I was just looking at the Key Indicators page from NASA, which shows global temperatures over the past 130 years. The smoothed line is based on a 5-year mean, which is arbitrary so this analysis should be taken only as a first-order calculation.
But it's clear that from 1880 to around 1915, nothing much happened. Then for the next 25 years, temperatures rose rapidly, roughly .4C. After which 40 years of very little change (actually a small decline) and then 25 years of rapid increase. Looks like just about .5C during the period. Due to the 5-year mean, data since 2005 is incomplete and not shown, but eyeballing, it seems to have leveled off.
Nobody of any credibility denies that we have warmed somewhat in the past 150 years, although some reasonable people think the rise is exaggerated by changes in land use. However, even taking NASA's numbers (not suggesting that they originated them), the pattern since 1880 makes the CO2 theory a little dicey. We had decadal periods with, respectively no rise, a sharp rise, no rise, and a sharp rise. The sharp rises took place in periods when CO2 was not a significant driver and when it was. The placid periods included a pre-AGCO2 period and one during which CO2 was rising rapidly. The CO2 "signal" isn't evident.
You can always fix this with a computer model by declaring a CO2 signal, subtracting it from the recorded numbers, and identifying whatever remains as natural variation. However, the argument that the increase can only be manmade CO2 emissions because the pattern is unprecedented doesn't stand up.
Subscribe to:
Post Comments (Atom)
2 comments:
Most normal people with a functioning brain have pretty much figured out by now that man-made global warming is a gigantic hoax. It has been foisted on us by many of our genius politicians, so-called "scientists", the gullible media, et al.
Actually, "scam" would be a better choice of words, since lots of people and politicians are trying to make and have made gazillions off this fraud, including one of our illustrious former vice-presidents, that ultimate capitalist, Al Gore., all at the expense of the hapless taxpayer and consumer. As usual.
This house of cards is collapsing, and rapidly.
The only thing that is being polluted is the minds of our children, who are being indoctrinated and propagandized in the public school system.
I don't allow anonymous comments, but a comment from someone named "John" whose profile is not accessible, comes close.
John should open his profile to public view if he wants to engage in public discussions.
Post a Comment