Quote:
Overall, the panel agreed that the warming in the last few decades of the 20th century was unprecedented over the last 1,000 years, though relatively warm conditions persisted around the year 1000, followed by a "Little Ice Age" from about 1500 to 1850.
The scientists said they had less confidence in the evidence of temperatures before 1600. But they considered it reliable enough to conclude there were sharp spikes in carbon dioxide and methane, the two major "greenhouse" gases blamed for trapping heat in the atmosphere, beginning in the 20th century, after remaining fairly level for 12,000 years.
Between 1 A.D. and 1850, volcanic eruptions and solar fluctuations were the main causes of changes in greenhouse gas levels. But those temperature changes "were much less pronounced than the warming due to greenhouse gas" levels by pollution since the mid-19th century, it said.
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And this gets us to the real debate... The problem isn't that it got warmer... (The earth has been cycling hot/cold for a long time -- Greenland used to have farms, not just ice)
It's whether or not the RATE of change recently has been altered too much by human activity. But some like to deny the existence of the natural cycles... and some like to deny the existence of the recent rapid warming.
So we just end up with shouting instead of rational science.
