From NASA Goddard/GISS: same-o, same-o
Paleoclimate Record Points Toward Potential Rapid Climate Changes
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
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My favorite line was:
These guys can’t even tell a believable lie. It hasn’t warmed a tenth of a degree in the last decade, that’s nonsense.
w.
Getting a bit shrill, aren’t they?
This isn’t science; it’s speculation.
Even a madman can speculate.
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.
The man is utterly shameless..
Excuse me while I go and puke
Wherever paleo-climate studies have looked – on a regional basis – Antarctica, Greenland, Tibet – you find 2-3 degree Celsius changes with a beat-frequency of about 1000 years – some of these rises are very steep (Greenland) – within decades – and this is quite normal throughout ice-ages and interglacials. This probably translates to a global 0.5-1 degree shift.
The current warm period is expected on this frequency and not at all unusual in rate of change or amplitude – despite the presence of higher levels of CO2 and other greenhouse gases. Hansen has consistently misinterpreted the natural signal – as confirmation of his models and calculations of ‘sensitivity’ to carbon dioxide. If, as many of us calculate from the real world evidence of radiation flux measurements, CO2 can account for no more than 20-25% of the warming, then future temperatures will be determined by the natural cycle – and many paleo-climate experts think this will turn downward (see Liu’s work on Tibet featured in an earlier thread).
What is so annoying is the way that the left-liberal-green press only ever report Hansen’s opinions thus inflating the carbon currency bubble.
“Humans have overwhelmed the natural, slow changes that occur on geologic timescales,” Hansen said.
But “natural variability” has overwhelmed the alleged AGW during the last 15 years, according to other CAGW proponents; I would suggest that the CAGW movement now splinters into warring factions.
“Hansen and others noted that while the paleoclimate evidence paints a clear picture of what Earth’s earlier climate looked like…” Utter rubbish. We have no idea what the past climate was truly like. We are merely guessing.
We know as fact that the Vikings settled in Greenland and some of their settlements are just becoming apparent as glaciers recede. Those glaciers need to recede far more before the land will become farmable with primative equipment such that was possessed by the Vikings . May be Greenland needs to become several degrees (some speculate more than 4 degrees) hotter than today before it will be akin to the conditions that the VIkings enjoyed. What were the sea levels in the Northern Hemisphere at that time? That would be a good starting point since at least it would be grounded upon some basis of fact.
‘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.’
Says a lot doesn’t he. If you give me a million quid I’ll make you 20 but I cannot promise how it will unfold.
The last interglacial was 3-4degC warmer than present.
http://alsystems.algroup.co.uk/warming/CO2_temp.gif
This interglacial is steadily cooling.
http://www.climatedata.info/resources/Proxies/Ice-Cores/07-Temperature—Vostok-and-GISP2.gif
Oceans entered another 30-years long cooling period.
http://bobtisdale.files.wordpress.com/2011/12/5-no-hem.png
Per BEST own words, global records follows AMO/North Atlantic and the “human effect might be somehow overstated”. There is nothing unusual on period 1975-2005, it is equal to that of 1910-1940. AMO/NA SST are heading down again.
http://climexp.knmi.nl/data/ihadsst2_280-360E_0-70N_n.png
Fail on every level. Can I have some grants now?
can some one over there take this man to dinner and fix his head?
Complete unsubstantianted alarmist nonsense from a greedy crank, conflicted up to his ying yang – no alarmist stories, then no justification for his outrageous salary, therefore no job.
The CAGW faithful in Durban must love this alarmist stuff: “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.” So show us the proof in the geological record – the only problem is: it doesn’t exist!
Natural climate cycles are a complete heresy to the CAGW high priests – most of recent warming is due to them. Another heresy is to make the observation that global temperatures have been static/falling slightly over the past 10-12 years, likewise so is the fact that the rate of sea level rise has remained constant over the past two centuries.
The Eemian period was generally much warmer than Hansen states – unless, of course, he is right and everyone else is wrong – for instance this paper:
http://www.google.co.uk/url?sa=t&rct=j&q=eemian%20interglacial%20mean%20temperatures&source=web&cd=5&sqi=2&ved=0CEMQFjAE&url=http%3A%2F%2Fwww.mad.zmaw.de%2Ffileadmin%2Fextern%2FPublications%2Fmodel_data.pdf&ei=BuHhTqWdM4LN4QSPs9mKBQ&usg=AFQjCNG_Zv9J8AVLV1rryJcKWnr20WeAzQ&cad=rja
I think the Chinese tree ring record of Liu Y, Cai Q F, Song H M, et al., “Amplitudes, rates, periodicities and causes of temperature variations in the past 2485 years and future trends over the central-eastern Tibetan Plateau” (Chinese Sci Bull, 2011, 56: 29862994, doi: 10.1007/s11434-011-4713-7) deserves more attention. The nearly 2500 year record is far longer that Hansen’s, and shows a FLAT trend, The current ‘unprecedented’ warming was exceeded by 4 precedents from 400 to 1000.
In the first Fourier analysis I have seen of temperature data the power spectrum reveals eight(!) periodic influences at 99+% CL, with periods from 2.0 years to 1324 years. Four of these cycles are longer that Hansen’s entire ‘record.’
Repackaged BS. Now sold as clean manure available at your local home and garden center.
@Hansen
Chill out, dude. Everyone else will during the next glaciation. Beat the rush.
Two points: 1. temps are not unusual (no h. stick), and 2. CO2 is not a cause of warming: http://www.youtube.com/watch?v=WK_WyvfcJyg
Funny. I & others say that the trace gas CO2 is OVERWHELMED by stronger climate factors, that vary, such as the sun ocean etc etc. That $swindler & top bs artist Hansen has co-opted our language. There may be a theoretical basis for the trace gas CO2 having a warming effect, but there is NO EVIDENCE that it effects climate level temps… at all. If you have evidence, give it. I be waiting.
The map is completely misleading. The surface of the earth isn’ t a rectangle and that red band at the top is infilled from the hottest stations the can find 2,500 miles away. Made up data is exaggerated by the shape of the map.
heavyweight hansen and others…
8 Dec: Oregon Live: OSU faculty, students prominent at one of the world’s leading scientific conferences
By Todd Simmons, Oregon State University
SAN FRANCISCO – Researchers from around the world gathered here this week … for the annual meeting of the American Geophysical Union, and Oregon State University faculty and graduate students were prominent in the conference’s vast program.
While the United Nations’ climate change conference was generating plenty of headlines … the more than 22,000 attendees at AGU were making news of their own on issues ranging from global warming to new policy governing key federal research.
NOAA Administrator Jane Lubchenco, a faculty member on leave from OSU, delivered a plenary lecture on the federal government’s management of extreme weather events. NOAA is tracking a record 12 such events, each with damages in excess of $1 billion, this year alone – droughts, floods, hurricanes, tornadoes, blizzards and wildfire…
Lubchenco also unveiled a new scientific integrity policy for NOAA – the first for the venerable science agency, which is perhaps a more notable development than it might seem: NOAA is America’s first science agency, with roots that reach back to the presidency of Thomas Jefferson. Among other things, the policy encourages transparency in research and frees researchers to discuss findings publicly on NOAA-funded research without prior approval.
The policy change earned immediate praise for Lubchenco and NOAA, with the Union of Concerned Scientists going so far as to pass out lapel stickers for AGU attendees reading, “You’re swell, Dr. L! Thanks for moving forward on scientific integrity.”…
But current OSU faculty were just as notable at the science summit, none more so than Associate Professor Andreas Schmittner, who over the past two weeks made headlines for a recently published study in Science magazine.
He and collaborators from Princeton, Cornell, Woods Hole and elsewhere developed new climate models that show the likelihood of global warming causing temperature increases of as much as 10 degrees Celsius are extremely unlikely. An increase in the 2.4-degree range would be more consistent with the new models, and Schmittner was quoted in news accounts as saying increases of 4.7 degrees or more would be “virtually impossible.”
Climate change heavyweight James Hansen of NASA and colleagues took issue with that at a Tuesday news conference at AGU, pointing to other models showing increases of 8.6 degrees or more…
http://blog.oregonlive.com/higher-education/2011/12/osu_faculty_students_prominent.html
Wow, I must be a lot more powerful than I think, I am now rated alongside a geological timescale, megga!
Why does my left knee still ache when its cold?
“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”
Alternatively, 0.0000001 degrees of warming would move Eartgh closer to the temperature of the Sun, where any known form of life would be impossible.
Piece of piss this alarmism business, can I have a grant?
Let us have the evidence for these claims please Dr. Hansen. No evidence-claim a lie, simple as that.
Hi Willis,
Could you yet me know what the Earth’s average global surface temperature anomaly was for the periods 2000 – 2010 and 1990 – 2000.
Just eyeballing this graph would suggest that it has warmed more than a tenth of a degree between those two time periods. I’ve probably got a different graph to you though.
http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.gif
Willis is, of course, correct. The GISS LOTI linear trend for the past 120 months is basically flat.
http://i39.tinypic.com/o8t8qg.jpg
This Hansen chap is probably preparing the base for an “Eemian Hockey stick” or some other kind of stick with a stunted blade