Greenland melting due equally to global warming, natural variations

May 07, 2014
Jakobshavn Glacier, Greenland. Warming temperatures over the last few decades have contributed to the acceleration of Greenland's large outlet glaciers. Credit: W. T. Pfeffer

The rapid melting of Greenland glaciers is captured in the documentary "Chasing Ice." The retreat of the ice edge from one year to the next sends more water into the sea. Now University of Washington atmospheric scientists have estimated that up to half of the recent warming in Greenland and surrounding areas may be due to climate variations that originate in the tropical Pacific and are not connected with the overall warming of the planet. Still, at least half the warming remains attributable to global warming caused by rising carbon dioxide emissions. The paper is published May 8 in Nature.

Greenland and parts of neighboring Canada have experienced some of the most extreme since 1979, at a rate of about 1 degree Celsius per decade, or twice the global average. "We need to understand why in the last 30 years is not uniform," said first author Qinghua Ding, a UW research scientist in atmospheric sciences. "Superimposed on this global average warming are some regional features that need to be explained."

The study used observations and advanced computer models to show that a warmer western tropical Pacific Ocean has caused atmospheric changes over the North Atlantic that have warmed the surface by about a half-degree per decade since 1979. "The pattern of the changes in the tropical Pacific that are responsible for remarkable atmospheric circulation changes and warming in Greenland and the Canadian Arctic are consistent with what we would call natural variability," said co-author David Battisti, a UW professor of atmospheric sciences.

Researchers say it's not surprising to find the imprint of natural variability in an area famous for its melting ice. In many of the fastest-warming areas on Earth, global warming and natural variations both contribute to create a "perfect storm" for warming, said co-author John "Mike" Wallace, a UW professor of atmospheric sciences.

The natural variations in the new study related to an unusually warm western tropical Pacific, near Papua New Guinea. Since the mid-1990s the water surface there has been about 0.3 degrees hotter than normal. Computer models show this affects the regional air pressure, setting off a stationary wave in the atmosphere that arcs in a great circle from the tropical Pacific toward Greenland before turning back over the Atlantic.

"Along this wave train there are warm spots where the air has been pushed down, and cold spots where the air has been pulled up," Wallace said. "And Greenland is in one of the warm spots."

In previous studies, Wallace and Battisti have documented the existence of decades-long climate variations in the Pacific Ocean that resemble the well-known shorter-range El Niño variations.

This particular location in the tropical Pacific may be a "sweet spot" for generating global atmospheric waves. A series of studies led by co-author Eric Steig, a UW professor of Earth and space sciences, working with Ding and Battisti, showed that waves starting in the same place but radiating southward are warming West Antarctica and melting the Pine Island Glacier.

Researchers can't say for how long the tropical Pacific will remain in this state. "Our work shows that about half of the warming signal in Greenland comes from the predictable part – forcing of climate by anthropogenic greenhouse gases – but about half comes from the unpredictable part," Steig said.

This makes shorter-term forecasts difficult, but helps scientists to make more accurate long-range projections.

"Nothing we have found challenges the idea that globally, glaciers are retreating," Battisti said. "We looked at this place because the warming there is really remarkable. Our findings help us to understand on a regional scale how much of what you see is human-induced by the buildup of CO2, and how much of it is natural variability."

The dramatic message of "Chasing Ice" remains true, authors say.

"There's nothing in this paper that negates the message in the movie," Wallace said. "Ice appears to be exquisitely sensitive to the buildup of greenhouse gases, more than we ever would have thought." Natural variations could either accelerate or decelerate the melting rate of Greenland's glaciers in coming decades, he said, but "in the long run, the human-induced component is likely to prevail."

Explore further: No 'permanent El Nino,' scientists say—and the tropics may get even hotter

More information: Paper: Tropical forcing of the recent rapid Arctic warming in northeastern Canada and Greenland, dx.doi.org/10.1038/nature13260

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enviro414
1.6 / 5 (11) May 08, 2014
Meteorology is a study of energy moving around the planet. This article is a study of that. It has very little to do with Global Warming.

The planet warmed from the Little Ice Age (LIA) until about 2001. Sunspot numbers do not correlate, but the time-integral of sunspot numbers (with a proxy factor) provides a credible measure of the warm up from the depths of the LIA with a noticeable slope increase in about 1940. The time-integral of sunspot numbers results from applying conservation of energy to the planet.

When an average for all ocean oscillations with period 64 years and amplitude ±0.18 K is added (oscillating above and below the warm-up trend), the result matches measured temperatures since before 1900 with R^2 > 0.9.

The combination shows that the planet stopped warming in 2001. http://agwunveile...pot.com/
runrig
4.3 / 5 (12) May 08, 2014

The planet warmed from the Little Ice Age (LIA) until about 2001. Sunspot numbers do not correlate, but the time-integral of sunspot numbers (with a proxy factor) provides a credible measure of the warm up from the depths of the LIA with a noticeable slope increase in about 1940. The time-integral of sunspot numbers results from applying conservation of energy to the planet.

When an average for all ocean oscillations with period 64 years and amplitude ±0.18 K is added (oscillating above and below the warm-up trend), the result matches measured temperatures since before 1900 with R^2 > 0.9.

The combination shows that the planet stopped warming in 2001. http://agwunveile...pot.com/

Mr enviro - my repeated criticism of this science free "article" you continually spam these pages with, stands.
The LIA was more a consequence of increased volcanic aerosols and a likely weaker Arctic Stratospheric vortex rather than any reduction of Solar energy emitted.
Pejico
May 08, 2014
This comment has been removed by a moderator.
enviro414
1.6 / 5 (12) May 08, 2014
Run – Apparently you are annoyed that climate change is adequately explained by natural phenomena alone. And apparently you are further annoyed that the explanation can be expressed in a simple equation. I wonder how much longer you will cling to your failed perception.
runrig
4.3 / 5 (12) May 09, 2014
Run – Apparently you are annoyed that climate change is adequately explained by natural phenomena alone. And appathe explanation can be expressed in a simple equation..........

No, not at all, anyone who knows the science is aware of the natural cycles running along with the the variations - ENSO and AMO (another warming influence over recent decades on Greenland).
Your statement that "the explanation can be expressed in a simple equation" tells it all really.
Do you really think that the answer to a warming world can be solved thus, on the back of a fag-packet, and that the whole world's experts missed it?
Only in the denialist world, and not a sane one.
The key thing to understand is the cyclic nature of the Sun's output ... that is NOT reflected in global temps.
http://www.newsci..._738.jpg
runrig
4.3 / 5 (12) May 09, 2014
I do strongly favor the natural explanation of global warming, but the natural variations considered in this article (i.e. the Rossby waves) can be just a consequence of global warming itself (with anthropogenic origin or without it). We should rather ask, what convinced the authors of this article to ignore this apparent fact?

The point is that there is NO natural explanation to a warming world.
Please name me one - along with correlation over the last ~150 years and causation physics.
Rossby wave train shifts to favoured/new positions is THE major way we we see changes in weather/climate - but it is merely a REDISTRIBUTION of energy internal to the Earth. What is out of balance is solar SW absorbed by the climate system, and LWIR emitted to space. This small imbalance is causing global energy (Sea & land) to rise. It's simple, well established and utterly unarguable physics.
enviro414
1.5 / 5 (8) May 10, 2014
Run - Well, if you won't even look…

For those who do look you will see a graph showing the excellent match of the calculated (using the simple equation) anomalies since 1610 with all average global temperature anomaly measurements from Hadley, NOAA, and GISS.

The prediction is merely that things will continue for at least a decade as they have for over a century.

A couple of 'experts' got part of the story. Their findings are graphed at http://conenssti.blogspot.com/ . The rest apparently were misled and have been barking up the wrong tree.

Three observations at http://www.middle...urn.html demonstrate that CO2 change has no significant effect on climate This was made public 6 years ago.

1) In the late Ordovician, the planet plunged into the Andean/Saharan ice age and later emerged from it while the CO2 level was about 10 times the present.
2) During the last glacial period, warming trends changed to cooling trends while the CO2 level was higher than it had been during the warming trend.
3) During the 20th century, average global temperature trends went down, up, down, up, flat (soon to be down) while the CO2 level went steadily, progressively up. Lack of correlation demonstrates lack of causation.

As long as you continue to harbor the false notion that the only effect that the sun can have is its slight (approx. 0.1%) variation in brightness (TSI) you will never understand how sunspots drive climate change.
runrig
4.1 / 5 (9) May 10, 2014
Enviro:
A quote from your linked site...
"For most of earth's history carbon dioxide level has been several times higher than the present8,9. The planet plunged in to the Andean-Saharan ice age 440 million years ago when the carbon dioxide level was over ten times higher than now.

The conclusion from all this is that carbon dioxide change does NOT cause significant climate change. Actions to control the amount of non-condensing greenhouse gases that are added to the atmosphere are based on the mistaken assumption that global warming was caused by human activity. These actions put freedom and prosperity at risk."

Are you, as this quote/site is saying, that the Earth 440m Years ago is an analogue of today's Earth?

If so then consider these elementary points...

Cont
runrig
4.1 / 5 (9) May 10, 2014
Cont

Are you aware of orbital eccentricity?
Are you aware of albedo?
Are you aware of volcanism (aerosol ejection)?
Are you aware the the Sun was weaker then?
Are you aware aware that the science of GHG's is unarguable?
Are you aware that that measured back-emitted IR from the atmosphere is routinely measured spectroscopically on at the Earth's surface and can directly attributed to the atmosphere's individual GHG constituents? and that it's measured as increasing?
Are you aware that satellite measures solar output to with fractions of a percent and there is no energy increase that can be attributed to the rise in global temps?
That satellites measure terrestrial IR to space and it lags SW absorbed?
Are you aware that there is NO correlation of CR's to temperature record?
Are you aware that the Sun behaves cyclically and that the temp record does not?
Are you aware that you are a Slayer denialist that even Watts and Spencer abhor?
Truly away with the fairies.
enviro414
1.7 / 5 (6) May 11, 2014
If you would look at the links you would know what I am aware of and what I address.
Are you aware of the things that you asked about that are ambiguous, or insignificant, or not relevant?
Eccentricity - doesn't change enough over centuries to matter so irrelevant.
Albedo - addressed. Change to it, driven by Sunspots, is a likely partial contributor to climate change as I show at http://lowaltitud...pot.com/
Volcanoes - addressed and shown on graph. Ambiguous because temperature might go either way following all volcanoes that have occurred since accurate average global temperature measurements have been made.
Weaker sun - Not relevant since the planet also RECOVERED from the ice age.
GHGs - Are you aware that by far the most significant GHG is water vapor? And that non-condensing GHGs have no significant effect on climate? Are you aware of thermalization?

cont
enviro414
1.6 / 5 (7) May 11, 2014
cont

Back emitted IR – This was addressed years ago including the effect of thermalization at http://climaterea...ture.pdf
Solar output – aka TSI. Addressed. Change to it is complimentary to observed average global temperature change but the effect is tiny.
IR & SW measurements – overruled by 95% correlation when considering only net of ocean oscillations and time-integral of the difference between yearly sunspot numbers and 1610-1940 average sunspot number.
CR – I don't know what you mean by CR but see previous for IR & SW.
Cycles – Solar cycles, of course. Temperature trends on earth have cycle with period approximately 64 years and double amplitude approximately 0.36 K. A glance at any of the ubiquitous temperature graphs would tell you that.
I'm aware that I discovered the two main climate drivers and a whole lot of other folks didn't.
runrig
4.1 / 5 (9) May 11, 2014
Enviro:
You seem to have had a problem in comprehension...I was referring to 440m yrs ago ?!

I will now address your spamming with reference to TODAY'S Earth....

If you would look at the links you would know what I am aware of and what I address.
Are you aware of the things that you asked about that are ambiguous, or insignificant, or not relevant?
Eccentricity - doesn't change enough over centuries to matter so irrelevant.


Correct - today the Earth is in a configuration whereby the SH receives 8% more solar insolation in it's summer than does the NH in its - therefore (as the vast mass of landmass is in the NH) the Earth is in fact slightly cooling vs it's long term (10's thou yrs) trends.

Albedo - addressed. Change to it, driven by Sunspots, is a likely partial contributor to climate change as I show at http://lowaltitud...pot.com/

Albedo is not driven by sunspots FFS. I referred to it re 440mya. It is a function of ice/snow cover and atmospheric aerosols.

cont
runrig
4.1 / 5 (9) May 11, 2014

Volcanoes - addressed and shown on graph. Ambiguous because temperature might go either way following all volcanoes that have occurred since accurate average global temperature measurements have been made.


A volcanic event (440mya) would have blanketed the Earth in aerosols hence an increased albedo. Today they cool Earth just the same, though on a small scale - find a graph that points out Pinatubo.

Weaker sun - Not relevant since the planet also RECOVERED from the ice age.


Was relevant on my post (440mya) - and there is no recovery from an ice age going on now as, I said, because the NH is receiving LESS insolation than the SH.

GHGs - Are you aware that by far the most significant GHG is water vapor? And that non-condensing GHGs have no significant effect on climate? Are you aware of thermalization?


Get away! A Nobel prize awaits my friend. Peer-reviewed paper please?
AND you do surprise me - WV is a GHG eh? - news to this meteorologist.

cont

Captain Stumpy
4 / 5 (8) May 11, 2014
pardon the interruption
Run - Well, if you won't even look…
@enviro
your link goes to a blog.
then you post other links that are to blogs.
BLOGS are NOT empirical data. blogs are not peer reviewed science. blogs are personal conjecture unless there is a study linked, and if there is a PEER REVIEWED STUDY linked, you should link THAT and forget about the blogs.
blogs are equally as valid as statements supporting the correlations between Fairy urine and ocean salinity (IOW - they are personal conjecture and NOT VALID arguments)

BLOGS are NOT an argument for logic or science, only BS, politics or philosophy, none of which are relevant to the article or science AFAICT

I dont know about Runrig, but I no longer read blog links. if there is valid studies, science or empirical data, use those links, otherwise the link/blog is no better than saying "Unicorn sneezes cause thunder and lightning is fairy urine"
runrig
4.2 / 5 (10) May 11, 2014
WV is confined by the hydrological cycle (~10 days in the atmos) to rigid limits on a planetary scale ( look - it just is). BUT it will increase with temperature - get it - the temp comes first and NOT the H2O.

Sorry, hand-waving aint good enough - GHG science is unarguable - get down the rabbit hole my friend.

Back emitted IR – This was addressed years ago including the effect of thermalization at http://climaterea...ture.pdf


Denialist Blogs don't count. GHG science is unarguable (go ask your fellow deniers but none slayers - Watts & Spencer) - as is the fact that the Earth is round. Get over it.

Solar output – aka TSI. Addressed. Change to it is complimentary to observed average global temperature change but the effect is tiny.


Correct. A gold star.
runrig
4.2 / 5 (10) May 11, 2014
IR & SW measurements – overruled by 95% correlation when considering only net of ocean oscillations and time-integral of the difference between yearly sunspot numbers and 1610-1940 average sunspot number.
CR – I don't know what you mean by CR but see previous for IR & SW.
Cycles – Solar cycles, of course. Temperature trends on earth have cycle with period approximately 64 years and double amplitude approximately 0.36 K. A glance at any of the ubiquitous temperature graphs would tell you that.
I'm aware that I discovered the two main climate drivers and a whole lot of other folks didn't.


Complete and utter rubbish/gobbledegook.

Sir, and Nobel laureate - I salute you.

Now, can I get back to the real world please?

Be a good boy and get back down the rabbit hole to talk to your fairies.
FFS
runrig
4.2 / 5 (10) May 11, 2014
I dont know about Runrig, but I no longer read blog links. if there is valid studies, science or empirical data, use those links, otherwise the link/blog is no better than saying "Unicorn sneezes cause thunder and lightning is fairy urine"


Capt:
I "look" at them occasionally for a laugh - or as in this case to trawl info to call out the "slayers" - as Enviro is.
I did know that Watts and Spencer consider the stuff Enviro is peddling as utter bollocks ( I posted on both of their Blogs).
So I just Googled for a quote/link.

Shootist
1.8 / 5 (10) May 11, 2014
Global Warming®

Still waiting to grow oranges in Alaska.
enviro414
1 / 5 (5) May 11, 2014
Run, Capt -

None are so blind as those who refuse to see.

Spencer still thinks that CO2 has a small effect. CO2 has no significant effect as I have shown with 5 independent events. Lindzen and a lot of others have come to the same realization that I have. I'm not sure where Watts is on this issue but he is speaking at the 9th International Conference on Climate Change in July at Las Vegas which I might attend.

Are you confident enough in your understanding that you will publicly declare, as I have, that average global temperatures are in a downtrend?

Are you confident enough in your understanding that you will publicly declare that average global temperatures will resume an uptrend? If so, how much longer will you wait for that to happen?

runrig
5 / 5 (6) May 11, 2014
Global Warming®

Still waiting to grow oranges in Alaska.


If oranges could grow in Alaska - the human race truly would be in trouble ... well dead in many parts of the planet.
runrig
5 / 5 (7) May 11, 2014
Run, Capt -

None are so blind as those who refuse to see.


Exactly my sentiments, and I'm not arguing for that that is unarguable with you any more.
Caliban
5 / 5 (4) May 11, 2014


None are so blind as those who refuse to see.


How right you are, enviro, and --in addition to being virtually the only factually correct thing you have uttered in this thread-- also the most deliciously ironic.

When is your Eye Dr.'s appointment?

Captain Stumpy
5 / 5 (6) May 11, 2014
None are so blind as those who refuse to see.
@enviro
very true
here is another quote
only a complete idiot would accept someone's word or anything else when it is directly proven wrong or contradicted with empirical data.
accept no one at face value. accept no word as truth. always check resources and investigate the situation for yourself, and verify with something that will stand up in court. You are not here to guess: you are here to prove something.
You can trust only what you can prove.

now get back to work
Truck Captain Stumpy talking to new investigators at an Arson with fatalities 1994

I dont care about who says what. Only what can be proven. Runrig has earned my respect for posting data that can be PROVEN, and linking to studies/empirical data.

blogs have all he same weight as fairy turds to me, except that they are not as good for growing tomatoes. (hyperbole)

IOW-if I aint empirical, or a peer reviewed study, it aint worth my time and its worthless as proof
enviro414
1 / 5 (6) May 12, 2014
Are you confident enough in your understanding that you will publicly declare that average global temperatures will resume an uptrend? (crickets)

If so, how much longer will you wait for that to happen? (crickets)

Nuf (un)said
ryggesogn2
1 / 5 (5) May 12, 2014
"The results of the present study indicate that most of the glaciers were in a steady state compared to the results of other studies carried out for the period prior to 2001. This period of monitoring almost corresponds to hiatus in global warming in the last decade. It may happen that an interval of one decade could be smaller than the response time of glaciers to be reflected in terms of any significant change with 23.5 m spatial resolution of data. This point requires further studies using high-resolution data for a longer interval of time."
http://www.thegwp...w-study/
Captain Stumpy
5 / 5 (6) May 12, 2014
Are you confident enough in your understanding that you will publicly declare that average global temperatures will resume an uptrend?
@enviro
are you really that stupid? first of all... as I have said since coming here: I believe in the empirical data. the science.
2nd- I am NOT a meteorologist. I AM CONFIDENT ENOUGH to state publicly (just like always) that I continue to observe and I will believe the Empirical data and my mindset changes when the data says it must
3rd-
how much longer will you wait for that to happen?
You are assuming that someone here is a medium? a psychic?
4th & final: punt or field goal unless you can know absolutely you can get over the line.

if you are looking for psychics, try http://spiritnow.com or maybe http://psychiccen...ome.aspx

only SCIENCE here, sparky
ryggesogn2
1 / 5 (5) May 12, 2014
Will this science be noted by phys.org?

"The results of the present study indicate that most of the glaciers were in a steady state compared to the results of other studies carried out for the period prior to 2001. This period of monitoring almost corresponds to hiatus in global warming in the last decade. It may happen that an interval of one decade could be smaller than the response time of glaciers to be reflected in terms of any significant change with 23.5 m spatial resolution of data. This point requires further studies using high-resolution data for a longer interval of time."
http://www.thegwp...w-study/
MikPetter
5 / 5 (5) May 12, 2014
Global warming hiatus??? Really?? I think people are confusing a slowing in the rate of increase and a decline in temperatures. In fact the earth is still warming.
"The year 2013 tied with 2007 as the sixth warmest since global records began in 1850. The global average surface temperature was 0.50°C ±0.10°C (0.90°F ±0.18°F) above the 1961–1990 average and 0.03°C (0.05°F) above the 2001–2010 average. The past year was also warmer than both 2011 and 2012, which, though marked by cooling La Niña conditions, were 0.43°C and 0.46°C above average, respectively."
WMO statement on the status of the global climate in 2013
World Meteorological Organization 2014