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Earth Science

Arctic Ice Extent Understated Because of "Sensor Drift" 823

dtjohnson writes "The National Snow and Ice Data Center (NSIDC) has been at the forefront of predicting doom in the arctic as ice melts due to global warming. In May, 2008 they went so far as to predict that the North Pole would be ice-free during the 2008 'melt season,' leading to a lively Slashdot discussion. Today, however, they say that they have been the victims of 'sensor drift' that led to an underestimation of Arctic ice extent by as much as 500,000 square kilometers. The problem was discovered after they received emails from puzzled readers, asking why obviously sea-ice-covered regions were showing up as ice-free, open ocean. It turns out that the NSIDC relies on an older, less-reliable method of tracking sea ice extent called SSM/I that does not agree with a newer method called AMSR-E. So why doesn't NSIDC use the newer AMSR-E data? 'We do not use AMSR-E data in our analysis because it is not consistent with our historical data.' Turns out that the AMSR-E data only goes back to 2002, which is probably not long enough for the NSIDC to make sweeping conclusions about melting. The AMSR-E data is updated daily and is available to the public. Thus far, sea ice extent in 2009 is tracking ahead of 2005, 2006, 2007, and 2008, so the predictions of an ice-free north pole might be premature."
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Arctic Ice Extent Understated Because of "Sensor Drift"

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  • by mcfatboy93 ( 1363705 ) on Thursday February 19, 2009 @09:04AM (#26915241) Homepage

    instead of using sensors that move and 2 systems that don't work why not try just taking pictures or using those weather satalite things to look at whats ice and whats not

  • Historical error (Score:4, Interesting)

    by Potor ( 658520 ) <farker1@gmai l . c om> on Thursday February 19, 2009 @09:10AM (#26915281) Journal

    Am I to understand that they will continue to measure (and predict) ice conditions based on less accurate sensors simply because these measurements tally better with older measurements, which themselves are less accurate?

    Or have I missed something?

  • by dov_0 ( 1438253 ) on Thursday February 19, 2009 @09:20AM (#26915337)
    Unfortunately that seems to be the way of a lot of science today. Carbon dating is another minefield that comes to mind. The current mindset seems to take on popular theory and interpret it as fact. The scarier and more apocolyptic, the better. Very post-modern. Anything that doesn't fit that 'fact' has a fight ahead to even get published.
  • Bigotry? (Score:3, Interesting)

    by paulthomas ( 685756 ) on Thursday February 19, 2009 @09:41AM (#26915543) Journal

    I like how you liken "climate change deniers" to religious bigots. "Religious zealots" would be more appropriate, and they exist on both sides.

    Yeah, this is the basic idea of how science is supposed to work, but that's not the point that comes across in your post. The parent post is a troll.

  • Re:Oh gosh. (Score:3, Interesting)

    by hattig ( 47930 ) on Thursday February 19, 2009 @09:44AM (#26915577) Journal

    A lot of them infect techy websites like dailytech for no apparent reason apart from one of "their kind" posts carefully selected anti-global-climate-change stuff. Mostly single data points, rather than overall trends of course. They don't have science on their side.

    Of course it is good if they exist to ensure that the science is rigourous. Sadly they go beyond that, to actually trying to recruit believers to their cause - all too easy in a world addicted to cars - like a religion. They come up with alternate theories which the science doesn't support, much like intelligent design, creationism, etc. Considering the eventual outcome of being wrong in all this, it is highly irresponsible of them, and I hope that if things do go tits up in a pear shaped bowl that they are the ones made to pay.

    Not that the extremists on the other side help. Doom-mongering damages your cause, all in the name of sensationalism. Just let the science speak for itself.

  • by Anonymous Coward on Thursday February 19, 2009 @09:50AM (#26915631)
    My father is an environmental engineer. He cleans up some of the stupid crap we have done over the past hundred years. We were having a talk about global warming years ago, before it was a big buzzword. He said to me: "Be careful listening to the global warming experts. If they have devoted their career to global warming and if it turns out not to be true, they don't just lose their job they lose their field of expertise."
  • by elrous0 ( 869638 ) * on Thursday February 19, 2009 @10:11AM (#26915841)

    I once worked with an environmental professor who could put the harshest fire-and-brimstone preacher to shame in her millennialist proclamations of doom (her grad students could too). All she was after was grant money, and she wasn't above going to the press and using the Chicken Little routine in order to drum up support for her latest grant proposal. I frequently had to write press releases for her that I was ashamed of (if you even hinted to her that she should tone it down and stick to reasonable statements she would literally freak out like a madwoman). From that moment I met her, I adopted a very skeptical view of the whole global warming "crisis" and its proponents.

    Science is nowhere near as "hard" as people think. Too many scientists are way more interested in grant money and in their personal reputations than in the validity of their conclusions.

  • Re:Oh gosh. (Score:3, Interesting)

    by wisty ( 1335733 ) on Thursday February 19, 2009 @10:31AM (#26916121)

    Deniers don't just use a single data point. They use every year since 1998 - and point out that every one of those years is cooler than 1998. That's a lot of data points, right? All those cool years (compared to 1998) can't be outliers, can they?

  • A Modest Proposal (Score:2, Interesting)

    by Solarch ( 1473575 ) on Thursday February 19, 2009 @10:35AM (#26916171)
    I have a very simple proposition that might shed some light on the argument about sea ice melting and cities going underwater.

    Take a clear plastic disposable cup and fill it to any level you desire with water and any amount of ice cubes (4-5 would be plenty) you desire. Mark the level of the water. Let the cup sit out (covered if you really wish) until the ice melts. Mark the level of the water.

    The results should surprise you, if you think that melting sea ice will put Florida and NYC and other low-lying areas underwater.
  • Re:Oh gosh. (Score:1, Interesting)

    by Anonymous Coward on Thursday February 19, 2009 @10:42AM (#26916277)

    Unfettered. Got it.

    So, would you advocate removing all controls on lead, SO2, and CFC emissions?

    Oh, and a couple of followup questions:
    1) where in your local area would you prefer the next landfill and hazardous waste site to be, and how much will you be willing to increase your taxes and/or trash disposal fee in order to pay for its siting and transportation of your waste to that location?
    2) how much more than the current price would you be willing to pay for access to clean water?
    3) do you hope to have grandchildren someday, and what lifestyle would you like them to be able to experience when they reach adulthood?

  • by oodaloop ( 1229816 ) on Thursday February 19, 2009 @11:38AM (#26917093)
    Yeah, overall I'd say it's a mixed bag. I was highly skeptical myself until recently when I started reading more about it. I wanted to see the evidence that the Earth was in fact warming. I wanted to see the evidence that said warming was Anthropogenic. And I wanted to see the evidence that this was going to be a bad thing if true. Most of what you see in the mainstream media is how we produce CO2, and how CO2 can heat the planet. But they don't link the two to show that the amount we produce does and has heated the planet and they don't talk specifically about how even a small increase can be disastrous other than a rise in ocean levels. I've read a few books on it, and I'm no longer skeptical and accept that we are causing a rise in temperature on Earth, and that this is generally very very bad.

    Despite what this article says, Arctic ice has decreased significantly in recent years. Satellite imagery from as recent as 1979 shows enormously more ice than we see today.
  • Re:Rocket science? (Score:4, Interesting)

    by AmericanGladiator ( 848223 ) on Thursday February 19, 2009 @12:15PM (#26917679)

    And your argument is nothing more than an ad hominem attack on the poster, which is equally worthless.

    Let me argue his point from a logical perspective.

    Let's assume that a certain political party makes its hay by promising things to the underclass. They make promises to those who have very little and so the promises don't have to be very big to make them happy.

    Now assume that this party wants to stay in power and have a greater number of votes for them in future elections. This party would therefore welcome the idea of a larger underclass. They would potentially do things that would weaken the middle class so that there is a larger lower class and and smaller middle class. If they can put things in place like cap & trade systems for energy emissions, where the wealthy will remain wealthy, but the middle class will suffer, they come out ahead.

    It's not so much paranoia in my opinion, but a shrewd understanding of how politicians love power and want to stay in power. In this case, I am referring to democrats as they (to me), seem to want to enact policies that hurt the middle class. Global warming is something they have championed because it helps to further their agenda, not because it necessarily is good for the environment.

  • by Freedryk ( 117435 ) on Thursday February 19, 2009 @12:18PM (#26917717)

    I'm a climate scientist--a modeler, in fact. I know C, C++, Fortran, Python, Java, bits of Perl and PHP. I figure I could get a job at Amazon on Google or Microsoft or some other big software shop and be making over $100k. I could certainly do better than what my salary has been: $25k for 2000-2006 (grad school), and for 2007-8 it was $40k (postdoc). Let's say I got a job for $50k/yr--that would be an extra $170k I would have made over the last 8 years.

    Let me tell you buddy, I'm not in this for the money.

    And if someone could find compelling evidence that indicated global warming wasn't happening, that would be welcomed by the climate science community. New evidence that overturns an old understanding is the holy grail of science.

  • Re:Rocket science? (Score:5, Interesting)

    by wytcld ( 179112 ) on Thursday February 19, 2009 @12:21PM (#26917767) Homepage

    Unfortunately climate data and predictions are apparently more motivated by political beliefs and biases than hard facts.

    That's an empty assertion, apparently motivated by the conflict between the conclusions from overwhelming climate data and the writer's ideology.

    Where is the sociological data to support it? All these claims about "political beliefs and biases" among climate scientists are working backwards from a desire to reject the conclusions of science to ad hominem attacks on the scientists themselves - attacks which make presumptions about the politics of scientists which are naive in the extreme. A great many - perhaps most - scientists are not political at all. They're too busy with their science to worry about politics outside of their own university departments, and anyway consider most politicians and commentators a bit too stupid to concern themselves with one way or the other.

    So where's your data on "political beliefs and biases" among climate scientists? As most of them are funded by governments, can you show an example from any scientific community of a pronounced pattern of biting the hand that feeds it? Consider the scientists funded by drug companies. Do their results cut against their funders?

  • Re:Rocket science? (Score:1, Interesting)

    by 97cobra ( 89974 ) on Thursday February 19, 2009 @12:26PM (#26917815)

    The original scientist that found the link between DDT and egg thickness later proved that there was no link, his original research was flawed. He was then ignored since it didn't fit into the agenda of the environmental movement.

  • Re:Rocket science? (Score:1, Interesting)

    by Anonymous Coward on Thursday February 19, 2009 @12:29PM (#26917851)

    The fact that there are "Denialists", "Believers", "Supporters" and "Followers" makes this area of science look a lot like religion.

    More and more people are moving to aetheism, but there still seems to be an intrinsic human desire or need for spirituality. Without even realizing it, for many people the earth becomes their new god and environmentalism is their religion. Like any other religion, facts are less important than faith, they get offended if you question their faith and they are always trying to recruit new members.

  • by burning-toast ( 925667 ) on Thursday February 19, 2009 @12:37PM (#26917951)

    Hit submit too early. My point earlier was that the data should have been well vetted for and all of this shit done before reaching the public eye where "scientists" will prop it up (for either "camp") in the evidence of the month club.

    I'm not denying global climate change. I'm just sick of people who think they have "proved" everything, but then admit they can't point at anything concrete and agreed upon on a large enough scale to really show anything significant.

    - Toast

  • Re:Rocket science? (Score:1, Interesting)

    by Anonymous Coward on Thursday February 19, 2009 @12:45PM (#26918079)

    Certain countries in the world could use some mosquito control.

    And they do. In fact, India uses DDT for agricultural purposes.

    I never understood this "OMG they banned DDT" bullshit. The Stockholm Convention, which bans most uses of DDT, explicitly allows public health uses of DDT. It's used worldwide for exactly this purpose.

    Perhaps the answer wasn't to eliminate its use but to manage it to limit the harm it could do.

    Yes. That would be wonderful. And that's exactly what happened. DDT is restricted to "vector control", which limits its environmental impact and (perhaps more importantly) slows the spread of DDT-resistant mosquitoes. So what's your problem?

    I guess blaming people for something they didn't actually do is one way to get your rocks off.

  • by mosb1000 ( 710161 ) <mosb1000@mac.com> on Thursday February 19, 2009 @01:08PM (#26918431)
    "Science isn't an exact science"

    Forgive me if I'm wrong, but isn't exactness the whole point of science? Doesn't science rely on controlled experimentation to conclusively disprove or fail to disprove a hypothesis? Has "pop science" become the new science? Is it now considered acceptable to reach a conclusion without the support of controlled experimentation, but still call it a scientific conclusion? How is this new breed of science any different than guessing?

    I think the true scientists among us need to find a new word to describe what they do.
  • Re:Rocket science? (Score:3, Interesting)

    by jellomizer ( 103300 ) on Thursday February 19, 2009 @01:30PM (#26918767)

    Real Environmentalists take actions into a balance. Everything thing you do has a trade off. Should the president take Air Force 1 to North Dakota to sign an environmental bill. To fly to ND he probably used more Carbon then most of use do in a year. However by going there in a backdrop of wilderness his point to the public about the emphasis he put in the bill not just a daily signing that he does during the day. How much Wilderness will we use up for a new Public Transportation Infrastructure, Will Clean energy methods need mining of hazardous materials or making of non-recyclable or non-biodegradable materials. By consuming less will we hurt the economy more, and cause people the unability to afford more efficient methods. Will recycling programs use more energy and different pollution then what you get by not.

    It is all about balance and choosing the right trade offs.

  • Re:Not consistent? (Score:3, Interesting)

    by Moryath ( 553296 ) on Thursday February 19, 2009 @01:57PM (#26919189)

    Think about what makes you so angry about climate science; chances are good that it's all about politics. You believe what's politically convenient and then try to justify it.

    I didn't believe James Hansen in the 1970s when he was predicting the next ice age, and I don't believe him any more today now that he's completely changed his mind. I have laughed at the various terms thrown about by sensationalist news anchors for decades (in the late '70s-early '80s it was "thermal inversion", in the mid-90s they came up with "ozone action day", etc). Every time this stuff comes around, it's the same old crap: bad science, sensationalism, and hysteria rather than a reasoned, thoughtful "this is what we know and this is what we need to improve based on X checked and re-checked data."

    If you calm down and think about it rationally, I think you'll conclude that the science is actually pretty solid.

    I've seen the "science." See also: Selection Bias and Confirmation Bias. The so-called "scientists" aren't objectively checking the data, or even checking up on each other, and that's a major problem. No, the "science" is not "solid."

    Present me with some solid science, and I'll be happy. On the other hand, don't expect me to believe in something backed up by less reliable "science" than Xenu, E-Meters and L. Ron Hubbard.

    Oh, and of course, consider the following question: why, for the past 10 years, have the news reporters been comparing temperatures and atmospheric levels to 1979? It's because 1979 was an unusually harsh cold snap. If you compare to the 1970s average, you get a different answer. Hell, if you compare to 1978 or 1980, you get a different answer - but those don't fit the "OMG the sky is falling global warming will kill us all" mass hysteria bullcrap they're pushing.

  • Re:Tosh. (Score:3, Interesting)

    by locofungus ( 179280 ) on Thursday February 19, 2009 @02:02PM (#26919267)

    But they strongly implied, if not stated out right, that the amount of ice would be significantly less in 2008. Turned out they were completely wrong.

    Are we reading the same article? In my version it says:

    Drobot predicts a 59% chance of a new record minimum this year

    As it happens, 2008 was the second lowest on record, despite a strong rebound during the winter months.

    http://gatewaypundit.blogspot.com/2008/02/brrrr-disappearing-arctic-ice-is-back.html [blogspot.com]

    Tim.

  • by WinPimp2K ( 301497 ) on Thursday February 19, 2009 @05:01PM (#26921745)

    "We stress, however, that this error in no way changes the scientific conclusions about the long-term decline of Arctic sea ice, which is based on the the consistent, quality-controlled data archive discussed above."

    Hmm...

    Algor: "Global warming is melting the arctic icecap. Our sensors show open Arctic Ocean.
    Duhfact: "Al, we have satellite imagery showing icecap where your sensors say there is open ocean"
    Algor: "Umm.. we have a little problem with sensor drift"
    Duhfact: "So, your statements about the melting of the icecap are incorrect?"
    Algor: "No, our 'sensor drift' just proves our point. Those sensors are drifting because of the ice cap melting"
    Duhfact: "Actually we have measurements showing increasing icecaps for the past five years"
    Algor: "Our drifting sensors have been drifting for at least 20 years so that just proves how much of the icecap has already melted"
    Duhfact: (head explodes)
    Algor: "And the science on this is in - no one disagrees with the conclusions".

    Their conclusion is consistent with a need for increased funding to continue to conclude that the icecaps are really melting. But, their data is anything but consistent and their "quality control" is somewhat more dubious than the "accounting controls" of Bernie Madoff.

After a number of decimal places, nobody gives a damn.

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