So... I've been talking to my students for years about the science of climate change. I've stated as plainly as I can that I'm convinced that emissions of greenhouse gases, in particular CO2, are warming up our planet. To my long-term, whole-planet style of thinking, this is a MUCH bigger issue than something like the war in Iraq. Iraq is "merely" a conflict between two (or a half-dozen) countries. On the other hand, climate change is BIG -- it affects all of the planet's surface (albeit to differing degrees) and it's going to last an unimaginably long time (if all continues along the present trend). The rates at which geologic processes extract CO2 from the atmosphere are way too slow to compensate for the breakneck pace we're generating atmospheric CO2 through the burning of fossil fuels (and forest biomass).

But besides educating students, what am I doing about it? Two days ago, I took a big step towards putting my money where my mouth is. I bought a Toyota Prius, one of the current generation of hybrid vehicles that are much more fuel efficient and produce less greenhouse gases. The Prius is ranked by the EPA as getting 45 miles per gallon in the city and 48 m.p.g. on the highway. It's classified as a partial-zero emissions vehicle.

Here's a comparison for several cars from the EPA's data. Hopefully you can see why I opted for the Prius. Maybe in another five years, there will be a mass-market electric vehicle. That's what I really want for Christmas!

Make and model	Engine	Fuel	Drive	Air pollution score	Fuel-economy (MPG) City/Highway	Greenhouse gas emissions score
Toyota Prius	1.5L 4 cyl	Gasoline	2WD		48 / 45
Honda Civic Hybrid	1.3L 4 cyl	Gasoline	2WD		40 / 45
Honda Insight	1.3L 4 cyl	Gasoline	2WD		45 / 49
Mazda Tribute Hybrid	2.3L 4 cyl	Gasoline	2WD		29 / 27
Lexus LS 600 HL	5L 8 cyl	Gasoline	4WD		20 / 22
Jeep Grand Cherokee	3L 6 cyl	Diesel	4WD		17 / 22
Jeep Grand Cherokee ("flex-fuel")	4.7L 8 cyl	Ethanol Gasoline	4WD		9 / 12 ethanol 14 / 19 gasoline
Hummer H3	3.7L 5 cyl	Gasoline	4WD		14 / 18
Bentley Continental GTC	6L 12 cyl	Gasoline	4WD		10 / 17

Labels: action, global warming, prius, teaching