud to form. So, the theory goes, cosmic rays may encourage cloud growth, the clouds would reflect sunlight, and the Earth would cool. So a lack of cosmic rays would mean less clouds, more sunlight hitting land or water, and warmer temperatures.

Still with me?

The interesting thing is that the sun's magnetic field can mess up cosmic rays. And the magnetic field varies. So, if the magnetic field is varying the right way and preventing cosmic rays from reaching us, that could mean fewer clouds due to cosmic rays and warmer temperatures. And hey, we're seeing warmer temperatures!

The big problem here? No one really understands how this whole cosmic ray = cloud thing works; current research hasn't generated anything definite. And worse, while models have found some relationships between cosmic rays and temperature in the past, all of that breaks down in the last 30 years - because humanity's carbon emissions are starting to overwhelm natural systems.

This is a point I'm gonna keep coming back to. The Earth's climate varies naturally. That does not mean we can't influence it. We are influencing it. And we're doing it at such speed that we're overwhelming the natural stuff. Natural shifts take so much longer than what we're seeing happening right now.

Okay, second theory: sunspots. These are dark spots on the sun (and may also reflect how many cosmic rays the sun does or does not swallow up). More directly, though, they influence how bright the sun is. So, lots of sunspots equal dimmer sun; fewer sunspots equal brighter sun, and therefore warmer Earth. Right?

Except that sunspots work on an 11-year cycle, generally (that's just the way the sun works). Furthermore, astronomers have been keeping tabs on the level of sunspots since the 19th century. The simple fact is that sunspots and Earthly temperatures don't add up.

The third theory is that the sun might just be a little brighter. We don't really know what the sun does, on a grand scale - we've observed a lot of cycles, but we don't truly understand them (the same way we don't truly understand the climate).

People point to Mars. And, truth be told, the Martian ice caps have been melting lately (ironically, the ice caps are crusted over with frozen carbon dioxide - dry ice). To be more accurate, they've been melting for a couple Martian years (about two years), and that's all the data we have.

There are other examples of stuff going on in the solar system. Jupiter's storm systems are changing. Pluto is getting hotter despite moving away from the sun. There's a hot spot at one of Saturn's poles.

But here's the thing, y'all: these are planets, not thermometers. Now, if we had a research team on Mars, measuring the ice, measuring them again, figuring out exactly what makes up the atmosphere, creating climate models, etc. - that might be something. But to say that the Martian ice caps shrinking a bit over the course of no more than three Martian years must mean that climate change on Earth is caused by the sun - that's reaching. Mars has a climate all its own - and that climate is every bit as complex as Earth's. (In fact, in the case of Jupiter and Saturn, their climates are probably much, much more complex.)

It's cherry-picking examples. We are on the Earth. We have satellites in orbit, measuring solar activity. We have reliable records of sunspot data for the last 130-or-so years. We have thousands upon thousands of scientists experimenting, modeling, and writing papers that lead to scientific consensus on climate change. And all evidence suggests that the sun is not responsible.

But when a NASA satellite takes a few pictures and measurements, that suddenly absolves humanity of any responsibility for their actions?

I'm not saying NASA doesn't matter. Hell, I'm not even saying the sun doesn't matter. But these leaps that are being made boggle the mind - and confuse people. You cannot directly compare the Earth and Mars; Mars has a different kind of orbit, atmosphere, and composition. You cannot compare the Earth and a gas giant for the above reasons. And there's no way in hell you can compare the Earth and Pluto - which isn't even a planet, because it's so much like an asteroid.

We shouldn't stop studying other planets. But we need to remember that they are what they are, and despite all the effort that's gone into understanding the Earth, we still don't understand its climate beyond broad predictions. So until we understand other planets (or the sun) better than we understand our own home, can we lay off the ignorant caused-by-the-sun nonsense?

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