Sea Ice North: The new field of ice-free Arctic Ocean science
Sea Ice North: The new field of ice-free Arctic Ocean science
I recently read a paper in Physics Today entitled The Thinning of Arctic Sea Ice by R. Kwok and N. Untersteiner. (Nice essay by Untersteiner) This paper was written for a general scientist audience, and provides a good summary of the state of the science. The primary focus of the article is on understanding the small change to the surface energy balance required to explain the increased rate of sea ice melt in the summer. Some time ago I wrote a few blogs on Arctic sea ice; they can be found here and this one is most relevant: Sea Ice Arctic.
When the IPCC Assessment Report was published in 2007 the Arctic sea ice was in visible decline. In the summer of 2007 there was a record decline that caught the attention of both climate scientists and the broader public. As suggested in Kwok and Untersteiner immediately following the release of the 2007 IPCC report papers started to appear about how the IPCC synthesis had underestimated the melting of both sea ice and ice sheets. Much of this underestimate could be summed up as simplistic representation of the dynamics of ice melting. For example, brine-laden sea ice floating in salty sea water turns over. Snow gets on the top. It melts, then there are puddles and ponds that can flow down into ice. Simplistically, and I am a simpleton, it’s like a pile of ice cubes sitting in a glass versus stirring those ice cubes, or blowing air over the ice, heat gets carried around and ice melts faster.
The presence of large areas of open ocean in the Arctic is new to us. It motivates new research; it motivates claims to newly accessible oil, gas, and minerals; it motivates new shipping routes; it suggests changes in the relationships of nations; it motivates the development of a military presence. (All things Arctic from the Arctic Council) The natural progression of scientific investigation starts to explore, describe, and organize what is to us modern-day humans: a new environment, new ecosystems, and new physical systems. For example, the Mackenzie River now delivers a massive pool of fresh water into the ocean. Fresh and salt – big differences to flow in the ocean because the density is different; big difference to the formation of ice because the freezing temperature is different; and big differences in the plants and animals in the water.
Compared with trying to attribute the contribution of global warming to a particular weather event, it is easier to link the recent, rapid decrease of sea ice to a warming planet. The freezing, melting and accumulation of ice require persistent heating or cooling. It takes a lot of heat for a sustained period to melt continental-size masses of ice. Historically, the sea ice that was formed in the winter did not melt in the summer and there was a buildup of ice over many years – it accumulated; it stored cold. Around the edges of this multi-year ice are areas where the sea froze and melted each year. The melting of multi-year ice, therefore, represents the accumulation of enough heat to counter years of cold. The movement, poleward, of the area where ice freezes and thaws each year is the accumulation of spring coming earlier. The requirement for energy to persist and accumulate to affect changes in sea ice reduces the uncertainty that is inherent in the attribution of how much global warming has impacted a particular event.
Understanding the detailed mechanisms that provided the heat to melt the ice remains a challenge. (This is the real point of in Kwok and Untersteiner) We know it takes about 1 watt per square meter of energy to melt that much ice that fast. This could be delivered by the Sun, transported by the air, by the ocean, by warm water from the rivers of Canada and Siberia, by snow – yes, snow is energy. Once the ice is gone in the summer, then the ocean can absorb heat from the Sun. If there is growth of phytoplankton or zooplankton, then they might enhance the absorption of energy – yes, life is energy. Ocean acidification might change. The natural question that arises – do these processes that are active in this new environment work to accelerate sea ice melting or might they contribute to freezing of water. What are the local feedbacks? (This is above – see below.)
Another study that is of interest is the paper in Geophysical Research Letters, Recovery mechanisms of Arctic summer sea ice, by S. Tietsche and colleagues. This is a model study. With a model the scientist owns the world and can prescribe what it looks like. In these numerical experiments, the Arctic is prescribed with no ice. Then whether or not the ice recovers is explored. In these studies the ice does recover. The ocean does indeed take up extra heat in the summer, but it gives it up quickly in the fall. This is followed by the formation of first year ice in the winter. The ice-albedo feedback that might let the ice melt runaway is limited. Tietsche et al. conclude that it is not likely that Arctic sea ice will reach a tipping point this century.
This does not mean that summer ice loss will decrease. This does not mean that there will not be huge changes in the Arctic. This only says that it still gets cold in the winter.
Models: One of the things I like about the Kwok and Untersteiner paper is their brief discussion of models. They point out that none of the models available for the 2007 IPCC assessment were able to predict the rate of sea ice decrease. Looking forward, they state that the model projections for 2060 range from no sea ice in September to more sea ice than is observed today. The Tietsche et al. paper is a focused model experiment – not a climate projection. It is also a model result that, perhaps, helps to understand the differences in the 2060 projections. That is, how is the recovery of sea ice in the autumn represented in the projection models?
A couple of other points: First, the amount of energy needed to cause the observed melting in sea ice is 1 watt per square meter. If you calculate the amount of energy in the different factors at play in melting of sea ice, then the numbers are 10s of watts per square meter. As suggested above, there are many reservoirs of energy – the Sun, rivers, etc. So when we look at the different ways 1 watt per square meter can be delivered to the sea ice, then there are several paths. The existing models tell us that with the increased heat due to greenhouse gases, energy gets delivered to the Arctic and sea ice melts. The existing models say that there might be several different paths; it is likely, that several of them operate at different times. The second point: Of course the Tietsche et al. paper will enter as an isolated contribution to the political argument, Arctic “death spiral” – as will those of accelerated melt, New warning on ice melt.
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Figure 1: Simplistic summary of Arctic sea ice
Useful links
Recent sea ice trends
Sea ice data
Rood’s Blogs on Ice
Reader Comments
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:-) I wouldn't go quite that far--denialists are hurting themselves along with everyone else, after all--though I completely understand your frustration. But don't be too hard on yourself; it's not that you haven't done a fantastic job of patiently and thoroughly explaining the overwhelming science backing up AGWT. It's just that some people long ago convinced themselves that the planet isn't warming, so absolutely no amount of science--no matter how patiently and thoroughly it's explained to them--will ever sway them from their sad concrete shoes of denial.
I'm sorry for your feelings of insignificance relative to an entire university. Wish there was something I could do to help.
atmoaggie- note that in Mike's post, he posted blogs to refute peer reviewed papers, once again.
If blogs are considered "real science" then a children's picture book must be considered to be advanced reading.
How do you figure that a downward slope of about 45 degrees is a flat line?
The ice increased in extent slightly yesterday then decreased slightly in extent today, making a flat line.
http://www.wunderground.com/blog/MichaelSTL/show. html
Looks like Mike has been banned, after the death threat he gave me...
I can remember him with this quote.
I don't see where it increased in extent slightly yesterday then decreased slightly in extent today.Show me where that is?
Cyclone,
This graph uses a 5 day running mean, wheras IJIS-JAXA uses a one day running mean. You can note the flattening off of sea ice even in that graph.
And A%M is a good school. The opportunity for a great education is presented, though not all choose to take full advantage of it.
lol. this is what I mean by you believing only natural oscillations and co2 dictate global temps.
There's other factors, so please quit acting like these are the only two. CO2 feedbacks were also likely different than they are today.
if co2s feedbacks cancel out the ghg warming, why are we still warming? Why has co2 levels correlated so well with temps the last half million years?
You're still yet to prove that CO2's feedbacks cancel out the warming created through ghg warming.
with regards to oscillations more frequently in their positive phase, that is likely an effect of gw. gw isn't caused by natural oscillations, only regional warming is. oscillations affect heat distribution. they can alter the total heat of the system slightly, but the negative phase does the opposite. the only reason an oscillation would be in one phase longer than the other is if some sort of global climate change was occurring.
and by galie there is
That's unfortunate, because there are some other non-banned blog members on here who literally contrite nothing to the blog. Michael was certainly not one of those members.
The difference is some people who don't "contrite" to the blog don't attack others and belittle them. It is in the rules.
TheGh0st Is michaelSTL people. He used that name when his other one was banned a while ago.
Anyway, back to the matter at hand: I see that even the Catholic Church is coming around to the undeniable truth of GW:
"A report commissioned by the Vatican's Scientific Panel, the Pontifical Academy of Sciences doesn't mince words: it urges the world to act quickly and strongly to address climate change."
"It says: 'humans must act decisively now to avert a coming crisis.'
"'We have entered a new geologic epoch that began when the impacts of mankind on the planet became a major factor in environmental and climate changes.'
"'We call on all people and nations to recognize the serious and potentially reversible impacts of global warming caused by the anthropogenic emissions of greenhouse gases and other pollutants,' it says. 'If we want justice and peace, we must protect the habitat that sustains us.'"
A little late, but good: every voice helps. Too, the Vatican has a lot of pull, so who knows?
idk who's more to blame here, the blog members or the admins, but either way debates on this blog and most blogs on wunderground are awful. I suppose its that way on most internet forums and boards, but it seems especially bad on here.
Reported.... try to be civil, as hard as that may be, Mike.
I'm saving this quote...
I disagree. I actually thought that he had interesting stuff to post, but whatever respect I had for him was lost in the quoted section above....
When you have over half of the people who post on this blog ignored then you shouldn't get close to getting yourself banned. I ignore the people who just want to argue and attack and look I'm not banned. You really want to know when the arguing went this way you can look at SSI and Jflorida for that one.
I took a screen capture of it just incase it got deleted or nobody could of quoted it.
Thank you. FYI his other handle got banned as well.
http://www.wunderground.com/blog/TheGh0st/show.ht ml
When the oceans are warm, they tend to release more co2. When they are cold, they tend to suck in more co2. This is what was being observed during our periods of interglacials and Ice Ages. The oceans are huge sinks of co2, and since there was nothing or no one adding co2 to the atmosphere during the period of Ice Ages, this is what happened all the time.
Obviously, if we are still warming, then a natural cause must be causing it, and the overall Global Warmth correlates with the AMO in quite a lot of places, statistically significant in some spots.
You are mistaken that the oscillations are an index of GW. They are not driven by GW at all. They are driven by natural changes in the THC which alter oceanic currents, and change the AMO from negative to positive. Overall, the AMO has been trending more and more positive, and as we have discussed earlier, a AMO creates faster ice melt at the Arctic, and since there has been an upward trend in the index of the AMO, the Arctic is gaining OHC.
If all clouds were to be removed, then energy coming in increases from 239 Watts per Meter squared, or (239 w/m^2) to 288 w/m^2. This difference can be calculated by subtracting the final result from the initial result, which is 49 w/m^2. Cloud Cover also impacts the Infared Light escaping from the Earth. With Cloud Cover the Energy leaving the Earth is 234 w/m^2. This is increased to 266 w/m^2. This difference is 32 w/m^2. When you subtract the Energy Coming in minus the energy leaving, you get an energy imbalance of 17 w/m^2. This is an indicator that since there is more energy coming into the climate system, than there is leaving, the decrease of clouds creates warming of the planet, since there is more heat coming in, than there is coming out (Hartmann, 1994).
Here is what I noted from an earlier post:
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From Climate4you.com
Higher up, part of the lifted water vapour will condensate to form small water droplets and clouds, whereby latent heat is released, causing warming and additional convection and cloud formation.
When Water Vapour condenses to form clouds, it is NOT there anymore! This explains the "flat" trend observed in NOAA satellite data. Again, one miscalculation in the co2 feedback system could spell doom for the CAGW hypothesis.
Deductable Reasoning is how you get to this conclusion that co2 makes more clouds.
co2 warming makes increased evaporation due to warmer waters---->This creates increased Water Vapour-------->And Increased Water Vapour means higher amounts of clouds, if there were no other factors involved in GCC formation.
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In a perfect world, if there were no GCRs or Oceanic Oscillations impacting GCC, then you would notice a clear correlation between GCC (which I have already shown has the same amount of cooling as co2 does warming) and co2 concentrations.
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