Ocean temperatures and sea level increases 50 percent higher than previously estimated

Jun 18, 2008

New research suggests that ocean temperature and associated sea level increases between 1961 and 2003 were 50 percent larger than estimated in the 2007 Intergovernmental Panel on Climate Change report.

The results are reported in the June 19 edition of the journal Nature. An international team of researchers, including Lawrence Livermore National Laboratory climate scientist Peter Gleckler, compared climate models with improved observations that show sea levels rose by 1.5 millimeters per year in the period from 1961-2003. That equates to an approximately 2½-inch increase in ocean levels in a 42-year span.

The ocean warming and thermal expansion rates are more than 50 percent larger than previous estimates for the upper 300 meters of oceans.

The research corrected for small but systematic biases recently discovered in the global ocean observing system, and uses statistical techniques that “infill” information in data-sparse regions. The results increase scientists’ confidence in ocean observations and further demonstrate that climate models simulate ocean temperature variability more realistically than previously thought.

“This is important for the climate modeling community because it demonstrates that the climate models used for assessing sea-level rise and ocean warming tie in closely with the observed results,” Gleckler said.

Climate model data were analyzed from 13 different modeling groups. All model data were obtained from the WCRP CMIP3 multi-model dataset archived at the LLNL’s Program for Climate Model Diagnosis and Intercomparison (PCMDI).

Ocean temperatures and sea level increases 50 percent higher than previously estimated
Estimates of ocean heat content and sea surface temperature. Upper: Comparison of our upper-ocean heat content with previous estimates (red1 and blue12) for the upper 700 m. The straight lines are linear fits to the estimates. The global mean stratospheric optical depth(arbitrary scale) at the bottom indicates the timing of major volcanic eruptions. The brown curve is a three-year running average of these values, included for comparison with the smoothed observations. Lower: Comparison of thick black line, as in a with the thick red line; thin red lines indicate estimates of one standard deviation error) results with sea surface temperature (blue; right-hand scale). All time series were smoothed with a three-year running average and are relative to 1961.


Although observations and models confirm that recent warming is greatest in the upper ocean, there are widespread observations of warming deeper than 700 meters.

Results were compared with recent estimates of other contributions to sea-level rise including glaciers, ice caps, Greenland and Antarctic ice sheets, and thermal expansion changes in the deep ocean. When these independent lines of evidence are examined collectively, the story is more consistent than found in earlier studies.

The oceans store more than 90 percent of the heat in the Earth’s climate system and act as a temporary buffer against the effects of climate change. The ocean warming and thermal expansion rates are 50 percent larger than previous estimates for the upper 700 meters of oceans, and greater than that for the upper 300 meters.

“This is just the tip of the iceberg, so to speak,” Gleckler said. “Our ability to quantify structural uncertainties in observationally based estimates is critically important. This study represents important progress.”

The team involved researchers from the Centre for Australian Weather and Climate Research (CSIRO), the Antarctic Climate and Ecosystems Cooperative Research Centre and LLNL.

Source: Lawrence Livermore National Laboratory

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User comments : 11

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D666
2.9 / 5 (13) Jun 18, 2008
sigh. Let me be the first to toe the denialist line with the standard BS.

1) Obviously the models are wrong, since they got it wrong by 50%. Therefore predictions of GW are worthless. Since the predictions are worthless, there isn't any GW. Therefore this report is wrong.

2) There isn't any GW, since the polar bear population has doubled since we almost killed them off.

3) This is all a conspiracy by the liberal fascist dictatorial libertarian communist treehugging homosexual baby-eating tree-huggers, probably the same people who faked the moon landing.

4) It's TYRANNY, I tell you TYRANNY!!!

Let the games begin.
Sean_W
2.8 / 5 (13) Jun 18, 2008
Breaking news: Sydney Opera House retroactively flooded. Tragic 6 cm increase in sea levels kills millions. Definitely caused by SUVs, video games, obese Americans and statistical manipulations. Experts warn that all hope lost if research funding not tripled.
Mercury_01
2.9 / 5 (7) Jun 18, 2008
Why dont we just drown ourselves in advance?

NotParker
3.2 / 5 (9) Jun 18, 2008
Sea level has gone down the last 2 years.

http://sealevel.c...obal.jpg

Ignore the black line mean to hide the fact the blue line is going down.
tesfalcon
2.2 / 5 (5) Jun 19, 2008
I object to your inclusion of libertarians into your list. Libertarians are more likely to be conspiracy theorists than conspirators. Lots of ex-John Birchers in their ranks. Libertarians are closer akin to anarchists than communists. As for GW, you say that like its a "bad" thing.
Ninderthana
2.7 / 5 (7) Jun 19, 2008
D666,

Let me put you straight. No one denies that the world (until recently) has been warming. If the world is warming then, of course, the upper oceans will temporarily store that heat.

What is not scientifically proven is whether or not the warming has been the (primary) result of the green-house effect caused by anthropogenic CO2.

In fact, the recent leveling off or cooling of the top 700 m of the world's oceans is NOT predicted by GW models.
D666
3.9 / 5 (8) Jun 19, 2008
D666,

Let me put you straight. No one denies that the world (until recently) has been warming. If the world is warming then, of course, the upper oceans will temporarily store that heat.

What is not scientifically proven is whether or not the warming has been the (primary) result of the green-house effect caused by anthropogenic CO2.


It has also not been *proven* that cigarettes cause cancer, that evolution actually happens, that Relativity is a reality, or any other number of silly comparisons I could come up with. The denialist stance is basically binary: either something is completely 100% proven, or it is a flip of a coin. The denialists feel that all they have to do is get the slightest bit of doubt in there, and suddenly it's anyone's game.

The reality is, GW isn't 100% proven, but it is (perhaps) 95% likely. I'm just tossing that number out as an example, so don't get bent out of shape about the specifics. The point is that it *isn't* 50%, and it *isn't* anywhere near 50%. Like the creationist, you think that if you keep chipping away at the edges of things, you can "win by default".

But all the decisive arguments from denialists (as opposed to the name calling, which is no doubt fun but really irrelevant) always turn out to be BS.

Now, when I'm sitting on the sidelines watching two groups argue about something, I listen as much to what is *not* said, and *how* things are said, as I do to the arguments themselves. If one side relies mostly on personal attacks, they're probably wrong. If one side relies on arguments that are out and out manufactured, they're probably wrong. If one side plays fast and loose with stats in a way that couldn't possibly have been done accidentally, they're probably wrong. Or at least, it's reasonable to conclude that their stance is *not* based on the facts, but on some other hidden motivation. This describes the denialist stance perfectly, to a T. It also describes the creationist stance, the tobacco company stance, and any number of other situations that I just can't be bothered to list.

jet
2.5 / 5 (8) Jun 19, 2008
"It has also not been *proven* that cigarettes cause cancer"

so using your logic if we ended cigarettes there would be no cancer (note you did not say lung cancer or emphysema so can I make your over reaching statement to mean all cancer?

The logical progression would be that it we all became Luddites and went back to the earth like noble savages there would be no change in the temp of the earth ever.. does the term interglacial period mean anything to you ?
Glis
2.6 / 5 (5) Jun 19, 2008
I like how D666 denounces personal attacks yet uses them and sarcasm constantly.

This following is in no way meant to say anything about global warming, but to point out how easily we are manipulated.
Bush was originally against GW in order to get the environmentalists all fired up to get data for it, and they did. Then, he turncoats and is suddenly for it? The man who still insists Iraq had WMDs and there are little brown men trying to kill us... Someone as bullheaded as him does not change stance like that. The only reasonable explanation is that he was for it from the get-go and used the environmentalists to make his argument for him, knowing they would disagree with his standpoint. If he came out originally and said 'The planet is warming. We need carbon taxes!' we would all be screaming conspiracy now.
Modernmystic
3.7 / 5 (3) Jun 20, 2008
You know what I find really amusing here is that no matter how hard D666 pushes his religion on the rest of us NOTHING will be done to reduce CO2 emissions in the countries where it matters most. Fortunately people aren't willing to slit their "economic" throats over someone else's pet theories...never have NEVER will.
CHCB
4 / 5 (4) Jun 20, 2008

It has also not been *proven* that cigarettes cause cancer, that evolution actually happens, that Relativity is a reality, or any other number of silly comparisons I could come up with.


Your analogies are flawed, as evolution and the cigarette/cancer links are derived from observable and meaningful data. The current global warming projections, on the contrary, are based on computer models of an incredibly complex system using date from a sample so infinitesimally small as to be utterly meaningless (less than 200 years of climate data). Even the most empirically sound statement made by global warming adherents, that global temperatures have trended upward since 1850 has been challenged by a recent study of temperature monitoring sites.

Even IF global warming is happening as quickly AND for the reasons cited, the trillions of dollars we will spend in knee-jerk reactions (such as corn ethanol subsidies) could be employed to save millions of lives by addressing current, measureable problems with available solutions, such as disease and diet deficiencies.