H2O falls out itself.

It’s called “rain.

In an attempt to understand what is happening to the earth without trying to politicize it. I have a few questions. Just to show my bias I spent most of the last thirty years as a computer programer and DBA. I can write a program the will predict that we are going to be as warm as it was at the Permian Triassic boundary or we are going to enter a new ice age next week. Just give me the money and let me know what outcome you want. For two examples the cigaret companies never funded any research showing a link between cancer and tobacco. Peta has never funded any research showing any benefit of drug research on animals.

The problem is the weather bureau has trouble predicting what the weather is going to be next week with degree of accuracy. Back in the dark ages when I was taking aviation weather(1968). My instructor said if you want to predict weather more that 48 hours in advance just say it is going to be the same as to day and you will be just as accurate.

It is my understanding that there have some 20 periods of Glaciation and interglacials during the Pleistocene/Holocene. See new time frame for Pleistocene.
http://johnhawks.net/weblog/topics/geology/timescale/pleistocene-quaternary-redefinition-2009.html
We are now in an interglacial. A period of global climate change with increasing temperatures.
http://en.wikipedia.org/wiki/File:Atmospheric_CO2_with_glaciers_cycles.gif

The climate had been growing warner for the last ten thousand years with periods of cooling interspersed (little ice age) the followed The Medieval Warm Period. The warmest period was some 8000 years ago. The cooling period before the little ice age seems to coincide with the fall of the Roman Empire. The warmest period during the interglacial was from 8000 to 2500 years ago.
http://en.wikipedia.org/wiki/Interglacial#Interglacial_optimum
http://en.wikipedia.org/wiki/File:2000_Year_Temperature_Comparison.png
http://www.climatechange.umaine.edu/Research/Contrib/html/02.html
http://en.wikipedia.org/wiki/File:Holocene_Temperature_Variations.png

The Eemian 130,000 years ago was warmer than it is today.
http://en.wikipedia.org/wiki/Eemian_Stage
Cenozoic climate
Paleocene, Eocene, Oligocene, Miocene, Pliocene
Cooler Warmer, Cooler Cooler Cooler

My question is why is everyone upset about changes that do not appear at all unusual? Yes the climate may be growing warmer but it is very unlikely to be as warm as it was in the Miocene much less the Eocene. The big danger mankind faces is what happens at the end of the interglacial.

What makes this (global warming) so much different that all the others?

How do we resolve the evidence of global warming on Mars?

It is my understanding that CO2 tracks changes in global temperature very closely but seems to lag by about 800 years.

The most common green house gas is not CO2 it is H2O what are we proposing to do about this problem of water vapor?

This by the way does not mean that I think that we should not take care of the planet. I just think that we are jumping a very small fluctuations and crying the sky is falling.

Thank you, SLC, for answering. The answer is much as I expected: no. I think any honest appraisal of the available science would lead most to the same conclusion. A couple of follow up questions, if I might, for your attention.

First, as you have indicated that the science behind AGW is not as established as, say, evolution, is it fair then to classify everyone and anyone who might question the validity of the AGW theory as a nut case, on par with creationists and those who deny the link between HIV and AIDS? Or, rather, perhaps I should ask the question in a different way. Is there no room for rational dissent from the prevailing AGW wisdom? Is there no room for skepticism? Or, are all skeptics, who may question the linkage between rising temperatures and human activities, simply either irrational or disingenuous?

Second, I am wondering what might cause you, or any AGW proponent, to question the validity of the AGW theory. In other words, were I to set out to prove or disprove the linkage between rising temperatures and human activities (namely, the release of “greenhouse gasses” into the atmosphere), what findings might cause me to conclude that there *is* no linkage. For instance, over a period of time, if I observe, perhaps, that temperatures are falling, ice cover is increasing over the poles and/or that sea levels either remain static or drop. These are just some ideas, and I would be curious to hear exactly what would cause you to conclude that the theory of AGW, as we both, I believe, understand it, is invalid.

Thank you!

George Will apparently did not know that he was talking about irrelevant winter sea ice cover measurements. While he is one smart fella, he should stick to stuff he knows, like baseball.

What is relevant is the summer minimum year round ice cover, average ice thickness in the year round cover, and the volumetric winter season recovery. For these, there appear to have been a substantial change. The trends are for permanent summer ice to be less in area, for the permanent ice to be thinner, and for single year recovery ice to be more in area but relatively thin. The latter is important in that there is more rapid melt in the summer (peak loss being in early September). And all of this leads to more heating of the Arctic waters in summer.

Well there is a rather large asteroid coming for us in 2029, but fortunately it’ll just miss us this time; when it comes back around in 2036, though, we might not be so lucky. The “orbital cannon” mr burns suggests is as firmly rooted in pop culture as the giant lizard he mentions (as do you; funny how you both use the same images…almost like you both read it somewhere…or perhaps you’re just plagarizing his inane posting?), and both are equally idiotic in terms of scientific accuracy. An orbital cannon would be both inefficient and ineffective (instead of getting hit with one million-ton asteroid, we get hit with a milion tons of large chunks of asteroid! Yay!); far better (and more elegant) is the suggestion that we put a small satelite close to the asteroid (and have it adjust it’s orbit whenever it gets to close) then let the gravitational attraction between the two correct the problem over the next few years.

Despite your ignorant snark, near-Earth objects, especially asteroids, are a very real and potentially imminent threat. Of course, the obvious solution is to fund increased observation of objects that cross our orbit, not some moronic “space gun.” But then, to someone who thinks global warming is some kind of conspiracy, I suppose the planetary equivalent of a tin-foil hat probably looks pretty good.

Greenland will likely be a bit more hospitable to live in with global warming. How much consolation that offers to the drying southwest and plains, coastal cities underwater, salt intrusion to coastal farming, etc, etc, is the question. How many hundreds of millions will move to Greenland and other northern climes that are much too sandy to grow much food in?

While the human species is very adaptable, human civilizations and societies are much less so. Many have collapsed as a result of climate change, whether caused by natural causes or human (deforestation can cause local climatic changes).