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THE Greenland Thread (merged)

For discussions of events and conditions not necessarily related to Peak Oil.

Re: 2013 Arctic Sea Ice

Unread postby Laromi » Mon 17 Jun 2013, 09:54:01

dorlomin wrote:On topic and I am in two minds. The melt has been slower than last year due to colder air and a dominance of low pressure systems. However, while that has been going on, over the past two weeks there has been a lot of lower concentration areas showing up in the central Arctic, towards the Eurasian side. This is mostly surface melt pools rather than open water. But it does point to much thinner ice now being there and as the edge of the ice moves closer in mid July it is likely to have little resistance from these regions. That and most models now pointing to some big high pressures over the central Arctic next week, just in time for solstice.

We could yet get enough melt to set (or near equal) a record.


dormolin, if you have not read the following white paper, may I suggest you do. It is the latest I could find.
A white paper submission to the 2013 Arctic Observing Summit in Vancouver, Canada, April 30-May 2
Understanding Coupled Climate and Weather Processes over the Arctic Ocean:

“Models are critical for understanding climate and climate change. However, current numerical weather and climate models have significant problems in reproducing the current state and are unable to describe observed system interactions”.

“Additionally, these models will likely also be unable to characterize significant shifts in processes or the appearance of new processes as the Arctic continues to change. There is therefore a need for observations to constrain new process-based model parameterizations for improving the basic tools for prediction of weather and sea-ice conditions, as well as for climate projections.”

"Topics [defined by MOSAiC’s] studies include the circulation pathways of the Atlantic and Pacific waters; impacts of wind and atmospheric thermal forcing; freshwater dynamics and life-cycle; Vertical Ocean mixing; and ecosystem primary productivity”.
“Ice growth and melt processes are directly related to energy fluxes, while sea-ice transport is related to momentum fluxes (wind forcing). Model improvements are needed to understand the effects of a changing Arctic on mid-latitude weather and climate. Additionally, better forecasting will be of high value for key economic areas, environmental planning, local populations, and governance in the Arctic.”1

1 A white paper submission to the 2013 Arctic Observing Summit in Vancouver, Canada, April 30-May 2
Understanding Coupled Climate and Weather Processes over the Arctic Ocean: Ola Persson1 , Matthew Shupe1 , Klaus Dethloff2 , and Michael Tjernström3 1 CIRES/NOAA/PSD, University of Colorado, Boulder, CO USA. 2 Alfred Wegener Institute, Potsdam, Germany. 3 Meteorology Dept., University of Stockholm, Stockholm, Sweden. Corresponding Author: Dr. Ola Persson; ola.persson@colorado.edu


"The Arctic Ocean is a region whose changes impact not only the Arctic nations but the entire globe". (pp13) If one accepts that premise it stands to reason one must also ascribe to the hypothesis that Southern and Pacific Ocean transport systems also influence Arctic Ocean.

Which gets us back to my original post of;
Laromi » Mon Jun 10, 2013 5:13 pm It seems to me you have discounted the impact of runoff water. Runoff water, that is, water which drains directly into oceans, rivers and creeks etc. carrying warm ambient water into the ecological system at a much greater rate than say 100 years ago, due to coastal population and construction increases, in the main, and agricultural pursuits.


“In the extra-tropics, the interannual temperature variability is increased with the resolved eddies, and a (sic) notable increases in the amplitude of the El Nino and the Southern Oscillation is also detected. Changes in global temperature anomaly teleconnections and local air-sea feedbacks are also documented and show large changes in ocean-atmosphere coupling. In particular, local air-sea feedbacks are significantly modified by the increased ocean resolution. In the high-resolution simulation in the extra-tropics there is compelling evidence of stronger forcing of the atmosphere by SST variability arising from ocean dynamics”.
Impact of ocean model resolution on CCSM climate simulations http://worldwidescience.org/

You don’t know, I don’t know, nor does science know where GW albeit AGW, is going, or in fact arising from, or do you believe yelling will make everyone believe you are right? Dorlomin, Take time to sniff the flowers, not just look at them.
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Re: 2013 Arctic Sea Ice

Unread postby dorlomin » Mon 17 Jun 2013, 10:19:33

Laromi wrote:dormolin,

Who?
if you have not read the following white paper,
Sorry but that is not a rebuttal or answer to what I have just said.

Its just white noise in fact.

And you failed to provide a link.

However, current numerical weather and climate models have significant problems in reproducing the current state and are unable to describe observed system interactions”.
This is tautological. We have been saying that in this thread for years. You are handwaving, not arguing.


Which gets us back to my original post of;
Laromi » Mon Jun 10, 2013 5:13 pm It seems to me you have discounted the impact of runoff water. Runoff water, that is, water which drains directly into oceans, rivers and creeks etc. carrying warm ambient water into the ecological system at a much greater rate than say 100 years ago, due to coastal population and construction increases, in the main, and agricultural pursuits.

More handwaving.
In the extra-tropics, the interannual temperature variability is increased with the resolved eddies, and a (sic) notable increases in the amplitude of the El Nino and the Southern Oscillation is also detected. Changes in global temperature anomaly teleconnections and local air-sea feedbacks are also documented and show large changes in ocean-atmosphere coupling. In particular, local air-sea feedbacks are significantly modified by the increased ocean resolution. In the high-resolution simulation in the extra-tropics there is compelling evidence of stronger forcing of the atmosphere by SST
Hmmm google search turns this up as the first hit, with no other hits I could find.

You don’t know, I don’t know, nor does science know where GW albeit AGW, is going, or in fact arising from,
[/quote]Stop talking bilge. Posting papers you dont understand, addressing topics we have long dicsussed and waffling and fudging is not holding a discussion.

I have pointed you to the cranks thread, off you pop now.
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And dont forget to smell your flowers.
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Re: 2013 Arctic Sea Ice

Unread postby Laromi » Mon 17 Jun 2013, 11:59:56

dorlomin wrote:
Laromi wrote:dormolin,

Who? Apologies.

if you have not read the following white paper,
Sorry but that is not a rebuttal or answer to what I have just said.


Wasn't meant to be.

And you failed to provide a link.


Too hard for you to type in "WA white paper submission to the 2013 Arctic Observing Summit in Vancouver, Canada" ? oh well here it is; http://www.arcticobservingsummit.org/pd ... search.pdf‎ or of course you could have tried Corresponding Author: Dr. Ola Persson; ola.persson@colorado.edu for "A white paper submission to the 2013 Arctic Observing Summit in Vancouver, Canada. Which was given.

However, current numerical weather and climate models have significant problems in reproducing the current state and are unable to describe observed system interactions”.
This is tautological. We have been saying that in this thread for years. You are handwaving, not arguing.
Well you havn't got far have you?
Dorlomin, Take time to sniff the flowers, not just look at them.
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Re: 2013 Arctic Sea Ice

Unread postby dorlomin » Mon 17 Jun 2013, 12:30:56

Laromi wrote:Too hard for you to type

No. You are the one who has to show where you are getting your quotes from. Not be too lazy to properly link.

And your link is just a normal discussion of the current state of monitoring the Arctic. I have no idea what you think it says, because you seem to have no idea yourself. Certainly you have not explained what you imagine this paper says.

As for the rest of your post, you seem to have made a dogs dinner of the quote function.

Come back when you can work out what it is you are trying to say and not hide behind giant swathes of cut and paste white noise.Otherwise there is a thread just for the quacks like yourself.
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Re: Greenland grapes OTSF 2013 Arctic Sea Ice

Unread postby Ulfr » Sun 23 Jun 2013, 08:50:17

Norse accounts of where grapes were grown should probably take into account some looseness of language. Even in modern Swedish we call currants "vinbär", "wine berries".

Also the moist edges of the Arctic really are green. Much greener and more lush than more southerly climes, because there are essentially two seasons, spring and winter. The cool weather and constant moisture in the "summer" months mean that the grasses are tender and bright green, and the flowers are quite beautiful all summer long. The Arctic can be quite lush for a couple months, in some places.

Iceland is rocky and volcanic. Over time, sheep grazing has made it somewhat more pastoral. When Icelanders moved to the sheltered bays of Greenland, and realized that the grasslands there would support cattle, sheep, and goats
(During that relatively warm spell), they may have called those areas "Greenland", to signal to their fellow Icelanders that this was pastureland.
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Re: THE Greenland Thread (merged)

Unread postby Tanada » Sat 13 Jul 2013, 18:29:35

Based on a study and model of what the Hadley atmospheric cells will do as the Arctic warms we have been having over on the Arctic Sea Ice thread it occurs to me that the assumptions we have all been making about Greenland might be wildly optimistic.

Everyone has assumed that Greenland if it melts at all will melt slowly, taking 300 years to a millennium to melt out and become ice free.

However, this study

http://www.fields.utoronto.ca/programs/ ... ford_W.pdf

models what happens when the Arctic Ocean becomes ice free. In its most basic form when the Arctic Ocean becomes ice free for long enough the Ferrel and Polar atmospheric circulation cells dissipate and the Hadley cell extends from the equator to the North Pole. When that happens the northern hemisphere will be flipped immediately into the hothouse climate state. The last time the Earth was in that configuration, hothouse northern hemisphere and icehouse southern hemisphere was about 5.3 Million ybp. At that time Greenland was ice free, palm trees grew on the southern Greenland coast and the northern half of the island was temperate hardwood forest. Oh yeah, and as a side effect world mean sea level was 25 meters higher than it is today.

Study of Paleo climate data show that doubling CO2 leads to a 3C increase in global mean temperature, however when the Earth is in the unique bi-polar split with the Arctic in the Hothouse and the Antarctic still in the Icehouse that heat is concentrated in the Arctic. During the era 3.5 Million ybp Earth was in this unique state of contrasting hemispheres when the CO2 level was 400 ppmv. Going back to that state in year around CO2 concentration will take place by 2020, and if you count the additional effects from other man made chemicals in the atmosphere the effect already is around 450 ppmv equivalent. So far air pollution has slowed the impact because particulates reflect sunlight and cause a cooling effect, and the massive number of coal power electric plants PRC has built in the last 15 years releases them in massive quantities daily.

Essentially, you do not need the whole 3C temperature increase to cause an ice free Arctic Ocean, and once you have an ice free Arctic Ocean the Hadley circulation cell will expand to cover the entire equator to pole area. That will in turn lead to much more efficient temperature distribution from the equator to the pole and put the north into the Hothouse climate system. Putting Greenland into the temperate climate system as exists in a hemispheric Hadley cell configuration means that the Greenland Ice Sheet will be subjected to above freezing temperatures for six months each year instead of the week or ten days per year it experiences now. That means the GIS will be thinning twenty meters or more each summer, not one, and the melt time estimates are straight out the window. As the ice sheet thins it will expose more dark layers of dust and soot which will feed back and accelerate melting even further. Instead of 300 to 1000 years we could see the GIS collapse in a few decades. Perhaps even in a single human lifetime. All the area that is less than 2000 meters thick glacier would be gone by the end of a century after the Hadley cell switch takes place.

I have spent years poo-poohing these kind of predictions because everyone credible in the scientific community agreed 300-1000 years was the reasonable range of estimates. The GIS alone is over 7 meters of sea level rise. As a side effect of that 7 meter rise several ice areas of Antarctica are modeled to become unstable leading to a rapid additional 18 meters of sea level rise.

The good news, if you want to call it that, is that the two hemisphere's are not in lockstep, when the Northern hemisphere drops into the Hothouse climate system the Southern hemisphere will remain in the Icehouse configuration we currently live in. That means if the climate turns out to be too extreme for humanity in the northern Hothouse there will still be time to stop emitting fossil carbon before we flip the Southern hemisphere into the Hothouse state as well. We are on the cusp of the flip in the North, but the South won't hit the flip until CO2 reaches somewhere between 700 and 850 ppmv.
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Re: THE Greenland Thread (merged)

Unread postby dissident » Sat 13 Jul 2013, 21:01:41

Not to sound like a nitpicker, but the Hadley cell will never extend to the pole on a rotating planet. It's fundamental atmospheric dynamics. Air parcels moving off the equator towards the poles have higher angular momentum than those at high latitudes. The transport is quasi-conservative so strong subtropical jet streams are formed. These jets are perpetually baroclinically unstable since they are being spun up by the continuous transport of angular moment off the equator (that tropical easterlies do not grow without bound tells us that there are processes which restore the angular momentum shipped to higher latitudes). The Ferrel cell is the result of the endless (rather sporadic but never settling down) baroclinic adjustment. Instead of being driven by the release of latent heat and surface heat fluxes, the Ferrel cell is driven by "mechanical" forcing associated with the eddy-mean flow interaction.

(Put another way the Eliassen-Palm flux divergence is an important part of driving the meridional circulation. It would be secondary if only the Hadley circulation was active.)

The only dynamical feature that can "disappear" is the polar front jet. The polar front jet has nothing do with the Hadley circulation and the Ferrel cell(s). There is discussion of the middle latitude temperature gradient change reducing baroclinic instability but this pertains to the middle latitude secondary baroclinic instability of the circulation induced by poleward transport of momentum by eddies spawned from the subtropical jets.

The breakdown of the polar front jet allows more eddy flux into the polar cap region. Baroclinic eddies transport heat (in winter too) and so the warming of the polar regions accelerates.

The last time the Earth was in that configuration, hothouse northern hemisphere and icehouse southern hemisphere was about 5.3 Million ybp. At that time Greenland was ice free, palm trees grew on the southern Greenland coast and the northern half of the island was temperate hardwood forest. Oh yeah, and as a side effect world mean sea level was 25 meters higher than it is today.


I am not sure where you got this. Palm trees grew in Wyoming during the Eocene, i.e. 55 million years ago. The oceans were not 25 meters higher 5.3 million years ago. They were this much higher before the glaciation of Antarctica over 35 million years ago. So I think you are mistaking the period 5.3 million years ago with the Eocene.
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Re: THE Greenland Thread (merged)

Unread postby Tanada » Sat 13 Jul 2013, 22:10:13

dissident, please read the pdf I linked to in the earlier post and then get back to me, they are modeling the situation and say that there is a stable hothouse state where only the Hadley cell exists.

As for the sea level issue, sea levels were 70 meters higher during the PETM, not 25. 3 Million ybp they were 10 to 20 meters higher depending on who you trust and who has the best estimates. 7 of those 10 to 20 came from Greenland, almost all of the rest had to come from Antarctica because all the mountain glaciers together only make about half a meter. 25 for the hothouse north is likely an over estimate, the 10 to 20 estimate comes from Dr. David Archer's book The Long Thaw. On the other hand the 10-20 is for 3 Million ybp and sea levels were a little higher at 5.3 Million ybp, but its kind of beside the point from what I was trying to communicate.
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Re: THE Greenland Thread (merged)

Unread postby ritter » Tue 16 Jul 2013, 11:10:09

Tanada wrote:I have spent years poo-poohing these kind of predictions because everyone credible in the scientific community agreed 300-1000 years was the reasonable range of estimates. The GIS alone is over 7 meters of sea level rise. As a side effect of that 7 meter rise several ice areas of Antarctica are modeled to become unstable leading to a rapid additional 18 meters of sea level rise.


So, to use your words, when does the poo-poohing hit the fan? Timing in this event is everything. As you well know, we are moving this climate train along far to fast for most species to adapt to it (likely including us). Once the Arctic goes ice free (or essential so), when does the shift happen? I guess that's the million dollar question.
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Re: THE Greenland Thread (merged)

Unread postby Tanada » Tue 16 Jul 2013, 12:06:26

ritter wrote:
Tanada wrote:I have spent years poo-poohing these kind of predictions because everyone credible in the scientific community agreed 300-1000 years was the reasonable range of estimates. The GIS alone is over 7 meters of sea level rise. As a side effect of that 7 meter rise several ice areas of Antarctica are modeled to become unstable leading to a rapid additional 18 meters of sea level rise.


So, to use your words, when does the poo-poohing hit the fan? Timing in this event is everything. As you well know, we are moving this climate train along far to fast for most species to adapt to it (likely including us). Once the Arctic goes ice free (or essential so), when does the shift happen? I guess that's the million dollar question.


I don't expect it this year or next, and I hope it is far in the future. However the pdf I cited above was enough to make me think it just might happen in my lifetime, and that is kind of unnerving.
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Re: THE Greenland Thread (merged)

Unread postby ritter » Tue 16 Jul 2013, 15:48:00

Tanada wrote:I don't expect it this year or next, and I hope it is far in the future. However the pdf I cited above was enough to make me think it just might happen in my lifetime, and that is kind of unnerving.


"Kind of unnerving" is an understatement! It certainly seems that the climate shift is accelerating, doesn't it? Nearly all studies expect more and sooner than even 5-10 years ago.
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Re: THE Greenland Thread (merged)

Unread postby Graeme » Fri 19 Jul 2013, 18:58:58

Like Butter: Study Explains Surprising Acceleration Of Greenland’s Inland Ice

Last November, a major international study in the journal Science found that the Greenland ice sheet’s melt rate was up nearly 5-fold since the mid-1990s.

This acceleration has put ice sheet loss far ahead of what most climate models had predicted several years ago. Now a new study by scientists at the Cooperative Institute for Research in Environmental Sciences (CIRES) in the Journal of Geophysical Research: Earth Surface explains at least one key factor the models have missed:

Surface meltwater draining through cracks in an ice sheet can warm the sheet from the inside, softening the ice and letting it flow faster.

The study notes that not only has the Greenland ice sheet accelerated at the edges where they flow into the ocean, but the “interior regions are also flowing much faster than they were in the winter of 2000-2001.”

To shed light on the observed acceleration, [Lead author Thomas] Phillips and his team developed a new model to investigate the effects of meltwater on the ice sheet’s physical properties. The team found that meltwater warms the ice sheet, which then—like a warm stick of butter—softens, deforms, and flows faster.

Previous studies estimated that it would take centuries to millennia for new climates to increase the temperature deep within ice sheets. But when the influence of meltwater is considered, warming can occur within decades and, thus, produce rapid accelerations.

Coauthor William Colgan explained, “The model shows that a slight warming of the ice near the ice sheet bed—only a couple of degrees Celsius—is sufficient to explain the widespread acceleration.”

The findings have important ramifications for ice sheets and glaciers everywhere. “It could imply that ice sheets can discharge ice into the ocean far more rapidly than currently estimated,” Phillips said. “It also means that the glaciers are not finished accelerating and may continue to accelerate for a while. As the area experiencing melt expands inland, the acceleration may be observed farther inland.”


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Re: THE Greenland Thread (merged)

Unread postby Subjectivist » Fri 19 Jul 2013, 19:03:57

Whatever happened to all those off shore Greenland oil wells Denmark was suppossed to be producing from this decade?
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Re: THE Greenland Thread (merged)

Unread postby csnavywx » Sun 28 Jul 2013, 09:39:48

Tanada wrote:dissident, please read the pdf I linked to in the earlier post and then get back to me, they are modeling the situation and say that there is a stable hothouse state where only the Hadley cell exists.

As for the sea level issue, sea levels were 70 meters higher during the PETM, not 25. 3 Million ybp they were 10 to 20 meters higher depending on who you trust and who has the best estimates. 7 of those 10 to 20 came from Greenland, almost all of the rest had to come from Antarctica because all the mountain glaciers together only make about half a meter. 25 for the hothouse north is likely an over estimate, the 10 to 20 estimate comes from Dr. David Archer's book The Long Thaw. On the other hand the 10-20 is for 3 Million ybp and sea levels were a little higher at 5.3 Million ybp, but its kind of beside the point from what I was trying to communicate.


One problem I see with this is that massive increases in meltwater and icebergs emanating from the GIS will have a freshening and cooling effect on the northern Atlantic, similar to a Heinrich event. In fact, as long as significant melt continued, this would constitute a significant negative feedback to NH temperature (especially regionally). "Climate flickering" would be the rule instead of a steady transition.
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Re: THE Greenland Thread (merged)

Unread postby Tanada » Sun 28 Jul 2013, 14:38:43

csnavywx wrote:One problem I see with this is that massive increases in meltwater and icebergs emanating from the GIS will have a freshening and cooling effect on the northern Atlantic, similar to a Heinrich event. In fact, as long as significant melt continued, this would constitute a significant negative feedback to NH temperature (especially regionally). "Climate flickering" would be the rule instead of a steady transition.


I am not sure you can compare this to a Heinrich event, after all the floating ice around Greenland has already retreated quite a lot and by the time the Arctic Sea is actually ice free in late Spring or early Summer it is likely there won't be any floating ice left around the island. That pretty much eliminates the possibility of icebergs, the ice has to be floating or very close to the edge of the water to float away as an Iceberg of any sort.

As for the melt water water I don't think even in the worst case scenario that it would add up to much more than a large river of influx, and a great deal depends on where it leaves the island and enters the sea. Most of the maps I have seen show the bedrock under the GIS as being below sea level with the exit point being on the west by south west coast. If that is an accurate forecast the drainage of fresh water would flow the same direction, pouring out into the gulf north of Newfoundland island. I think, though of course nobody knows for certain, that it would have plenty of time to mix with the sea water before it could interfere with the Gulf Stream very much.

Even if it did lead to the climate flicker you are thinking of, that flicker was a condition that came about in the Icehouse climate. Would such a condition even be possible in the Hothouse climate state? Hothouse climate depends on the Ferrel cells extending all the way to the Pole, not on the water currents much at all. If the Ferrel cell is over Europe extending into the Arctic then there is no particular need for gulf stream water to export heat into Europe, it already has all it needs from the Atmosphere.

Even if the Ferrel cell shifted tomorrow the Greenland Ice Sheet is still a couple of kilometers high and cold, it would be a cold high altitude region until the ice melted away and even at a meter per weeks that would take 5 years or so.
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Re: THE Greenland Thread (merged)

Unread postby csnavywx » Mon 29 Jul 2013, 15:08:49

http://www.columbia.edu/~jeh1/mailings/ ... Update.pdf

A little tie in with my previous post.

I actually agree that it isn't the same as an ice-age Heinrich event and that Greenland is relatively small potatoes compared to say.. the ancient Laurentide Ice Sheet or the WAIS (where most of the concern is now). However, icebergs are discharged from these deep fjords where the outlet glaciers are currently. You don't have to have a big ice shelf to get a lot of bergs, just a large, fast-moving outlet glacier with access to the ocean. They can quite easily make it out into the North Atlantic from western outlet glaciers (such as Jacobshavn) as well.
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Re: 2013 Arctic Sea Ice

Unread postby dohboi » Tue 30 Jul 2013, 17:36:09

This is on Arctic ice, though not sea ice. Neven has a new blog post Greenland Ice Sheet: "Starting to Slip".

http://neven1.typepad.com/blog/2013/07/ ... -slip.html

Good video with many of the scientists we have been following.

ETA: It's not till you get to the third video that Greenland ice melt comes up, and that seems to be a video from last year. I have to assume that he meant to link to the video at this link:

http://www.yaleclimatemediaforum.org/20 ... ice-sheet/
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Re: 2013 Arctic Sea Ice

Unread postby dorlomin » Wed 31 Jul 2013, 05:17:54

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Re: THE Greenland Thread (merged)

Unread postby dissident » Thu 01 Aug 2013, 10:07:05

Tanada wrote:dissident, please read the pdf I linked to in the earlier post and then get back to me, they are modeling the situation and say that there is a stable hothouse state where only the Hadley cell exists.


Once again, some presentation pdf or ppt is sowing confusion on the web about basic atmospheric physics.

In this case I think these idealized modeling people are doing everyone a disservice with their academic games. In this case they impose a pole-equator delta T via a specified background state. So they are shutting down barcolinic activity via a deus ex machina mechanism. In the real world, the delta T is not an external parameter but imposed by the baroclinic activity itself. So if the surface temperature manages to evolve towards their idealized state, then the very process that maintains it will disappear and a stronger gradient will re-establish itself via radiative transfer (the cooling at the pole will not disappear for any accessible CO2 and H2O regime).

As for the sea level issue, sea levels were 70 meters higher during the PETM, not 25. 3 Million ybp they were 10 to 20 meters higher depending on who you trust and who has the best estimates. 7 of those 10 to 20 came from Greenland, almost all of the rest had to come from Antarctica because all the mountain glaciers together only make about half a meter. 25 for the hothouse north is likely an over estimate, the 10 to 20 estimate comes from Dr. David Archer's book The Long Thaw. On the other hand the 10-20 is for 3 Million ybp and sea levels were a little higher at 5.3 Million ybp, but its kind of beside the point from what I was trying to communicate.


I have made the point several times on this board before: comparing the climate sensitivity to CO2 increases today and 5.3 million years ago is not appropriate. We slipped into an ice age because the Panama channel closed and due to ocean currents around Indonesia about 5 million years ago and not because the CO2 was removed by some unknown process. So 450 ppmv CO2 today will have a different impact than it did 5 or 10 million years ago. From the paleclimate record there will be a smaller temperature response with today's sensitivity.
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Re: THE Greenland Thread (merged)

Unread postby Subjectivist » Mon 18 Nov 2013, 17:31:22

dissident wrote:
I have made the point several times on this board before: comparing the climate sensitivity to CO2 increases today and 5.3 million years ago is not appropriate. We slipped into an ice age because the Panama channel closed and due to ocean currents around Indonesia about 5 million years ago and not because the CO2 was removed by some unknown process. So 450 ppmv CO2 today will have a different impact than it did 5 or 10 million years ago. From the paleclimate record there will be a smaller temperature response with today's sensitivity.


Really? How much smaller do you believe the response will be? So far from the effects we see in the Arctic the amplification has been higher than what the climate models were predicting, not smaller.
II Chronicles 7:14 if my people, who are called by my name, will humble themselves and pray and seek my face and turn from their wicked ways, then I will hear from heaven, and I will forgive their sin and will heal their land.
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