UPDATE: Perhaps in response to criticism here, MIT has changed the press release wording. See below.
From MIT, now if they could work the wind patterns in, as NASA suggests, we might have a clearer picture of why the Arctic summer sea ice extent has changed.
Ocean currents play a role in predicting extent of Arctic sea ice
CAMBRIDGE, Mass. — Each winter, wide swaths of the Arctic Ocean freeze to form sheets of sea ice that spread over millions of square miles. This ice acts as a massive sun visor for the Earth, reflecting solar radiation and shielding the planet from excessive warming.
The Arctic ice cover reaches its peak each year in mid-March, before shrinking with warmer spring temperatures. But over the last three decades, this winter ice cap has shrunk: Its annual maximum reached record lows, according to satellite observations, in 2007 and again in 2011.
Understanding the processes that drive sea-ice formation and advancement can help scientists predict the future extent of Arctic ice coverage — an essential factor in detecting climate fluctuations and change. But existing models vary in their predictions for how sea ice will evolve.
Now researchers at MIT have developed a new method for optimally combining models and observations to accurately simulate the seasonal extent of Arctic sea ice and the ocean circulation beneath. The team applied its synthesis method to produce a simulation of the Labrador Sea, off the southern coast of Greenland, that matched actual satellite and ship-based observations in the area.
Through their model, the researchers identified an interaction between sea ice and ocean currents that is important for determining what’s called “sea ice extent” — where, in winter, winds and ocean currents push newly formed ice into warmer waters, growing the ice sheet. Furthermore, springtime ice melt may form a “bath” of fresh seawater more conducive for ice to survive the following winter.
Accounting for this feedback phenomenon is an important piece in the puzzle to precisely predict sea-ice extent, says Patrick Heimbach, a principal research scientist in MIT’s Department of Earth, Atmospheric and Planetary Sciences.
“Until a few years ago, people thought we might have a seasonal ice-free Arctic by 2050,” Heimbach says. “But recent observations of sustained ice loss make scientists wonder whether this ice-free Arctic might occur much sooner than any models predict … and people want to understand what physical processes are implicated in sea-ice growth and decline.”
Heimbach and former MIT graduate student Ian Fenty, now a postdoc at NASA’s Jet Propulsion Laboratory, have published the results from their study in the Journal of Physical Oceanography.
An icy forecast
As Arctic temperatures drop each winter, seawater turns to ice — starting as thin, snowflake-like crystals on the ocean surface that gradually accumulate to form larger, pancake-shaped sheets. These ice sheets eventually collide and fuse to create massive ice floes that can span hundreds of miles.
When seawater freezes, it leaches salt, which mixes with deeper waters to create a dense, briny ocean layer. The overlying ice is fresh and light in comparison, with very little salt in its composition. As ice melts in the spring, it creates a freshwater layer on the ocean surface, setting up ideal conditions for sea ice to form the following winter.
Heimbach and Fenty constructed a model to simulate ice cover, thickness and transport in response to atmospheric and ocean circulation. In a novel approach, they developed a method known in computational science and engineering as “optimal state and parameter estimation” to plug in a variety of observations to improve the simulations.
A tight fit
The researchers tested their approach on data originally taken in 1996 and 1997 in the Labrador Sea, an arm of the North Atlantic Ocean that lies between Greenland and Canada. They included satellite observations of ice cover, as well as local readings of wind speed, water and air temperature, and water salinity. The approach produced a tight fit between simulated and observed sea-ice and ocean conditions in the Labrador Sea — a large improvement over existing models.
The optimal synthesis of model and observations revealed not just where ice forms, but also how ocean currents transport ice floes within and between seasons. From its simulations, the team found that, as new ice forms in northern regions of the Arctic, ocean currents push this ice to the south in a process called advection. The ice migrates further south, into unfrozen waters, where it melts, creating a fresh layer of ocean water that eventually insulates more incoming ice from warmer subsurface waters of subtropical Atlantic origin.
Knowing that this model fits with observations suggests to Heimbach that researchers may use the method of model-data synthesis to predict sea-ice growth and transport in the future — a valuable tool for climate scientists, as well as oil and shipping industries.
“The Northwest Passage has for centuries been considered a shortcut shipping route between Asia and North America — if it was navigable,” Heimbach says. “But it’s very difficult to predict. You can just change the wind pattern a bit and push ice, and suddenly it’s closed. So it’s a tricky business, and needs to be better understood.”
Martin Losch, a research scientist at the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, Germany, says the feedback mechanism identified by the MIT group is important for predicting sea-ice extent on a regional scale.
“The dynamics of climate are complicated and nonlinear, and are due to many different feedback processes,” says Losch, who was not involved with the research. “Identifying these feedbacks and their impact on the system is at the heart of climate research.”
As part of the “Estimating the Circulation and Climate of the Ocean” (ECCO) project, Heimbach and his colleagues are now applying their model to larger regions in the Arctic.
This research was supported in part by the National Science Foundation and NASA.
Written by: Jennifer Chu, MIT News Office
###
Note:Sloppy reporting by MIT, not citing the paper title or DOI. It doesn’t seem to be online yet here at the journal:
http://journals.ametsoc.org/loi/phoc
Doesn’t have this paper, in monthly or early edition that I can find by searching for the author names.
UPDATE: Perhaps in response to the complaint I sent to the PR officer and the author, they have now changed the text to read:
Before:
Heimbach and former MIT graduate student Ian Fenty, now a postdoc at NASA’s Jet Propulsion Laboratory, have published the results from their study in the Journal of Physical Oceanography.
After:
Heimbach and former MIT graduate student Ian Fenty, now a postdoc at NASA’s Jet Propulsion Laboratory, will publish a paper, “Hydrographic Preconditioning for Seasonal Sea Ice Anomalies in the Labrador Sea,” in the Journal of Physical Oceanography.
I’d say the traditional method.
Your link is full of so many logical fallacies it’s hard to know where to begin.
Hindcasting a random walk is not much of a challenge. It’s forecasting one that eludes us.
Well Henry…Mommy and Daddy decide to play hide and seek in their bedroom. Then about 9 months later a little boy gets born and they decide to call him Anthony.
Jeff says
I’d say the traditional method…
Henry says
So, that would be a chance of 1 out of about 50 million or so other sperm cells from one ejaculation?
(I had not even thought of that one yet….)
Come on Jeff, in the minute you took to react, you could not possibly even have read all that I had said.
.Anyway..either way, we were still talking arctic ice here, so we are completely off topic here.
I think we are given a link now where we could discuss a bit further…
(I challenge you….)
http://wattsupwiththat.com/2012/11/22/from-history-the-proclamation-of-thanksgiving/
Robertvdl says
Could someone please explain the hot spot near the Svalbard archipelago
So it has nothing to do with the fast drifting multi year sea ice going south in the Greenland Sea
pulling in ‘warm’ water from more southern latitudes
http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticsst_nowcast_anim365d.gif
http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticict_nowcast_anim365d.gif
some sort of local ocean current.
Plusk says:
November 22, 2012 at 2:03 am
@Philip Bradley
Of course, ice forms everywhere, where temperature is lower than melting point of ocean (salty) water, no matter it’s -2 or -40 Celcius degrees. But there is ENORMOUS effect on the thickness of the ice formed. The result of few degrees higher average temperature is much thinner ice formed.
The empirical data from the last decade shows older ice melts significantly faster than newer ice. If you are correct then we should be seeing the opposite. Newer ice (measured by extent) melting faster. This isn’t happening.
So, I stand by my comment that the winter warming is occuring at the same time we are seeing record winter ice formation measured by extent, and therefore warmer air temperatures have minimal effect on Arctic sea ice, and this is compelling GHG warming is not the cause of the Arctic sea ice loss.
What is?
Cloud reductions and embedded black carbon in older ice.
Philip Bradley says
GHG warming is not the cause of the Arctic sea ice loss.
What is?
Cloud reductions…
Come on Philip. Clouds are on the increase since it started cooling. And you do get a GH effect from more clouds, at certain places.
http://wattsupwiththat.com/2012/11/21/sea-ice-extent-linked-to-ocean-currents-hindcast-model-works/#comment-1154487
The situation really is as simple as I have put it earlier.
Count back 88 year and we are in 1924. What was the ice extent back then? Well, apparently much the same as it is now…..
http://wattsupwiththat.com/2012/11/21/sea-ice-extent-linked-to-ocean-currents-hindcast-model-works/#comment-1153736
Every 90 or 100 years (depending on the lag – earth also produces some energy) we are back again at the same point. So in two or three decades from now, all the “lost” arctic ice will be back.
Mark my words: There is really not much new under the sun.
One of my forefathers, a Dutch seaman in the 16th century by the name of Willem Barentsz was convinced from his “history lessons” that the north west passage did exist. He probably was right about that, because it would explain the movements of the Vikings at the beginning of the 2nd Millennium. Never mind, his timing was wrong. They died trying to find it, but they did name the sea after him.
So don’t worry. Be happy. The ice comes and goes, like the wind lies and blows, and nobody but the really clever people know why.
cant let a descendant of Barentsz have the final say . If loss of ice at high latitudes causes more snow at lower latitudes then it is welcome to the next ice-age and for cycles of this magnitude there is no history lesson…
be cause says
cant let a descendant of Barentsz have the final say . If loss of ice at high latitudes causes more snow at lower latitudes then it is welcome to the next ice-age and for cycles of this magnitude there is no history lesson…
henry says
there is (was) loss of ice at high latitudes (arctic) but not at the very low latitudes (antarctic),
This happens (in the arctic) every 90 or 100 years or so.
I don’t see an ice age coming, seeing that we are already near at the bottom of the cooling wave and nobody who is anybody in climate science even seemed to have noticed it…
Except me of course.
But I am always interested to hear what your results (of actual measurements) are?
HenryP says:
November 23, 2012 at 7:22 am
Come on Philip. Clouds are on the increase since it started cooling. And you do get a GH effect from more clouds, at certain places.
http://wattsupwiththat.com/2012/11/21/sea-ice-extent-linked-to-ocean-currents-hindcast-model-works/#comment-1154487
Henry, the problem is that current cloud measurements over the Arctic are problematic. The paper linked below says,
Over the Arctic as a whole, trends and interannual variations show little agreement with those from satellite data.
Above the Arctic circle in mid-summer gets more solar radiation than the tropics. Cloud cover is high, around 80% from memory. So, small changes in cloud cover will have substantial effects on surface insolation.
http://journals.ametsoc.org/doi/abs/10.1175/2010JCLI3544.1?journalCode=clim
Henry@Philip
Keep in mind that more cloud cover causes (more) cooling at lower latitudes but at higher latitudes where it would normally be much cooler, it causes a warming effect.
That is why we have now a bit of (arctic) ice melting. So, ironically, although the whole world is cooling there are a few places, at the receiving end of more clouds, getting a bit warmer.
t is clear from even a brief oerview of literature on the “bipolar seesaw” inter-hemispheric ocean heat “pendulum” exchange, associated with glacial-interglacial switching and phenomena such as the Heinrich and Dansgaard–Oeschger events, that significant changes and cycles in climate and ocean heat take place on century and millenial timescales.
http://193.146.160.29/gtb/sod/usu/$UBUG/repositorio/10280002_Seidov.pdf
http://www.fisica.edu.uy/~barreiro/papers/Blunier_etal_Science01.pdf
http://www.climate.unibe.ch/~stocker/papers/stocker03po-corr.pdf
http://www.leif.org/EOS/2010GL042793.pdf
ftp://psrd.hawaii.edu/coastal/Climate%20Articles/Climate%20seesaw%202009.pdf
In the context of this, knowing the ocean itself with its north-south heat exchanges can change climate at a range of timescales – why do warmists find natural climate variability so hard to understand or accept. Again there seems to be a disconnect between different scientific communities.
It is as though the astronomy of planetary dynamics never existed insofar as Arctic sea ice fluctuations have a singular cause that we can visually see and identify to a 100% certainty yet nobody affirms this observation.The polar coordinates act like a lighthouse beacon for the orbital behavior of a planet as it orbitally turns to the central Sun,this single rotation is coincident with the orbital period of a planet. so that Uranus turns at roughly 4 degrees per Earth year East to West while its daily rotation runs South to North –
http://www.daviddarling.info/images/Uranus_rings_changes.jpg
Believing that Arctic sea ice is caused by a fall in temperatures at the polar latitudes is a no brainer however what causes the temperatures to fall is a direct result of the orbital motion of the Earth and current researchers positively refuse to interpret those set of images above correctly in order to anchor studies of sea ice in planetary dynamics.
Gerald Kelleher says
…and current researchers positively refuse to interpret those set of images above correctly in order to anchor studies of sea ice in planetary dynamics.
Henry says
you could be right, actually, that the ice coverage can be linked to planetary dynamics, but I think you arrived at that conclusion from the wrong angle.
Surely, ice coverage depends mostly on how warm or how cold the sea currents are, together with the extent of cloud cover, which would have a warming effect, if there are more clouds, especially in winter.
These things are influenced by weather cycles.
Before they started with the carbon dioxide nonsense they did look in the direction of the planets, rightly or wrongly.See here.
http://www.cyclesresearchinstitute.org/cycles-astronomy/arnold_theory_order.pdf
To quote from the above paper:
A Weather Cycle as observed in the Nile Flood cycle, Max rain followed by Min rain, appears discernible with maximums at 1750, 1860, 1950 and minimums at 1670, 1800, 1900 and a minimum at 1990 predicted.
(The 1990 turned out to be 1995 when cooling started!)
Indeed one would expect more condensation (bigger flooding) at the end of a cooling period and minimum flooding at the end of a warm period. This is because when water vapor cools (more) it condensates (more) to form more clouds and water (i.e. more rain).
Now put my sine wave
http://blogs.24.com/henryp/2012/10/02/best-sine-wave-fit-for-the-drop-in-global-maximum-temperatures/
next to those dates?
1900- minimum flooding : end of warming
1950 – maximum flooding: end of cooling
1995 – minimum flooding: end of warming
Count back 88 years= 2012-88= 1924.
what was the ice back then? see here:
http://wattsupwiththat.com/2008/03/16/you-ask-i-provide-november-2nd-1922-arctic-ocean-getting-warm-seals-vanish-and-icebergs-melt/
Exactly as it now. So, in another two or three decades from now all the lost (arctic) ice will be back. Mark my words.
So far, I do not exclude a gravitational or electromagnetic swing/switch (pull from the planets?) that changes the UV coming into earth. In turn this seems to change the chemical reactions of certain chemicals reacting to the UV lying on top of the atmosphere. This change in concentration of chemicals lying on top of us, i.e. O3, HxOx and NxOx, in turn causes more back radiation (when there is more), hence we are now cooling whilst ozone & others are increasing.
Hope this helps a few people.
HenryP
Sometimes observations are so obvious that they are overlooked and especially in this case.The polar coordinates are carried around by the orbital behavior of the planet rather than the idea of ’tilt’ towards and away from the Sun implicit in older perspectives.It is exceptionally important for a dozen major reasons including why Arctic sea ice forms as the polar coordinates are swung away from solar radiation rather than inclination to solar radiation.
A planet has a climate spectrum with the Earth’s largely equatorial climate determined by its inclination unfortunately the community is susceptible to thinking in less than global terms when it comes to the planetary polar/equatorial spectrum even when it is possible to make planetary comparisons.
http://www.newscientist.com/data/images/ns/cms/dn12529/dn12529-1_800.jpg
This is not a case of throwing good information after a dysfunctional conclusion created by modelers,this is directed towards modifying why axial precession as it is presently understood is preventing a streamlined view of the physical considerations behind climate and why we have the seasons up to including Arctic sea ice fluctuations.Without assigning proper cause for the polar day/night cycle where polar latitudes are swung away from the Sun’s radiation for months on end,what is the point of discussing climate and any other input you care to introduce as to why sea ice forms ?.
There is a sense of dismay that climate studies may dissolve into attrition warfare using modeling rather than a clear breakthrough which would break the vicious cycle and take the urgency from climate studies,raise the intellectual standards and a return to a more stable narrative where ice sheet weather or lack of it influenced biological and geological evolution and even conditions where societies flourished and diminished due to short term variations.
Those set of images are not as easy to interpret as readers first imagine as the axial inclination remains fixed to the same point as a planet orbits the Sun just as the Earth’s daily rotational orientation remains fixed to Polaris.A person who walks/orbits a central object using a broom handle constantly pointing at an external object to substitute for daily rotation will quickly discover,as they walk/orbit the central object/Sun,that the line of their body substitutes for an ecliptic axis around which the polar coordinates turn to the central object/Sun just as the polar coordinates of Uranus act like a beacon for this orbital feature and why we see it at a great distance from the Earth –
http://dsc.discovery.com/news/briefs/20041108/gallery/uranus3_zoom.jpg
Give the concept a test drive as without the ecliptic axis it is impossible to ascertain why sea ice forms at the poles.
Gerald Kelleher says:
November 24, 2012 at 11:57 am
A bucket of cold seawater will cool you down faster than the orbital configuration of Uranus.
Henry@Gerald
Uranus is not doing anything for me either, yet. I think you must first try to understand the basics of what causes more or less energy to enter earth.. There is a whole lot of interesting things happening right up there on top of – and in – the atmosphere. Looking at maxima is the better parameter to do this.
Perhaps start here.
http://blogs.24.com/henryp/2011/08/11/the-greenhouse-effect-and-the-principle-of-re-radiation-11-aug-2011/
I am not saying we disagree. At this point, I just don’t know what exactly pulls the switch, throwing more FUV and/or EUV on top of us, causing an increase in ozone and other substances that radiate more energy away from us.
Phlogiston
It is hard to tell if that is a reaction or a response nevertheless the issue still stands that Arctic sea ice has a primary cause in terms of the polar day/night cycle and the annual temperature fluctuation as a consequence of the orbital behavior of the Earth just as daily temperature fluctuations have a primary cause in the daily rotation of the planet.
It is not just looking at an old topic in a new way,it alters how climate is defined,what causes latitudinal temperature fluctuations (seasons),why the natural noon cycle varies and many other topics.
It is true that it doesn’t attract the same audience who compete in a war of assertions but rather raises the standards by introducing planetary dynamical comparisons and more importantly,an ecliptic axis around which the polar coordinates are carried in a circle to the central Sun.It simply would not be on anybody’s radar as these observations get left behind in a rush to discuss long term ice patterns however most of the inherited views that began 500 years ago with Copernicus require a complete overhaul and especially now with the imaging power that makes planetary comparisons possible.
Modeling may come later but without the primary inputs,modeling without getting everything in order will always do more harm than good as this is a case in point.
HenryP
The current doom laden atmosphere has more to do with the lack of inspiration than the presence of desperation based on pseudoscientific modeling,in less frantic times it would have been possible to discuss the modification to the original conclusion of Copernicus using contemporary resources but researchers seem intent in squeezing climate investigations into a very narrow band of reasoning where the Earth is a greenhouse – It is not,the Earth is a planet and it would be nice if researchers started treating it like a moving planet and these alone are the primary cause of daily and annual temperature fluctuations
“,…the equator and the earth’s axis must be understood to have a variable inclination. For if they stayed at a constant angle, and were affected exclusively by the motion of the center, no inequality of days and nights would be observed. On the contrary,it day or the day of equal daylight and darkness, or summer or winter, or whatever the character of the season, it would remain identical and unchanged.” Copernicus
The issue is lost at high school level as not only are students not taught the proper reasons why seasons change and why axial inclination determines planetary climate within a equatorial/polar spectrum,current researchers don’t even bother to survey the original hypothesis which requires a decisive reworking for 21st century purposes.
As far as I am concerned,the sequence of images of Uranus announces a complete conceptual overhaul and annual Arctic sea ice fluctuations is as good a place as any to begin that process.Had the Earth an inclination similar to that of Uranus where the Arctic and Antarctic circles would expand over large latitudinal areas,the response of sea ice fluctuations would be much greater and perhaps that is where modeling would be more suitable than as a weapon for future predictions.
So, it’s all non-linear and complex? By definition, there is no such thing as a “forcing driver”, much less a linear one, in such a regime.
And please, leave off and lay off with the “reflecting solar radiation and shielding the planet from excessive warming” rhetoric. Protecting us from the evil, hot sun? Excessive (polar) warming? It’s excessive polar cold leaking out that drives dirty weather. It’s coming, and you won’t like it.