Greenland 2012

[TerryM]

Nasa gets into the act re. the Big Melt in Greenland.

http://science.nasa....4jul_greenland/

The takeaway quote:

"Such pronounced melting at Summit and across the ice sheet has not occurred since 1889."

makes some of the earlier speculations about 1930's temperatures moot.

Rain yesterday around Flade Isblank may have added to the melt, but we'll have to wait for a break in the clouds to assess the results. The east coast, possibly because of a slowing in Fram outflow has been losing fast ice at an accelerated pace. The NEW Polynia has expanded and 79 might get interesting as the season progresses, even though the extreme heat seems to have eased.

I think the fast ice in Kane Basin shielding Humboldt Glacier has broken up, although it's hard to see through the clouds. Peterman Fjord is clearly visible with MODIS & the new ice island PII2012 is making good time heading toward Hall Basin.

My pet area this year, King Christian IV Glacier, is obscured. I don't really expect anything spectacular to happen there for decades, but the melt ponds and darkened surface at such a high elevation make it worth watching. The horn of Humboldt is another feature I keep track of, not so much because I expect it to go, but because if it did it would be a huge event.

I suspect that this year is going to top everything recorded for Greenland ice loss, but a lot will depend on how long the melt season lasts. 2011 had a spectacular but short melt season with Independence Fjord open for the first time since 2002. I'm sure it's going to open again this year with lots of the MY fast ice near Nord going. - we'll see.

Terry

[LocoAko]

Just heard about this on ABC News. Holy crap.

http://www.nasa.gov/...nland-melt.html

http://www.huffingtonpost.com/2012/07/24/greenland-ice-melt-nasa_n_1698129.html

Extent of surface melt over Greenland’s ice sheet on July 8 (left) and July 12 (right). Measurements from three satellites showed that on July 8, about 40 percent of the ice sheet had undergone thawing at or near the surface. In just a few days, the melting had dramatically accelerated and an estimated 97 percent of the ice sheet surface had thawed by July 12. In the image, the areas classified as “probable melt” (light pink) correspond to those sites where at least one satellite detected surface melting. The areas classified as “melt” (dark pink) correspond to sites where two or three satellites detected surface melting. The satellites are measuring different physical properties at different scales and are passing over Greenland at different times. As a whole, they provide a picture of an extreme melt event about which scientists are very confident. Credit: Nicolo E. DiGirolamo, SSAI/NASA GSFC, and Jesse Allen, NASA Earth Observatory

For several days this month, Greenland's surface ice cover melted over a larger area than at any time in more than 30 years of satellite observations. Nearly the entire ice cover of Greenland, from its thin, low-lying coastal edges to its two-mile-thick center, experienced some degree of melting at its surface, according to measurements from three independent satellites analyzed by NASA and university scientists.

On average in the summer, about half of the surface of Greenland's ice sheet naturally melts. At high elevations, most of that melt water quickly refreezes in place. Near the coast, some of the melt water is retained by the ice sheet and the rest is lost to the ocean. But this year the extent of ice melting at or near the surface jumped dramatically. According to satellite data, an estimated 97 percent of the ice sheet surface thawed at some point in mid-July.

Researchers have not yet determined whether this extensive melt event will affect the overall volume of ice loss this summer and contribute to sea level rise.

"The Greenland ice sheet is a vast area with a varied history of change. This event, combined with other natural but uncommon phenomena, such as the large calving event last week on Petermann Glacier, are part of a complex story," said Tom Wagner, NASA's cryosphere program manager in Washington. "Satellite observations are helping us understand how events like these may relate to one another as well as to the broader climate system."

Son Nghiem of NASA's Jet Propulsion Laboratory in Pasadena, Calif., was analyzing radar data from the Indian Space Research Organisation's (ISRO) Oceansat-2 satellite last week when he noticed that most of Greenland appeared to have undergone surface melting on July 12. Nghiem said, "This was so extraordinary that at first I questioned the result: was this real or was it due to a data error?"

Nghiem consulted with Dorothy Hall at NASA's Goddard Space Flight Center in Greenbelt, Md. Hall studies the surface temperature of Greenland using the Moderate-resolution Imaging Spectroradiometer (MODIS) on NASA's Terra and Aqua satellites. She confirmed that MODIS showed unusually high temperatures and that melt was extensive over the ice sheet surface.

Thomas Mote, a climatologist at the University of Georgia, Athens, Ga; and Marco Tedesco of City University of New York also confirmed the melt seen by Oceansat-2 and MODIS with passive-microwave satellite data from the Special Sensor Microwave Imager/Sounder on a U.S. Air Force meteorological satellite.

The melting spread quickly. Melt maps derived from the three satellites showed that on July 8, about 40 percent of the ice sheet's surface had melted. By July 12, 97 percent had melted.

This extreme melt event coincided with an unusually strong ridge of warm air, or a heat dome, over Greenland. The ridge was one of a series that has dominated Greenland's weather since the end of May. "Each successive ridge has been stronger than the previous one," said Mote. This latest heat dome started to move over Greenland on July 8, and then parked itself over the ice sheet about three days later. By July 16, it had begun to dissipate.

Even the area around Summit Station in central Greenland, which at 2 miles above sea level is near the highest point of the ice sheet, showed signs of melting. Such pronounced melting at Summit and across the ice sheet has not occurred since 1889, according to ice cores analyzed by Kaitlin Keegan at Dartmouth College in Hanover, N.H. A National Oceanic and Atmospheric Administration weather station at Summit confirmed air temperatures hovered above or within a degree of freezing for several hours July 11-12.

"

Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time," says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data. "But if we continue to observe melting events like this in upcoming years, it will be worris

ome."

Nghiem's finding while analyzing Oceansat-2 data was the kind of benefit that NASA and ISRO had hoped to stimulate when they signed an agreement in March 2012 to cooperate on Oceansat-2 by sharing data.

Maria-José Viñas

NASA's Earth Science News Team

Goddard Space Flight Center, Greenbelt, Md.

[TerryM]

A nice close-up of PII2012

http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=78648

suitable for framing.

Terry

[SVT450R]

Nasa gets into the act re. the Big Melt in Greenland.

http://science.nasa....4jul_greenland/

The takeaway quote:

"Such pronounced melting at Summit and across the ice sheet has not occurred since 1889."

makes some of the earlier speculations about 1930's temperatures moot.

Rain yesterday around Flade Isblank may have added to the melt, but we'll have to wait for a break in the clouds to assess the results. The east coast, possibly because of a slowing in Fram outflow has been losing fast ice at an accelerated pace. The NEW Polynia has expanded and 79 might get interesting as the season progresses, even though the extreme heat seems to have eased.

I think the fast ice in Kane Basin shielding Humboldt Glacier has broken up, although it's hard to see through the clouds. Peterman Fjord is clearly visible with MODIS & the new ice island PII2012 is making good time heading toward Hall Basin.

My pet area this year, King Christian IV Glacier, is obscured. I don't really expect anything spectacular to happen there for decades, but the melt ponds and darkened surface at such a high elevation make it worth watching. The horn of Humboldt is another feature I keep track of, not so much because I expect it to go, but because if it did it would be a huge event.

I suspect that this year is going to top everything recorded for Greenland ice loss, but a lot will depend on how long the melt season lasts. 2011 had a spectacular but short melt season with Independence Fjord open for the first time since 2002. I'm sure it's going to open again this year with lots of the MY fast ice near Nord going. - we'll see.

Terry

Interesting that you kept this little tidbit out of your quote.

"Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time," says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data. "But if we continue to observe melting events like this in upcoming years, it will be worrisome."

[TerryM]

Interesting that you kept this little tidbit out of your quote.

"Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time," says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data. "But if we continue to observe melting events like this in upcoming years, it will be worrisome."

I didn't quote it because I'm skeptical of the statement. A few of us are wondering how they came up with the 150 year figure since the bore hole only goes down to 1750, and there was only one previous event. A grad student doing her doctoral thesis on the core happened to be on site when the event occurred, and now we're trying to get a clearer picture of how they came up with that figure.

It's certainly possible that there are other cores nearby that could have the answer. At present questions have been raised by more than a small number of us & some have the credentials to merit fairly rapid responses.

I assume you've read Box's and Muenchow's takes on the event where either the 150 year figure is not given, or it is questioned.

I don't know how a trend can be seen when there has been only one previously recorded occurrence of an event. but we should have some answers in a relatively short time and I will post them.

Terry

[SVT450R]

The way i look at it is that your skeptical of what that number represents which is that Greenland has had warm/melting in the past.

[The_Global_Warmer]

Friv

Something you may have missed from Dr Box at meltfactor

Thanks to Chris Biscan via Neven’s

Arctic Sea Ice Blog for identifying an accessible source of Advanced Scatterometer (ASCAT) data.

another quote

In my recently accepted albedo paper (

Box et al. 2012, ACCEPTED VERSION), see abstract, the statement: “it is reasonable to expect 100% melt area over the ice sheet within another similar decade of warming.” may be coming true already.

http://www.meltfactor.org/blog/?p=556

Terry

Thanks for the head's up Terry. I will tweet Dr. Box a thanks for the shout out. He is a good guy and and doing great research for us all.

[TerryM]

The way i look at it is that your skeptical of what that number represents which is that Greenland has had warm/melting in the past.

II don't think so - otherwise I wouldn't have posted the article. Greenland obviously warmed in 1889. It obviously didn't warm to this extent in the 30's. I don't understand how someone could extrapolate a pattern if there really was only one other instance of the event and I try not to let ideology trump facts.

Terry

[Msalgado]

II don't think so - otherwise I wouldn't have posted the article. Greenland obviously warmed in 1889. It obviously didn't warm to this extent in the 30's. I don't understand how someone could extrapolate a pattern if there really was only one other instance of the event and I try not to let ideology trump facts.

Terry

I would imagine the data for the cycles comes from ice cores and is more extensive than one instance.

[TerryM]

I would imagine the data for the cycles comes from ice cores and is more extensive than one instance.

I hope so - at the moment it seems as though the core they were examining only goes back to 1750, and it had one instance in 1889 that compared to the recent one.

Obviously cores from sites at lower altitudes wouldn't be comparable and that may be the source of the confusion.

We should have some answers before the week is over.

Terry

[The_Global_Warmer]

The way i look at it is that your skeptical of what that number represents which is that Greenland has had warm/melting in the past.

The information presented is from one ice core, from one year. That means one year saw melting a the summit which could of been a product of an extreme pattern and likely was. You guys use the AMO as a huge factor in arctic sea ice but that would also mean it's a big factor in Greenland glacial melt. And considering 1889 did have a high spike at the time, it's no where close to today.

[donsutherland1]

From NBC News.com:

Three satellites found that 97 percent of Greenland -- the land mass second only to Antarctica for its volume of ice -- underwent a thaw never before seen in 33 years of satellite tracking, NASA reported Tuesday.

Satellite experts at first didn't trust their readings, especially since they showed an incredible acceleration. Over four days, Greenland's ice sheet -- which covers 683,000 square miles -- went from 40 percent in thaw to nearly entirely in thaw.

http://worldnews.nbc...lites-show?lite

This data does not mean that Greenland's ice sheet will disappear anytime soon. What it does mean is that the current Arctic warmth, which is probably unprecedented during the instrument period, is impacting virtually all of Greenland. It is not a locally-confined situation.

[SVT450R]

II don't think so - otherwise I wouldn't have posted the article. Greenland obviously warmed in 1889. It obviously didn't warm to this extent in the 30's. I don't understand how someone could extrapolate a pattern if there really was only one other instance of the event and I try not to let ideology trump facts.

Terry

The way it was worded says that it's happened more then once maybe they also used other data from other cores to come to that conclusion. It's fine if you want to keep brushing off the 30s but the data shows that it was about equally warm besides the recent high anomaly years.

[SVT450R]

The information presented is from one ice core, from one year. That means one year saw melting a the summit which could of been a product of an extreme pattern and likely was. You guys use the AMO as a huge factor in arctic sea ice but that would also mean it's a big factor in Greenland glacial melt. And considering 1889 did have a high spike at the time, it's no where close to today.

Yea just like we have been observing blocky patterns over Greenland that have been contributing to the melt. I also do believe the AMO is a big factor in Greenland melt.

[ben4vols]

The information presented is from one ice core, from one year. That means one year saw melting a the summit which could of been a product of an extreme pattern and likely was. You guys use the AMO as a huge factor in arctic sea ice but that would also mean it's a big factor in Greenland glacial melt. And considering 1889 did have a high spike at the time, it's no where close to today.

Come on Friv, why the need to post doctored graphs? Why not just post the regular AMO instead of doctoring a new graph? Why are you posting a graph of Arctic temperatures that have been heavily manipulated? Why don't you post the actual arctic temperature vs the revised Arctic temperature and let people make up their own minds? It's easy to show warming when one doctors the data to show warming. 20 out of 23 stations, used to make up the Arctic as a whole were all manipulated in the same fashion.

[Isotherm]

An overlay of the temp anomalies in 8 Greenland stations vs the Atlantic Multidecadal Oscillation (AMO) reveal a strong correlation between the two.

Below are the 8 various stations and their corresponding temp anomalies throughout the past century:

An average of those 8 stations' temp anomalies:

And finally the AMO:

One can see the very close relationship b/t the swings of the AMO and the temp anomalies of those Greenland stations. It's not surprising as Alaska's temps follow the PDO fairly closely, thus is makes sense that Greenland is highly dependent upon temperature variations of the Atlantic Ocean. Until we see a cooling of the Atlantic, which is not likely to occur for another 10 years at least, Arctic sea ice will probably be below/well below normal by our measuring standards. If the 1930s were included in our sea ice record, I would bet that we'd be quite comparable to those years. Greenland temps will be above normal during warm periods of the AMO, and generally below normal during cool periods.

[PhillipS]

An overlay of the temp anomalies in 8 Greenland stations vs the Atlantic Multidecadal Oscillation (AMO) reveal a strong correlation between the two.

Below are the 8 various stations and their corresponding temp anomalies throughout the past century:

An average of those 8 stations' temp anomalies:

And finally the AMO:

One can see the very close relationship b/t the swings of the AMO and the temp anomalies of those Greenland stations. It's not surprising as Alaska's temps follow the PDO fairly closely, thus is makes sense that Greenland is highly dependent upon temperature variations of the Atlantic Ocean. Until we see a cooling of the Atlantic, which is not likely to occur for another 10 years at least, Arctic sea ice will probably be below/well below normal by our measuring standards. If the 1930s were included in our sea ice record, I would bet that we'd be quite comparable to those years. Greenland temps will be above normal during warm periods of the AMO, and generally below normal during cool periods.

You used the detrended AMO chart. I believe that if you use the unadjusted AMO chart the correlation will appear stronger - particularly eartly in the record.

But, as we all know, correlation does not imply causation. The same process that drives the AMO may also be influencing Greenland melting.

If you're saying that the Atlantic will have to cool to historic levels before sea ice will recover and Greenland melting will abate - I agree - but as long as we are adding to AGW by annually dumping gigatons of CO2 into the atmosphere I don't see any hope of that happening.

[ben4vols]

If you're saying that the Atlantic will have to cool to historic levels before sea ice will recover and Greenland melting will abate - I agree - but as long as we are adding to AGW by annually dumping gigatons of CO2 into the atmosphere I don't see any hope of that happening.

It wouldn't take historic Atlantic cooling to abate the Greenland melt and start adding back sea ice. It would take appreciable cooling for a long period of time though. I also don't understand your argument about AGW and you seeing little chance of Atlantic cooling. The Pacific has cooled over the last 17 years while the Atlantic has warmed. It has very little to do with AGW and the North Atlantic will cool just as the North Pacific has.

[Conclue]

There seems to be a stagnet high pressure system over Greenland; however a quick plot of anomalous air temperature for 7/18 - 7/22 from ESLR doesn't quite show anything significant in the past 4 days at either 850hPa or 1000hPa. I was just interested to see if there was any synoptic reasoning for the accelerated apparent melt. Interesting. Now my wheels are turning.

I was quite suprised to see this on yahoo.com last night. My jaw dropped. I also don't like these "happens every 150 years" references either. In my personal opinion how can we say for certain that it was this excessive a 150 years ago? Are the data samples of ice cores widespread enough to say with certainity that this is indeed a 150 year event? I wouldn't put my money on just one ice core that shows this possibility.

Edit: (coffee cup is still half full, didn't see page 2) if this data that truley suggests this happened a 150 years ago is from just one ice core than I have a hard time accepting it as a analog; someone mentioned above what I was allready thinking that a specific synoptic pattern could be the culprit. I did a paper for college a couple years back on the 2007 arctic sea ice loss and I found that much of the melt was more strongly influenced by the particular synoptic weather pattern that specific year. That was my reasoning for checking out the synoptic pattern first in trying to think about what could be causing this sudden change?

LOL Are they sure the data isn't off? LOL I'm kind of stumped now.

[TerryM]

Actually an ice core from NEEM - south east of Thule & at a low elevation shows a melt in 1935 and 1879

http://adsabs.harvard.edu/abs/2011AGUFM.C33C0661K

This indicates a couple of things. First that there was a warm period in 1935 at this location, but also that the 1889 melt was not felt throughout Greenland, even though it was recorded at the summit. Or that the dating of one or the other is off by a decade.

The core from gisp2, on the other hand, which is from extreme elevation shows 4 events in the last 1,000 years. One possibly the 1889 event and the others in the early part of the Viking age with a gap between approx 1250 and 1900.

Adding our present melt we've had 5 in 1,000 years and 7 in the last 2,000 years. How that can be interpreted as an event that occurs every 150 years is beyond me.

http://www.gisp2.sr.unh.edu/DATA/alley1.html

Still hopeful we'll have answers before the week is out.

Terry

BTW Greenland temperatures recorded at seaside locals would be expected to be strongly influenced by ocean temps.

[PhillipS]

It wouldn't take historic Atlantic cooling to abate the Greenland melt and start adding back sea ice. It would take appreciable cooling for a long period of time though. I also don't understand your argument about AGW and you seeing little chance of Atlantic cooling. The Pacific has cooled over the last 17 years while the Atlantic has warmed. It has very little to do with AGW and the North Atlantic will cool just as the North Pacific has.

I should have been clearer about AGW. So long as the Earth has a TOA energy imbalance it is receiving more energy than it is emitting - and therefore will continue to warm. We see evidence on this warming in the global surface temps, of course, but moresignificantly we see it in the long-term OHC trends. There is another thread on recent OHC research so I won't duplicate it here.

I"m also not sure why you say that the Pacific has been cooling for the past 17 years - here's a chart on 1900 - 2010 Indo- Pacific SST trends from a Nature paper

The Pacific appears to warming with a few localized areas of cooling.

Were you instead referring to the PDO? Here's a recent plot:

You do understand, I hope, that the PDO is an oscillation - meaning it is supposed to go up and down in a quasi-periodic fashion. The fact that it's been warm since around 1980 and will enter a cool regime fairly soon doesn't mean anything in a climate change sense. The PDO, and for that matter the AMO, move energy around within the Earth system, they don't alter the amount of energy within the whole Earth system. Only the TOA radiative energy balance warms, or cools, the globe. And, due to AGW, we will keep adding energy to the system for the foreseeable future. Physics tells us we will continue to warm.

[toronto blizzard]

I should have been clearer about AGW. So long as the Earth has a TOA energy imbalance it is receiving more energy than it is emitting - and therefore will continue to warm. We see evidence on this warming in the global surface temps, of course, but moresignificantly we see it in the long-term OHC trends. There is another thread on recent OHC research so I won't duplicate it here.

I"m also not sure why you say that the Pacific has been cooling for the past 17 years - here's a chart on 1900 - 2010 Indo- Pacific SST trends from a Nature paper

The Pacific appears to warming with a few localized areas of cooling.

Were you instead referring to the PDO? Here's a recent plot:

You do understand, I hope, that the PDO is an oscillation - meaning it is supposed to go up and down in a quasi-periodic fashion. The fact that it's been warm since around 1980 and will enter a cool regime fairly soon doesn't mean anything in a climate change sense. The PDO, and for that matter the AMO, move energy around within the Earth system, they don't alter the amount of energy within the whole Earth system. Only the TOA radiative energy balance warms, or cools, the globe. And, due to AGW, we will keep adding energy to the system for the foreseeable future. Physics tells us we will continue to warm.

You really like to ignore the facts don't you Philip. Why do you think that a cold PDO won't influence Climate Change? Is it because you don't want to believe that?

[Isotherm]

You used the detrended AMO chart. I believe that if you use the unadjusted AMO chart the correlation will appear stronger - particularly eartly in the record.

But, as we all know, correlation does not imply causation. The same process that drives the AMO may also be influencing Greenland melting.

If you're saying that the Atlantic will have to cool to historic levels before sea ice will recover and Greenland melting will abate - I agree - but as long as we are adding to AGW by annually dumping gigatons of CO2 into the atmosphere I don't see any hope of that happening.

Correlation does not always imply causation - I agree. However, we have two variables which are very strongly correlated, and the fact that Greenland is surrounded by Atlantic waters lends credence to the notion of the AMO being in control there. It sounds like we're in agreement (I think) on that point.

If by historic levels you mean levels seen in the 1965-1995 AMO cool phase, then I agree. We probably won't flip to negative until 2020-2025 since the warm AMO phase began around 1995. As far as AGW contribution, that is yet to be determined. As we can see from the past century, Greenland temp anomalies have a much stronger correlation to AMO cycling than CO2 trends.

[donsutherland1]

You really like to ignore the facts don't you Philip. Why do you think that a cold PDO won't influence Climate Change? Is it because you don't want to believe that?

Toronto Blizzard,

He's not ignoring the facts. I believe the apparent confusion arises from a lack of delineation between cyclical/interannual variability and long-term climate. Phillip is talking about long-term climate. You're talking about periodic cycles and their impact.

There is an ongoing warming of the climate on a global scale driven by the persistent energy imbalance. That energy imbalance is largely the result of anthropogenic forcings, which have been growing relatively more important as the atmospheric concentration of CO2 increases. As long as the energy imbalance persists, there will be warming.

At the same time, cyclical and interannual variability continues to occur. The flip in the PDO, the emergent El Niño are examples of oceanic cycles that drive such variability. Such variability is occurring, and will continue to occur, but in the context of a warming climate.

[Isotherm]

BTW Greenland temperatures recorded at seaside locals would be expected to be strongly influenced by ocean temps.

Below is a graph of Barent Sea SST to the north of Europe, overlayed with the AMO. Note the tight correlation. AMO is effective up through the waters east and north of Greenland.

[ben4vols]

I should have been clearer about AGW. So long as the Earth has a TOA energy imbalance it is receiving more energy than it is emitting - and therefore will continue to warm. We see evidence on this warming in the global surface temps, of course, but moresignificantly we see it in the long-term OHC trends. There is another thread on recent OHC research so I won't duplicate it here.

The energy imbalance is highly speculative. As Roy Spencer concludes, "at some point we need to ask whether all of this missing warming and energy are missing because they really do not exist".

I"m also not sure why you say that the Pacific has been cooling for the past 17 years - here's a chart on 1900 - 2010 Indo- Pacific SST trends from a Nature paper

The Pacific appears to warming with a few localized areas of cooling.

Were you instead referring to the PDO? Here's a recent plot:

You do understand, I hope, that the PDO is an oscillation - meaning it is supposed to go up and down in a quasi-periodic fashion. The fact that it's been warm since around 1980 and will enter a cool regime fairly soon doesn't mean anything in a climate change sense. The PDO, and for that matter the AMO, move energy around within the Earth system, they don't alter the amount of energy within the whole Earth system. Only the TOA radiative energy balance warms, or cools, the globe. And, due to AGW, we will keep adding energy to the system for the foreseeable future. Physics tells us we will continue to warm.

I say the Pacific hasn't warmed in the last 17 years because it hasn't, it has cooled. Credit to Bob Tisdale for graphs.

Your physics is flawed due to faulty assumptions.

[toronto blizzard]

Toronto Blizzard,

He's not ignoring the facts. I believe the apparent confusion arises from a lack of delineation between cyclical/interannual variability and long-term climate. Phillip is talking about long-term climate. You're talking about periodic cycles and their impact.

There is an ongoing warming of the climate on a global scale driven by the persistent energy imbalance. That energy imbalance is largely the result of anthropogenic forcings, which have been growing relatively more important as the atmospheric concentration of CO2 increases. As long as the energy imbalance persists, there will be warming.

At the same time, cyclical and interannual variability continues to occur. The flip in the PDO, the emergent El Niño are examples of oceanic cycles that drive such variability. Such variability is occurring, and will continue to occur, but in the context of a warming climate.

The energy imbalance is suspect and not known very well. And the cold phase of the PDO will not alter in a warming climate.

[ben4vols]

The energy imbalance is suspect and not known very well. And the cold phase of the PDO will not alter in a warming climate.

Roy Spencer gets in a nice shot with this quote, speaking of Trenberth and his missing energy...

I posted some comments here about my view that the missing energy does not really exist. I also pointed out that they failed to mention that the missing energy over the period since about 2000 was in the reflected sunlight component, not the emitted infrared. This now makes two “missing energy” sources…the other one being the lack of expected warming from increasing carbon dioxide concentrations, which causes a steadily increasing global radiative imbalance in the infrared.

[TerryM]

The answer is in for the 150 year average between Summit melts.

At Summit, the deep ice core (GISP2) reaches a depth of about 3km with the oldest ice being about 123,000 years old. Alley and Anandakrishnan’s paper looks at the ice just below the firn, and into the last 10,000 years. In the past 10,000 years (the Holocene), there is on average a melt layer every 150 years.

This from the gal who was on site doing her doctoral thesis on the firn sections of both NEEM and Summit. The 150 year figure is as accurate at it is misleading. By factoring in the Holocene Maximum a much different figure emerges than would be the case it the last 1,000, 2,000 or even 5,000 year periods were looked at.

The figures I used in the post above were accurate. This is a rare event, that will probably become much less so as AGW continues.

http://www.gisp2.sr.unh.edu/DATA/alley1.html

Terry

[PhillipS]

You really like to ignore the facts don't you Philip. Why do you think that a cold PDO won't influence Climate Change? Is it because you don't want to believe that?

I don't believe I ignore any facts - on the other hand I do ignore a lot of opinion, misinformation, and pseudo-science. Perhaps that's where we differ.

Yes, a cold PDO will have an influence, but that influence will be temporary. A hot PDO has an effect, too. The PDO is an oscillation - it fluctuates above and below some middle value and is therefore incapable of causing a long-term trend in global temps. The Earth has been warming for over a century. The BEST project findings confirmed that trend. Do you deny the reality of that warming trend?

Can you describe any real-world process that would cause only the cold PDO intervals to effect climate change?