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Global Temperatures Are Close To 11,000-Year Peak
ananyo writes "Global average temperatures are now higher than they have been for about 75% of the past 11,300 years, a study published in Science suggests. Researchers have reconstructed global climate trends all the way back to when the Northern Hemisphere was emerging from the most recent ice age. They looked at 73 overlapping temperature records including sediment cores drilled from lake bottoms and sea floors around the world, and ice cores collected in Antarctica and Greenland. For some records, the researchers inferred past temperatures from the ratio of magnesium and calcium ions in the shells of microscopic creatures that had died and dropped to the ocean floor; for others, they measured the lengths of long-chain organic molecules called alkenones that were trapped in the sediments. From the first decade of the twentieth century to now, global average temperatures rose from near their coldest point since the ice age to nearly their warmest, they report (abstract)."
I think you and I have been given two different definitions of "Ice Age" http://en.wikipedia.org/wiki/Quaternary_glaciation
Title: Global Temperatures Are Close To 11,000-Year Peak
Actual first line: Global average temperatures are now higher than they have been for about 75% of the past 11,300 years
Some peak - it's barely in the first quartile.
Well, that is wonderful news since about that long ago was the 'end' of the last ice age when temperatures were so low we were having massive die offs due to the cold climate.
Warming is good for life. You might not be acclimated to it but the reality is when we have periods of cooling we have die offs and when we have periods of warming there is an expansion of species, of biodiversity. The Earth has been much warmer in the past and that was good for life.
I welcome warmer temperatures. It has been too cold in the last thousands of years.
All this fussing about warming is ignoring the real problem. Global Warming is just a distraction from the real issue of toxic pollution.
The US is highest per capita, yes, but China holds the majority in total emissions. And those are 2011 numbers, they've had a whole year to up the ante(note from 2010-2011, the US went down a little bit, China went up 17%). Think where the world will be when China surpasses us per capita.
captcha: equality
Here's why you should care:
http://www.skepticalscience.com/global-warming-positives-negatives-intermediate.htm
"When information is power, privacy is freedom" - Jah-Wren Ryel
1) Why would an 11,300 year data set imply cherry picking? Because it is not a round enough number for you? Perhaps this temperature record is based on foraminifera. Perhaps those are obtained through gravity or piston coring. Perhaps in regions where you need a high enough sedimentation rate to resolve temperatures at 200-400 year intervals, you can only recover 11,300 years. I have only briefly read the article, but it is likely that before 11,300 years, they did not have the time resolution to accurately resolve the temperature prior to this point. This is a data resolution issue, not an "i'm hiding the truths from you" issue.
2) It is the rate of those changes that the authors are highlighting. Absolute temperatures aren't that telling (it has been both much colder and much warmer on earth at various times in history). If the current rate of temperature change had previously occurred in the past 11,300 years (i.e. was driven by natural sources) then they would have seen some indication of it. It would not have been as pronounced as the current trend, due to lower temporal resolution (which acts as a low pass filter), but it still would have appeared.
I don't think anyone is arguing that there are not climate cycles (see Milankovish, also, straw man). But you are comparing events that are happening on much different time scales. Prior to 100 years ago, the temperature had been falling for ~5000 years. In the past 100 years, the temperature has risen to what it was 5000 years ago. Clearly whatever cycle was occurring on a 10000 year period is not the same cycle that we are dealing with now.
Opinions were like kittens, I was giving them away.