[QUOTE="N30F3N1X"][QUOTE="comp_atkins"]the earth's warming / cooling cycles, including effects of the sun, take centuries if not millennia to play out, with significant change taking vastly long times on a human timescale. the fact researchers are seeing RATES of temperature change never before seen over a half a million year time period points to some other factor at play other than natural cycles.
comp_atkins
link plz
read a few months ago.. will have to see if i can dig it up. a few sources. gist of what i said from articles..  though i was off on the time scale.
http://www.slate.com/blogs/bad_astronomy/2013/03/13/global_warming_new_study_shows_warming_is_faster_than_it_has_been_in_11.html
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better source.
http://www.nsf.gov/news/news_summ.jsp?cntn_id=127133&org=NSF&from=news
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quoted from 2nd link:
This research shows that we've experienced almost the same range of temperature change since the beginning of the industrial revolution," says Major, "as over the previous 11,000 years of Earth history--but this change happened a lot more quickly."
"The Earth's climate is complex and responds to multiple forcings, including carbon dioxide and solar insolation," Marcott says.
"Both changed very slowly over the past 11,000 years. But in the last 100 years, the increase in carbon dioxide through increased emissions from human activities has been significant.
"It's the only variable that can best explain the rapid increase in global temperatures.
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Marcott says that one of the natural factors affecting global temperatures during the last 11,300 years is a gradual change in the distribution of solar insolation linked with Earth's position relative to the sun.
"During the warmest period of the Holocene, the Earth was positioned such that Northern Hemisphere summers warmed more," Marcott says.
"As the Earth's orientation changed, Northern Hemisphere summers became cooler, and we should now be near the bottom of this long-term cooling trend--but obviously, we're not."
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^^ this is significant.  the orbital variations of the planet should make the northern hemisphere cooler.. as it had been trending for thousands of years, but then an abrupt stop.
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strikingly:
What that history shows, the researchers say, is that during the last 5,000 years, the Earth on average cooled about 1.3 degrees Fahrenheit--until the last 100 years, when it warmed about 1.3 degrees F.
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 so globally we've been in a cooling trend over the past 5000 years where the planet cooled on avg. ~1.3F  then in the last century aloneit suddnly and sharply reversed trends to warm in 1 century that amount which it took 50 previously to cool.
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full study if interested
http://www.sciencemag.org/content/339/6124/1198.full
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