Amy from Manhattan: I'll give you the benefit of the doubt and say that you are correct about large-scale vs. small-scale.

But keep in mind that back in the 1970s we were being warned about a coming ice age:

http://www.time.com/time/magazine/article/0,9171,944914,00.html

And as I linked to in my other comment (http://www.dailymail.co.uk/sciencetech/article-2093264/Forget-global-warming--Cycle-25-need-worry-NASA-scientists-right-Thames-freezing-again.html), there is a recent NASA report saying that we may actually be entering an ice age.

The main point in my first comment is that there are many scientists who are skeptical about anthropomorphic causes of global warming—yet we are always told that "every" scientist agrees that it is primarily an anthropomorphic problem and anyone who doesn't agree with that "definitive" finding is a "nut." I've even heard Leonard say that he refuses to have on his show any guest to discuss the skeptical point of view. (And here I thought that Leonard was a tolerant liberal.) I would like to hear debates on the subject. That's all. I don't think that's asking too much.

Sharon from UWS, first, I don't know of any white grass, but if it exists, it must be missing the chlorophyll that not only makes grass (& leaves) green but is essential to the process by which plants *absorb* CO2 out of the atmosphere, so it would be counterproductive to efforts to reduce atmospheric CO2.

To go with Jessie,
I would prefer it if public officials, power executives etc. would stop automatically saying "... because we'll be needing more power capacity in the coming years" whenever they talk about our use. Start by teaching responsible thinking on use.

Gosh, why don't we EVER hear about the far bigger problem, that the purpose everyone shares in "protecting the earth from CO2" is so we can have ever growing uses of energy, and all the impacts on the earth that how we use energy causes.

Without asking the "were are we going" question, all these discussions are just pointlessly failing to ask the "how do we get there" question. Without asking that, these discussions "have no 'there' to go to"

Coal isn't "clean" if it's obtained by mountaintop-removal mining. We need to look at the whole life cycle of the fuel, not just what's produced when it's burned.

Any thoughts on CO2 re-use as in bioreactors, high-intensity green houses, etc?

Given their potency, shouldn't methane emissions be getting more attention?

One of your guests completely dodged that excellent question about whether the population explosion is the real problem. Nations like Japan might indeed have a smaller footprint than the U.S., but the scientist completely avoided the question of whether even a Japanese-level footprint is sustainable. And Mr. Lopate, your dismissive attitude toward that excellent question was regrettable.

I know it was mentioned that painting our roofs white would help reflect sunlight. Might we use white grass or vegetation for our cow pastures as well?

CO2 absorbed by the ocean also has severe effects on aquatic ecosystems, esp. those dependent on corals. But I don't know if that leads to atmospheric effects. I do know that if the ocean is absorbing 50% of emitted CO2, when it reaches the saturation point, the proportion of CO2 absorbed into the air will double. That would be a major atmospheric effect.

OK so how did america get to its 2X overuse statistic?
(In comparison to europe and japan)

Overpopulation. Overpopulation. Overpopulation.

These emperors are so naked.

It's not so much the domestication of cattle that led to the increase of methane as the incorporation of large amounts of meat in the everyday diets of people in the developed world, which didn't become widespread till much later.

Lenard, you had Mr. Gernot Wagner on your show a couple of weeks back. I wonder what your guests think of his idea of including the environmental costs of production in the price of a product?

David (the commenter, not the guest), it's the other way around--it's always easier to predict on the large scale than on the small scale. And weather is not the same as climate.

Let's say we find a way to sequester carbon. Do we run the risk of taking too much out? If so what happens then? This seems to be uncontrollable.

I could live without republican message being substituted for science in these comments.

I find it so amusing. Weather services, with all of their advanced technology, they can't even predict the weather a few hours ahead. Yet they "know" that 50 years from now we'll be living in a tropical climate if we don't cut back on fossil fuel use now. Contrary to what Leonard might believe, there are many scientists who don't believe that climate changes are due primarily to anthropomorphic reason—so where's the public debate on the issue?

"More than 31,000 scientists have signed a petition denying that man is responsible for global warming"

http://www.telegraph.co.uk/news/worldnews/2053842/Scientists-sign-petition-denying-man-made-global-warming.html

Anyone catch this recent news story:

"Forget global warming - it's Cycle 25 we need to worry about (and if NASA scientists are right the Thames will be freezing over again)"

http://www.dailymail.co.uk/sciencetech/article-2093264/Forget-global-warming--Cycle-25-need-worry-NASA-scientists-right-Thames-freezing-again.html