Long-term study reveals: The deep Greenland Sea is warming faster than the world ocean

Sep 25, 2013

Since 1993, oceanographers from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), have carried out regularly expeditions to the Greenland Sea on board the research ice breaker Polarstern to investigate the changes in this region. The programme has always included extensive temperature and salinity measurements. For the present study, the AWI scientists have combined these long term data set with historical observations dating back to the year 1950. The result of their analysis: In the last thirty years, the water temperature between 2000 metres depth and the sea floor has risen by 0.3 degrees centigrade.

'This sounds like a small number, but we need to see this in relation to the large mass of water that has been warmed' says the AWI scientist and lead author of the study, Dr. Raquel Somavilla Cabrillo. 'The amount of heat accumulated within the lowest 1.5 kilometres in the abyssal Greenland Sea would warm the atmosphere above Europe by 4 degrees centigrade. The Greenland Sea is just a small part of the global ocean. However, the observed increase of 0.3 degrees in the deep Greenland Sea is ten times higher than the in the on average. For this reason, this area and the remaining less studied polar oceans need to be taken into consideration'.

The cause of the warming is a change in the subtle interplay of two processes in the Greenland Sea: the cooling by deep of very cold surface waters in winter and the warming by the import of relatively warm from the interior Arctic Ocean. "Until the early 1980s, the central Greenland Sea has been mixed from the top to the bottom by winter cooling at the surface making waters dense enough to reach the " explains Somavilla. "This transfer of cold water from the top to the bottom has not occurred in the last 30 years. However, relatively warm water continues to flow from the deep Arctic Ocean into the Greenland Sea. Cooling from above and warming through inflow are no longer balanced, and thus the Greenland Sea is progressively becoming warmer and warmer."

These modified conditions provide AWI scientists with unique research opportunities: "We use these changes as a natural experiment. The warming allows us to calculate how much water flows from the deep central Arctic into the Greenland Sea" says Prof. Dr. Ursula Schauer, head of the Observational Oceanography Department at the Alfred Wegener Institute, about this project and adds: "We observe here a distinct restructuring of the Arctic Ocean. This is a very slow process, and its documentation requires long term observations."

To fully understand how the world's oceans react to climate change, scientists need to investigate the Arctic Ocean in more detail. 'Due to its large volume and its thermal inertia the deep ocean is a powerful heat buffer for climate warming. Especially, the polar oceans are scarcely studied. If we want to understand the role of the deep ocean in the climate system, we need to expand the measurements to remote regions like the Arctic," AWI-scientist Schauer says. For that, she has already planned further Polarstern expeditions. In 2015, Ursula Schauer and her group will go back to the Arctic.

Glossary: Why are the deep waters from the interior Arctic Ocean warm?

The mean temperature of the deep from the interior Arcic Ocean is -0.9 degrees centigrade. That is much warmer than the of the Greenland Sea, which cool down to -1.8 degrees in winter. However, where does the warmth of the deep Arctic waters come from? It is the result of a long chain reaction, happening in the shallow seas on the edge of the Arctic Ocean – right there, where in winter sea ice formation takes place. When the ice is formed the salt, which is present in the water, does not get enclosed. It leaves the ice instead and increases the salinity and density of the water layer below the ice. Due to their rising density these waters get heavier and start sinking. One can compare this sinking process of the water masses with a snowball falling down a freshly snow-covered slope. The longer the snowball rolls, the more snow get attached to its body. That means, while rolling down the Arctic shelf, the salty sinking water masses come across a layer of warm Atlantic water. They take part of the heat and salt in this Atlantic layer and transport it to deeper levels in the Arctic Ocean. At the bottom of the Arctic Ocean these sinking water masses form a body of warm deep that later on streams out of the Arctic Ocean into the Greenland Sea.

Explore further: Stronger winds explain puzzling growth of sea ice in Antarctica

More information: R. Somavilla, U. Schauer and G. Budéus: Increasing amount of Arctic Ocean deep waters in the Greenland Sea, Geophysical Research Letters, VOL. 40, 4361, DOI: 10.1002/grl.50775, 2013

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Water_Prophet
1.2 / 5 (19) Sep 25, 2013
This scripture is an amazing revelation. Not one readily denied.
Those that have eyes, let them see, those that have thermometer, let them read.
Water_Prophet
1 / 5 (20) Sep 25, 2013
Thou dost realize that "Dark Matter" is simply "cold Elemental Earths," poorly detectable by visual or satellite means?
Perhaps you mean "dark energy" that false prophecy of energy responsible for the Universe accelerating it's expansion?
Or perhaps you refer to the heating of the Earth by radioactive means, which is essentially constant thoughout the domain of man, well documented in scripture?
djr
4.1 / 5 (13) Sep 26, 2013
How surreal. The climate denial war wages for years. The same names spam this site ad nasuem (uba, anti, R2, Nik etc. etc.) Evidence starts to amass that - no the warming has not ceased - and the airwaves go silent. Now all that is left are the total crazies - the water prophets, and the cold fusion conspiracy theorists - howling at the moon. It makes you feel like you are 'the man' in the movie 'The Road'. Wandering alone in a post apocalyptic nightmare.
Howhot
4 / 5 (12) Sep 28, 2013
How surreal. The climate denial war wages for years. The same names spam this site ad nasuem (uba, anti, R2, Nik etc. etc.) Evidence starts to amass that - no the warming has not ceased - and the airwaves go silent. Now all that is left are the total crazies - the water prophets, and the cold fusion conspiracy theorists - howling at the moon. It makes you feel like you are 'the man' in the movie 'The Road'. Wandering alone in a post apocalyptic nightmare.


uba, anti, R2, Nik etc. etc trolling. They will be the first eaten in the coming zombie apocalypse
Water_Prophet
1.2 / 5 (19) Sep 28, 2013
Ah, djr, "what's in a name?"

Why is it that there are so many false prophets on this site. Not "crazies" like this earnest and humble prophet, but those who post false scripture to confound?
Kiwini
1.4 / 5 (19) Sep 28, 2013
Ah, djr, "what's in a name?"

Why is it that there are so many false prophets on this site. Not "crazies" like this earnest and humble prophet, but those who post false scripture to confound?


Et tu, Brute?...
Caliban
4.2 / 5 (5) Sep 28, 2013
Ah, djr, "what's in a name?"

Why is it that there are so many false prophets on this site. Not "crazies" like this earnest and humble prophet, but those who post false scripture to confound?


Speak plainly, sir, and perhaps someone will repond to the content of your posts.

The Koans of the Sages remain safe.
Water_Prophet
1.2 / 5 (17) Sep 28, 2013
Ah, djr, "what's in a name?"

Why is it that there are so many false prophets on this site. Not "crazies" like this earnest and humble prophet, but those who post false scripture to confound?


Speak plainly, sir, and perhaps someone will repond to the content of your posts.

The Koans of the Sages remain safe.

"Sir"?
markx
1.3 / 5 (14) Sep 30, 2013
Subtleties of wording:

AR4 published in 2007 stated that the planet was warming at a rate of 0.2C every decade.
AR4 said there was "90% confidence" that AG emissions are responsible for "most" of the recent warming.

AR5: the warming since 1951 has been 0.12C per decade – a rate below even the lowest computer prediction.
AR5: there is a "95% confidence" that AG emissions are responsible for "more than half" of recent warming.

VendicarE
3.7 / 5 (10) Sep 30, 2013
"AR4 published in 2007 stated that the planet was warming at a rate of 0.2C every decade." - MarkxTard - Sockpuppet since September 24, 2013

Which is a present tense measure.

"AR5: the warming since 1951 has been 0.12C per decade" - MarkxTard

Which is an average taken over many decades and not a current trend.

Poor MarkieTard. You seem to have the reading comprehension of a grade 6 student.

You must be American.

Neinsense99
2.2 / 5 (17) Oct 01, 2013
How surreal. The climate denial war wages for years. The same names spam this site ad nasuem (uba, anti, R2, Nik etc. etc.) Evidence starts to amass that - no the warming has not ceased - and the airwaves go silent. Now all that is left are the total crazies - the water prophets, and the cold fusion conspiracy theorists - howling at the moon. It makes you feel like you are 'the man' in the movie 'The Road'. Wandering alone in a post apocalyptic nightmare.


uba, anti, R2, Nik etc. etc trolling. They will be the first eaten in the coming zombie apocalypse

Bring plenty of herbs and spices. Even the undead have standards.
Sinister1811
2.5 / 5 (18) Oct 01, 2013
How surreal. The climate denial war wages for years. The same names spam this site ad nasuem (uba, anti, R2, Nik etc. etc.) Evidence starts to amass that - no the warming has not ceased - and the airwaves go silent. Now all that is left are the total crazies - the water prophets, and the cold fusion conspiracy theorists - howling at the moon. It makes you feel like you are 'the man' in the movie 'The Road'. Wandering alone in a post apocalyptic nightmare.


uba, anti, R2, Nik etc. etc trolling. They will be the first eaten in the coming zombie apocalypse

Bring plenty of herbs and spices. Even the undead have standards.


Thing is, the herbs and spices aren't enough to mask that smell. Let's hope the zombies don't mind. ;)
ryggesogn2
1 / 5 (15) Oct 01, 2013
What about the rest of the world's oceans below 2000 meters?
"The mean temperature of the deep water masses from the interior Arcic Ocean is -0.9 degrees centigrade. That is much warmer than the surface waters of the Greenland Sea, which cool down to -1.8 degrees in winter."

Normally warmer water rises. But then when salt is added, densities change. Deep ocean water has more salt and is more dense, or it would not be on the bottom.
ryggesogn2
1 / 5 (15) Oct 01, 2013
"To fully understand how the world's oceans react to climate change, scientists need to investigate the Arctic Ocean in more detail. 'Due to its large volume and its thermal inertia the deep ocean is a powerful heat buffer for climate warming. Especially, the polar oceans are scarcely studied."

What about the rest of the deep ocean below 2000 meters?
Water_Prophet
1.3 / 5 (15) Oct 05, 2013
@ryggeson2
Your comments are good, but I fear you must investigate the implications of warming the seas and oceans in general.
That it is happening is startling, even to this prophet. Like knocking a mountain over with a feather.
ryggesogn2
1 / 5 (14) Oct 05, 2013
That it is happening is startling,

The ocean is very big and not homgenous.
The Gulf of California gets very warm from AUG through NOV every year. Does this startle you?
Water_Prophet
1.3 / 5 (15) Oct 05, 2013
Now your are a false prophet.
Spring, Summer, Fall and Winter changes do not startle me, of course.
ryggesogn2
1 / 5 (13) Oct 05, 2013
"Thus one of the most formidable scientific challenges facing society
is the need to develop a better understanding of how the climate system operates and to predict,
to the extent possible, the changes in climate and the environment that society must cope with in
the future. Because of the great complexity of the climate system and the many different
disciplines that are required to deal with it, this is arguably the most difficult scientific task that
has been undertaken. Because the natural response times of the ocean lie in the range of decades
to centuries, understanding and predicting its behavior is essential for planning for the next few
centuries."
"three problems which limit our ability to
predict the ocean's behavior. They are 1) our poor understanding of small-scale mixing
processes, 2) our inability to characterize the stability characteristics of the ocean circulation, and
3) the presence of chaotic elements in the ocean's behavior. These problems are not independent."
ryggesogn2
1 / 5 (13) Oct 05, 2013
(cont)
"One key
question that needs to be addressed is the question of whether the major sources of error growth
are fluctuations in the ocean or in the atmosphere, and if the latter, which surface flux
fluctuations lead to the most rapid error growth. From the point of view of climate the key
question that needs to be addressed is, to what extent does this error growth dominate over
changes in forcing in controlling climate change?"
http://web.mit.ed...t106.pdf
Water_Prophet
1.3 / 5 (15) Oct 05, 2013
And yet you're continuing to be a false prophet.
Why are you attempting to mix oil and water? The deep waters are the topic, not the surface and it's currents, yet you bring these good scripture out to validate your false prophesy.
You must seek redemption.
Howhot
3.9 / 5 (8) Oct 07, 2013
"... one of the most formidable scientific challenges facing society is the need to develop a better understanding of how the climate system operates and to predict, to the extent possible, the changes in climate and the environment that society must cope with in the future."

Which is what happens everyday and everyday it looks worst than the day before. We have to stop global warming or earth dies.
ubavontuba
1.2 / 5 (17) Oct 07, 2013
"... one of the most formidable scientific challenges facing society is the need to develop a better understanding of how the climate system operates and to predict, to the extent possible, the changes in climate and the environment that society must cope with in the future."

Which is what happens everyday and everyday it looks worst than the day before. We have to stop global warming or earth dies.
Ridiculous fear-mongering.. A warmer Earth is a greener Earth.
Water_Prophet
1.5 / 5 (16) Oct 08, 2013
@ubavontuba:
An interesting prophesy. Warmer does mean more of the blessed element both in cycle and in ubiquity.
Pray, say more...!
ubavontuba
1.3 / 5 (15) Oct 08, 2013
@ubavontuba:
An interesting prophesy. Warmer does mean more of the blessed element both in cycle and in ubiquity.
Pray, say more...!
What? You mean the diviner of all things water doesn't know this? LOL. Maybe that's because it's not exactly a direct result of increased precipitation?

Here's an article on it:

http://news.agu.o...greener/

And here's a map of a once warmer (and greener) globe. Greenland was really green! ...and look at Antarctica!

http://jan.ucc.na...moll.jpg

May the blessed water always be with you...

VendicarE
3.9 / 5 (7) Oct 08, 2013
"A warmer Earth is a greener Earth." - UbVonTard

Ya, just look at Venus.
ubavontuba
1.3 / 5 (16) Oct 08, 2013
"A warmer Earth is a greener Earth." - Uba

"Ya, just look at Venus." - Vendi-chatterbot
Venus isn't Earth ...not even close.

Did you even know a Venusian day lasts longer than a Venusian year?

ryggesogn2
1.5 / 5 (16) Oct 08, 2013
Being closer to the sun, Venus receives more solar radiation than earth. Almost twice as much, 2611 W/m2 compared to 1366 W/m2 for earth.
Water_Prophet
1.3 / 5 (16) Oct 08, 2013
@ubavontuba
So you disparage me with vulgar scripture, even as I praise your insight?
How uninspired.
Please, let those of pure heart @phys.org forgive my folly.
Neinsense99
2.2 / 5 (13) Oct 08, 2013
"... one of the most formidable scientific challenges facing society is the need to develop a better understanding of how the climate system operates and to predict, to the extent possible, the changes in climate and the environment that society must cope with in the future."

Which is what happens everyday and everyday it looks worst than the day before. We have to stop global warming or earth dies.

Rather, Earth as we know it and what we like to think passes for advanced civilization. Earth itself will continue.
Howhot
4.2 / 5 (5) Oct 09, 2013
"We have to stop global warming or earth dies." So very true.

R2 says; "Being closer to the sun, Venus receives more solar radiation than earth. Almost twice as much, 2611 W/m2 compared to 1366 W/m2 for earth."

I guess the venuisians don't need to build nuclear reactors or burn coal/gas/oil/shale either. They must do the obvious an use solar energy for their energy needs. Its funny how earth can have 1366 W/m2 (averaged over the globe BTW) of solar energy, day after day after day for billions of years.
ubavontuba
1 / 5 (12) Oct 09, 2013
@ubavontuba
So you disparage me with vulgar scripture, even as I praise your insight?
How uninspired.
Please, let those of pure heart @phys.org forgive my folly.
Me, disparage the Water_Prophet? Nay! I but provideth the Water_Prophet a trickle of insight.

VendicarE
4 / 5 (4) Oct 10, 2013
Being closer to the sun, Venus receives more solar radiation than earth. Almost twice as much," - RyggTard

And at the orbit of Mercury, the brightness of the sun is ten times that reaching the earth, but Mercury's average temperature is only 170'C.

Venus however, has an average surface temperature of 460'C.

How is Venus hotter when it receives less sunlight, TardieBoy?

VendicarE
4 / 5 (4) Oct 10, 2013
"Venus isn't Earth" - UbVonTard

How is it that Venus has a temperature that is 460'C when the earth's average temperature is only 15'C, and Mercury's temperature is only 170'c and yet sunlight at the orbit of Mercury is 10 times more powerful than it is at the earth?

Poor UbvonTard. Like RyggTard, he is scientifically illiterate.

Sinister1811
2.2 / 5 (13) Oct 10, 2013
Did you even know a Venusian day lasts longer than a Venusian year?


What does that have to do with anything? If that was the only factor, it'd be baked on one side and cold on the other.

Being closer to the sun, Venus receives more solar radiation than earth. Almost twice as much, 2611 W/m2 compared to 1366 W/m2 for earth.


And yet, Mercury is much closer to the sun than Venus. And Venus is hotter than Mercury by about 200 degrees. That, and Venus shows no signs of temperature changes either.
ubavontuba
1 / 5 (7) Oct 20, 2013
Did you even know a Venusian day lasts longer than a Venusian year?


What does that have to do with anything? If that was the only factor, it'd be baked on one side and cold on the other.
If Earth had such a slow rotation, do you really think Earth might appear anything like it does today?