Lake Erie finally frozen over

[OKIsItJustMe]

http://www.tillsonburgnews.com/News/381608.html

Lake Erie finally frozen over

Ice fishing takes off

By Jeff Helsdon STAFF WRITER
Wednesday March 05, 2008

It’s nearly the end of February and Lake Erie is only now completely frozen over.

According to Canadian Ice Service data, the lake froze over last week. In an average winter, Lake Erie is ice covered by the first week of February.

"In the last 10 years since global warming has kicked in, it’s been a little later, if at all," said Lionel Hache, senior ice forecaster with the Canadian Ice Service.

Ice in that typical winter would have covered the lake for the entire month of February and then started to melt in March. Hache said temperatures are forecast to be cool the next couple of weeks so the ice will stick around. As it isn’t as thick as normal, Hache said there would be a rapid decline in lake ice by mid-March.

...

Yup, global cooling's taking hold!

[rurallib]

1. Didn't Lake Erie used to be a fire hazard?

Some sarcasm there. But seriously I have heard that Lake Superior has lost something like 9 inches of water due to not freezing over any more. And 9 inches on Lake Superior is a huge amount of water.

[madrchsod]

3. it was a river in cleveland

i can`t spell it!

[OKIsItJustMe]

4. Cuyahoga

http://www.lyricsdepot.com/randy-newman/burn-on.html

Burn On Lyrics
Artist: Randy Newman
Album: Sail Away

There's a red moon rising
On the Cuyahoga River
Rolling into Cleveland to the lake

...

Cleveland city of light city of magic
Cleveland city of light you're calling me
Cleveland, even now I can remember
'Cause the Cuyahoga River
Goes smokin' through my dreams

Burn on, big river, burn on
Burn on, big river, burn on
Now the Lord can make you tumble
And the Lord can make you turn
And the Lord can make you overflow
But the Lord can't make you burn

Burn on, big river, burn on
Burn on, big river, burn on

http://query.nytimes.com/gst/fullpage.html?res=950DE3D71531F936A15755C0A96F948260

River Not Yet Clean, but It's Fireproof

By DORON P. LEVIN, SPECIAL TO THE NEW YORK TIMES
Published: June 25, 1989

LEAD: The good news about the Cuyahoga River, which became a symbol of urban pollution when it caught fire two decades ago, is that the river is no longer flammable.

The good news about the Cuyahoga River, which became a symbol of urban pollution when it caught fire two decades ago, is that the river is no longer flammable.

The bad news, at least for officials who hoped to prove today that the river has shed the reputation that made it the butt of countless jokes, is that three weeks of steady rain turned its waters a murky brown.

The color of the water, and the rubbish floating past, was somewhat discouraging for the environmental officials and city boosters as they cruised along the Cuyahoga today to mark the 20th anniversary of the blaze. On that day, June 22, 1969, floating oil and debris were ignited by molten slag from a steel mill.

...

[gristy]

2. Yay!!!!!!

Global warming is history! Kidding!

[pbca]

5. According to the Premiere of British Columbia

Climate is moving north at the rate of 100 km per 10 years. So, if you want a general idea of the effects (minus the inevitable flooding of coastal regions) look south of you and count

122 miles (approx) - is what you'll have in 20 years
244 miles in 40 years
etc.,

This is what's happening now, not what is coming and the Coastal flooding is pretty much unpreventable now - Houston, New Orleans and the WTC monument will be underwater in 50 or so years - no matter what we do today (except build dikes I suppose)

[kristopher]

7. Perhaps you should check your information

I could be wrong (I'm not though) but the significance of 50 years from now related to sea level rise refers to the predicted level of CO2 at that time, not the actual effects of the rise in co2 concentration.
The sea level rise we've seen to date is due to thermal expansion and isn't a significant risk to most coastal areas. What happens in 50 years is that, *if we keep on our present course*, we will have put enough co2 into the air to ensure the melting of the Greenland Ice Cap. That will not happen immediately. It will take about 800-1000 years and will result in an increase of about 23 ft in sea level. y
So the moral of the story is that action is required now to prevent a catastrophe in the far future.

But that isn't the real worry - the flooding just makes a nice dramatic statement that is easy to visualize. The near term climate changes are going to wreak some real havoc with the way society is structured re food, biodiversity and natural resources.
In the realm of documented bad shit happening now, I would direct your anxiety to the topic of ocean acidification.

[pbca]

8. Ocean acidification and overfishing

which may cause mass extinction of sea life in the very short term but, low lying areas in other parts of the world - Egypt and Greece for example are already experiencing unprecedented flooding. The northern ice cap is melting much faster than originally predicted. Here (in Canada) there is a news story 3 or 4 times a year when they announce that it's going 'even faster' than before. We're expecting the northern channel to be an active shipping route within a decade.

[kristopher]

10. Yes, but the arctic ice is already in the water. Doesn't raise sea level when it melts.

[pbca]

11. It's not just the ice in the water

It's glaciers disappearing so fast you can watch them without time lapse - plus the land based permafrost is melting and running into the sea.

[kristopher]

12. There is no significant sea level rise expected near term.

[OKIsItJustMe]

14. (depending on how you define "significant" and "near term")

[kristopher]

15. Suppose you define them.

The principle worry about sea level rise is associated with Greenland.
Any fears of catastrophic sea level rise before that are the result of faulty mental models of the situation we face.

The amount of rise from further thermal expansion coupled with melting glaciers is extremely minor relative to the 7 meters expected from greenland. The effects of Greenland are clearly being described in the initiating post. The original claim: "This is what's happening now, not what is coming and the Coastal flooding is pretty much unpreventable now - Houston, New Orleans and the WTC monument will be underwater in 50 or so years - no matter what we do today (except build dikes I suppose)"

[OKIsItJustMe]

16. Well... let's be old fashioned

Significant

1: having meaning; especially : suggestive <a significant glance>
2 a: having or likely to have influence or effect : important <a significant piece of legislation>; also : of a noticeably or measurably large amount <a significant number of layoffs> <producing significant profits> b: probably caused by something other than mere chance <statistically significant correlation between vitamin deficiency and disease>

By definition, significant sea level rise has already happened. It's already having noticeable effects.
http://www.worldviewofglobalwarming.org/pages/rising-seas.html

"Near term" is another matter, it's relative. However, when talking about "climate change" I'd definitely call within the 21st century "near term."
http://pubs.giss.nasa.gov/abstracts/2007/Hansen.html

...

The nonlinearity of the ice sheet problem makes it impossible to accurately predict the sea level change on a specific date. However, as a physicist, I find it almost inconceivable that BAU climate change would not yield a sea level change of the order of meters on the century timescale. ...

[kristopher]

17. And this fits into the discussion how....

[OKIsItJustMe]

18. You asked for a definition of terms

I gave you definitions.

You suggested that sea level rise due to melting ice are not be expected to play a "significant" role in the "near term." I pointed you to a source that feels it will.

[kristopher]

19. You're being childish

The remarks that set of this subthread demonstrate a clear and common misunderstnading regarding climate change and rising sea level. The poster referred to US coastal cities being underwater. With the reference to fifty years, he demonstrates that he has inked cause (CO2 @ 500ppm) and effect (Greenland ice cap melting and SIGNIFICANT sea level rise) incorrectly and was unaware of the true nature of the problem.
I introduced thermal expansion which has been the basis of the relatively MINOR sea level rise we are seeing near term (within this century is as good a benchmark as any).

With all due respect to your link, it DOE NOT say that melting ice is expected to play a significant role in the near term. It is discussion the effects of thermal expansion, and it doesn't do a very good job of that frankly. The coastal areas they use as examples of climate change induced flooding are, in many cases, historically subject to the effects they are pointing to. Shorelines shift occurs for a large number of reasons. The coast near where I live (it's on your page) has shifted dramatically in the past 100 years. It has moved inland a couple of miles in many areas, it has extruded into the ocean in other areas, and it has formed barrier islands in yet others.
It is a complex set of dynamics at work that doesn't lend itself to oversimplification.

But the bottom line is that sea level rise due to melting ice isn't expected to play a significant role in coastal flooding over the near term.

[OKIsItJustMe]

20. Okay, you define the terms then

I don't expect to see much flooding in Manhattan (for example) attributable to glacial ice melt in the next few days or even few years.

"Near term" is a relative measure of time. "Near term" as compared to what? (6 millenia?)

According to Hansen:

...

However, Hansen et al (2007) show that the typical ∼6ky timescale for paleoclimate ice sheet disintegration reflects the half-width of the shortest of the weak orbital forcings that drive the climate change, not an inherent timescale of ice sheets for disintegration. Indeed, the paleoclimate record contains numerous examples of ice sheets yielding a sea level rise of several meters per century, with forcings smaller than that of the BAU scenario. The problem with the paleoclimate ice sheet models is that they do not generally contain the physics of ice streams, effects of surface melt descending through crevasses and lubricating basal flow, or realistic interactions with the ocean.

Rahmstorf (2007) has noted that if one uses the observed sea level rise of the past century to calibrate a linear projection of future sea level, BAU warming will lead to a sea level rise of the order of one meter in the present century. This is a useful observation, as it indicates that the sea level change would be substantial even without the nonlinear collapse of an ice sheet. However, this approach cannot be taken as a realistic way of projecting the likely sea level rise under BAU forcing. The linear approximation fits the past sea level change well for the past century only because the two terms contributing significantly to sea level rise were (1) thermal expansion of ocean water and (2) melting of alpine glaciers.

Under BAU forcing in the 21st century, the sea level rise surely will be dominated by a third term: (3) ice sheet disintegration. This third term was small until the past few years, but it is has at least doubled in the past decade and is now close to 1 mm/year, based on the gravity satellite measurements discussed above. As a quantitative example, let us say that the ice sheet contribution is 1 cm for the decade 2005–15 and that it doubles each decade until the West Antarctic ice sheet is largely depleted. That time constant yields a sea level rise of the order of 5 m this century. Of course I cannot prove that my choice of a ten-year doubling time for nonlinear response is accurate, but I am confident that it provides a far better estimate than a linear response for the ice sheet component of sea level rise under BAU forcing.

An important point is that the nonlinear response could easily run out of control, because of positive feedbacks and system inertias. Ocean warming and thus melting of ice shelves will continue after growth of the forcing stops, because the ocean response time is long and the temperature at depth is far from equilibrium for current forcing. Ice sheets also have inertia and are far from equilibrium: and as ice sheets disintegrate their surface moves lower, where it is warmer, subjecting the ice to additional melt. There is also inertia in energy systems: even if it is decided that changes must be made, it may require decades to replace infrastructure.

...

[kristopher]

21. From childish to petulant?

Near term was obviously being used in reference to the 800-1000 year time frame for greenland ice cap melting, not the time frame estimated for the Antarctic.

If you have an argument to make, make it, don't try to slough off an out of context, not to the point quote in place of a clear statement of your argument. What are you claiming this snippet supports?

You gave no source but I've tracked down the place you got it, who wrote it and the original article being cited.

I eagerly await your reply.

PS I much prefer an adult and factually oriented dialogue to "gotcha" games, but if you want to play that way...

[OKIsItJustMe]

22. Oh please...

I'd already given you the source earlier in the thread.

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=137277&mesg_id=137456

Go back and read your own post. "There is no significant sea level rise expected near term."

[kristopher]

23. And there isn't.

What you presented was a recommendation to bring dialogue on this specific topic to the forefront. It hardly provides the basis for a claim of near term sea level rise that's driven by melting ice. If you look elsewhere at my posts you'll see advocacy for increased spending on sensing systems capable of establishing the real time effects of global warming on deep sea currents. Without that, we are left with the modeling that we have now; which predict no significant sea level rise in the near term.

You pointed to a non-authoritative website that perpetuates the legend you are trying to defend by using crap that has no basis if fact as evidence. For example, shorelines are simply not static, they tend to move miles within decades in the normal source of events. Especially shorelines that are part of sand flats extending out to sea. They pointed to decline in horsehoe crab eggs as a food source for various species of migrating shorebirds, then say their foraging area is going to be reduced. The reader is left (deliberately I believe) with the impression that climate change and rising sea level are to blame for the lack of horseshoe crab eggs. In fact, climate change has nothing to do with it. The problem was generated by discovery that an organ within the horseshoe crab (liver I think) was valuable for production of some drug by big pharma. They have since found a replacement but the horseshoe crab population has yet to re cover.


There is no significant sea level rise expected near term.

Yes it MIGHT happen. Certainly there are outlying models that predict faster melting, however, that isn't the expectation. If you have real evidence that contradicts this I'd love to hear it.

[OKIsItJustMe]

24. Hmmm...

The non-authoritative web site is the NASA Goddard Institute for Space Studies. According to their web site:

...

Current research, under the direction of Dr. James Hansen, emphasizes a broad study of Global Change, which is an interdisciplinary initiative addressing natural and man-made changes in our environment that occur on various time scales (from one-time forcings such as volcanic explosions, to seasonal/annual effects such as El Niño, and on up to the millennia of ice ages) and affect the habitability of our planet. Program areas at GISS may be roughly divided into the categories of climate forcings, climate impacts, model development, Earth observations, planetary atmospheres, paleoclimate, radiation, atmospheric chemistry, and astrophysics and other disciplines. However, due to the interconnections between these topics, most GISS personnel are engaged in research in several of these areas.

A key objective of GISS research is prediction of atmospheric and climate changes in the 21st century. The research combines analysis of comprehensive global datasets, derived mainly from spacecraft observations, with global models of atmospheric, land surface, and oceanic processes. Study of past climate change on Earth and of other planetary atmospheres serves as a useful tool in assessing our general understanding of the atmosphere and its evolution.

The perspective provided by space observations is crucial for monitoring global change and for providing data needed to develop an understanding of the Earth system. As the principal NASA center for Earth observations, Goddard Space Flight Center plays a leading role in global change research. Global change studies at GISS are coordinated with research at other groups within the Earth Sciences Division, including the Laboratory for Atmospheres, Laboratory for Hydrospheric and Biospheric Sciences, and Earth Observing System science office.
...

The author of the paper I quoted is the same http://www.giss.nasa.gov/staff/jhansen.html">James Hansen.

The thrust of his paper is made quite clear in the abstract:
http://pubs.giss.nasa.gov/docs/2007/2007_Hansen.pdf

Abstract
I suggest that a ‘scientific reticence’ is inhibiting the communication of a threat of a potentially large sea level rise. Delay is dangerous because of system inertias that could create a situation with future sea level changes out of our control. I argue for calling together a panel of scientific leaders to hear evidence and issue a prompt plain-written report on current understanding of the sea level change issue.

The references in his paper are quite extensive.

[kristopher]

25. Nothing like a straw man, eh?

I didn't say Hanson's paper was not authoritative - that was the other link you had on the same page.

What I did say was that Hanson's paper isn't substantiation for the claim of near term sea level rise from land locked ice. It points to valid concerns about the expectations we have arrived at and advocates strongly for bolder dialogue specifically on that topic, but that is all it does.

I share his concerns to a degree. However my more immediate worry is the methane hydrate frozen at the bottom of the ocean. We have very limited knowledge regarding the conditions that are going to allow this gas to be released on a large scale. We do know, however, that there is more than enough of it that if it is released, we are really and truly fucked. As a species we would almost certainly survive even rapic sea level rise. It is questionable, however whether or not our species would survive the release of the methane deposits.

Even with that concern, I do not make a habit of broadcasting it as something to be expected by 2050 because the bulk of the work out there doesn't support such a claim. Just as the bulk of the work out there doesn't support the claim of significant sea level rise during this century. The strongest statement that can be made at this time is that by 2050, under a business as usual approach, we will commit to melting the Greenland Ice Cap and it's 7 meters of sea level rise. What is almost always left unarticulated is the time frame of 800-100 years that goes with that claim.

Both of these issues will become clearer as we continue to gather and analyze the data. Hopefully we will soon have the proper tools for the job.

By citing Hanson in the manner you are, you are confusing the process of science with the product of science.

[OKIsItJustMe]

26. Yes, straw men are easy opponents

What drew me into this discussion was your one-liner:
There is no significant sea level rise expected near term.

My (one-line) response (which I stand by) was:
(depending on how you define "significant" and "near term")

The third question I should have asked (but did not) was "who does not expect it?"


According to Working Group I of the IPCC, "significant" sea-level rise is already taking place, and appears to be accelerating. Ice melt is responsible for a significant portion of it.
http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter5.pdf

...

• Global mean sea level has been rising. From 1961 to 2003, the average rate of sea level rise was 1.8 ± 0.5 mm yr^–1. For the 20th century, the average rate was 1.7 ± 0.5 mm yr^–1, consistent with the TAR estimate of 1 to 2 mm yr^–1. There is high confidence that the rate of sea level rise has increased between the mid-19th and the mid-20th centuries. Sea level change is highly non-uniform spatially, and in some regions, rates are up to several times the global mean rise, while in other regions sea level is falling. There is evidence for an increase in the occurrence of extreme high water worldwide related to storm surges, and variations in extremes during this period are related to the rise in mean sea level and variations in regional climate.


• The rise in global mean sea level is accompanied by considerable decadal variability. For the period 1993 to 2003, the rate of sea level rise is estimated from observations with satellite altimetry as 3.1 ± 0.7 mm yr^–1, significantly higher than the average rate. The tide gauge record indicates that similar large rates have occurred in previous 10-year periods since 1950. It is unknown whether the higher rate in 1993 to 2003 is due to decadal variability or an increase in the longer-term trend.


• There are uncertainties in the estimates of the contributions to sea level change but understanding has significantly improved for recent periods. For the period 1961 to 2003, the average contribution of thermal expansion to sea level rise was 0.4 ± 0.1 mm yr^–1. As reported in the TAR, it is likely that the sum of all known contributions for this period is smaller than the observed sea level rise, and therefore it is not possible to satisfactorily account for the processes causing sea level rise. However, for the period 1993 to 2003, for which the observing system is much better, the contributions from thermal expansion (1.6 ± 0.5 mm yr^–1) and loss of mass from glaciers, ice caps and the Greenland and Antarctic Ice Sheets together give 2.8 ± 0.7 mm yr^–1. For the latter period, the climate contributions constitute the main factors in the sea level budget, which is closed to within known errors.

...

Frequently Asked Question 5.1

Is Sea Level Rising?

Yes, there is strong evidence that global sea level gradually rose in the 20th century and is currently rising at an increased rate, after a period of little change between AD 0 and AD 1900. Sea level is projected to rise at an even greater rate in this century. The two major causes of global sea level rise are thermal expansion of the oceans (water expands as it warms) and the loss of land-based ice due to increased melting.

...

The IPCC predicts that significant sea level rise will continue and that ice melt will accelerate:
http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter10.pdf

...

Sea level is projected to rise between the present (1980–1999) and the end of this century (2090–2099) under the SRES B1 scenario by 0.18 to 0.38 m, B2 by 0.20 to 0.43 m, A1B by 0.21 to 0.48 m, A1T by 0.20 to 0.45 m, A2 by 0.23 to 0.51 m, and A1FI by 0.26 to 0.59 m. These are 5 to 95% ranges based on the spread of AOGCM results, not including uncertainty in carbon cycle feedbacks. For each scenario, the midpoint of the range is within 10% of the TAR model average for 2090-2099. The ranges are narrower than in the TAR mainly because of improved information about some uncertainties in the projected contributions. In all scenarios, the average rate of rise during the 21st century very likely exceeds the 1961 to 2003 average rate (1.8 ± 0.5 mm yr^–1). During 2090 to 2099 under A1B, the central estimate of the rate of rise is 3.8 mm yr^–1. For an average model, the scenario spread in sea level rise is only 0.02 m by the middle of the century, and by the end of the century it is 0.15 m.

...

Glaciers and ice caps are sensitive to changes in temperature and precipitation. Observations point to a reduction in volume over the last 20 years (see Section 4.5.2), with a rate during 1993 to 2003 corresponding to 0.77 ± 0.22 mm yr^–1 sea level equivalent, with a larger mean central estimate than that for 1961 to 1998 (corresponding to 0.50 ± 0.18 mm yr^–1 sea level equivalent). Rapid changes are therefore already underway and enhanced by positive feedbacks associated with the surface energy balance of shrinking glaciers and newly exposed land surface in periglacial areas. Acceleration of glacier loss over the next few decades is likely (see Section 10.6.3). Based on simulations of 11 glaciers in various regions, a volume loss of 60% of these glaciers is projected by the year 2050 (Schneeberger et al., 2003). Glaciated areas in the Americas are also affected. A comparative study including seven GCM simulations at 2 × atmospheric CO₂ conditions inferred that many glaciers may disappear completely due to an increase in the equilibrium line altitude (Bradley et al., 2004). The disappearance of these ice bodies is much faster than a potential re-glaciation several centuries hence, and may in some areas be irreversible.

...

As alarming as the IPCC report should be, Hansen seems to believe it is far too conservative.

...

The IPCC (2007) midrange projection for sea level rise this century is 20–43 cm (8–17 inches) and its full range is 18–59 cm (7–23 inches). The IPCC notes that they are unable to evaluate possible dynamical responses of the ice sheets, and thus do not include any possible ‘rapid dynamical changes in ice flow’. Yet the provision of such specific numbers for sea level rise encourages a predictable public response that the projected sea level change is moderate, and smaller than in IPCC (2001). Indeed, there have been numerous media reports of ‘reduced’ sea level rise predictions, and commentators have denigrated suggestions that business-as-usual greenhouse gas emissions may cause a sea level rise of the order of meters.

...

I feel you do Hansen a disservice, by suggesting that his paper is merely a call for dialog. I believe he is saying (in only slightly couched terms) that scientists are not making their true expectations known regarding sea level rise:

...

I suggest that ‘scientific reticence’, in some cases, hinders communication with the public about dangers of global warming. If I am right, it is important that policy-makers recognize the potential influence of this phenomenon.

Scientific reticence may be a consequence of the scientific method. Success in science depends on objective skepticism. Caution, if not reticence, has its merits. However, in a case such as ice sheet instability and sea level rise, there is a danger in excessive caution. We may rue reticence, if it serves to lock in future disasters.

...

... The lawyer then, with aplomb, requested that I identify glaciologists who agreed publicly with my assertion that the sea level was likely to rise more than one meter this century if greenhouse gas emissions followed an IPCC business-as-usual (BAU) scenario: ‘Name one!’

I could not, instantly. I was dismayed, because, in conversation and e-mail exchange with relevant scientists I sensed a deep concern about likely consequences of BAU global warming for ice sheet stability. What would be the legal standing of such a lame response as ‘scientific reticence’? Why would scientists be reticent to express concerns about something so important?

...

I believe there is a pressure on scientists to be conservative. Papers are accepted for publication more readily if they do not push too far and are larded with caveats. Caveats are essential to science, being born in skepticism, which is essential to the process of investigation and verification. But there is a question of degree. A tendency for ‘gradualism’ as new evidence comes to light may be illsuited for communication, when an issue with a short time fuse is concerned.

...

Hansen does not claim that the Statue of Liberty will bybe up to her nose in glacial melt tomorrow. However, I feel it's fair to say that at the very least, he expects significant sea-level rise, attributable to the loss of land ice, in the "near term."

I also believe that it is fair to infer that he believes others share his beliefs, but (for whatever reason) feel compelled not to publicly state so.

[kristopher]

27. I see

The idea of adding original perspective is a very good one, it helps bring clarity to the discussion. It would be better though, to include just little more information.

"This is what's happening now, not what is coming and the Coastal flooding is pretty much unpreventable now - Houston, New Orleans and the WTC monument will be underwater in 50 or so years - no matter what we do today (except build dikes I suppose)"


This is the comment I was addressing with the remark you responded to. Either you read the entire thread and have, for some reason known only to yourself, decided to deliberately mischaracterize my remark, or you shot from the hip without knowing the context and now refuse to address your failure.

The scope of the terms /significant/ and /near term/ are clearly defined by the context; starting with the above quoted section.

The statement not only is untrue, it is a hugely untrue.

I was not addressing seal level rise on the order of 2mm/year or 3mm/year; I was addressing the claim that sea level rise on the order of 294mm/year (7m over 42 year) was currently taking place.

The claim made equates to the entire sea level rise predicted this century taking place each and every year between now and 2050.

It's unfortunate you choose to pursue so vigorously such an obvious straw man.

[OKIsItJustMe]

28. Repeating myself again

...

I was not addressing seal level rise on the order of 2mm/year or 3mm/year; I was addressing the claim that sea level rise on the order of 294mm/year (7m over 42 year) was currently taking place.

...

Once again, from Hansen's paper:

... Indeed, the paleoclimate record contains numerous examples of ice sheets yielding a sea level rise of several meters per century, with forcings smaller than that of the BAU scenario. ...

The nonlinearity of the ice sheet problem makes it impossible to accurately predict the sea level change on a specific date. However, as a physicist, I find it almost inconceivable that BAU climate change would not yield a sea level change of the order of meters on the century timescale. The threat of a large sea level change is a principal element in our argument (Hansen et al 2006a, 2006b, 2007) that the global community must aim to keep additional global warming less than 1°C above the 2000 temperature, and even 1°C may be too great. In turn, this implies a CO₂ limit of about 450 ppm, or less. Such scenarios are dramatically different than BAU, requiring almost immediate changes to get on a fundamentally different energy and greenhouse gas emissions path.

...

My point is that the scenario is not as far fetched as you make it out to be.

[kristopher]

32. You are misreading Hanson

He is initiating a discussion calling for a closer look at low probability models. That IS NOT the same as the prediction that was cited as fact. You absolutely insist on detaching my comments from their origin and trying to construct a straw man. He is discussing several different prospects and calling for a reexamination of the data and the public face of the scientific dialogue. Yet here you are trotting them out one after another as if they are conclusions that have already been arrived at. Your sensationalistic behavior is precisely why there is a reluctance on the part of these scientists to bring these discussions more into the forefront of public discussion. If never fails that the overall picture is inappropriately slanted to the most dramatic scenario available.

Tell you what, you show me where Hanson or any other authority has made a statement that specifically supports this, complete with degree of certainty; and I'll concede the point. "This is what's happening now, not what is coming and the Coastal flooding is pretty much unpreventable now - Houston, New Orleans and the WTC monument will be underwater in 50 or so years - no matter what we do today (except build dikes I suppose)"

keywords: is (emphasis on present progressive tense) happening now; unpreventable; will be (emphasis on future passive tense) underwater in 50 years; no matter what

Lacking that, you are arguing a straw man.

[OKIsItJustMe]

33. Only time will tell

50 years from now, we may look back and say, "That is what was happening then, not what was coming and the Coastal flooding was pretty much unpreventable then - Houston, New Orleans and the WTC monument were doomed to be underwater by now."

Perhaps our friend overstretched in his certainty. However, perhaps you have as well. At this point, there's a lot of guesswork going on.

Regardless, when it comes to Hansen, I believe you are the one who is misreading him. He is (in essence) asking other scientists to plainly tell the truth to the public.

...

There is, in my opinion, a huge gap between what is understood about human-made global warming and its consequences, and what is known by the people who most need to know, the public and policy makers. The IPCC is doing a commendable job, but we need something more. Given the reticence that the IPCC necessarily exhibits, there need to be supplementary mechanisms. The onus, it seems to me, falls on us scientists as a community.

...

[OKIsItJustMe]

29. Press Release - Rock studies help crack questions of glacier thinning in West Antarctica

http://www.antarctica.ac.uk/press/press_releases/press_release.php?id=348

Press Release - Rock studies help crack questions of glacier thinning in West Antarctica

Issue date: 28 Feb 2008
Number: 05/08

...

Initial results show that Pine Island Glacier has ‘thinned’ by around 4 centimetres per year over the past 5,000 years, while Smith and Pope Glaciers thinned by just over 2 cm per year during the past 14,500 years. These rates are more than 20 times slower than recent changes: satellite, airborne and ground based observations made since the 1990s show that Pine Island Glacier has thinned by around 1.6 metres per year in recent years.

...

The Amundsen Sea Embayment (ASE) lies on the side of the West Antarctic Ice Sheet (WAIS). It is an area that has always caused glaciologists concern, because here the bedrock beneath the ice is a long way below sea-level and the ice is only kept in place because it is thick enough to rest on the bed. Thinning of the ice around the coast could lead to glacier acceleration and further thinning of the ice sheet. Essentially, the ice sheet may be unstable, and the recent pattern of thinning could be a precursor to wholesale loss of the ASE ice sheet (implying a sea-level rise of around 1.5 m).

Complete collapse of the WAIS would result in a rise of about 5 m in global sea level. Most scientists working in the area think that complete collapse within the next few hundred years is unlikely, but even loss of one sector of the ice sheet would imply that projections of sea-level rise are at present too low.

...

Pine Island Glacier is of great interest to scientists worldwide as it has been thinning at a rate of more than 1 m/year and its flow rate has accelerated over the past 15 years. The location at which the glacier starts to float on the sea also retreated at a rate of more than 1 km/year during part of this period.

...

[OKIsItJustMe]

30. Antarctic glaciers surge to ocean

http://news.bbc.co.uk/1/hi/sci/tech/7261171.stm

Last Updated: Sunday, 24 February 2008, 00:24 GMT

Antarctic glaciers surge to ocean

By Martin Redfern
Rothera Research Station, Antarctica

UK scientists working in Antarctica have found some of the clearest evidence yet of instabilities in the ice of part of West Antarctica.

...

Throughout the 1990s, according to satellite measurements, the glacier was accelerating by around 1% a year. Julian Scott's sensational finding this season is that it now seems to have accelerated by 7% in a single season, sending more and more ice into the ocean.

"The measurements from last season seem to show an incredible acceleration, a rate of up to 7%. That is far greater than the accelerations they were getting excited about in the 1990s."

...

David Vaughan believes that the risk of a major collapse of this section of the West Antarctic ice sheet should be taken seriously.

"There has been the expectation that this could be a vulnerable area," he said.

...

[OKIsItJustMe]

31. IPCC WG1 Chapter 10 -

http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter10.pdf

...

Box 10.1: Future Abrupt Climate Change, ‘Climate Surprises’, and Irreversible Changes

...

Greenland and West Antarctic Ice Sheets:

Satellite and in situ measurement networks have demonstrated increasing melting and accelerated ice flow around the periphery of the Greenland Ice Sheet (GIS) over the past 25 years (see Section 4.6.2). The few simulations of long-term ice sheet simulations suggest that the GIS will significantly decrease in volume and area over the coming centuries if a warmer climate is maintained (Gregory et al., 2004a; Huybrechts et al., 2004; Ridley et al., 2005). A threshold of annual mean warming of 1.9°C to 4.6°C in Greenland has been estimated for elimination of the GIS (Gregory and Huybrechts, 2006; see section 10.7.3.3), a process which would take many centuries to complete. Even if temperatures were to decrease later, the reduction of the GIS to a much smaller extent might be irreversible, because the climate of an ice-free Greenland could be too warm for accumulation; however, this result is model dependent (see Section 10.7.3.3). The positive feedbacks involved here are that once the ice sheet gets thinner, temperatures in the accumulation region are higher, increasing the melting and causing more precipitation to fall as rain rather than snow; that the lower albedo of the exposed ice-free land causes a local climatic warming; and that surface melt water might accelerate ice flow (see Section 10.6.4.2).

A collapse of the West Antarctic Ice Sheet (WAIS) has been discussed as a potential response to global warming for many years (Bindschadler, 1998; Oppenheimer, 1998; Vaughan, 2007). A complete collapse would cause a global sea level rise of about 5 m. The observed acceleration of ice streams in the Amundsen Sea sector of the WAIS, the rapidity of propagation of this signal upstream and the acceleration of glaciers that fed the Larsen B Ice Shelf after its collapse have renewed these concerns (see Section 10.6.4.2). It is possible that the presence of ice shelves tends to stabilise the ice sheet, at least regionally. Therefore, a weakening or collapse of ice shelves, caused by melting on the surface or by melting at the bottom by a warmer ocean, might contribute to a potential destabilisation of the WAIS, which could proceed through the positive feedback of grounding-line retreat. Present understanding is insufficient for prediction of the possible speed or extent of such a collapse (see Box 4.1 and Section 10.7.3.4).

...

[kristopher]

34. ALL of your references highlight the temporal uncertainty that I've been arguing

YOU have been DEFENDING the statement expressing certainty.

Again: you show me where Hanson or any other authority has made a statement that specifically supports this, complete with degree of certainty; and I'll concede the point. "This is what's happening now, not what is coming and the Coastal flooding is pretty much unpreventable now - Houston, New Orleans and the WTC monument will be underwater in 50 or so years - no matter what we do today (except build dikes I suppose)"

keywords: is (emphasis on present progressive tense) happening now; unpreventable; will be (emphasis on future passive tense) underwater in 50 years; no matter what

Lacking that, you are arguing STILL a straw man.

[OKIsItJustMe]

35. Actually, to me they highlight the unexpected speed with which things are happening

This seems to be an ongoing theme.

The IPCC report, as a consensus opinion, is relatively conservative. Time and time again (it seems) things are happening faster than predicted by the IPCC.

[Dr.Phool]

6. Let me know when hell freezes over.

It will mean the Browns finally won the Super Bowl.

[losthills]

9. Hell freezing over has been postponed

until further notice....

[kickysnana]

13. Bummer, we had to have all the ice houses of the lake by March 1st! n/t