By Marty Russell
What do you think Curiosity, the NASA rover that made a flawless landing on Mars early Monday morning despite any number of things that could have gone wrong, will find in its exploration of the Red Planet? Little green men? Beautiful, scantily-clad Martian princesses? Mitt Romney’s tax returns?
Maybe a warning. Not a sign that reads, “Earthlings Go Home!” but perhaps a paraphrase of one of those billboards you see outside new subdivision developments in big cities that says, “If you’re not careful you’d be home right now.”
The debate still rages over global warming here on Earth although you can’t ignore the more than 4,000 record temperatures set around the country in July alone or the current widespread drought conditions and melting of polar ice. Some would prefer to see it as just a phase, a cycle the planet is going through while some of us believe that’s a lot like telling the dinosaurs don’t worry about that asteroid, everything will be back to normal in a few million years.
If you want to see the effects of real global warming, you don’t have to look any further than our sister planet Mars. Once a warm, wet planet with oceans and rivers whose beds still crisscross the Martian landscape, it’s now cold and dead and the only water we’ve found thus far is frozen in its polar ice caps.
While scientists agree that global warming killed Mars and could do the same thing here on Earth, how it happened differs. On Mars, it was likely the result of several asteroid impacts that heated the surface of the planet to the point where convection from its core slowed down. That convection, just as here on Earth, is what drives a planet’s magnetic field which shields it from harmful radiation from the sun.
About four million years ago, Mars lost most of its protective magnetic field. Today it is miniscule compared to Earth’s, which covers the entire globe. Think of Earth’s magnetic field as one of those huge electromagnets junkyards use to pick up smashed cars. By comparison, Mar’s is more like a refrigerator magnet today.
The loss of its magnetic field allowed the surface of Mars to heat up, evaporating all the water and allowing most of its atmosphere to escape into space. Here on Earth, the same thing appears to be happening with the depletion of our protective ozone layer, which serves pretty much the same purpose, protecting us from the sun.
So if global warming is real and we do nothing to stop it, Earth one day could very well look like Mars and someone from another planet wouldn’t even have to send a rover here to find out why. They’d probably be able to see enough dead hulks of carbon-spewing cars and factories from orbit to figure it out.
Marty Russell writes a Wednesday column for the Daily Journal. He can be reached at firstname.lastname@example.org.