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A Swift Kick in the Ice

Posted on 19 February 2011 by Rob Honeycutt

Commenting in the trenches of the climate change blogosphere I find a large number of people who lack very basic understanding about Arctic Ice.  While I'm not an expert in the field I have managed to learn a few things with regards to why Arctic ice is an important issue.  There are a few misconceptions that require a "swift kick in the ice."

When learning about these issues myself I came upon a question that I could not immediately answer.  We know that water vapor is a strong greenhouse gas.  We know that warmer air holds more moisture than cold air, in fact, to the point where the Antarctic is one of the driest deserts on the planet.  So, how does this jibe with the idea of polar amplification, the idea that the poles will warm faster than the rest of the planet on average?  The climate models tell us that the poles will warm faster, and the model results are proving true now. Why would the poles warm faster if there is so little water vapor in the air?

Fig 1  -  Surface Temperature Map for Jan 2011 (Source: GISS)

The first answer comes by way of looking at a surface temperature map (Fig 1).  What we find is that the north and south poles are not warming equally.  In fact, the term "polar amplification" is better described by saying "Arctic amplification."  If we look out to the end of the century there is anticipated to be amplification in the south as well but most of the warming will take place in the north.

But that still leaves us with, why?  The Arctic gets cold too, therefore is drier than the equator.  Why would the equator not warm faster?  

Fig 2  -  Orbital tilt through the year

Pretty much everyone knows that these basic very important facts about the north pole:

  1. The ice at the pole is covering the Arctic ocean.  It's sea ice.
  2. Both poles are mostly dark half the year and mostly light half the year.

These two very basic aspects of the Arctic make it special in terms of climate change form the reason why Arctic Amplification is happens and is so important.

Each year the ice of the Arctic thaws back to a minimum extent during the late summer, usually some time in September.  Then it freezes back each winter.  This is obviously because summer months are warmer and winter months are colder.  

The Battle of Albedo

Now I'll beat you up with the concept of "albedo."  Albedo is the effect where light colored surfaces reflect light and dark colored surfaces absorb light. Think of it as white pavement or black pavement.  Black pavement is always going to scorch your bare feet more than white pavement in the noontime sun.  Dark surfaces absorb more heat from the sun.  Light surfaces reflect more light away and absorb less heat.  

Fig 3  -  Albedo effects (source: wikipedia)

As you can see from Figure 3, the albedo of fresh snow is dramatically different from water - it's much more reflective.

In the winter the Arctic sea is almost completely frozen over but this doesn't matter a lot because there is little sun shine for half the winter and even no sun shine at all for several months of the year.  There is no albedo effect at all during this part of the year.

In the summer months, though, the story is the opposite.  If the Arctic Sea is covered with ice in the summer - as it has been dating back perhaps thousands, to millions of years - the incoming sunlight is mostly reflected back to space without adding any heat to the Earth.  But, as ice melts back, as is happening today, the summer sun is absorbed by the darker open sea exposed by the disappearing ice.  

The open water absorbs more and more heat during the extended daylight of the summer months until winter comes again, when the Arctic Sea freezes.  But because of warming the ice is also losing its capacity to freeze back to previous levels.  This is what is meant by a feedback.  Less ice makes warmer water, which makes thinner ice, which melts easier, which makes warmer water… and so on.

 Fig 4  -  2007 Summer sea ice minimum (source: NSIDC)

This also points out why the sea ice in the Antarctic is less important and generates less warming.  The Antarctic is a land mass 1.5 times the size of the United States.  Each winter sea ice develops around the Antarctic continent but thaws back mostly to the coast each summer.  There it can go no further.  The continent is almost completely covered in snow year round so the south pole maintains its high reflectivity during the summer months.

Something to be wary of is people who point to very select years or short time periods to say the ice is not melting.  You have to look at all the data to see the full picture.  The full picture of the Arctic clearly shows a rapid decline of ice both in extent (area) and volume (total ice).  Some people will also tell you that ice is growing in Antarctica.  That's true and false.  Winter sea ice extent is increasing slightly, but the land based ice, on the whole, is melting.  And as we understand above, winter sea ice extent is not going to have any effect because there is little or no sun in the winter.

When you take a moment to step back from the dusty battle taking place on climate issues sometimes you gain a little perspective.  I've actually learned quite a lot doing battle in the blogosphere trenches.  On occasion I get a boot on the derriere that forces me to try to better understand the arguments on both sides of the issue and learn more about what scientists are trying to tell us. 

It's not a pretty battle, and you have to bust ice to really get down to the truth.

-  -  -  -  -  -  

For the most up to date and accurate information about snow and ice issues you can visit the NSIDC, the National Snow and Ice Data Center.

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Comments 201 to 214 out of 214:

  1. RW1... I apologize for taking this thread off topic here but I have some more questions.

    So, on one hand we have some 10 thousand-odd climate scientists (not sure what the number actually is) and dozens of the most prestigious scientific organizations on one hand.

    On the other hand we have maybe a dozen or so top level scientists (Lindzen et al) who have put forth alternative theories.

    There is the possibility that the larger groups have made the mistake. Or there is the possibility that the smaller group is making the mistake.

    Laying aside any given actions that should be taken, who are you more willing to bet your children's future on? Are you really willing to bet that so many scientists are somehow pulling a ruse, ignoring some elemental aspects of science, in order to support their preferred conclusion?
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  2. Rob Honeycutt,

    "I apologize for taking this thread off topic here but I have some more questions.

    So, on one hand we have some 10 thousand-odd climate scientists (not sure what the number actually is) and dozens of the most prestigious scientific organizations on one hand.

    On the other hand we have maybe a dozen or so top level scientists (Lindzen et al) who have put forth alternative theories.

    There is the possibility that the larger groups have made the mistake. Or there is the possibility that the smaller group is making the mistake.

    Laying aside any given actions that should be taken, who are you more willing to bet your children's future on? Are you really willing to bet that so many scientists are somehow pulling a ruse, ignoring some elemental aspects of science, in order to support their preferred conclusion?"


    I'd respond, but the moderator is deleting my posts, so I'm done here. You're asking good questions, BTW.
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  3. @RW1
    "Good question. In short, yes. I think in essence they are mostly guessing and/or only looking for and interpreting data in ways that support enhanced anthropogenic warming because that is what their financiers are more or less looking for them to 'discover'."

    Oh yeah, unlike your denialist mates, who are often *proven* to be financed by the Fossil Fuel Industry. Are you suggesting that Arrhenius & all the other physicists & climatologists over the whole of the 19th & 20th centuries were also just trying to show 'what their financiers are more or less looking for them to discover'? If so, then that's a conspiracy with one *hell* of a lag time. With the sentence above, you've pretty much proved that you're not only a denier, but also a bit of a simpleton to boot. If these are the best "arguments" you can come up with to 'debunk' climate change, then its no wonder you probably spend most of your time hanging out with PopTech, Monctkon & Anthony Watts!
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  4. Marcus (RE: 203)

    Someone asked me a direct question and I answered it.

    I'm basing my conclusions on logic and evidence - not who has financed who.
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  5. "On the other hand we have maybe a dozen or so top level scientists (Lindzen et al) who have put forth alternative theories."

    In fairness, they don't even have alternative *theories*-they have *hypotheses*-ones which haven't even been supported by additional research. Lindzen's "Iris Effect", for example, has yet to receive any support from actual observations of cloud behaviour. Its not looking good for the Denialist Cult right now.
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  6. RW1 - what I want to see is your evidence. Your logic so far has been based on invalid assumption.

    If you want to talk science, then please go to appropriate thread and we can try to continue. Very important - have you got your head around Ramanthan and Coatley 1978? Science of Doom has some excellent aids to understanding the RTEs but discussions about where the 3.7W/m2 etc is going to be pointless without grasping these at some level.
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  7. RW1: Not really. The physics of GHGs absorption are pretty well understood and quantified, as is the aggregate measured response of the system to forcing power (i.e. the gain of the system). The issue boils down to the net feedback operating on the system. The large amount of positive feedback need for AGW is the extraordinary claim that requires extraordinary proof. I don't dispute there is likely some effect - just that the amount is too high.

    So, by your own words you have no problem with GHG physics. As for climate sensitivity and feedbacks I was going to recommend the thread, "Working out climate sensitivity from satellite measurements", but reading through it I see you have already been taken to task on your misunderstandings quite well. It also seems in that thread that you also seem to ignore the plethara of peer reviewed literature and care to learn no "real science".

    Again I'll ask you, list your sources that back up your claims for a large positive feedback nullifying the GHG forcings. You know to do this you also have to deny the 5 major global temperature measurements (GISS, HadCrut3v, NCDC, RSS & UAH) that all show significant warming is happening.

    Also, you seem to be drifting off topic, there are more appropriate threads concerning feedbacks and forcings.
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  8. "Someone asked me a direct question and I answered it.
    I'm basing my conclusions on logic and evidence - not who has financed who."

    Yes, & your answer proves you to be a conspiracy theorist-not much better than a Young Earth Creationist or a 9/11 Troofer. I'm sorry, but *when* have you ever proven that your conclusions are based on "logic & evidence"? You've just revealed that you believe the whole of Climatology is just one long conspiracy-all financed by an as yet undisclosed group/individual. I see nothing logical or evidence based in that. My conclusions, by comparison, are based on reading *all* the available data, & using a mind that's been *trained* to read scientific papers (as I have a B.Sc (Hons) & work in a scientific field) to determine whether what they're saying is accurate or not. What the majority of the world's climatologists fits in with *everything* we know about how the world works-& has yet to be overturned by any competing hypotheses/theories-whereas the Denialists (like yourself) rely mostly on conspiracy theories & straw-man arguments. So, based on that choice, guess which side I'm going with?
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  9. RW1 @189, George White's arguments are rife with errors. (There was going to be a third and fourth post on his errors, but the page containing his essential argument is currently down.) One of the most egregious is the halving of the reduction in outgoing radiation due to IR gases. This is very easily verified for your self using the modtran model hosted by David Archer. This is an obsolete model available on the public domain, but it still shows a change in TOA OLR of -3.17 w/m^2 for a doubling of CO2 from the default settings. Note, that is the reduction in the Outgoing Longwave Radiation, it is not "the amount of IR radiation captured" or some other vague term designed to confuse. Based on this model, with 375 ppm CO2, approx 287.8 w/m^2, while with 750 ppm, approx 284.7 w/m^2 leaves the planet.

    As I said, this is an obsolete model, built in the early 1990's. More recent and more accurate models have since been built which refine the prediction to 3.7 w/m^2, a result consistent by satellite observations.

    When you have a dispute between a single amateur and the whole of the world's scientific community on a single well known value, it is not "critical thinking" to simply accept that word of the amateur. It is gullibility. It is no less gullibility if people cannot find published papers establishing some thing taught in first year climate science courses. For some reason, journal editors are loathe to accept papers that merely reestablish some well known result (unless it is done with a novel and interesting method).

    However, in this case it is not true that nobody could point you to an academic source for this value. They, after all, will have pointed you to the IPCC at minimum. That you and George White do not understand the definition of "atmospheric forcing" is not their fault. Nor is it "critical thinking". Rather, it is simple ignorance, and in anyone who has read up on climate science as you claim to have done, willful ignorance.
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  10. Marcus @ 205... Just trying to extend a little in order to build a connection. I actually believe that the hypotheses being put forth from the skeptic side are not consistent with observations. Low climate sensitivity for Lindzen just doesn't jibe with paleoclimate reconstructions. And there are various fundamental problems for GCR's being a serious driving force in climate.
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  11. HR - why would the fact that natural forcing have acted in the past (and act today) give anyone palpitations? Someone is denying it? However, the natural forcing that might have resulted in ice-free pole are NOT acting now.
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  12. Tom Curtis (RE: 209),

    Let's take this over to the appropriate thread.
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  13. Tom Curtis (RE: 209),

    What thread do you want to take it to? Moderators - any suggestion?
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    Moderator Response: [DB] KR has suggested the How sensitive is our climate? thread, while RickG has suggested the Measuring Earth's energy imbalance thread. Depending on your desired focus, pick the more appropriate one. Or use the search function to find one you feel most appropriate. Thanks!
  14. The correct thread is this one.

    The issue I was raising was not climate sensitivity, or the Earth's energy balance. It is that RW1's self proclaimed "critical thinking" is neither.

    I am not going to bury that point by pretending that whether or not the doubling CO2 would have an atmospheric forcing of 3.7 w/m^2 or 1.85 w/m^2 (as Geoge White would have us believe) is a matter open to discussion. The later opinion is simply an error, an error only possible in some one who does not even know the meaning of "atmospheric forcing".

    The correct response in this situation is not to discuss this on some other thread but for RW1 to admit the error, and to stop swallowing uncritically any sort of nonsense churned out by denier hacks.
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  15. RW1 - I have responded Climate sensitivity is low
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  16. HR @152, pointing out a limited truth without context in such a way as is likely to deceive is a form of lying. People who do it are said to be telling half truths, and are appropriately described as disingenuous.

    Had you pointed out that there are natural forcings that have caused polar amplification in the past (half the truth), but that those forcings are now acting in opposition of polar amplification (the whole truth), then I would not have called you disingenuous. But had you done that, of course, you would not have opened up any doubt as to whether the current arctic amplification is natural, or anthropogenic in origin.
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  17. I'm not an expect on this either:
    The reason for warming at the poles so strong:

    The temperatures are much colder at the poles, and this actually puts the black body radiation curves peak closer to CO2's absorption band.

    So the CO2 driven greenhouse effect occurs more strongly near the surface.

    ---
    Is this correct?
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    Moderator Response: [Daniel Bailey] This is discussed both here at SkS and here by Serreze et al 2009.
  18. For S. Dobbs:
    http://scholar.google.com/scholar?q=arctic+amplification
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  19. For the curious:
    "Data released March 1, 20011 by NOAA’s National Snow and Ice Data Center shows that the seasonal extant of Arctic sea ice at the end of February, 2011, stood at a record low, well below the prior record set in 2005 and almost 3 million square kilometers below the average for that winter date, when sea ice is usually within days of its greatest seasonal extant for the year."
    Pretty much a new minimum maximum (say that 3 times fast):


    Gray line indicates 1979 to 2000 average extent

    I'd say that's a swift kick in the...ice.

    [ -Edit: fixed dates per guidance from michael sweet below; thanks michael! ]

    The Yooper
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  20. DB,
    I am not sure where you got your quote from. At the NSIDC website, they say the record was set in 2005, not 2007. They report the extent for the month of February to be record low, tied with 2005. (IJIS shows 2006 as the record low month. It is unusual for NSIDC and IJIS to differ).

    The current maximium is lower than the record low on IJIS, but NSIDC has not reported the maximium for the year yet. It is below, but very close to, the previous low maximum. A few cold days would put it over the previous record while a few warm days would set it under. At Cryosphere Today the Sea Ice Area (area is a little different from extent) is declining and the high would be a record low if there is not a major shift in the next few days.

    In any case, the ice is certainly not showing any signs of recovery this year.

    Your point is certainly correct: that's a really swift kick in the ice.
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  21. Sorry, michael, for my confusion. You are 100% right. Just me being a dumb*** & not reading the actual news release from here but relying upon a 2nd-party news service (here). Probably just a typo, like 2350 becoming 2035...

    I plead laziness originating from our public school systems and too many teachers from the "flower power" generation. ;)

    Thanks for being gentle,

    The Yooper
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