Glacification of the North America at 3million years (my) before present (BP) was a known fact.

No past research noted a sharp drop in CO2 level. It was almost constantly dropping since 150my BP.
http://www.geocraft.com/WVFossils/Carboniferous_climate.html

I thought the old theory was that the formation of the Isthmus of Panama by continental drift brought about a change in ocean circulation reaching the arctic ocean resulting in the glacification. This looks to me like a better explanation then the sudden drop in CO2 level which is a non-event.

http://commons.wikimedia.org/wiki/Image:65_Myr_Climate_Change.png

The climate and ice models say so - it must be true.

Southern Greenland is approximately at the same latitude as Scandanvia. It is the climate produced from prevailing winds that keep Scandanvia warmer and Greenland cooler.

However, with more CO2 in the atmosphere, there will be more warming all the way around.

No good estimate as to how long it will take for Greenland to melt, but it probably won't be in our lifetimes. However, Greenland is so large that it's presenese impacts the climate itself as it preturbs the jet stream and produces a lot more storminess that there would be other wise. So, when Greenland does melt, there will be a significant shift of climates. Much more desert like in North America.

Well, this is of no logic.
Even myself, not being a global warming skeptic, think that there is much absurd logic in this news.

The "only" thing to make Greenland freezing is "solely" a drop in CO2?
No, I don't buy into it.
What if there was some change in solar output, some unknown change in oceanic circulation, some change in cosmic rays or some small polar shift

Scientists sometimes are too narrow and absurd.
I start doubting the global warming thing, even when seeing the poles melting I remain open to whatever it may be, who knows for sure what is the cause for global warming. However I do know that pollution by oil and coal is never good.

Regarding climate researchers and CO2:

When your only tool is a hammer, everything looks like a nail.

This is really getting funny, as in stupid funny. Show me the signature of today's CO2 greenhouse gas hoax ... It should be there.

It's quite possible that Greenland was ice free 3 million years ago because the Earth's climate was a lot warmer. Were you driving around in your SUV 3 million years ago? No, so what caused the warming?

Why did the ice ages start some 3 million years ago? Who did that.

My money is on the sun driving Earth's climate.

I wonder what the effect of the earth's higher core temperature is on the ice sheet and global warming generally?

My specific questions would be as follows:

Why is the earth's core warmer than the surface? (residual heat from the big bang, nuclear reactions, etc.?)

To what part of the earth's surface temperature does core heat contribute?

Is the earth's core cooling? If so, at what rate?

Could the cooling have passed a threshold that allowed the ice sheet to form?

What is the implication of further core cooling on global warming (or cooling)?

I can't believe how someone can get away with making such a stupid statement as "the ONLY thing that can explain the transition from an ice free Greenland is a drop in CO2 etc..." The ONLY THING? Really? What about every other TRUE aspect of what causes climate change like perhaps the SUN! or changes in ocean currents, Changes in the earth's axis or orbit. But NOOO it must be CO2. the less then 1% of our atmospheric gas which is very debatable if it causes warming at all! but to totally disregard and not mention methane or water vapor KNOWN causes of warming and to solely blame CO2 is very insulting to me and should be also to anyone with half a brain or the slightest knowledge of anything weather and climate related. I am just sick and tired of every temporary warming episode being blamed on CO2. To add insult to injury is the mention of ice sheet and climate modeling, these models are barely if at all acurate to predict what could happen in a few months, but can miraculously know what happened 3 million years ago!

OK, seriously, do these "State of the Art" researchers really think they have solved the puzzle?

Does anyone think it a just a bit ODD that the study magically determines that it is "just about" the CO2 levels of present that existed when Greenland was ice free? And, more importantly, that lower CO2 levels made the ice form?

As a famed SNL character might say "How Conveeeenient!"

You see, anything else might just poke a hole in the AGW agenda.

And while there are lots of interesting ideas of why the ice sheet changes over time, did anyone else notice that the little fireball in the sky was "accidently" left off of the list?

Right, CO2. Had nothing to do with the closing of the Panama Strait or the rising of the Himalayan Mountains and the Tibetan Plateau. There is no proof that temperature follows CO2 only in the model world does temperature follow CO2.

There was an ice age during the Ordovician with CO2 levels 10X higher than today.

Using the same brilliant thinking as my BU buddies, this proves that high CO2 levels force extreme global cooling.

"The one question that scientists do not know the answer to is why was there a sudden drop in atmospheric CO2 three million years ago? "

Obviously, it was the famous tipping point they keep talking about.

High temps and high CO2 levels are very unstable. Once either one gets too high and too unstable, it cascades. We should all be enjoying our good luck right now, instead of being scared, paranoid little freaks.

"The one question that scientists do not know the answer to is why was there a sudden drop in atmospheric CO2 three million years ago?"

I'm pretty sure there is more than one. Like whether or not CO2 levels have a significant impact on climate.

this is bogus global warming is nothing more than propaganda. the earth is actually warming but we have nothing to do with it.

Thanks Brett for all the great information.

I saw this today in the BBC and though I know you keep abreast of all this, since it is part of an ongoing development some might be interested:

"Arctic ice 'is at tipping point'"
http://news.bbc.co.uk/2/hi/science/nature/7585645.stm

As I understand it, while current data show that melting is not as much as last year with a couple of weeks to go, various factors indicate that the trend is toward more, including an increase in rate and some thinning. In any case, we will all know where 2008 fits with other years soon, and I'm sure Brett will post about it.

Although I've lost interest in continuing to participate here on a regular basis because of ongoing bias and the sometimes rude/sarcastic quality of arguments, I am interested in the posts in which Brett shares his expertise to show us more in-depth information.

I am also concerned that the circular and shallow arguments of the denier/delay machine and its fans can be more convincing than they should be. Those who drop in here might think they will find a discussion of Global Warming, rather than an ongoing attempt by participants to create a consensus that majority science is full of baloney. Many of these arguments have been being put forward for several decades, and scientists have made huge efforts to include and understand the points made, get better at communicating how science works, and provide answers/improve models. I think once a point has been answered dozens or hundreds of times, repeating it only deceives those who accept assertions without checking sources.

Making insulting claims about the IPCC, Dr. Hansen, Al Gore, people here, and others is part of the democratic process; so is my claim that this is dishonest or that if you believe it you have been deceived. If you have not joined the club, these insults have the purpose of creating doubt and a little research into the actual history of these people will show quite a different picture. A general figure of about 98% to 99% of credible scientists agree that global warming is happening and perhaps a slightly lower figure agree that it is man-made.

In any case, whatever you think about CO2, it is clear that we have a number of critical issues around pollution, toxins in the environment, an ocean in crisis with pollution and overfishing, etc. It is less costly to address the causes of extreme weather events than to rescuing its victims. An excellent example brought to my mind recently is the removal of wetlands in favor of development around New Orleans, and the failure to fund adequate strengthening of levees, not only near New Orleans, but in many other locations (most recently the upper Mississippi).

The only thing that can explain it is CO2? And these guys are scientists? Wow no wonder people have a hard time accepting AGW. So many factors involved yet this is the best they could come up with. Could it be that the only ones funding them are proponents of the CO2 farce to begin with? Rock on Oz as this stuff is getting more and more comical by the day.

I'd like to make a request of those of you posting rude comments about how stupid scientists are, how CO2 has no effect on climate, etc. Would you mind terribly including in your message what education you have had in climatology, and how many years you've been working in the field? Because otherwise we're likely to conclude you're some ignorant yahoo. Thanks in advance!

Hmmm. Mars is 99%+ co2 and "they"{it} manages to have ice. Really if we stop making co2, do all these people think it would be possible to have another ice age, all my I just think of all the things I can do like...umm...uhhh..uhh..ride snowmobile, until I run out of gas and they no longer deliever due to road closure, well wait it wouldn't matter we all would eventually die from starvation, so well shoot...lets keep making that co2 if its keeping it warmer, yesterday my temp hit 58 today it nudged 60 with most of the day in the mid -upper 50's with rain,drizzle,wind, just beautiful for August, really though once again I can't even begin to imagine how cold it would have been without global warming, like yesterday, today my thanks and appreciation goes out to all you loggers, power plant workers, suv drivers, and all the co2 producers behind the scenes, without you it would be a cold world!

What provides the greater variation in climate on the planet today, CO2 or the oceans?

CO2 continues to plague researchers minds, making the more plausible explanations impossible for them to grasp. It doesn't take very long to find more realistic theories:

"A Short Circuit in Thermohaline Circulation: A Cause for Northern Hemisphere Glaciation?" by N. W. Driscoll, G. H. Haug.
http://www.sciencemag.org/cgi/content/abstract/282/5388/436

And an article from The Woods Hole Institution:
"How the Isthmus of Panama Put Ice in the Arctic"
http://www.whoi.edu/oceanus/viewArticle.do?id=2508

D Caldwell wrote...
....When your only tool is a hammer, everything looks like a nail...

whats your tool then?

WeatherWatcher:
Thanks for nailing down the real Issues. Everything you said is true. CO2 warms our Planet for the last 660,000 years. The planet has a concentration of CO2 at 280ppm. Then after pre-industrial times, CO2 rises to 390ppm today.
Temperatures and the rise of CO2,CH4,and N20 mirror each other. They go up and down and up again at exactly the same intervals. This was the basis of the Keeling graph. If you don't believe this then look at Venus. Venus has a large atmosphere of CO2 and is warmer than it should be for it's relative distance to the Sun. In terms of forcings, the Sun has contributed to the warming only 0.12c. The greatest feedback mechanism has been water vapor. CO2 Molecules react to IR then tumble, move faster and collide with other gases and this is called warmer. We have created the greenhouse effect. It's warming the Arctic if you haven't noticed.
Also since explaining warming to you, because you have energy that doesn't mean you should waste it. Half of the great coral reef is dying. We need regulations for over fishing, Greenpeace had to chase the Japanese out of our waters for killing whales, and you laugh at this. I don't even get the joke! If America is a great Country then prove it! Your choice.
KIPP

bill-tb, I don't understand why you think that just because something influenced the earths temps 3million yrs ago means that today, the something that's now influencing the temp can't be us!

The chemistry for CO2 causing warming by its greenhouse properties is straightforward science! We are burning tons of the stuff and forcing up the concentration.

Scientist, from even as early as 1890, and across many disciplines (IPCC) have worked out what the effect of the additional CO2 would be and this has been the observe temp rise we have seen over the period.

more and more reputable organizations are puting out statements indicating that AGW is real and very dangerous and something needs to be done. Here an impressive latest statement from the Brookings Institution
7 Years to Climate Midnight

WeatherWatcher said ...
...I've lost interest in continuing to participate here on a regular basis because of ongoing bias and the sometimes rude/sarcastic quality of arguments, I am interested in the posts in which Brett shares his expertise to show us more in-depth information...

...circular and shallow arguments of the denier/delay machine and its fans can be more convincing than they should be. Those who drop in here might think they will find a discussion of Global Warming, rather than an ongoing attempt by participants to create a consensus that majority science is full of baloney. Many of these arguments have been being put forward for several decades, and scientists have made huge efforts to include and understand the points made, get better at communicating how science works, and provide answers/improve models. I think once a point has been answered dozens or hundreds of times, repeating it only deceives those who accept assertions without checking sources.

Well said mate!

Saly: I am not a scared paranoid freak. People in denial, do so because they are in fear of reality.
People that accept reality, have a better understanding of how to act and why. Global warming is an ominous fact. We are not alarmed, not afraid or choose to be lefty's, pinko's, or weirdo's. We are Americans First. We are patriots,
workers, and Businessmen. Artists, engineers and Scientists. We enjoy respect from our peers, if we deserve it. We are people, who live in a country now divided by those who have and those that don't. I have lived in Mexico City and have seen the gross poverty along side the very wealthy. I would not wish this on anyone. Not in My country for sure. We need the middle class like never before. Who ever is really running the country now, I'm not quite sure. But values like truth, honesty, and fairness should always prevail, over the special concerns of one group over any other. One person, one vote.
KIPP

Weather watcher ... you are basically trying to make the point that because the warmers got on the stage first they cannot now be displaced whether right or wrong. Nice try but that ain't how science works. You can wrap your arguements in all the concern about toxins you wish & it doesn't give them any more weight.
Regarding this " article " it is a terrible piece of FLUFF short of everything except speculation & CO2 porn. The only intelligent morsel I found raises the issue of whether CO2 leads or follows the global temp changes & I've read arguements for both cases.
Have a good Labour / Labor day folks.
Rick.

How's this for a common sense explanation? The warm period that caused Greenland to be ice-free released CO2 from the oceans, causing high CO2 levels. When the climate cooled down and glaciers returned, the cooler oceans reabsorbed all the previously released CO2. What caused the lower temps. is open to much speculation but CO2 dropping before temperatures isn't one of them. These researcher's minds are so closed they're starved of oxygen.