But Hansen said that we could stabilize the climate at 350 ppm. I’m devastated.
There is no agreed beginning year to the Little Ice Age, although there is a frequently referenced series of events preceding the known climatic minima. Starting in the 13th century, pack ice began advancing southwards in the North Atlantic, as did glaciers in Greenland. The three years of torrential rains beginning in 1315 ushered in an era of unpredictable weather in Northern Europe which did not lift until the 19th century. There is anecdotal evidence of expanding glaciers almost worldwide. In contrast, a climate reconstruction based on glacial length[7][8] shows no great variation from 1600 to 1850, though it shows strong retreat thereafter.
For this reason, any of several dates ranging over 400 years may indicate the beginning of the Little Ice Age:
1250 for when Atlantic pack ice began to grow
1300 for when warm summers stopped being dependable in Northern Europe
1315 for the rains and Great Famine of 1315-1317
1550 for theorized beginning of worldwide glacial expansion
1650 for the first climatic minimum.
http://en.wikipedia.org/wiki/Little_Ice_Age
Ah, the good old days of climate stability, when everything was just right.
I have found this to be a rather useful summary – which provides the context for this paper – and it is from Nature (in an earlier era). I’m not sure how the team might have ‘adjusted’ the ice core data since then, but since the ice cores themselves must still be the same, maybe they haven’t.
“The Greenland (Arctic) and Vostok (Antarctic) ice cores are particularly informative, offering fine temporal resolution and continuity. This has revealed surprising oscillations of climate on a millennial scale within the main 100-kyr cycle. The Greenland Ice Core Project (GRIP) identifies some 24 interstadials through the last ice age with average temperature rising rapidly by ~7 C over just decades. Further ice and sediment cores from around the world are demonstrating the global scale of these major climatic events.”
From: Hewitt, G. 2000. The genetic legacy of the Quarternary ice ages. NATURE, Vol. 405, 22 June 2000 (www.nature.com)
Again: “with average temperature rising rapidly by ~7 C over just decades.”
They fell fast also!
In reference to LIA, I have placed it around 1250 due to the Vikings in Greenland being driven out around then. With climate shifts being a regional phenomena and one hemisphere leading the other it is difficult to say. Some say there is a 1200 year cycle that drove Minoan, Roman and Medieval Warm periods and the following cold periods. The timing could be as short as 800 years but the cooling towards the LIA may have started as early as 1000 just when the Vikings started to settle Greenland. There were multi hundred year old forests in locations that were glaciated during the LIA and the forests died out from the extreme cold. Those forests have not yet begun to regenerate!
I would venture a guess the current cooling started about 1940 and we have been sliding towards the next period of mini glaciation. Each warm period does not achieve the warmth of the last one and seems to be a bit shorter. That goes back to the Holocene Optimum and there are one K year cycles evident throughout the last 10,000 years!
I do not trust much anything from WIKI to be valid regarding climate history! The Chicken Little Brigade is still evident there!
Did anyone see “Cantore Stories” on the Weather Channel about Barrow, AK? It was unmitigated warmist propaganda (the ice is melting! the polar bears are doomed!)