LED Christmas lights use just 10 percent of the energy of incandescents, last for some 50,000 hours, and are cooler and safer than older incandescent lights. So why are you hanging onto those old Christmas lights?

Perhaps the best news of all is this: HolidayLEDs.com will take your old lights, recycle them, and give you a coupon for 15 percent off any LED lights they sell. So now you can save money on saving money.

That should make your Yuletide bright.

A recent article in the New Yorker reviews Superfreakonomics, the latest book by Steven Levitt and Stephen Dubner, authors of the best-selling Freakonomics.

Reviewer Elizabeth Kolbert makes the Steves sound like glib amateurs who are simply out of their depth. When they assert the solution to global warming lies at the end of an eighteen-mile-long hose that would shoot sulfur dioxide into the atmosphere, thereby mimicking the cooling effects of a volcanic eruption, Kolbert coolly rips them a new one: "Though climate change is a grave problem, Levitt and Dubner treat it mainly as an opportunity to show how clever they are."

And with a title like SuperFreakonomics: Global Cooling, Patriotic Prostitutes, and Why Suicide Bombers Should Buy Life Insurance, it's hard to believe that the two authors are more interested in serious debate than in provocative soapboxing.

Massive geoengineering projects like the ones they propose have a pathetic track record, and Kolbert delivers a knockout punch to the two econo-hacks: "To be skeptical of climate models and credulous about things like carbon-eating trees and cloudmaking machinery and hoses that shoot sulfur into the sky is to replace a faith in science with a belief in science fiction."

Brava, Kolbert!

I'm inclined to agree with folks who believe it just ain't the holidays without a big ol' Christmas tree hogging all the space in your living room. Putting presents around the Solstice branch doesn't really cut it for me.

Then again, chopping down a beautiful, living tree doesn't seem all that eco-sensitive, either. Is it possible to have a sustainable holiday and a traditional tree? Yes, Virginia, there is such a thing as a green Christmas tree.

There are two reasons I chose a turtle to illustrate this blog post. The first is unhappy news about the fate of Costa Rica's leatherback turtles: As sea temperatures rise due to global climate change, the reefs on which the turtles feed are disappearing. When this threat is added to coastal development, egg poaching and drift net fishing, it becomes apparent that this endangered animal may be extinct within a few years.

The other reason I chose a turtle is to illustrate what's expected at next month's climate talks in Copenhagen: an approach to environmental catastrophe that's incredibly slow to evolve and moves at a sluggish pace. The primary obstacle? The U.S. Congress.

As a result, even more plants and animals may be extinct within a few years. As I've said before, humans are reactive species, not a proactive one, and we'll probably get around to working on climate change after it's too late.

I'm running out of optimism. Anybody have some I can borrow?