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20th Century Warmest In 1200 Years
gcranston writes "Research from the University of East Anglia in Norwich, U.K. shows that the 20th century was the warmest for the northern hemisphere since approximately 800AD. Historical climate data were calculated from weather 'proxies' such as tree rings, ice cores, and seashells from Europe, Asia, and North America, and attempted to address the shortcomings of earlier studies. The findings support the argument for global warming as a result of human interference rather than natural climate change."
You're wrong. Please read the article before trying to sound all educated and scientific, because you're neither.
There must be something we can do about the shitty moderation taking place around here. Over the last few weeks I've seen more instances of downright BAD moderation than in the past several years.
This post is actually quite good. The writer could have gone into more depth but he certainly is correct in his assesment that we are currently in an inter-glacial phase. However if we are going to go back into a glacial period then a better guesstimate might be that it is more than 5,000 years away.
The simple fact is that we have gone through at least 20 ice cycles in the last 2 million years and that the earth has been cold for about the last 20-30 million years. Prior to this recent cooling - earth was warm continuously throughout the Triassic, Jurasic and Cretaceous which is a period of over 200 million years. By warmer I mean an average global temperature of about 20 degrees warmer.
It should be noted that the poles were not ice covered until the present cooling which seemed to get going during the miocene.
At some point the planet in all likelihood will warm up. The reason is that for over 85% of the history of the planet since the end of the Precambrian - the planet was warm (say about 570 million years). There have only been a couple of times in the geological past when it has been as cool as now - so it does make sense that at some time the planet will probably revert back to normal.
Furthermore, if one compares the Ordovician ice age to the present, one finds that CO2 levels were about 13x to 17x higher than now and still the planet cooled into an ice age - then warmed back up. So it would appear that CO2 levels back then were not the deciding factor. If CO2 was not the deciding factor back then - then one would be wise to question if it has any significance today. In fact the Ordovician cooling is correlated with the Taconic orogeny just as the present cooling is correlated with the mountain building which has occured since the end of the Cretaceous. This includes the Rockies, Pyrannenes, Andies, Himalain, two hellenic mountain ranges, the tibetian and colorado plateaus... Ie - a large amount of land pushed to high elevation. It is perfectly obvious that mountain tops reflect energy back into space just as it is perfectly obvious that moist air at sea level tends to hold solar energy.
This is ESPECIALLY so when one checks the absolute humidity (H2O) which we KNOW is responsible for the earth being about 30 degrees warmer than it would be were the water vapour not in the atmosphere. Compared the the 50,000 to 80,000 PPM of H2O in the atmosphere at sea level in the tropics, the change of 70 PPM in CO2 over the last few hundred years is totally negligable. One cannot even add the CO2 measurements to the water vapour measurements because the uncertanty of the water vapour measurments masks the total CO2 by several times.
What is truely amasing is that H2O is not even counted as a green house gas by many of the folks who are most conserned about global warming. Yet we literally would be freezing our butts off were it not for H2O in the atmosphere.
The oceans have a moderating effect on a thousand year time scale. Since it was warmer during the medieval warm period by this guestimate it makes sense that earth would warm up now.
People who really want to know what is going on mind you should study paleoclimatology. The geological record of climate does shed light on how the earth functions.
Another thing that is truely amasing is how little perspective most climate change people have of the scale of geological time. If we were to map say the Encyclopeadia Britannic to the time since the beginning of the Cambrian - then each book in the set would represent something like 30 million years and each page would represent about 3,000 years. On this scale the climate warming people are looking at day usually contained on the last page and normally within the last couple paragraphs of the lsat page of the last book. Meanwhile they ignore