ShareThis Page

It's the sun, stupid!

| Sunday, July 22, 2007

Go outside at noon on a cloudless day.

Hold up your arm with your palm perpendicular to the blinding bright spot high in the sky.

Feel the heat on your hand• It's coming from 93 million miles away. Yet it's so powerful it'll eventually burn your flesh.

Even filtered by our atmosphere, even after traveling eight minutes at the speed of light, sunshine is so full of energy it can create life on Earth, turn water to gas and melt polar ice.

But the sun can't cause global warming.

The sun is so distant and so small in our sky we forget how enormous it is -- and what a speck of space dust Earth is. Our home star composes 99.82 percent of the mass of the solar system. The sun's mass is 330,000 times the Earth's mass. About 1 million Earths could fit inside the sun.

The sun is a furnace of nuclear fusion beyond human comprehension. Although just an ordinary star, it produces an incomprehensible 386 billion-billion megawatts of energy per second.

Its also real hot. Its core is a hellish 27 million degrees Fahrenheit. Its surface is 11,000 degrees. Its corona, which extends millions of miles into space, has temperatures of 1.8 million degrees.

But the sun doesn't just bathe our tender planet in light and heat. It also blasts us with an invisible hurricane of high-energy electrons and protons that travel at 1.6 million miles per hour.

This solar wind, which extends past Pluto and constantly changes speed, density, direction and magnetic power, can produce auroras like our Northern Lights and knock out electric power grids on Earth's surface.

But the sun can't be causing global warming.

In fact, if you believe the global warming hysterics, the sun's mighty powers to affect our climate have been eclipsed by man's accelerating greenhouse gas output.

The United Nations' Intergovernmental Panel on Climate Change has been saying the sun is responsible for about 10 percent of the roughly 1 degree-Fahrenheit rise in Earth's average temperature over the last century.

But now a new European study of solar activity concludes the sun's effect on global warming is "negligible." Since 1985, the study shows, such factors as sunspots and solar irradiance are trending away from heating the Earth.

The Royal Society, the United Kingdom's national science academy, pronounced that this new study "comprehensively" disproves claims that the cause of recent global warming is increased solar activity. Humans are to blame. Natch.

Lots of other studies have come to the opposite conclusion, of course.

Going back 10,000 years, a 1998 study found that past periods of global warming coincided nicely with increased sunspot activity, which occur during increases in the sun's brightness and energy output. In 2004, a study by the Max Planck Institute for Solar System Research said Earth was getting hotter because the sun was burning brighter than it had in 1,000 years.

We don't want to get into an ugly debate about the prime cause of global warming. But maybe all those sun-worshipping ancestors of ours were not such dummies after all.

Sure, they lived in caves, thought gods controlled the weather and couldn't even spell SUV. But eons ago they figured out what should still be obvious to every creature on Earth today.

The mighty sun is in charge of what happens on puny Earth -- not humans or their fires.

TribLIVE commenting policy

You are solely responsible for your comments and by using you agree to our Terms of Service.

We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.

While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.

We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers

We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.

We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.

We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.

We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.