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CO2 levels were up to 400ppm about 800 years ago. They've since dropped, but are now up again. Not exactly thousands of years.

Are you the same guy that says that NASA is reporting that CO2 makes the world colder?

Anyhow, where is the citation about the 400 ppm level? I'm getting about 250 ppm from my cites, Wikipedia.

On the debunking sites, there seems to be a common thread that goes something like this one from:

http://www.philosophical-investigations.org/Historical_CO2_levels

to wit:

Another of the IPCC tricks, well-hidden (buried under mountains of Energy department paid trivia publicised by the likes of the Guardian and Realclimate) is the ludicrous claim that CO2 levels have been historically stable, and are now exceptionally high, leading to - you -know-what (okay, a runaway greenhouse warming effect). That is either wordsmithing, or a marked case of innacuracy.

http://www.planetforlife.com/co2history/index.html shows a huge deviation, from around 300 to around 180 ppm.

The original cite was from NOAA data, sorry for the planetforlife graph, it was just easier than making people sift through the original data. The NOAA links are in there if anyone wants to go through them.

I get a lot of this cherry picking and other interesting claims when I go through the denier sites. We get a lot of "research shows", with no citations. We even get odd insinuations, like that philosophical investigations site making insinuations about an anonymous refutation of Ernst-Georg Beck's article that claims that scientists believe that CO2 levels were constant before the industrial age.

Make up that strawman, then beat the living shit out of it, I guess.

Believe or do not believe, it makes no matter.

"Everyone there apart from a few creationist psychos knows that at some point oil supply is not going to be able to keep up with demand unless there are a few incredibly major discoveries."

Only "a few incredibly major discoveries"? Are you kidding? We need a lot of incredibly major discoveries, because the discovery rate already peaked in the 1960s. The rate of new oil field discovery has not matched the rate of consumption since then, and it only continues to get worse. A lot worse. We've therefore been burning it up much faster than we've been finding new fields for a long time. We do find new oil fields, and the big oil companies are happy when that happens, but they're tiny fields compared to the "supergiant" ones that were found historically. Essentially we're still producing from a few incredibly major fields that were found decades ago, and very few new ones have turned up. Production has been maintained by finding a great many smaller fields.

You're right that it is not the end of the world, but it is an inevitability that could really ruin your day, economically-speaking.

You're a little off.
Outdoor air carbon dioxide levels were typically around 300 ppm 60 to 100 years ago, in fact, they've rarely exceeded 280 ppm for the last 400,000 years.. Nowadays they're around 360 ppm to 400 ppm - that's 20% more than just 50 years ago - a pretty abrupt change. It's also more than 25% above the previous four interglacial CO2 peak levels.
Indoor air carbon dioxide levels are typically kept around 600 ppm (at least, that's the attempt). Above 800 to 1000 ppm there's probably inadequate ventilation, though that may be using the CO2 level as a surrogate for other indoor air pollution as much as a direct problem of too much CO2. Above around 1,000 ppm people begin to complain of headaches and drowsiness
OSHA's 8-hour limit is 5,000 ppm, which you might find in an industrial environment. At that level you're also significantly affecting the percentage of O2 in the air.

Gases are compressible. Gallon is a measure of volume. Theoretically, highly compressed hydrogen would give you liquid hydrogen. Hydrogen compressed occupies 3 times more volume than gasoline for the same energy. http://www.planetforlife.com/h2/h2swiss.html [planetforlife.com]

Even more interesting than that is the fact that hydrogen can be compressed to a higher density than liquid hydrogen. That's right, at high pressures, you can obtain hydrogen gas with higher specific mass than liquid hydrogen. AND it is not even a very exotic pressure we're talking about: this gas was suggested (in a scientific article I read last year) as the most convenient way to store hydrogen for automotive purposes.

Gases are compressible. Gallon is a measure of volume. Theoretically, highly compressed hydrogen would give you liquid hydrogen. Hydrogen compressed occupies 3 times more volume than gasoline for the same energy. http://www.planetforlife.com/h2/h2swiss.html

Well let's see. Ignore the rest of the crap on this page and take a look at the long term carbon-in-the-atmosphere graph. It clearly shows that every 100-150 thousand years, the amount of carbon in the atmosphere peaks. The last peak was about 150 thousand years ago and, guess what, we are heading for a peak now. Imagine that! The amount of CO2 in our atmosphere has been following a 150 thousand year cycle, and it happens to be rising 150 thousand years since the last peak. Were there coal plants 150,000 years ago? Nope. So, what do you think caused a CO2 spike then? Hmmmm. Surely, it's not the same thing that's causing it now. No, that wouldn't be politically profitable and governments wouldn't be able to take more control of our lives if that were the case. Must be coal plants.

Since someone downmodded this because they disagreed with the facts, I decided I should post it again.

Well let's see. Ignore the rest of the crap on this page and take a look at the long term carbon-in-the-atmosphere graph. It clearly shows that every 100-150 thousand years, the amount of carbon in the atmosphere peaks. The last peak was about 150 thousand years ago and, guess what, we are heading for a peak now. Imagine that! The amount of CO2 in our atmosphere has been following a 150 thousand year cycle, and it happens to be rising 150 thousand years since the last peak. Were there coal plants 150,000 years ago? Nope. So, what do you think caused a CO2 spike then? Hmmmm. Surely, it's not the same thing that's causing it now. No, that wouldn't be politically profitable and governments wouldn't be able to take more control of our lives if that were the case. Must be coal plants.

I answered my own question.

Still, I believe that in time, these challenges can be over come.

The following web site has a major time line of human population:

Ice Age

Circa 700AD: Plagues halve European population.

763AD-764AD: From about 400 A.D. to around 900, the climate became much colder. The winters of 763-764 and 859-860 were extraordinarily cold, with the ice so thick in the Adriatic near Venice that it could hold up heavily-loaded wagons. There was ice even on the Nile.
(From a website reviewing book on climate change by H. H. Lamb, Climate History and the Modern World.) ...

850AD: (12). Four hundred years later, the agricultural base of the Tiwanaku civilization of the central Andes collapsed as a result of a prolonged drought documented in ice and in lake sediment cores (13). In Mesoamerica, lake sediment cores show that the Classic Maya collapse of the 9th century A.D. coincided with the most severe and prolonged drought of that millennium (14). In North America, Anasazi agriculture could not sustain three decades of exceptional drought and reduced temperatures in the 13th century A.D., resulting in forced regional abandonment (15).
See Harvey Weiss and Raymond S. Bradley, 'What Drives Societal Collapse?', Science, Jan. 26, 2001.



I tried doing a search for volcanic eruptions in the 700AD - 850AD era.

The following web site has an article about a massive volcanic eruptions at the headwaters of the White River 1250 years ago (750AD)

White river volcanic eruption

Below this black soil lies a thin layer of white ash from a massive volcanic eruption that occurred near the headwaters of the White River 1,250 years ago. This event was one of the largest volcanic explosions the world has seen over the past 10,000 years. Most of central and southern Yukon was covered by the ash, and traces can be found even in the Northwest Territories. With deposits more than one metre thick near the source, the White River eruption was an ecological disaster that killed many plants and animals and probably forced people to move away from the area near the eruption for many generations, until plants and animals began to return. At Annie Lake, howhttp://www.planetforlife.com/gwarm/globclimate. htmlever, the ash is thin--only several centimetres, and it is possible the impact of the eruption was not so severe here as in other places in the Yukon. Perhaps the main result of the White River eruption was that new people moved into the Annie Lake area from regions hard hit by the ash.


This site mentions a later eruption at 800AD:

Extending the Alaska Tree-Ring Record


White spruce (Picea glauca) in this region is preserved as relict trees that are dead but not decayed due to low temperatures. Subfossil trees are preserved in permafrost, glacial sediment deposits and in the White River Ash (pictured above). This last deposition resulted from a major volcanic eruption in the Wrangell Mountains around 800AD


Volcanic eruption of 1783

The Laki eruption lasted eight months during which time about 14 cubic km of basaltic lava and some tephra were erupted. Haze from the eruption was reported from Iceland to Syria. In Iceland, the haze lead to the loss of most of the island's livestock (by eating fluorine contaminated grass), crop failure (by acid rain), and the death of one-quarter of the human residents (by famine). Ben Franklin noted the atmospheric effects of the eruption (Wood, 1992).

It is estimated that 80 Mt of sulfuric acid aerosol was released by the eruption (4 times more than El Chichon and 80 times more than Mount St. Helens).

The volcanic eruption in 1783 caused the winter average temperatu

How about we let nature take its course and we worry about changing ourselves instead of the planet?

because we are seriously f***ing with nature

Let's see... incoming solar radiation either gets re-radiated back out to space, or ends up as heat energy somewhere. Incoming solar radiation that hits a solar panel gets reflected a little, goes to heat a lot, and generates a little electricity. Which eventually ends up as... heat.

The main impact of large-scale solar is how much you affect the planet's albedo (tendency to reflect the energy back into space). If you put your solar installations over surfaces with similar albedo (say, parking lots- they are both pretty black), you're good. Much less impact than, say, melting high-albedo ice caps.

I've forgotten the details, but I believe that the potential temperature forcing due to the albedo change of large-scale solar power is much, much smaller than the forcing of, say, doubling atmospheric CO2 (which at current trends we should easily reach in less than 100 years).