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
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I think Snowlover is Roy Spencer!
NOAA Scientist Rejects Global Warming Link to Tornadoes
A top official at the National Oceanic and Atmospheric Administration (NOAA) rejected claims by environmental activists that the outbreak of tornadoes ravaging the American South is related to climate change brought on by global warming.
Greg Carbin, the warning coordination meteorologist at NOAA%u2019s Storm Prediction Center in Norman, Oklahoma, said warming trends do create more of the fuel that tornadoes require, such as moisture, but that they also deprive tornadoes of another essential ingredient: wind shear.
%u201CWe know we have a warming going on,%u201D Carbin told Fox News in an interview Thursday, but added: %u201CThere really is no scientific consensus or connection [between global warming and tornadic activity]%u2026.Jumping from a large-scale event like global warming to relatively small-scale events like tornadoes is a huge leap across a variety of scales.%u201D
Asked if climate change should be %u201Cacquitted%u201D in a jury trial where it stood charged with responsibility for tornadoes, Carbin replied: %u201CI would say that is the right verdict, yes.%u201D Because there is no direct connection as yet established between the two? %u201CThat%u2019s correct,%u201D Carbin replied.
Formerly the lead forecaster for NOAA%u2019s Storm Prediction Center, Carbin is a member of numerous relevant professional societies, including the National Weather Association, the American Meteorological Society, the Union of Concerned Scientists, and the International Association of Emergency Managers. He has also served on the peer review committee for the evaluation of scientific papers submitted to publications like National Weather Digest and Weather and Forecasting.
This evaluation by a top NOAA official contradicted pronouncements by some leading global warming activists, who were swift to link this season%u2019s carnage to man-made climate change.
%u201CThe earth is warming. Carbon emissions are increasing,%u201D said Sarene Marshall, Managing Director for The Nature Conservancy's Global Climate Change Team. %u201CAnd they both are connected to the increased intensity and severity of storms that we both are witnessing today, and are going to see more of in the coming decades.%u201D
Bjorn Lomborg of the Copenhagen Consensus Center, an activist and author who believes industrialized societies expend too much money and energy combating global warming, instead of focusing on more immediate, and easily rectifiable, problems, doubted the tornadoes have any link to warming trends.
%u201CWe've seen a declining level of the severe tornadoes over the last half century in the U.S.,%u201D Lomborg told Fox News.%u201CSo we need to be very careful not just to jump to the conclusion and say, %u2018Oh, then it's because of global warming.%u2019%u201D
In fact, NOAA statistics show that the last 60 years have seen a dramatic increase in the reporting of weak tornadoes, but no change in the number of severe to violent ones.
For many, the high casualties of 2011 recalled the so-called %u201CSuper Outbreak" of April 1974, which killed more than 300 people. %u201CYou have to go back to 1974 to even see a tornado outbreak that approaches what we saw yesterday,%u201D W. Craig Fugate, administrator of the Federal Emergency Management Agency (FEMA), told Fox News.
Asked earlier, during a conference call with Alabama Gov. Robert Bentley about the possibility that climate change is playing a role in the tornado outbreak, Fugate shot back: "Actually, what we're seeing is springtime. Unfortunately, many people think of the Oklahoma tornado alley and forget that the Southeast U.S. actually has a history of longer and more powerful tornadoes that stay on the ground longer -- and we are seeing that, obviously, in the last week and yesterday.%u201D
Link
The jet sure wasn't slow yesterday. I think they are looking at what wind shear does in the subtropical jet over the oceans not over land. It is possible that while the shear in the tropical oceans decrease that this may cause the shear over land to increase. Any studies done on this?
Using a digital "Deep Siren" tactical messaging system and a simpler underwater telephone, officials from the Navy's Arctic Submarine Laboratory at the camp last Saturday were able to help the submarine find a relatively ice-free spot to surface and evacuate a sailor stricken with appendicitis.
The alternative could have been a ruptured appendix, or an emergency surgery on the table in the captain's dining room, said a relieved Dan Roberts, a senior chief and corpsman who handles the crew's medical needs. "It would have been rough."
The low-frequency system is built by Raytheon Co, which has been working on it for several years with $5.2 million in initial seed money from the Navy.
Raytheon is the latest player trying to tackle the persistent challenge of communicating with submarines while they are traveling deep under the sea to avoid detection. Past systems have proven too complicated, and too expensive.
The new system could revolutionize how military commanders stay in touch with submarines all over the world, allowing them to alert a submarine about an enemy ship on the surface or a new mission, without it needing to surface to periscope level, or 60 feet, where it could be detected by potential enemies.
At present, submarines use an underwater phone to communicate with associates on top of the ice or with other submarines, but those devices are little more than tin cans on a string and work only at shorter distances. Submarines can also trail an antenna once they surface to periscope depth, or around 60 feet, but that makes them easier to detect.
Captain Rhett Jaehn, the No. 2 official in charge of submarine operations and the officer in charge of the ice camp 150 miles north of Prudhoe Bay, said the Deep Siren was heavily used during the exercises and played a key role in facilitating the evacuation of the sick sailor.
Improving the ability to communicate with submarines at any depth and longer distances is a huge step forward, said Matthew Pesce, a former submariner who now works for the Arctic Submarine Laboratory, which organizes biannual ice exercises in the region, where submarines practice tactics and procedures.
Pesce is based in Hawaii, but joined the USS New Hampshire for the exercises as adviser for Arctic equipment and issues, including the Deep Siren system. He said the system worked well, but some transmissions did not come in completely, possibly due to the alignment of the submarine.
Dave Desilets, spokesman for Waltham, Massachusetts-based Raytheon, said Deep Siren had reached a technology readiness level of 7 on a scale of 1 to 9, and was ready to move into production, but did not yet have a production order in hand.
The new product, which includes separate laptop computers for sending and receiving, is already generating interest from foreign countries, and two foreign sea trials are planned this year, said Stephen Moynahan, a senior Raytheon engineer.
Moynahan came to the ice camp in early March to test how the system works under the ice canopy
where varying salinity levels and long ice keels distort how sound travels.
He said the sales prospects were promising, noting that Britain successfully tested Deep Siren in the Mediterranean last year, proving a range of more than 100 miles.
Raytheon also offers a variant with buoys that can be quietly deployed by a submarine in its waste discharge, waiting to surface until the submarine is far away, and then relaying messages via satellite link.
Moynahan said the new system, initially conceived by a Scottish submariner named Robert Kerr, provided only limited messaging ability, not bandwidth for transmitting huge chunks of data, but said its simplicity made it effective, especially in the current difficult budget environment.
"This is a really big deal. This is a game-changing technology," said Moynahan, who served as the rifleman guarding against polar bear attacks during a visit to the camp by Navy Secretary Ray Mabus and other top lawmakers and defense officials on Saturday. No bears turned up.
Pesce said the system helped the submarine find a place to surface since locating ice-free waters in the Arctic was a little like "looking upward through a straw," he said.
Wow, what a shock, empirical evidence strikes again.
Good Morning, TomTaylor!
1) Earth has generally warmed since the LIA, I agree,
2) Sea Levels have generally been rising, with a plateu in later data, I generally agree.
3) There is a problem with your third point. You ignore something that is known as Climate Feedbacks. Without any Climatic Feedbacks, the doubling effect of co2 is roughly 1 Degree F. However, co2 creates feedbacks. The Climate Models assume that most of the feedbacks from doubling co2 will be positive, so it has catacylsmic amounts of warming. Nope. co2 creates increased evaporation from the water to form clouds. Low Level Clouds have a net cooling impact.
Cosmic Rays also play a role in cloud formation. If the feedbacks (which we know little about) are all negative, it can hide all of the co2 induced warming.
Good Morning Mike!
Based off of that graph, it's hard to tell. If I were to guess, I'd say 55/45 Warm.
Dr. Spencer is without power in Alabama. FYI
There's an excellent article on Salon.com this morning talking about Texas Governor Rick Perry's call for a day of prayer to help end the drought. The writer says, "Calling for prayer while refusing to recognize the EPA's regulations on greenhouse gases seemed like an act of willful ignorance, as if Texas were sticking its fingers in its ears and humming as loud as it could to drown out what amounts to a warning of a future climate-change-induced catastrophe."
But then he calls for an end to just ridicule alone (even if denialist tenets are just that):
"The bigger issue is that, as the effects of climate change become more tangible, weather more unpredictable, and ordinary conditions more disastrous, progressives will have to offer more than sniggers to those who feel threatened by changes they don't understand.
"Of course, as those of us who are pro-science argue, the changes are in fact perfectly understandable if you just look at the evidence on climate change. But we know there are lots of reasons why people don't trust science, from the psychological (we tend to valorize information that confirms our existing beliefs and rationalize away information that doesn't) to the political (oil companies have a vested interest in marginalizing real climate science and disseminating misinformation). Of course, better science education wouldn't hurt -- and by "better," I mean education that doesn't openly flout scientific consensus on evolution and climate change, as Texas education policy now does."
It really is a good article, and something even deniers can agree with, at least in part.
http://www.salon.com/news/science/?story=/politic s/war_room/2011/04/29/battistoni_science
Psst: it's not "sifting through the archives" to present an article published just over an hour ago. Just sayin'...
BTW: I cleared the improperly-translated HTML character entities within a minute of posting; if you'd like some help cleaning them up in your quote, feel free to drop me a WU Mail and I'll be more than happy to walk you through the process. ;-)
Perhaps that will reduce his carbon footprint.
At any rate, I have yet to see a single article or blog post stating that this week's devastating tornadoes were a direct result of GW/CC. Not even on any of the wacko conspiracy sites. However, I have read numerous posts mentioning that this week's super outbreak (for that's what it was, in every sense of the word) can be looked at--along with the increasing, and increasingly severe/extreme, weather events around the planet--as a fairly clear indicator that, so far, climate scientists have been pretty much correct in stating that just such things would occur as the planet warms.
And, frankly, I don't believe we've really seen anything yet.
The planet is heating up--quickly--and our burning of fossil fuels is largely to blame. That's the increasingly solid theory, and no amount of obfuscation, misinformation, disinformation, double-speak, political rhetoric, or red-faced denial is going to change that.
So are you for the use of Gulfstream Kinetic Energy to get us out of this mess such as Arctic Ice melting,hurricane damage,tornado damage,severe weather,warming oceans,rising ocean PH,rising sea levels,coral bleaching and off of fossil fuels?
"And, frankly, I don't believe we've really seen anything yet."
You are correct we are at the tip of the iceberg like the polar bear is.
Tornado counts are going up over the years. No one, except the most devout, has any expectation that CO2 nor temperature changes are the cause. Population growth and changing observing systems have a huge role in these numbers. (Phunny how changing observation systems aren't well-considered in most other time-series of phenomena).
http://www.ncdc.noaa.gov/sotc/tornadoes/2010/13
Strong tornadoes (F3+) appear to decreasing in direct opposition to the causes of increased overall counts. The trend is clearly not on an increase. To say that strong tornadoes would increase with AGW is to assume the effect hasn't begun yet. (Which would be in opposition to all of the other trends that are assumed to be a consequence already.)
Though more structures are in the way of strong tornadoes, changes in code and building practices could play a role, as well. (EF scale determined by damage done, a partly subjective determination, at best, and very difficult to keep consistent when the type of structures and the number of structures change significantly).
http://www.ncdc.noaa.gov/sotc/tornadoes/2008/13
(Note: would have grabbed a younger version, but the NCDC doesn't make a plot of only the strong tornadoes any more for some reason.)
So, where is climate change? Those mentioning that this week's super outbreak can be looked at as a fairly clear indicator that climate scientists have been pretty much correct in stating that just such things would occur as the planet warms are apparently in direct opposition to observations.
Try hard enough and you can see whatever you want to see. And many really, really want to see tornado super outbreaks increasing as a result of CO2, sick as that sounds.
That's for March through August what does it look like from January to December?
Mornin to you
I see you agree with what I said too...good to hear. About the climate models and they're failure to predict feedback loops, time will tell what happens
How tornado numbers relate to a warmer world is not understood well at all. Dr masters has a blog post on it from a while back basically saying that under a warmer world there would be less sheer (due to the decrease in difference in temps from the equator to the poles) but greater CAPE values (due to more available moisture from greater evaporation in a warmer world).
Is that over oceans and land?
Live Science Article...
Tornadoes whipped up by wind, not climate: officials
In the aftermath of a severe tornado, owner Frank Evans stands on the rubble that was the Quik Pawn Shop in Tuscaloosa, Alabama. US meteorologists warned Thursday it would be a mistake to blame climate change for a seeming increase in tornadoes in the wake of deadly storms that have ripped through the US south.
AFP - US meteorologists warned Thursday it would be a mistake to blame climate change for a seeming increase in tornadoes in the wake of deadly storms that have ripped through the US south.
"If you look at the past 60 years of data, the number of tornadoes is increasing significantly, but it's agreed upon by the tornado community that it's not a real increase," said Grady Dixon, assistant professor of meteorology and climatology at Mississippi State University.
"It's having to do with better (weather tracking) technology, more population, the fact that the population is better educated and more aware. So we're seeing them more often," Dixon said.
But he said it would be "a terrible mistake" to relate the up-tick to climate change.
The tornadoes that ripped through the US south this week killed over 250 people, in the worst US weather disaster in years, with residents and emergency workers sifting through the rubble on Thursday.
Violent twisters that famously rip through the US south's "Tornado Alley" are formed when strong jet winds bringing upper-level storms from the north interact with very warm, humid air mass from the Gulf of Mexico, said David Imy from the NOAA Storm Prediction Center in Norman, Oklahoma.
On Wednesday, a particularly potent storm was whipping up around the heart of that tornado-prone corridor where the states of Arkansas, Oklahoma, eastern Texas and northwest Louisiana meet, noted Kristina Pydynowski, a senior meteorologist at the AccuWeather.com website.
Sparking the severe thunderstorms from that point was the much warmer air arriving from the south, over the tropical Gulf. The combining winds at differing altitudes, said Pydynowski, created "significant twisting motion in the atmosphere, allowing the strongest thunderstorms to spawn tornadoes."
Such a mixture would not be prevalent along the US eastern seaboard, so rough weather in that region Thursday would not also spawn tornadoes, at least on the same scale, she said.
Craig Fugate, administrator of the Federal Emergency Management Agency (FEMA), also dismissed Thursday climate change as a factor in the deadly tornadoes: "Actually what we're seeing is springtime," he said.
"Many people think of Oklahoma as 'Tornado Alley' and forget that the southeast United States actually has a history of longer and more powerful tornadoes that stay on the ground longer."
Wednesday's deadly tornadoes, according to Imy of the National Oceanic and Atmospheric Administration, were unusual for being "long track," meaning they were on the ground for a longer period of time than usual -- in this case, roiling across the land for 30 miles (48 kilometers) or more.
An average track would be less than five miles, said Imy.
However, the stronger-than-usual tornadoes affecting the southern states were actually predicted from examining the planet's climatological patterns, specifically those related to the La Nina phenomenon.
"We knew it was going to be a big tornado year," he said. But the key to that tip-off was unrelated to climate change: "It is related to the natural fluctuations of the planet."
----
MichaelSTL would love that last sentence. He doesn't believe their should be natural fluctuations.
He made a post on the last blog on how la nina increases the likelihood of severe weather over the us.
It is also bad for hurricanes strikes on the US. Correct?
(And he and I actually agree on something, to a degree.)
Oh! Come on MichaelSTL. Don't underestimate the transfer of energy in the Gulfstreams kinetic energy to restore our climate back to pre-industrial revolution temperatures. It is what our planet so desperately needs right now to remove fossil fuel.
It is not in opposition to this is it?
Really the Earth doesn't go through cycles?
You don't think observation methods have improved dramatically over the time period represented in that graph?
Since the late 1960s yes.
LOL Well said Mike.
Mythical? LOL! I built a scale model that works. No longer a myth is it?
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