Jump to content
Snow?
Local
Radar
Cold?
IGNORED

Greenland - What Do We Know, What Is The Long Term Future And Is There Any Evidence Of A Melt Out?


pottyprof

Recommended Posts

Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

The latest NOAA image posted in this thread would suggest it will happen in the next couple of weeks or so....I think perhaps the Sun is going to fall from the sky too and the Cat in the Hat is going to emerge as the world leader, romping home in the Presidential Election.

http://forum.netweat...3/page__st__840

As I've said many times before the scale of the event leading to the interuption in the Drift was of such a scale as to render that impossible today. Even if the whole of Greenland turned into a huge ice lake we would spordically drain it to avoid such a dam collapse issue would we not?

As we see with the feed Glaciers much of the melting is in-situ at the base of the ice. The 'basin' nature of Greenlands topography would have me imagine that , once inundated, the base of the ice would melt in-situ and the water out from melt would not be a surface feature?

Catlin showed us that melt is allowing an exchange of top waters into the depth within the basin so we may even find that the drift shifts far greater amounts of water as it inades further into the Basin (could the 'Laptev Bite' be a summer extension of the NAD bouncing off the russian land mass and back into the central ice mass???).

All we know is warm seeks to balance out cold and cold to chill the warm. If we get more warm added into the system how can you expect cooling?

Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

As I've said many times before the scale of the event leading to the interuption in the Drift was of such a scale as to render that impossible today. Even if the whole of Greenland turned into a huge ice lake we would spordically drain it to avoid such a dam collapse issue would we not?

Not everone agrees with that (Summerhayes and Thorpe, "Oceanography-An Illustrated Guide) because the Laurentide Ice Sheet is only one of several theories about what exactly led to the shut down of the conveyer.

The fresh water input weakens the thermohaline circulation, which makes the circulation more susceptible to further weakening. This process has been investigated in recent years using mathematical models of ocean circulation. The models show that there are a number of different states of the thermohaline circulation, some of which are stable There are, however, transitions between stable states, which occur over periods as short as 40 years. It has been speculated that the present North Atlantic Ocean may be close to one of these transitional states, of which the Younger Dryas is an example.

One study has suggested that the transition between states is not necessarily symmetrical. The change from strong to weak thermohaline circulation may be more rapid (40 years) than the re-establishment of the strong circulation (500 years). Further study of the Younger Dryas and similar events in the palaeoclimate record may give us important clues to the likely response of the present -day themohaline circulation in the North Atlantic to global warming. (remaining stable or 'flipping' to another state).

I remember discussing this same subject years ago with Dr. Jon. Shanklin (of ozone fame) on one of his visits to Camborne, Or rather I listened. At the time he thought he thought it a possibility but unlikely under the current global warming scenario. I would certainly be interested in his opinion now.

(a) The 'present-day' North Atlantic with a vigorous conveyor (thermohaline) circulation, and a large northward transfer of heat. (b The 'ice-age' North Atlantic with a weak conveyor (thermohaline) circulation, and a reduced northward heat transfer. The northern North Atlantic was therefore cooler and fresher than the 'present-day' ocean. The extended sea-ice cover is associated with a fresher surface layer, which stabilises the water column and inhibits deep convection.

post-12275-0-42840900-1351862723_thumb.j

Edited by knocker
Link to comment
Share on other sites

Regarding disruption of the thermohaline circulation and North Atlantic Drift, it is not totally clear that this would happen or to what extent.

The Eemian warm period 125,000 years ago is often used as a parallel for warming in the Holocene today, lasting for 10,000 years and with Greenland and Arctic temperatures that were up to 5°c warmer than today. This was enough to melt substantial parts of Greenland and it was thought to be the last time that the Arctic was ice free.

However in recent research, samples from the Nordic sea show the Arctic was still cold enough for ice, and meltwater reduced the effect of the Atlantic drift in this region.

But the North Atlantic to the west of the British Isles was warmer and 'overheating' with continuing oceanic heat transfer from the south.

Press release summary - "Warm climate - cold arctic?"

http://www.geomar.de...aeltere-arktis/

Paper - "Contrasting ocean changes between the subpolar and polar North Atlantic during the past 135 ka"

http://www.leif.org/...012GL051800.pdf

Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

A different perspective. A salt oscillator in the glacial Allantic.

http://www.whoi.edu/science/GG/paleoseminar/pdf/broecker90.pdf

But for the full paper on this.

A salt oscillator in the glacial Atlantic? 2. A “scale analysis†model

Abstract.

A proposal has been made by Broecker et al. (1990) that rapid changes on a time scale of a thousand years or so, seen over much of the last major glacial in the Greenland ice core record, represent significant climate changes and are caused by a salt oscillator in the glacial Atlantic. This proposal is examined in terms of a rudimentary quantitative model. Scale analysis asserts that heat transported to the high-latitude atmosphere when the thermohaline circulation is turned on, is large enough to produce the melting rates found by Fairbanks (1989) for the time interval around that of the Younger Dryas event and that these melting rates are of the same order of magnitude as the mass flux associated with water vapor flux to the Pacific Ocean estimated by Broecker (1989). Scale analysis also suggests that the salinity fluxes associated with 1) the water vapor flux mechanism, 2) the rapid melting episodes of Fairbanks, 3) possibly ice sheet growth events, 4) net transport by the thermohaline circulation and 5) net transport by turbulent eddy mixing are roughly of the same order of magnitude and therefore may be important mechanisms for producing salinity oscillations on a time scale of a few thousands of years, (see Broecker, 1990). By integration of simple salt conservation equations, it is found that model oscillations with a period of a few thousand years occur over a significant range of salinity fluxes; estimated fluxes fall well within the range for which oscillations exist. The model also suggests that there may exist close coupling between the European-Scandinavian ice sheets and the bimodal response of the oscillator; that is, significant increases or decreases in continental ice volume may accompany each complete cycle of the oscillator. In addition, it appears that continental ice may be required for the salt oscillator to function. A crucial element, which cannot adequately be investigated with the present model, concerns the local effect of salinity source/sinks associated with melt water production. The proximity of these source regions on the neighboring ice sheets to the local regions where production of deep water occurs may play a critical role in the functioning of the proposed salt oscillator. In addition, further treatment of thermodynamics is needed to investigate the feasibility of a salinity driven oscillator.

http://www.agu.org/pubs/crossref/1990/PA005i006p00835.shtml

Link to comment
Share on other sites

  • 2 weeks later...
Posted
  • Location: Camborne
  • Location: Camborne

Just a note on the Greenland albedo. Can't remember whether I've posted this before or not.

Greenland ice reflectivity continues dropping at highest elevations

An 6 August, 2012 updated compilation of NASA MODIS observations of Greenland ice sheet reflectivity (a.k.a. albedo) indicate that through the 2012 melt season, beginning ~28 May, the ice sheet has remained in a darkened state as in 2011 and 2010.

Remaining in this condition, the ice sheet has absorbed ~200 Exajoules more solar energy for June-July, more than twice the US annual energy consumption, in a self-reinforcing feedback loop. For July, the 100 Exajoules more energy absorption is sufficient, for example to melt 136 Gt of ice at a temperature of 0 deg C. The 2003-09 average annual loss rate was 250 Gt [[1]]. But, not all of the energy goes into melting. Another way to think of this additional energy flux is that it is sufficient to bring to the melting point a 9 cm thick layer of ice sheet accumulation area snow having a temperature of -10 C. In reality, the increased energy is disposed by some combination of melting and snowpack heating.

The key aspect about albedo change is that it that amplifies the effect of 1.) warming and 2.) black carbon loading. The impact is felt in terms of snowpack heating and melt. Because both albedo is low and air temperatures are high summer 2012, we know that an exceptional, record setting melt season is underway.

Perhaps most remarkable about the 2012 pattern is how much darker the snow has been in the higher elevation net snow accumulation area. June and July monthly average reflectivity is below the 2000-2011 average across the southern-central area where surface elevations are above 2,000 m (6,561 feet). A purple area about 1/4 the distance north of the ice sheet southern tip at an elevation of 2,400 m (7,874 ft) has reflectivity 0.07 or 7% below the already declining 2000-2011 June (12 year) average.

http://bprc.osu.edu/wiki/Greenland_Ice_Albedo_Monitoring

Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

UW Professor’s Delayed Greenland Ice Melt Research Published in Nature

November 8, 2012 — Neil Humphrey agrees there’s no denying that the Greenland Ice Sheet is melting. But he and other scientists who have recently documented surface melt of the country contend Greenland is melting at a slower rate than the current world consensus of scientific thought.

Humphrey, a University of Wyoming professor of geology & geophysics, co-wrote a paper with four other researchers that contends this point. The paper, titled “Greenland Ice Sheet Contribution to Sea Level Rise Buffered by Meltwater Storage in Firn,†will appear in today’s issue (Nov. 8 of Nature.

“We’re not saying Greenland is not melting,†Humphrey says. “What we’re saying is it will be one to two decades longer before we start seeing the melt.â€

That’s because Humphrey and other researchers’ data -- collected on the western flank of the Greenland Ice Sheet from 2007-2009 -- shows that the water generated by repeated recent melt events penetrates deeply into the snow and firn (partially compact snow). This fills the pore space and diminishes the amount of meltwater that actually runs off into the ocean.

As future surface melt intensifies due to Arctic warming, a fraction of meltwater -- that would otherwise add to the rise in sea levels -- fills tens of meters of existing pore space of the percolation zone. The percolation zone is a region of the accumulation area that is perennially covered by snow and firn, Humphrey says.

“The snow is so deep and so cold that, even though it’s melting, the melt infiltrates into the lower, colder snow and refreezes,†Humphrey says. “We calculate there is one to two decades of pore space within the snowpack. You get denser snowpack. After 10 or 20 years, it (the pore space) fills up.â€

Thus, the routing of surface meltwater -- that fills the pore space of the partially compacted snow -- acts as a buffer between climate warning and sea-level response. As a result, this delays expansion of the ice sheet area contributing to sea-level rise.

“While other people (scientists) are predicting up to a one-half foot sea rise by 2050, we’re actually saying our data shows that any rise that will occur will be delayed by one or two decades,†says Humphrey of the paper he termed as “controversial.†“A half-foot rise is significant. Half of Florida would be under water. New Orleans would be gone.â€

http://www.uwyo.edu/...-in-nature.html

Edited by knocker
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

This of course was inevitable.

I watched the astounding film about global warming and the world’s melting glaciers, Chasing Ice, at the Woodstock Film Festival last month. Part of the jaw-dropping documentary about National Geographic explorer and environmental advocate, James Balog, was filmed in breathtaking Greenland—the largest island in the world, and a self-ruling overseas territory of Denmark.

Greenland’s vast, pristine, virtually-untouched terrain is becoming a hotbed for resource extraction. The Arctic is melting at an unprecedented rate, making Greenland’s natural resources, including high demand commodities such as oil, gas, gold, iron, copper and rare earth metals, more accessible. Insatiable international oil, gas and mining conglomerates are now aggressively vying to control access to the riches glaciers once denied.

“This is not just a region of ice and polar bears,†Prime Minister of Greenland, Kuupik Kleist, told Reutersin the capital Nuuk, formerly known by its Danish name Godthab. “Developing countries are interested in a more political role in opening up of the Arctic. Greenland could serve as a stepping stone.â€

Posted Image

http://ecowatch.org/...e-earth-metals/

For some interesting photos of the famous Black Angel zinc mine.

http://www.aditnow.co.uk/album/Black-Angel-Zinc-Mine-User-Album/

Edited by knocker
Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne


Warming Temperatures Will Change Greenland’s Face
CCNY scientist constructs fine-scale projections of how warming will alter the island

Global climate models abound. What is harder to pin down, however, is how a warmer global temperature might affect any specific region on Earth.

Dr. Marco Tedesco, associate professor of earth and atmospheric sciences at The City College of New York, and a colleague have made the global local. Using a regional climate model and the output of three global climate models, they can predict how different greenhouse gas scenarios would change the face of Greenland over the next century and how this would impact sea level rise.

The resulting fine-scale model gives a high-resolution picture of the island’s future. “We put Greenland under a microscope to see what accounts for melting and for ice mass changes in different regions,†said Professor Tedesco.

He and his colleague, Xavier Fettweis of the University of Liege, Belgium, reported their results online November 8 in “Environmental Research Letters.â€

They compared two possible future CO2 scenarios: a concentration of carbon dioxide in the atmosphere projected for the end of the century of 850 parts per million (ppm) versus a more aggressive projection of 1370 ppm. The first approximates the current rate of increase.

The Greenland ice sheet would lose more ice and snow to melting than it would accumulate in both scenarios. Basins on the southwest and north coasts would suffer the greatest losses. Temperatures would only have to increase by 0.6 to 2.16 degrees Celsius (1.8-3.9 ° F) to tip the balance into more loss than gain.

The new model shows how a melting would alter the topography of “one of the world’s refrigerators,†potentially affecting adjacent ocean circulation and salinity, and speeding further melting.


http://iopscience.iop.org/1748-9326/7/4/045405/pdf/1748-9326_7_4_045405.pdf

Link to comment
Share on other sites

  • 3 weeks later...
Posted
  • Location: Camborne
  • Location: Camborne

Updated results for the whole 2012 melting season in Greenland, including total mass loss from GRACE.

Overall, in 2012 ALL of the considered parameters (albedo, bare ice, surface mass balance, melting, total mass change, etc.) set a new record !

http://www.the-cryosphere-discuss.net/6/4939/2012/tcd-6-4939-2012.pdf

Link to comment
Share on other sites

Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

According to some records are only there to be broken and do not signify anything? Be it temp records in USA this year or every single Arctic ice record or global ice min record etc etc.

We knew it would be bad but this bad?

When you look at the NAO you have to wonder at how it mirrors ice loss through the noughties? Any such peak through the 30's and 40's would set me wondering for sure!

Enough folk opined that the 07% loss was just a 'cyclic' event. They even made up a period for the cycle including one other instance of melt at summit. Next year will be interesting as both the NAO and the H.P, seem to be a thing in growth and so we may well expect even worse next year?

Though gallows humour it is becomeing amusing to watch the folk, in denial, scrabble from one disaster to the next popping up an excuse as to why it is a 'normal' ,natural, AGW unaffected event.

I sense the fun is only beginning though?

Anyone know why Mr Watts stayed moot on the record global ice min by the way? He seemed keen on ice records a few weeks back??

Link to comment
Share on other sites

Posted
  • Location: Swallownest, Sheffield 83m ASL
  • Location: Swallownest, Sheffield 83m ASL

Though gallows humour it is becomeing amusing to watch the folk, in denial, scrabble from one disaster to the next popping up an excuse as to why it is a 'normal' ,natural, AGW unaffected event.

And we're still colder than the law of averages say we should be, according to most figures. Unless of course they are wrong?.... Stats are a wonderful thing.

  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

To avoid confusion the science moved from 'warming' to climate shift seeing as folk were not understanding that some places would suffer from the cold now free to escape the arctic as the planet warms in the ways predicted (poles most and first) lessening the temp grad twixt equator and pole and slowing the girdle like flow of the polar jet.

As long as the 'average' is still higher than the old global average we will suffer the slow unwinding of a warming world? We are now beginning to see Greenland starting to speed up it's ice losses. We Now see even the enhanced snowfall, that a warmer atmosphere carrying more moisture brings, overtaken by mass loss and so it will be in the wider world. Folk focusing on changes over areas receiving more precipitation (and cloud and cold brought down with the rain) or polar prolapses can not ignore the more startling changes across areas that are rapidly warming? Only in late Nov the northern most weather station in Greenland was in plus c temps instead of the average -25c that that day of the year?

Which is more stunning a few degrees cooler or twenty odd degrees warmer?

Which is the most damaging? A cold wet day in temperate regions or permafrost/ice melting days across the Arctic circle?

The answer is easy and inescapable.

Link to comment
Share on other sites

Posted
  • Location: Swallownest, Sheffield 83m ASL
  • Location: Swallownest, Sheffield 83m ASL

Perhaps the worst of the global warming is yet to arrive here.

We are living in a world that at the moment is in an anomalous state. We are currently well below where we should be regarding temperature. Even GW admits that, probably for different reasons but it is a fact as we know and understand it. The planet has to warm up to get back to normal. We have been giving it a push and may or may not have overridden a few safety features along the way but yes, ice will melt and Greenland will live up to it's name once more. Doncaster by the sea will probably never be the best seaside town but at least it would get a wash twice a day....... Edited by pottyprof
  • Like 1
Link to comment
Share on other sites

Posted
  • Location: South Yorkshire
  • Location: South Yorkshire

To avoid confusion the science moved from 'warming' to climate shift seeing as folk were not understanding that some places would suffer from the cold now free to escape the arctic as the planet warms in the ways predicted (poles most and first) lessening the temp grad twixt equator and pole and slowing the girdle like flow of the polar jet.

Nonsense! The 'warming' bit was dropped when they realised they'd been rumbled, otherwise they'd have got the handle right first time around. Sheesh,you're really hard work,GW!

Link to comment
Share on other sites

Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

Global warming is just that 'global warming'. The forcings for this have been increasing for 150yrs but that does not mean that it is strong enough to overcome it's own counterpart (Dimming) or the long cycle cool drivers of the planet yet.

I number myself among those who see a time when 'warming' will be the only signal to be measured with cool drivers not impacting the rises in temp as they are still able to do today. I also feel that this is the final period of negative impact on the warming that the planet will see with too many other factors now coming into play (natural dormant carbon cycle additions from the permafrost /ice sheets, global dimming dropping out, albedo shift across the north with warming of the remnant ice age chilled Arctic Ocean, expansion of the tropics and loss of the polar jet, desertification of tropical rainforest's with the expansion of the 'desert zone').

The ongoing mixing out of the Arctic cold over summer and winter is already leading to some fantastic temp highs being set across the Arctic and these are not matched by exceptional lows across the temperate region. If you imagine the area of the pole you will see how 'diluted' any cold plunge would have to be to impact all of the temperate Zone of the planet. conversely small WAA can cover huge areas of the pole. Where once, in the early noughties, temp anoms of +30c could only be found over open water that should have been frozen (Kara/Barrentsz) we now see those extremes impacting Svalbard,Greenland, North slope Alaska, Siberia and Northern Canada. Only a couple of weeks back we saw the temp record for the most northerly weather station in Greenland fall with a 27c anom over the average for that time of year. If models keep the same trend then we will see a subtropical airmass impacting Kara/Barrentsz from the 13th of December threatening to swamp Svalbard's record temps of last Feb?

I think maybe you need to pull back and take a wider view of the 'warming' L.G.? From a low start temp the global average has risen to now be in the top ten global temps and that is with a Nina start to the year (2012 looks to take the 2011 record of being the warmest Nina year on record? according to the NOAA). Even allowing for 'Natural cool drivers' running the show and global dimming shaving off over 5% of the incoming Solar top ten global temps do not look like a cool-down to me?

More folk appear to be of the opinion that the PDO-ve is well past half over and are now wondering what positive drivers will do to temps esp. if we are dealing with Dimming issues at the same time?

With all of Greenland's records for melt smashed in 2012 what impact will a global record temp year have there?

With ice loss now placing clear blue skies over southern Greenland for most of the year, via the H.P. we see lodged there (the one that pushed Sandy into N.Y.?) , how long will this years records last???

The last 'gap' was from 2010's record year, maybe we will now see back to back record loss years from now on?

With the global ice min record broken a few weeks back and P.I.G. only waiting for a tide/storm to loose the glacier front 2012 looks like a global land ice loss year too (when you look at Peterman's losses and add in the snouts from all the glaciers along the N.Shore of Greenland this summer and the acceleration of mass loss from Greenland and Antarctica). Not bad for a 'cooling/Flat-lined' Global temp (or am I missing something here?)

Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

Greenland ice sheet carries evidence of increased atmospheric acidity

Research has shown a decrease in levels of the isotope nitrogen-15 in core samples from Greenland ice starting around the time of the Industrial Revolution. The decrease has been attributed to a corresponding increase in nitrates associated with the burning of fossil fuels.

However, new University of Washington research suggests that the decline in nitrogen-15 is more directly related to increased acidity in the atmosphere.

http://www.washington.edu/news/2012/12/07/greenland-ice-sheet-carries-evidence-of-increased-atmospheric-acidity/

Link to comment
Share on other sites

Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

Acid snow then?

I believe that some of our posters , who like to claim neutrality, will be exposed for what they are by the way they favour press releases that purport to bring "good news" well outside the umbrella of current research.

One instance , I have my eye on, was a paper released in 2010 claiming that Greenland melt was looking 'cyclical' in nature and that 2010 was a peak year in the current cycle? Even though, at the time of release in 2011 the melt was looking bad certain posters were trying to push the paper as 'the truth' Whilst all the data was screaming of an acceleration in melt.

We now have the figures to show a trend of melt doubling over a 4 year cycle (I told you that the data was 'screaming'?) and I believe that the past years plummet in albedo and the snow/ice loss forcing of the H.P. cell over southern Greenland indicates that we are now set to see the 'flood gates' open and rates start to increase further than we have seen through the noughties. If I am correct then next years melt will see an increase in ice mass loss. If ice and snow loss are forcing the pressure patterns/positioning then we will also see another melt at Summit over summer and a bad (extreme?) start to the year for Eastern USA with a continuation of drought and high temps into spring driven by the H.P. that gave Sandy the 'left hook' potential.

Edited by Gray-Wolf
Link to comment
Share on other sites

Posted
  • Location: Cheddar Valley, 20mtrs asl
  • Weather Preferences: Snow and lots of it or warm and sunny, no mediocre dross
  • Location: Cheddar Valley, 20mtrs asl

And I remember you pushing a paper from Serenze and his death spiral at every available opportunity. At least he had the decency to retract and apologise for his excited haste....

By all means criticise scientific papers, but criticise folk for having faith in peer reviewed papers???? Are you seriously suggesting that the only peer reviewed stuff which should be listened to and noted are ones you agree with, or ones which show what you want them to show?

I'm pretty sure the basis for all science is one of progression, a paper published this year about any given subject may well be super ceded next year if more information/evidence is available to study. No science is set in stone, least of all, climate science. Criticising that process (as you do above) either reveals you do not appreciate how science progresses or demonstrates a desire to bicker just for the sake of it - neither one of those options does your stance or argument in favour of AGW any favours.

Link to comment
Share on other sites

Posted
  • Location: Camborne
  • Location: Camborne

Greenland Ice Sheet outlet glaciers: Zebras no more

Overall in Greenland, the rate of area loss in marine-terminating glaciers during the 2010 melt season (419 km2) was 3.4 times that of the previous 8 years. There is now clear evidence that the ice area loss rate of the past decade (averaging 120 km2/year) is greater than loss rates pre-2000. The exceptional extension of the ablation season in 2010 in southern Greenland indicates the vulnerability of these areas to expanded melt regions (Box et al, 2010).

The amazing aspect of Greenland glaciers is that (despite the specific variation in type, location specific fjord configuration, etc) their response has been as uniform and synchronous to global warming as has been observed. If this warming of the world persists long enough, the ice “banks†of Greenland will begin to fail. Those with the greatest reserves on their asset sheets and the fastest turnover, and thus having the greatest potential contributions to sea level rise over time, are:

  • In the north, Zachariae (and to a lesser extent, Petermann)
  • The fast flowing marine terminating outlet glaciers of western and southeast Greenland (Rinks, Umiamako, Helheim, Jakobshavn, Epiq Sermia and Kangerdlussaq)
http://www.skeptical...d_Glaciers.html
Link to comment
Share on other sites

Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

When we hear scientist telling us that Greenland now sees a 'doubling' of losses every 4 years it really makes you think! When I was discussing ice loss there in 07' and 08' folk where referring me to studies through the 90's to support their arguments whilst I was only able to go off snippets of 'fact' from reports and anecdotal evidence from teams returning from the field. It would appear that those teams and snippets were of quality and the info useful.

With a 4 year turnover how can folk expect me to entertain wishes for a 15 or 30 year study so we can see the trend? Where will we be in 30yrs with the current rate of loss acceleration???

I imagine the same will be true of West Antarctica now the 'girdle' of shelfs holding back the ice there has failed and both Greenland and West Antarctica will give us a good feel for how fast East Antarctica will go once the likes of Ross begin to fail.

I've often reffered to a dam as a good way to explain the failure of the ice sheets.

The noughties saw the cracks become visible and we are now seeing the first jets of water spurting from those cracks.

How long before we see structural failure?

Link to comment
Share on other sites

Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

And I remember you pushing a paper from Serezze and his death spiral at every available opportunity. At least he had the decency to retract and apologise for his excited haste....

By all means criticise scientific papers, but criticise folk for having faith in peer reviewed papers???? Are you seriously suggesting that the only peer reviewed stuff which should be listened to and noted are ones you agree with, or ones which show what you want them to show?

I'm pretty sure the basis for all science is one of progression, a paper published this year about any given subject may well be super ceded next year if more information/evidence is available to study. No science is set in stone, least of all, climate science. Criticising that process (as you do above) either reveals you do not appreciate how science progresses or demonstrates a desire to bicker just for the sake of it - neither one of those options does your stance or argument in favour of AGW any favours.

I think if you look at the ice loss data as a 360 degree ,year over year plot, you will see a familiar shape emerging and it is most visible if you use the volume plots?

07' dropped the min by 20 odd percent lower than ever measured. Last summer by 18% more than ever measured. Greenland has a melt rate doubling every 4 years the Arctic seems set on losing a 1/5 of that remaining every 5 years. How long before the Arctic slips below 1 million on it's current trajectory and how long before we start to see just how fast Greenland alone will pass the worse case scenario for sea level rise max for 2100?

As for sceptically approaching science papers? Is that not what we do? Some fail our own measures due to either the weight of peer reviewed papers showing the opposite that have passed our sceptical gaze and others because they have been superseded by events on the ground.

The paper I refered to was of the latter kind with data coming from Greenland that summer showing that no such peak had been reached.

EDIT: And yes I do find it pleasing to have my understanding proven right as time passes and confirmation via the data appears. I do not find the actuality of the changes we witness pleasing in the least though.

Edited by Gray-Wolf
Link to comment
Share on other sites

Posted
  • Location: Cheddar Valley, 20mtrs asl
  • Weather Preferences: Snow and lots of it or warm and sunny, no mediocre dross
  • Location: Cheddar Valley, 20mtrs asl

You've clearly missed your way in life Ian, although I imagine it's not too late to follow your obvious calling - and no, I'm not being sarcastic. For a mere mortal like me who hasn't the time to devote to endless hours of reading, I have to rely on the results on the scientists. If they plot the history of Greenland melt and can detect a cyclical element, I'm happy to accept their word on it. What I'm less happy to do is accept studies based on incredibly short time spans, for me that is the way to see what you want to see. Places like Greenland have a glacial history eons long, studying that can only be done via proxy measurements, how accurate those proxies are, how they are interpreted and then placed alongside modern measurements, leaves a large scope for inaccuracies to occur. I admire the resolute conviction of some of the claims made, that doesn't however mean I am convinced by them.

Given how little we actually know, the vast amount we don't know, coupled with the immeasurable amount of what we don't know, we don't know, I'm absolutely certain new study after new study will reveal a clearer picture. For now, I'm happy to accept everything is as clear as mud and see no point in latching on to every snippet of info as being the gospel truth. And that's where you and I divide into the chasm of opposing views, I'm happy to say we don't know, you're absolutely certain we do.

Link to comment
Share on other sites

Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

It's a good job we don't allow ourselves the luxury of time when watching volcanoes? Another dynamic system that we know little about but enough to know the danger signs?

Seeing as NASA tells us that our forcing is twenty times faster than any 'natural' forcing how can we use proxy studies to see the time-line of Greenland's collapse? We can tell that Greenland is very quick to react to Temperature forcings in the past but what occurs when those forcings are way faster than previously experienced?

The collapse of ice sheets would appear to need the wisdom of structural engineers to fully understand how the ice sheet will react in collapse (which is why I use the 'Dam' as my analogy)

What we are now beginning to see is the start of the draining of the interior ice sheet (since mass loss overtook mass gain) and this will have both temperature driven changes and gravity driven changes to the ice as it begins it's interior structural failure.

The changes due to gravity do not depend on Temperature but on the structure of the ice below (from crystal size to massive ice blocks) and , like a game of Jenga, the loss of one small section will lead to total and rapid collapse even if the signs are not visible from the surface.

We know a lot of the past melt is held in the snow cover but now this snow cover is in melt and so we can expect releases far greater than pure snow would give. Some of this is simple run off but the majority migrates through the ice mass eroding passages, and eventually caves, below the ice. These changes are not visible but from studying drain glaciers we can assume that the process is just as established in the ice sheet behind.

We know ice failure seismic activity is on the increase across Greenland.

How long before we start to see surface changes in the ice surface highlighting failures below? Once failure occurs the surface area of the ice exposed to running water explodes meaning the detritus from the collapse will melt out far faster than the 'solid ice' would leaving further caverns for the ice to collapse into.

This process will not be a 'year by year' spectacle but a month by month accelerating event.

As I've said above I believe that all the past can show us is that Greenland can and does melt with certain Temp/GHG levels imposed. Though temp has been pegged (dimming and the niceties of climate inertia?) GHG levels lead us to a time when Greenland carried at least 1/3 less ice. I am in no doubt that over the lifetime of the GHG's we would see such a reduction in ice mass but , sadly, the story has not ended has it? With natures contributions of the dormant Carbon cycle and our continuation to break emissions record (with Fracking now promising to continue this for another 60 years min) we do not know how much of Greenland we will free from ice.

Of course Greenland is small Beer when compared to Antarctica and what we see across Greenland we will see occur there also. current GHG's promise an ice Free West Antarctic during the lifetime of those GHG's and the loss of that ice entails the loss of Ross embayment (holding back the ice from the East Antarctic Ice sheets....as we have seen in past epochs) but again we do not know what the final figure of GHG's would be even if we ceased their production today?

Any system that double output every 4 years will entail massive losses over a very small time frame. Sadly , ice being ice, this figure will not remain stable and the time period for doubling will shorten over time as ever more ice collapses to reveal more surface and elevations drop bring more ice into the melt zones.

Link to comment
Share on other sites

Posted
  • Location: Swallownest, Sheffield 83m ASL
  • Location: Swallownest, Sheffield 83m ASL

Seeing as NASA tells us that our forcing is twenty times faster than any 'natural' forcing how can we use proxy studies to see the time-line of Greenland's collapse? We can tell that Greenland is very quick to react to Temperature forcings in the past but what occurs when those forcings are way faster than previously experienced?

The thing is though Ian, NASA told us that we knew how the sun worked and went on to forecast the highest activity ever recorded for this current cycle. This on it's own set alarm bells ringing throughout the climate change community when it failed to materialise and is in fact the complete opposite. Not exactly the confidence builder the community needs. I am even more cautious when it comes to NASA claiming something now. I should imagine there are a great number of others asking why we should trust their findings in one form or another..

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • UK Storm and Severe Convective Forecast

    UK Severe Convective & Storm Forecast - Issued 2024-03-29 07:13:16 Valid: 29/03/2024 0600 - 30/03/2024 0600 THUNDERSTORM WATCH - FRI 29 MARCH 2024 Click here for the full forecast

    Nick F
    Nick F
    Latest weather updates from Netweather

    Difficult travel conditions as the Easter break begins

    Low Nelson is throwing wind and rain at the UK before it impacts mainland Spain at Easter. Wild condtions in the English Channel, and more rain and lightning here on Thursday. Read the full update here

    Netweather forecasts
    Netweather forecasts
    Latest weather updates from Netweather

    UK Storm and Severe Convective Forecast

    UK Severe Convective & Storm Forecast - Issued 2024-03-28 09:16:06 Valid: 28/03/2024 0800 - 29/03/2024 0600 SEVERE THUNDERSTORM WATCH - THURS 28 MARCH 2024 Click here for the full forecast

    Nick F
    Nick F
    Latest weather updates from Netweather
×
×
  • Create New...