Forget Global Warming, Prepare for New Ice Age, Says Scientist

[F8L]

Originally Posted by Austin50mpg

Ooops My bad.

I will pay more attention next time.

LMAO!

Chogan2, great info as usual. I'll check out the second set after I get home from classes. I have Entomology tonight (6:30-9:30pm) so it's gonna be a loooooong day.

[dogfriend]

oops

[dogfriend]

Originally Posted by F8L

I have Entomology tonight (6:30-9:30pm) so it's gonna be a loooooong day.

3 hours of Bug Science. Better you than me.

[DaveinOlyWA]

posted on news last night...18% increase in CO2 over past YEAR.... also an increase in methane...(a green house gas that is many times more potent) no figures released on the increased levels detected.

so does that mean we break even?

[spf]

Originally Posted by F8L

Unfortunately you have to watch it to the end where they state that greenhouse gasses like CO2 are very important climate drivers and the information on the sun's affect on climate does not change this and in some cases could actually make things worse depending on what kind of solar activity we recieve.

Hey everyone, I know virtually nothing about the science behind global warming, other than it's related to co2. I read something the other day about a "force factor" or "co2 forcing" that is a key factor. Can someone please explain what this is, and is the amount of "forcing" an assumption or has it been proven, or is it a non-issue among global warming advocates and skeptics?

Thanks for your input.

[DaveinOlyWA]

with Earth Day rapidly approaching, it seems that TV has dubbed this week "Earth Week"... besides extra green segments on the "Today Show" and "NBC National News" several cable stations are focusing on environmental topics centering on global warming and climate change.

so a lot of good updated info available. the amount of info is a bit overwhelming, so i have Tivo'd much of it so i can watch it at my leisure.

having already seem a few good shows on the History Channel, its obvious that "Global Change" is what we need to concern ourselves.

for the first time in history, the Earth is changing and not because of what we want it to do, its changing because of what we are not doing.

climate, weather, food, energy are all on precipitous brink of a major change and that direction is not looking good.

[chogan2]

Originally Posted by spf

Hey everyone, I know virtually nothing about the science behind global warming, other than it's related to co2. I read something the other day about a "force factor" or "co2 forcing" that is a key factor. Can someone please explain what this is, and is the amount of "forcing" an assumption or has it been proven, or is it a non-issue among global warming advocates and skeptics?

Thanks for your input.

If you really do know virtually nothing about it, then accept this brief definition, from realclimate.org.

Climate forcings are the changes that affect the energy balance of the planet.

Examples would be changes in greenhouse gas concentrations, in atmospheric aerosols, in the earth's albedo due to (e.g.) changes in ground cover, changes in solar intensity, changes in the earths orbit and inclination (over the very long run), and so on.

If you want a list of forcings considered in most models of short-run climate changes, along with their estimated relative importance, you can look here:

RealClimate

For all intents and purposes, "first order" as used there means "large".

It's a nice article because it focuses you on how subtle all of this is. The imbalance caused by man-made C02 is not huge, in the overall scale of things. It's a small, persistent change. But it's enough to nudge the temperature up, just a bit. And that's enough to change (e.g.) what land is and isn't inhabitable.

If your ultimate question is whether the increased C02 is manmade, the answer is very clearly yes, as had been discussed on several threads here. We have good records on fossil fuel burning, cement production, and deforestation. The total C02 released by those activities, each year, is larger than the increase in the total C02 in the air, each year -- so Nature at present is absorbing, not releasing CO2. We are definitely doing the "forcing" in this area. We have the receipts to prove it.

If the question is, is there agreement on how much temperature rise you'll get out of a given amount of CO2, then the answer is that is some disagreement there, but not a huge amount, as far as I can tell. The estimate is based on both modeling (theory) and comparing the projections to the current data (empirical evidence, though not experiment in the classical sense). From what I read, the level of greenhouse gas increase is sufficient to explain the current increase in temperatures, and that you can't explain the current increase in temperatures by any known factors without including the manmade increase in greenhouse gases. (IE, GHGs are more or less necessary and sufficient to explain the current increase in temperature). Which is what is bizarre about a lot of denialist alternative explanations -- to believe some alternative, you have to forget everything you know about the obvious (the theoretical and apparent empirical impact of C02 and other greenhouse gases). In other words, almost all denialist explanations are incomplete -- they'll put up some theory du jour about something else that is warming the earth, but they never get around to explaining, in addition, why greenhouse gases are not warming the earth, which is what you'd have to have in order to have a complete alternative explanation. Otherwise, you'd get a higher global temperature than we currently have.

Anyway, my reading is that the consensus these days is that doubling atmospheric C02 will eventually lead to 3 degrees centigrade increase in surface temperature, ignoring any further feedbacks (e.g., ignoring the potential for rapid methane release as the permafrost melts, for changes in albedo if we lose the polar ice cap, and so on.) I could be wrong on that but that's the value and the definition that I think I've seen most often. People may reasonably disagree about that. For scale, atmospheric C02 now is about one-third higher now than the pre-industrial-revolution equilibrium.

I don't mean to sound harsh here, but if you actually know quite a lot, and are using this as a seemingly-innocent opening to sow confusion around the difficult topic what, precisely, is and is not a forcing, then I'm done.

[MegansPrius]

And as usual with these sorts of ridiculous claims, Chapman's column was originally published as ...

an opinion column.
Sorry to ruin the fun, but an ice age cometh | The Australian

So as oppossed to peer-reviewed research, he instead publishes in the part of the newspaper that doesn't even require basic fact checking.

And even as recently as 2002, Chapman says:

"Pending a much better understanding of the climate, we should thus encourage and not curb anthropogenic emissions of CO2."

'nuff said.

[spf]

Originally Posted by chogan2

I
If the question is, is there agreement on how much temperature rise you'll get out of a given amount of CO2, then the answer is that is some disagreement there, but not a huge amount, as far as I can tell.
I don't mean to sound harsh here, but if you actually know quite a lot, and are using this as a seemingly-innocent opening to sow confusion around the difficult topic what, precisely, is and is not a forcing, then I'm done.

chogan,

Thanks for your explanation....I really do appreciate it. Yes, what I read was related to do with how much temperature rise you'd get out of a given amount of co2. And no, I really do know very little about the arguments, both pro and con. And, at the risk of sounding defensive, I would not deceptively use this forum or attempt to sow confusion. My ethics and value system are above that, I would hope. I am simply attempting to obtain objective info, do some anaysis, and eventually come to an objective conclusion without bias, preconceived notions, or false assumptions. I'll check out the website.

[chogan2]

Originally Posted by spf

chogan,

Thanks for your explanation....I really do appreciate it. Yes, what I read was related to do with how much temperature rise you'd get out of a given amount of co2. And no, I really do know very little about the arguments, both pro and con. And, at the risk of sounding defensive, I would not deceptively use this forum or attempt to sow confusion. My ethics and value system are above that, I would hope. I am simply attempting to obtain objective info, do some anaysis, and eventually come to an objective conclusion without bias, preconceived notions, or false assumptions. I'll check out the website.

I apologize. Sometimes my paranoid inner economist takes over. As noted earlier in this thread, Realclimate.org is the best place I've seen for reasoned discussion. It's run by climate scientists. And the site Alric brought up earlier in the thread has a nice collection of the key graphs.