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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Interesting image there Cyclone. How do you plan to implement these tunnels?
NOAA Global Climate Change Indicators
National Oceanic and Atmospheric Administration
National Climatic Data Center
Many lines of scientific evidence show the Earth's climate is changing. This page presents the latest information from several independent measures of observed climate change that illustrate an overwhelmingly compelling story of a planet that is undergoing global warming. It is worth noting that increasing global temperature is only one element of observed global climate change. Precipitation patterns are also changing; storms and other extremes are changing as well.
How do we know the Earth's climate is warming?
Thousands of land and ocean temperature measurements are recorded each day around the globe. This includes measurements from climate reference stations, weather stations, ships, buoys and autonomous gliders in the oceans. These surface measurements are also supplemented with satellite measurements. These measurements are processed, examined for random and systematic errors, and then finally combined to produce a time series of global average temperature change. A number of agencies around the world have produced datasets of global-scale changes in surface temperature using different techniques to process the data and remove measurement errors that could lead to false interpretations of temperature trends.
The warming trend that is apparent in all of the independent methods of calculating global temperature change is also confirmed by other independent observations, such as the melting of mountain glaciers on every continent, reductions in the extent of snow cover, earlier blooming of plants in spring, a shorter ice season on lakes and rivers, ocean heat content, reduced arctic sea ice, and rising sea levels.
Right. But where it impacts where the warmer water is, (Equatorial Pacific or not) and it determines whether we have more frequent El Ninos or more La Ninas.
You are correct that Japan had a hot summer, but that is one event. If what you say is true, then Japan should constantly see above average temperatures. Nope.
Japan had a very cold January, and had an unusual late season cold spell and snowfall.
Now why could that be? I had mentioned that the reason for why the PDO and AMO impact the continents was the onshore flow. It is also impacted by another factor: The Jet Stream.
QUOTE
Jet streams are fast flowing, narrow air currents found in the atmospheres of some planets, including Earth. The main jet streams are located near the tropopause, the transition between the troposphere (where temperature decreases with altitude) and the stratosphere (where temperature increases with altitude).[1] The major jet streams on Earth are westerly winds (flowing west to east).
http://en.wikipedia.org/wiki/Jet_Stream
So perhaps Japan doesn't feel the impacts of the -PDO due to the Jet Streams carrying air currents from West to East.
From post 200.
That sentence is technically incorrect. The PDO can not be "cooling off" since it is not a measurement of temperature. The PDO is measured the same way a velcoity time graph in physics would be measured.
Note that while the velocity time graph in this image shows a decrease near the end, the position time graph continues to increase. The position time would be the temperature and the velocity time would be the PDO.
Does the isotopic signature of the aerosoles show that they were mainly man made? If so, man made aerosoles played a part helped the cooling from 1940-1975.
If aerosoles are still here, then why aren't we seeing Global Cooling? The rate of increase in Carbon Dioxide did not increase much, so why did it start warming if the PDO is not to blame, and there are still aerosoles?
LOL accelerating Global Warming by cooling... classic.
That's the 64,000 dollar question.I am first trying to get interest of a university to computer model them first. Then from there who knows what may happen.
Snowlover did you read this post yet?
Nope, I did not. Thank you for refering me to it.
I have to go at the moment, so I will respond to your post tomorrow. :-) Goodnight.
I think the PDO does have an effect on overall cloud cover which in turn affects the heat loss to space, thus I'm not sure that it has no effect of the overall heat content. However this is as of yet poorly understood, so neglecting this for now I guess I would otherwise agree here. Our ability to measure the overall heat content of the climate system is unfortunately far inferior to our ability to measure the temperature at the surface*, which is why surface temperatures are usually what is emphasized when discussing warming. The PDO does seem to correlate there, which is why I think a portion of the warming seen by the methods that we can measure could be due to natural changes in the distribution of heat. If this is true, discounting this will lead to overestimating future warming.
*I realize we also measure temperatures in the upper ocean as well, but the resolution of these measurements is far less than surface temperature measurements, albeit far greater than those of the deep ocean.
Chemical Found in Crude Oil Linked to Congenital Heart Disease: Fetal Exposure to Solvents May Damage Heart
ScienceDaily (Apr. 30, 2011) %u2014 While it may be years before the health effects of the 2010 oil spill in the Gulf of Mexico are known, a new study shows that fetal exposure to a chemical found in crude oil is associated with an increased risk of congenital heart disease (CHD).The study, presented on April 30 at the Pediatric Academic Societies (PAS) annual meeting in Denver, also showed that babies who had been exposed in utero to a chemical found in cleaning agents and spot removers were at increased risk of CHD.
Environmental causes of CHD have been suspected, and animal studies have suggested certain chemicals may cause CHD, a problem with the heart's structure and function due to abnormal heart development before birth.
"Congenital heart disease is a major cause of childhood death and life-long health problems," said D. Gail McCarver, MD, FAAP, lead author of the study and professor of pediatrics at the Medical College of Wisconsin and Children's Research Institute, Milwaukee. "Thus, identifying risk factors contributing to CHD is important to public health."
Dr. McCarver and her colleagues sought to determine whether human fetal exposure to solvents is associated with increased risk for CHD. The researchers tested samples of meconium, or fetal stool, from 135 newborns with CHD and 432 newborns without CHD. Meconium has been used to assess fetal exposure to illicit drugs such as cocaine. Seventeen compounds were measured in meconium samples using methods that detect very low levels of chemicals.
Additional data collected included race of the mothers and infants, family history for CHD, and maternal alcohol, tobacco, vitamin and drug use.
Infants with chromosomal abnormalities known to be linked to CHD, and babies of diabetic mothers were excluded from the study.
Results showed that 82 percent of infants had evidence of intrauterine exposure to one or more of the solvents measured.
Among white infants, but not black infants, fetal exposure to ethyl benzene was associated with a four-fold increased risk of CHD. In addition, exposure to trichloroethylene was associated with a two-fold increased risk for CHD among white infants and an eight-fold increased risk among black infants.
"This is the first report that exposure to ethyl benzene, a compound present in crude oil, was associated with CHD," Dr. McCarver said. Humans also can be exposed to ethyl benzene through inhalation of motor vehicle emissions, gasoline pump vapors and cigarette smoke.
"The association with ethyl benzene exposure is concerning, particularly considering recent oil spills," she said. "However, additional confirmatory studies are needed."
The study also adds to existing concerns about trichloroethylene (TCE). "This is of particular importance because TCE is a commonly used degreasing agent, which also is present in many cleaners and spot removers. TCE also has been the most common chemical identified around hazardous waste sites," Dr. McCarver said.
"Limiting known maternal exposure to this compound during early pregnancy appears prudent, particularly among those at increased CHD risk," Dr. McCarver concluded.
Link
I consider myself to be one of the most prominent skeptics on this forum, and unlike MichealSTL, I actually have a conscience of how I treat other people.
My favorite quote so far from him is this quote:
you clearly can't read at all and flunk at reading comprehension even if you can
I suspect that there will be more to come, since he seems to be the type of person that has no regard to other people that disagree with him.
However, I disagree that all CAGW Proponents are nasty like Michael. There are plenty of good CAGW Proponents who I have come to respect, all from another forum that cyclonebuster also participates in. Wayne is one from a forum that is nice, and debates respectfully. I also have come to respect TomTaylor from this board.
I agree completely. The oceans storing heat and retaining that stored heat is also why the SSTs do not vary as much as the land based temperatures.
Right. The PDO and AMO do not have as many complicated climatic feedbacks as co2 induced warming.
Right, but where the redistributed heat is, is quite significant. The Equator sees the same average temperature, with little to no deviation from normal. When the oceanic oscillations focus the redistributed heat near the equator, to form more powerful El Ninos, it has the same impact, as if the Arctic were to have an entire anomaly of say, +20 Degrees C.
More El Ninos=More warming.
co2 induced warming is not quite as simple. You have complicated cloud and water vapour feedbacks, that I believe we will not be able to master in the near future. It has been documented that negative feedbacks could abolish any warming by co2.
http://www.aai.ee/~olavi/cejpokfin.pdf
QUOTE
the variability of the air temperature at these
stations during the last centuries shows that the influence of growing CO2
concentration in the atmosphere has been totally eliminated by the system’s negative
feedback.
http://www-eaps.mit.edu/faculty/lindzen/comirishy p.pdf
Right, but they can focus the heat where it can impact the Global Temperature significantly. It is well documented that El Nino and La Nina dominate Climate Variability.
I have no idea why I am up at 2 am, but I should be heading to sleep now. :) Goodnight.
Well, I wish the best for you and your tunnels, Cyclone. :)
The main point of that post was that all those ocean cycles affect global temperatures only because we measure surface temperatures. However, the total heat content of the ocean and atmosphere is not affected by these cycles at all. This is because these cycles have no effect on the total heat content and only have an effect on the distribution of this heat.
Co2 on the other hand does affect the total heat content of the earth. Therefore, our global temperature graph trends can be blamed on oscillations, however true global warming (by measurement of total heat in the oceans and atmosphere, NOT just the surface) can NOT be blamed on oscillations.
That is precisely what ghgs do. They alter the total heat of the planet by trapping extra heat which would otherwise escape. Oscillations do nothing to the total heat of the system (except maybe altering cloud cover as sirmaelstrom mentioned, but the relationship there is not at all understood).
Gulfstream Kinetic Energy can snub out or smooth out those oscillations like an accumulator does all while lowering the total net global heat content and at the same time produce an enormous amount of electrical power. What geo-engineering project can do better than that right now?
So where is the video?
.21c is not fudging.Even if they are .21c lower than what Jeff claims they are they are still to high. See what the tornadoes did in Alabama because of those higher than normal temps.? Imagine how much worse those tornadoes could have been if the temperature was .21 c greater? What is your point? Temps are still to high.
.21c is not that far off. what's your point?
One year, warm or cold does not make for a trend in the GOMEX SST anomalies, I agree. Last year the GOMEX was very cold due to troughing in the E made by El Nino, -AO, -NAO, and this year, the GOMEX has above normal SSTs due to a SE Ridge that is common during a La Nina.
Nothing unusual, yet the CAGW Proponents will try and harp that this has "never been seen before."
Imagine if the Great Blizzard of 1888 happened this year... LOL the CAGW Proponents would be all over that.
.21c is near a record. What's your point?
Until they realize that the Earth goes through cycles I'm not sure it is even worth discussing it with them.
Isn't the GOM part of the Atlantic ocean and is included in world ocean temperatures? So it stands to reason why the temps are rising in the GOM also.What does "What's Up With That" have to say about this. Does it know more than NOAA on this?
Global Upper Ocean Heat Content is Rising
While ocean heat content varies significantly from place to place and from year-to-year (as a result of changing ocean currents and natural variability), there is a strong trend during the period of reliable measurements. Increasing heat content in the ocean is also consistent with sea level rise, which is occurring mostly as a result of thermal expansion of the ocean water as it warms.
Time series of seasonal (red dots) and annual average (black line) of global upper ocean heat content for the 0-700m layer since 1955. More information: BAMS State of the Climate in 2009.
BTW I bet they have to rescale this chart also upwards again this year.
The total ocean heat content would be the same, however, the total land based heat content would increase, which in turn would rapidly warm the Arctic, due to the warmer than normal Ocean Currents, and in turn would melt the Arctic, and the Arctic would warm faster than everywhere else, due to the patches of ocean that would appear, due to melted ice, warming the Arctic, and adding Heat to the Earth's Global Heat Budget. So effectively, the oceans indirectly add more heat, due to the Arctic Albedo, or "reflectance."
It is also important to note that there has been no increase in OHC over the past several years.
http://www.npr.org/templates/story/story.php?stor yId=88520025
QUOTE
Some 3,000 scientific robots that are plying the ocean have sent home a puzzling message. These diving instruments suggest that the oceans have not warmed up at all over the past four or five years. That could mean global warming has taken a breather. Or it could mean scientists aren't quite understanding what their robots are telling them.
This is puzzling in part because here on the surface of the Earth, the years since 2003 have been some of the hottest on record. But Josh Willis at NASA's Jet Propulsion Laboratory says the oceans are what really matter when it comes to global warming.
In fact, 80 percent to 90 percent of global warming involves heating up ocean waters. They hold much more heat than the atmosphere can. So Willis has been studying the ocean with a fleet of robotic instruments called the Argo system. The buoys can dive 3,000 feet down and measure ocean temperature. Since the system was fully deployed in 2003, it has recorded no warming of the global oceans.
/QUOTE
I agree, but disagree. I agree that if there were NO possible Climate Feedbacks, yes, Man has the potential to warm Earth with doubling co2 by 1 Degree F. However, this is not nearly the case, and there are known documented Climate Feedbacks with doubling of co2. One of those is increased evaporation. The evaporated water condenses to form clouds.
When the total amount of cloud cover goes up, the temperature comes down. This is one of the most prominent negative feedbacks co2 has to deal with if it wants to warm the Earth 1 Degree F when there are doubled amounts of co2.
And as seen here,
http://www.aai.ee/~olavi/cejpokfin.pdf
QUOTE
the variability of the air temperature at these
stations during the last centuries shows that the influence of growing CO2
concentration in the atmosphere has been totally eliminated by the system's negative
feedback.
/QUOTE
The clouds' negative feedback are enough to cancel co2 warming all together. co2 induced warming in the past had negative feedbacks to deal with, it has negative feedbacks to deal with now. That is why in the paleoclimatological data, the co2 is more than ten times as high as current co2 concentrations, but we were in the midst of an Ice Age.
You are correct- but you have stated what they do when there are no climate feedbacks.
Oscillations
With regards to the 3,000 robots (ARGO project), here is a direct quote from their website
They've only been collecting data since late 2003. Your NPR news report was issued in 2008. If anyone honestly thinks 4 years is enough time to note climate trends, they're fooling themselves.
link
But if you really think 4 years is enough time, here's the graph they produced (in black)
looks like warming if anything.
And you claim oscillations don't have any net change on the total heat content of the oceans, but do increase total land heat. What is your proof of this?
Feedback loops
About climate feedbacks of CO2, you point out a negative feedback loop (graeter cloud coverage), but you leave out the fact that water vapor itself is a greenhouse gas, which causes warming.
You also leave out many other positive feedback loops (melting arctic, methane release from deep seas, methane release from arctic tundra, desertification, deforestation, etc, etc).
The subject of feedback loops in climate changes is very complicated. To go outright and claim that the net effect of CO2's feedback loops is cooling is foolish.
In summary...
Oscillations are not proven to have any net change on the total heat of earth.
CO2 feedbacks are not understood well enough to claim that they cause net cooling.
Data results from year 2008 and after
In an article from November 5, 2008, Josh Willis states that the world ocean actually has been warming since 2003 after removing Argo measurement errors from the data and adjusting the measured temperatures with a computer model his team developed.[3][10]
Here is a graph with the 2008/2009 Argo network data included.[15]
Link
Yea, well your leaving out a bit of key info from that wikipedia page, let's not cut stuff out.
Here's the full quote from wikipedia's ARGO page on Data Results:
Basically data from 2003-2006 showed only a slight, but really insignificant cooling. However, the method used to determine that was apparently faulty, and so, when they published the data from 2003-2008 using proper methods, they found a slight warming.
For anyone who doesn't like wikipedia, you can find all the same info from ARGO's page
Link
Correct it is old hat now! We already knew this years ago! They are just trying to pull the blind over our eyes and sugar coat it.
To expound on what you posted so others don't get hood winked by the playboy readers here.
Ocean temperature and heat content
Over the past 50 years, the oceans have absorbed more than 80% of the total heat added to the air/sea/land/cyrosphere climate system (Levitus et al, 2005). As the dominant reservoir for heat, the oceans are critical for measuring the radiation imbalance of the planet and the surface layer of the oceans plays the role of thermostat and heat source/sink for the lower atmosphere.
Domingues et al (2008) and Levitus et al (2009) have recently estimated the multi-decadal upper ocean heat content using best-known corrections to systematic errors in the fall rate of expendable bathythermographs (Wijffels et al, 2008). For the upper 700m, the increase in heat content was 16 x 1022 J since 1961. This is consistent with the comparison by Roemmich and Gilson (2009) of Argo data with the global temperature time-series of Levitus et al (2005), finding a warming of the 0 - 2000 m ocean by 0.06°C since the (pre-XBT) early 1960's.
You should try reading NOAA literature at some point in your life!
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