Global warming (part 2)

Posted by Daniel Pendick
on Thursday, April 5, 2007

Skepticism thrives in a climate of uncertainty. Without the definitive proof to establish the facts of a question, anyone can float a hypothesis — however strained and baseless — and simply say, "Prove I'm wrong."

Last week, I wrote about the idea circulating in the blogosphere that warming on Mars and several other celestial bodies points to a solar-system-wide climate trend driven ultimately by an increase in the Sun's output. Mars has been singled out for particular attention.

Today in the journal Nature, researcher Lori Fenton from the NASA Ames Research Center in California reports she thinks she knows why Mars' frozen south pole is stuck on defrost. Fenton compared maps of Mars' albedo, or brightness, taken by the Viking orbiters in 1976–1978 to similar maps created from Mars Global Surveyor data collected in 1999–2000.

Mars looks darker, indicating that wind has scoured away light-colored dust from the darker rock below. The darker surface has been soaking up more solar radiation and warming the atmosphere. This stirs up winds that scour even more dust away, creating a positive feedback. A computer model of the martian atmosphere suggests Mars has warmed 0.65º C over the 2-decade period Fenton studied. The model also suggests the warming could eventually trigger a global dust storm and "reboot" the planet's albedo back to an earlier, cooler state.

Or maybe Fenton is totally wrong. It's just ONE study. But doesn't it feel good to hear about someone trying to solve a climate-change question using real data and rigorous scientific methodology as opposed to unsupported opinions fueled by political agendas?

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