Posted on 12/09/2011 11:25:38 AM PST by Ernest_at_the_Beach
From NASA Goddard/GISS: same-o, same-o
Paleoclimate Record Points Toward Potential Rapid Climate Changes
The average global surface temperature of Earth has risen by .8 degrees Celsius since 1880, and is now increasing at a rate of about .1 degree Celsius per decade. This image shows how 2010 temperatures compare to average temperatures from a baseline period of 1951-1980, as analyzed by scientists at NASA’s Goddard Institute for Space Studies. Credit: NASA GISS
New research into the Earth’s paleoclimate history by NASA’s Goddard Institute for Space Studies director James E. Hansen suggests the potential for rapid climate changes this century, including multiple meters of sea level rise, if global warming is not abated.
By looking at how the Earth’s climate responded to past natural changes, Hansen sought insight into a fundamental question raised by ongoing human-caused climate change: “What is the dangerous level of global warming?” Some international leaders have suggested a goal of limiting warming to 2 degrees Celsius from pre-industrial times in order to avert catastrophic change. But Hansen said at a press briefing at a meeting of the American Geophysical Union in San Francisco on Tues, Dec. 6, that warming of 2 degrees Celsius would lead to drastic changes, such as significant ice sheet loss in Greenland and Antarctica.
Based on Hansen’s temperature analysis work at the Goddard Institute for Space Studies, the Earth’s average global surface temperature has already risen .8 degrees Celsius since 1880, and is now warming at a rate of more than .1 degree Celsius every decade. This warming is largely driven by increased greenhouse gases in the atmosphere, particularly carbon dioxide, emitted by the burning of fossil fuels at power plants, in cars and in industry. At the current rate of fossil fuel burning, the concentration of carbon dioxide in the atmosphere will have doubled from pre-industrial times by the middle of this century. A doubling of carbon dioxide would cause an eventual warming of several degrees, Hansen said.
In recent research, Hansen and co-author Makiko Sato, also of Goddard Institute for Space Studies, compared the climate of today, the Holocene, with previous similar “interglacial” epochs – periods when polar ice caps existed but the world was not dominated by glaciers. In studying cores drilled from both ice sheets and deep ocean sediments, Hansen found that global mean temperatures during the Eemian period, which began about 130,000 years ago and lasted about 15,000 years, were less than 1 degree Celsius warmer than today. If temperatures were to rise 2 degrees Celsius over pre-industrial times, global mean temperature would far exceed that of the Eemian, when sea level was four to six meters higher than today, Hansen said.
“The paleoclimate record reveals a more sensitive climate than thought, even as of a few years ago. Limiting human-caused warming to 2 degrees is not sufficient,” Hansen said. “It would be a prescription for disaster.”
Hansen focused much of his new work on how the polar regions and in particular the ice sheets of Antarctica and Greenland will react to a warming world.
Two degrees Celsius of warming would make Earth much warmer than during the Eemian, and would move Earth closer to Pliocene-like conditions, when sea level was in the range of 25 meters higher than today, Hansen said. In using Earth’s climate history to learn more about the level of sensitivity that governs our planet’s response to warming today, Hansen said the paleoclimate record suggests that every degree Celsius of global temperature rise will ultimately equate to 20 meters of sea level rise. However, that sea level increase due to ice sheet loss would be expected to occur over centuries, and large uncertainties remain in predicting how that ice loss would unfold.
Hansen notes that ice sheet disintegration will not be a linear process. This non-linear deterioration has already been seen in vulnerable places such as Pine Island Glacier in West Antarctica, where the rate of ice mass loss has continued accelerating over the past decade. Data from NASA’s Gravity Recovery and Climate Experiment (GRACE) satellite is already consistent with a rate of ice sheet mass loss in Greenland and West Antarctica that doubles every ten years. The GRACE record is too short to confirm this with great certainty; however, the trend in the past few years does not rule it out, Hansen said. This continued rate of ice loss could cause multiple meters of sea level rise by 2100, Hansen said.
Ice and ocean sediment cores from the polar regions indicate that temperatures at the poles during previous epochs – when sea level was tens of meters higher – is not too far removed from the temperatures Earth could reach this century on a “business as usual” trajectory.
“We don’t have a substantial cushion between today’s climate and dangerous warming,” Hansen said. “Earth is poised to experience strong amplifying feedbacks in response to moderate additional global warming.”
Detailed considerations of a new warming target and how to get there are beyond the scope of this research, Hansen said. But this research is consistent with Hansen’s earlier findings that carbon dioxide in the atmosphere would need to be rolled back from about 390 parts per million in the atmosphere today to 350 parts per million in order to stabilize the climate in the long term. While leaders continue to discuss a framework for reducing emissions, global carbon dioxide emissions have remained stable or increased in recent years.
Hansen and others noted that while the paleoclimate evidence paints a clear picture of what Earth’s earlier climate looked like, but that using it to predict precisely how the climate might change on much smaller timescales in response to human-induced rather than natural climate change remains difficult. But, Hansen noted, the Earth system is already showing signs of responding, even in the cases of “slow feedbacks” such as ice sheet changes.
The human-caused release of increased carbon dioxide into the atmosphere also presents climate scientists with something they’ve never seen in the 65 million year record of carbon dioxide levels – a drastic rate of increase that makes it difficult to predict how rapidly the Earth will respond. In periods when carbon dioxide has increased due to natural causes, the rate of increase averaged about .0001 parts per million per year – in other words, one hundred parts per million every million years. Fossil fuel burning is now causing carbon dioxide concentrations to increase at two parts per million per year.
“Humans have overwhelmed the natural, slow changes that occur on geologic timescales,” Hansen said.
Patrick Lynch
NASA’s Earth Science News Team
More propaganda from the Globes leading data manipulator.
Hansen is another “scientist” in the mold of Paul Ehrlich. A declinist who sees humanity as the problem, and big government socialism as the solution.
That old scam. We need to fired Hansen.
I had no idea Hansen was still at it ...
http://www.youtube.com/watch?v=NHozn0YXAeE
MMMBop
wow, who knew we would become like gods so soon? able to control the earth !!
now, if i could just get my toilet to flush with a single pull, then life would be complete.
Uh huh. Can Mr. Hansen tell us if it will rain tomorrow?
"Hey Hanson, the house isn't on fire."
"Uh, well, it's POISED to catch on fire, what with all that wood and those drapes and, and... just look at that newspaper. So... live in the backyard and tear down the house, because you never be too careful."
What that means is the last Glacial Period was probably so much colder than those that preceded it that the oceans cooled down enough to retard the sort of increase in evaporation we would normally have had.
That would, in turn, delay a return to the normal Glacial Period.
Our planet has been in the grip of an Ice Age for the last 2.5 million years. The 20 or so cycles reflected in the Antarctic Ice Sheet reveals that the trend has been colder and colder.
In short, we are in a sort of "drought". Interesting that Hansen did say we were about 1 degree C short of the temperature achieved in the last interglacial (the 10,000 year long warm period between each 100,000 year long period of glaciation).
Today's massive ice storm beating down on Greenland (check your Intellicast.com global infrared map) may well TIP us over to more ice formation, with less warming ~ and a return to a normal condition.
So what? Interesting how this “problem” screams for a totalitarian solution, to be administered by a strong centralized central planning-style government that can control *everything* down to the lightbulbs in my living room.
And for extra fun, the population needs to be highly immobilized, only to be transported enmass, on methods requiring contact with state security.
But this is the totalitarian future Hansen dreams of. For now, ill be happy to see NASA utterly disbanded and defunded. If they have a dime to pay this A-hole, they apparently have too much money already.
Kohler has a pot for you.
"Humans have overwhelmed the natural, slow changes that occur on geologic timescales"
However, Humans Evolved on Earth and Earth is an ever changing dynamic system...
So for Millions of years the planet only evolved animals that have minimal impact on the biosphere, but then it decided to increase brain size rather than claw and teeth size.
So if we are a product of Earth, then the Eath itself is causing these changes....
Stop Hitting Yourself!!!
So Libs can use relativistic morality to justify just about any sort of human behavior except mining and manufacturing?
So unless it is space aliens spewing CO2, the Earth is just hurting itself Mr. Hansen.
116 Responses to Hansen: “Humans have overwhelmed the natural, slow changes that occur on geologic timescales”
Never mind all this, what about NASA’s Muslim outreach? That’s far more important.
[ Hansen is another “scientist” in the mold of Paul Ehrlich. A declinist who sees humanity as the problem, and big government socialism as the solution. ]
If Humanity is the problem then why DID THE EARTH EVOLVE THEM?
I Wanna see either of those bozoes answer that one.
*************************EXCERPT***********************************
John Shade says:
There is the possibility here of a new bootstrap event. According to this post Real Science (http://www.real-science.com/understanding-man-global-warming) ‘In the year 2000, Hansen and his buddies decided to give underachieving global warming a boost – by adding 0.6 degrees on to the disappointing US data set.’ So perhaps the above claim of a rise of 0.8C thanks to his work at the Goddard Institute for Space Studies is a bit of an exaggeration. In either case, the bootstrap event whereby an observer gets extremely distressed by the data he has just created is worthy of further study.
And thinly veiled in the message, man is the problem, so fewer men is the solution.
Centralized government is the most efficient means to fewer men. Hundreds of millions of fewer men. Billions of fewer men.
***Humans have overwhelmed the natural, slow changes that occur on geologic timescales,” Hansen said.***
God asked: “Who is this Hansen, and how did I miss giving him a brain?”
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