http://en.wikipedia.org/wiki/Snowball_Earth
However, there is only one “very reliable” datum point identifying tropical tillites,[Evans (2000)] which makes statements of equatorial ice cover somewhat presumptuous. It is worth remembering that many sedimentary features traditionally associated with glaciers can also be formed by other means.[Arnaud, E.; Eyles, C.H. (2002)] Evidence includes:
* Dropstones (stones dropped into marine sediments), which can be caused by glaciers or by other causes.[Donovan, SK; Pickerill, RK 2007]
* Varves (annual sediment layers in periglacial lakes), which can form at higher temperatures.[Thunell, R.C.; Tappa, E., Anderson, D.M. 1995]
* Glacial striations (formed by embedded rocks scraped against bedrock): similar striations are from time to time formed by mudflows.[Jensen, PA; Wulff-pedersen, E. 1996]
* Diamictites (poorly sorted conglomerates). Originally described as glacial till, most were in fact formed by debris flows.[Eyles, N.; Januszczak, N. (2004)]
References:
D.A.D. Evans (2000). “Stratigraphic, geochronological, and paleomagnetic constraints upon the Neoproterozoic climatic paradox”. American Journal of Science 300 (5): 347 – 433.
Arnaud, E.; Eyles, C.H. (2002). “Glacial influence on Neoproterozoic sedimentation: the Smalfjord Formation, northern Norway”. Sedimentology 49 (4): 765-788. Retrieved on 2007-05-05.
Donovan, SK; Pickerill, RK (2007-04-27). “Dropstones: their origin and significance: a comment”. Palaeogeography, Palaeoclimatology, Palaeoecology 131 (1): 175-178. Retrieved on 2007-04-27
Thunell, R.C.; Tappa, E., Anderson, D.M. (1995-12-01). “Sediment fluxes and varve formation in Santa Barbara Basin, offshore California”. Geology 23 (12): 1083-1086. Retrieved on 2007-04-27.
Jensen, PA; Wulff-pedersen, E. (1996-03-01). “Glacial or non-glacial origin for the Bigganjargga tillite, Finnmark, Northern Norway”. Geological Magazine 133 (2): 137-145. Retrieved on 2007-04-27.
Eyles, N.; Januszczak, N. (2004). “‘Zipper-rift’: A tectonic model for Neoproterozoic glaciations during the breakup of Rodinia after 750 Ma”. Earth-Science Reviews 65 (1-2): 1-73. Retrieved on 2007-05-04.
Climate Audit 
87 Comments
I am repeatedly struck here and elsewhere by how, when presented with the problems in temperature measurement and measuring the CO2 GHE, the warmers retreat to fallacious arguments about glaciers and ice. There are several examples in this thread. For example,
As of today, increases in Antarctic sea ice are 2 to 3 times larger than decreases in Arctic sea ice (on an anomaly basis). The fact of the matter is the Antarctic is freezing much faster than the Arctic is melting. Ref Cryospehere today.
It is far from clear whether, by how much and from what cause the Greenland icesheet is melting. Quite simply no conclusions can be drawn about the effect of recent warming (and note the lag issue in the next point, which for Greenland will be many centuries, if not millenia).
Mountain glaciers respond to past warming/cooling with a lag of between a decade and several centuries. Melting (rather retreating, because glaciers always melt irrespective of warming or cooling) glaciers tell us almost nothing about the claimed recent global warming (the last 30 years).
Full disclosure: I filled up my car at a Shell station last week and got a 4c/litre discount.
295 Arthur Smith
Oh, come on, Arthur, not that “glaciers are melting” cr*p from you! You are certainly smart enough to know that while some glaciers are melting, others are growing, and many of the ones that are melting have been melting since long before 1850. If you hadn’t come out of Ithaca, I’d suspect you were kidding…
As far as aerosols are concerned, nobody brought those up until the AGW crowd realized they had a divergence problem to explain away — lots more CO2 but little warming.
The fact is that the Earth is never in equilibrium, so don’t hold your breath waiting for it. The land, the air, and the oceans are always trying to catch up with each other and the rest of the planet.
Do you have any references for this? From what I’ve read, glacier retreat is real and serious, having significant implications for water availability in a number of places around the world. Thanks.
Glacier retreat has no significant implications for water availability. Name one place where it does.
I have no idea why the IPCC claimed something so obviously false. Retreating glaciers increase water availability (i.e. river flow). If a glacier dissapears entirely, its equivalent to the glacier being stable i.e. no retreat or advance in terms of annual water availability.
I think this myth comes from people in temperate zones seeing that low river flow is in summer (the time when glacial melt makes its largest contribution to river flow) and assume this is the case everywhere. It’s not. In the Himalayan region (and right across the subtropics) commonly cited as where this problem will occur, high river flow is in the summer. If Himalayan glaciers were to dissapear, it would improve annual distribution of water availability by increasing low winter river flows and decreasing high summer river flows.
The Columbia River has 14 dams. I don’t see how changes in glacial melt will affect water availability. The only effect is a (possible) small seasonality change in net dam inflows.
#318 None of those 3 papers even mentions glaciers. Note I could only read the abstract for the second.
From the research I’ve read, initially, in some areas, glacier melt will result in increased water flow, but it will be larger than normal, increasing the potential for glacial lake outburst flooding and associated destruction from landslides, etc. Once the glaciers that feed rivers are gone, a significant decrease in water availability will follow, causing water shortages for populations and for crop irrigation. I don’t see why this is a difficult concept.
Some Canadian glaciers have retreated to their smallest size in 7,000 years. This is not based on models or projections, but is actual as evidenced by fossil forests uncovered as the glaciers retreat. Peru’s glaciers have decliend by 25% in the last few decades, and if the pace continues, they could be gone in a few decades. China’s glacier retreats could cause water shortage for millions.
Oh, Happy New Year! Must go and pop a cork. 🙂
#330 Susann says:
December 31st, 2007 at 11:22 pm
No, not all glaciers are currently retreating. A number of glaciers are presently advancing, even in North America. Yes, overall, glaciers have generally been retreating and losing mass balance for many years now…tens of thousands of years, fortunately. Inter-glacial periods tend to do so, and this one has been long enough to permit human civilization to develop and flower. Civilizations and biospheres tend to prosper and diversify in warm wet climatic conditions, and they tend to suffer and decline in cold dry climatic conditions. Don’t you think that you should be more worried about advancing glaciers instead of retreating glaciers? Would you like to take Steve M. and his family in as refugees from a new Laurentide ice sheet? If you are patient, you may see many of the North American and European glaciers advance again sometime around 2022 to 2034. Currently, some of the mass balance of the cryosphere has been shifting from the Northern Hemisphere to the Southern Hemisphere, meaning an undetermined amount of the cryosphere lost by Northern Hemisphere appears to have been gained by the Southern Hemisphere. Since you are so convinced the glacier mass balances are anomolous, would you care to cite two climate science authorities who have stated just how much mass balance the glaciers indiviually and collectively must have for the global climate to be in accepatable balance?
Re all this stuff about glaciers melting affecting river levels, I don’t think I really buy it. Surely most meltwater is from winter snows, not from glaciers which are longer term objects. Of course, glaciers receding would correlate, but not perfectly, with snow levels at the end of winter, and this then affects the amount of meltwater available for river flows in summer. But the actual amount of snowfall is IMHO the important thing.
And if the winter is warmer, and more of it falls as rain, well, someone said the Columbia River has umpteen dams, so store up the increased winter rainwater behind them. Therefore, is this really an issue?
Rich.
#341 & #344
Nothing new, just a reminder that advancing and retreating glaciers were instrumental in the creation of the Great Lakes, which include the largest freshwater lake in the world.
341, this is basically the same problem that the US SW has in the Colorado river basin. The 19th and 20th centuries have been unusually wet, and we’ve gotten used to all of this water that historically hasn’t been there. GW is just a footnote to the problem, and odds are there’s going to be a problem no matter what happens to temperature.
The real calamity is awaiting the SW in general, and California in particular, where population is increasing like there’s no tomorrow, and every reason to believe that water production will decline no matter what we do. What’s going to have to happen, is that people in those areas are going to have to give up their irrigated lawns, and start recycling gray water, and generally living like Israelis. Technology can help conserve water too, but people in those areas are going to have to get used to not having unlimited water on tap regardless of what happens to the climate.
BTW, water is one more reason why biofuels isn’t the panacea that many tout them as being. The drier future that we’re almost certainly looking at regardless of temperature will make that much agriculture impractical, and certainly at odds with other environmental concerns, such as fisheries.
Yes, and those suppliers of fresh water are in decline. It’s one study but is consistent with projections for global warming. Glaciers are retreating and freshwater supplies like the Great lakes are declining. May be part of a natural cycle, but may also be part of warming. Whatever the cause, it is a concern.
Susann, you mean it isn’t inconsistent with AGW. Though I’m sure you knew that. It isn’t inconsistent with a theory that invisible elephants are causing warming either. But more seriously, the glaciers would be melting regardless of the cause. Now the question is: what effect do we expect. It seems to me that if the glaciers melt, they will become water. That means that, at least temporarily, some rivers fed by glacial melt will receive more water. After that, presumably they won’t feed them anymore, unless they leave behind lakes, which isn’t that hard to imagine. The Great Lakes, as he said, were made by the “decline” of glaciers at the end of an ice age. The aren’t fed by glaciers presently. Ice doesn’t just die, you know, it becomes water, leaves behind puddles, lakes, rivers, etc.
Glaciers grow and retreat. The mass ice balance in the Columbia ice fields is declining slightly right now but it was increasing in the 1960s and 1970s and especially during the Little Ice Age.
Funny how the retreating glaciers reveal tree stumps which are Carbon-dated to the Mideaval Warm Period, the Roman Warm Period and the Holocene Climate Optimum. Trees grew a few hundred years ago where the glaciers are now?
The global warming community does its best to completely ignore history whenever it does not feed into the global warming scare.
re: #344 Susann, January 1st, 2008 at 9:38 am, who says
How do these denialists compare to those who don’t seem to believe that “climate change” and extinction are natural and have been the rule over the history of the earth?
re: #350 Susann, January 1st, 2008 at 10:30 am who says
It is a concern. But how best to deal with the various AGW issues, of whatever magnitude, is a major part of that concern. With China building a new coal fired power plant approximately every week, and other disadvantaged peoples wanting to enjoy some semblance of prosperity, at present there doesn’t seem to be any solution.
Retreating glaciers in Europe have recently uncovered a silver mine that was buried for 2000 years. 1000 year old vegetation was discovered under retreating glaciers in greenland. The bits of information suggest that the modern retreat of glaciers is not unprecedented.
Well, Arthur, the problem is that glaciers are influenced by precipitation as well. But you are right. A time lag means we should expect the effect of CO2 to continue for a while even without rises (you know, “commitment”) and we would expect this to contribute to glacial melt. But that matters much less if the contribution of CO2 is smaller than we presently believe. In fact, if solar activity is more important than we presently believe, it might start to get cooler, or at least slow down the warming. And all those coal plants in China could cause some global dimming, couldn’t they?
Actually, in the unlikely event of a sudden orbital shift, sudden increase in volcanic activity, etc. it might very suddenly get cold. But these aren’t very likely
Can we summarize the glacier controversy? I can’t tell who’s claiming what, beyond the fact that those who are reliably alarmist must be claiming that everything’s going to hell in a handbasket.
Larry #422 Unthreaded is not a place where substantive issues get resolved.
All, it’s not just about streamflow volumes and impacts on humans. Glacier-fed rivers are very different ecosystems from non-glacial fed rivers. Their unique character will change with deglaciation. This is not a value judgement, it’s a robust prediction.
(Unlike my prediction that the Gators would stomp Michigan. Good show, Wolverines.)
bender:
Think about this. during glaciation less water is available for use down stream as more is being held in the glaciers.
when the glaciers are gone all percipitation is goin down stream.
Wansbeck, yes, it was a big El Nino, really, though I’m not sure if it was that big.
TonyN, I’m afraid I wouldn’t know how to proceed.
Bender, Pat just thinks that the glacier stuff is getting a little old (and I would agree).
Susann, string theory isn’t the basis of a major policy, and serious string theorists (like Lubos, incidentally) don’t claim to have proof that they don’t have. Climate Science is another matter.
Pat, I agree with that. Actually, maybe this is a topic we can agree to drop?
Bender, your right about uncertainty, and how easy it is to revise to fit a hypothesis in the field. Hopefully more rigor will be demanded in the future.
533, ah sorry I see, I focused on “I have yet to see any evidence I find persuasive that water avalability from a river system of any size will be negatively impacted by glacial retreat.”
Anyway read: they might not be receding there as much as claimed. And that’s what glaciers do sometimes, thank goodness. Who wants them to grow?
WRL:
Thanks for the link I for one did read it. If Phill had taken the time to do that also he might have learned some thing.
Bender:
If the glaciers are growing there is less water down stream for the ranchers to use.
552, let’s get the semantics straight. You’re describing the snow pack, not the glacier. Snow packs build in the winter and melt in the summer where there are no glaciers. Glaciers, by definition, are the part that survive the summer, and are there all year, over the course of many years. Receding glaciers, in and of themselves, don’t impact the snow packs.
But I don’t want to be part of this discussion.
There is enough snow piled up in front of my house right now to replace as many glaciers as you wish. Please send trucks, planes and ships, take as much as you want, IT’S FREE!!!
I’m trying to follow the logic, and feel rather confused. I am wondering how many people (or what percent of the entire population) get their fresh water from melting glaciers? If the glaciers are still there, but stop melting, where would these people get their fresh water? Would it then be good or bad for the glaciers to stop melting and delivering fresh water downstream? Where do people get water when they aren’t downstream from a glacier?
So you’re saying that climate “patterns” would not change if it weren’t for AGW?
In my opinion JohnB UK has it right. There will be changes in flow and water availability regardless of what glaciers do. But I think we can all agree that if all glaciers were advancing that would be a bad thing for humanity. But I wouldn’t vote to “do anything” about it, because we’d just screw it up even more.
where is heraclitus when you need him
thanks! SteveM! Sorry bender! But please, I do try- very much so to have links attached to what I am talking about. If somebody doesn’t read them, they might not know what I am talking about.
Drinking water in the future is a huge concern, but it is mostly because of increasing populations, developing nations increasing their standard of living, accompanying increasing agricultural needs, etc. The issue with glaciers is just “the tip of the iceberg,” so to speak. But anything that can tie to “global warming,” especially one where typically 3rd-world areas supposedly suffer at the hands of us free-wheeling GHGs users, gets the headlines.
Directly, places like the La Paz, Bolivia area (2 million+) get a substantial portion from glaciers http://pubs.acs.org/subscribe/journals/esthag-w/2007/sept/science/ee_glaciermelt.html
It depends on how you define “stop melting.” If you define it as no changes on an ANNUAL scale but allow for advance and decline on a SEASONAL scale, then it is still a viable water source for some/much of the year. Water use tends to be highest at the time of year where glaciers would be supplying water (i.e., warmer months).
Riverwater, underground aquifers, seawater (via desalinization plants), rainwater, snowmelt, etc. Depending on where you live, none, some, or all of the local drinking water sources could be contributed to by glaciers.
Even if one assumes glaciers will generally disappear with global warming, the supposed increase in precipitation (which is what feeds and created the glaciers, after all) we will see from global warming would seemingly compensate in terms of drinking water. The difference between the two is the effect of storage. If there’s a village in Peru or something that relies on a glacier for drinking water, it’s not as feasible or readily affordable to construct storage infrastructure.
44, I’m not sure if I’m following all of the arguments either, but hydrology is a whole field in itself, and there are several ways in which water is impounded and then distributed over the course of the year, and not all of them involve snow, and not all of them involve surface rivers. I do see the logical conundrum though, of people who on the one hand say that retreating glaciers is a catastrophe that has to be stopped, and on the other hand the recognition that, precipitation patterns being equal, the flow from a stable glacier would be the same as from no glacier. Someone needs to ‘splain what’s so magical about “glacier water”.
Full disclosure: I do not drink bottled water.
The earth has been out of “thermal equilibrium” one hundred percent of the time since its existence. As meteorologists are taught early in their college careers, storms occur as a means of redistributing heat.
I am constantly amazed at the amount of bad meteorology contained in the “pro” AGW argument (that if we humans just went away, the earth would be in meteorological balance).
Of course you’ve read that. You’ve probably also read the Kilimanjaro was losing snow because of AGW. You’ve likely also read that sea levels will rise 100ft in the next century and that super hurricanes capable of turning the Atlantic ocean into a big sheet of ice are coming to town shortly.
Which means that for some reason the glaciers were exactly where they are now 7000 years ago and there was no AGW then. There are many things that can make a glacier retreat besides warmer temperatures. A couple of things would include increased hours of sunshine or decreased precipitation. I am prepared to go out on a limb and say that both of those conditions probably occur in concert. When you have increased sunshine (which melts ice) you also have decreased precipitation (which prevents ice from building). Maybe we are looking at long term wind and precipitation cycles and not temperature. I think I could reduce the average temperature yet increase sunshine and decrease precipitation and still have glacial retreat.
The question, “What do we do if the glaciers melt?”
The answer, We do as the people in the MWP did. We build cisterns to
store the runoff water available when it rains and to store the smow melt
water when it is abundant.
I think this has happened before sometimes to large degrees and some times
to smaller degrees. On islands that have no sorce of dependable fresh water
other than rain they build cisterns to store excess water during times of
rain or wet seasons.
Just a look at history so to speak… Some of the ancient cities built
cisterns that nearly undermined the entire city. just food for thought
and as always Steve you may snip
Bill
Or we build aqueducts, as they did in ancient times …
http://www.athenapub.com/pontdgd1.htm
Steve Mc:
This could be related to the angle of slope.
#66
I didn’t interpret Sean’s contribution as an attempt to argue with you. He linked relevant facts about the Bow River.
The key to point being made is that if the precipitation is constant X liters of water a year then once that reserve of glacier water is used the precipitation level is still the same X liters as if you stopped the glacier from melting. And only if you reverse the melting and the glacier starts growing will you then have less than X liters of water a year. If we want more than X liters of water for a certain year you have to melt the glaciers/reserves (again if annual precipitation does not change).
If you look a Google Earth you can see that the Great Plains are covered with many many enormous man-made reservoirs that are in some ways more manageable for humans than glaciers.
The micro climates around the glacier and esthetics for glaciers are a seperate arguement, as are the problems dams can cause.
#72 Out of date data (ends 2003).
woops, another try at that link
In April of last year Al Gore was in Calgary to preach and I was moved to write to the Herald editorial page. The final letter was dumbed down considerably but they still declined to publish it. I believe that the CA audience is sophisticated enough to manage the original and I submit the following:
April 26, 2007
The Calgary Herald, April 24, 2007
Gore brings global warming message to city
Once more Al Gore breezes through a town with his sound bites and slick multi-media presentation, proclaiming we must change or be doomed! His misrepresentations and alarmist approach have inspired me to action. His comment regarding retreating glaciers The Columbia glacier the source of water for many rivers is melting fast is typical. Anyone with a Google toolbar can quickly research the truth to that statement.
The Columbia glacier is one of a number exiting the Columbia icefield and is actually advancing (source: Canadian Glacier Inventory Project, McGill University, cgip.wetpait.com), but that is not the point,
The amount of ice-melt water supplied to the North Saskatchewan River from the retreating Saskatchewan glacier is 30 million cubic meters for each meter of loss at the surface. Annual ice loss is estimated at 1 to 2.6 meters (average 1.8 meters), supplying 54 million cubic meters of water. The total water passing through Edmonton via the N Saskatchewan is 7 billion cubic meters, meaning that the ice contribution is less than 1%, but thats not the point,
The flow of water in our rivers and streams is an interaction of precipitation supply, storage and drainage over the area of the watershed. Glaciers are only a part of the process and exist in one of these states:
i. Advancing, accumulating and storing water as ice for later release
ii. Retreating, melting and releasing water stored during accumulation
iii. Stationary, contributing nothing to the net flow of the system
This is the point; a stable glacier contributes nothing to the net water balance in a stream system, just as the absence of an ice accumulation contributes nothing. To use the existence, advance or retreat of a glacier as the proof or disproof of an argument is only political convenience and alarmism, as they are simply a visible reflection of the current state of balance of a very dynamic system.
Gores alarmist approach is summarized by Caleb Rossiter (Assistant professor, School of International Service, American University) who characterizes Gore in an October 2006 article thus; Gore emulates the two most misguided practices of mainstream of environmental lobbyists. He attacks opponents over who funds them and he generates hysteria about isolated events — Hurricane Katrina, chunks of ice calving (dropping off into the sea), ice cover melting on Greenland (Canadian glaciers), Antarctica, and Mount Kilimanjaro, droughts, and the spread of diseases and invasive species — whose causes are complex and often not mostly related to global or even local temperature.
I challenge the print media to research and challenge all of the issues so boldly asserted by Mr. Gore, who would have made much more of an impact had he condescended to speak with our democratically elected leader, Mr. Stelmach.
Roger Dueck, P.Geol.
Calgary
Groundwater depletion may be more important than glacier melting (see here.)
As an outsider (until now) to this debate I have noted one particular person who has a very selective way of responding (or rather not responding) to arguments. Mike Davies #30 and #40 makes simple but undeniable deductions. JohnB UK #36 makes a similar valid observation and so does Steve M #56. And that particular person is bender. Could bender please respond to these post?
Bender does admit that he is “not a glacier guy”. So he could learn something from Prof Cliff Ollier before he jumps to his alarmist conclusions:
Click to access greenland_and_antarctic_in_danger_of_collapse.pdf
I’m not selectively responding either, Mr Presumptive. I just got home from work and starting working backwards up the thread.
#90 I don’t think the discussion is silly. It’s been very informative at putting some logic and reason to all the alarmism that’s on the news these days about the “coming end of the World.”
#90. The discussion IS silly because losing a piece of one’s water supply – if it happens – is a problem. Yet you have people like Philip_B starting off by suggesting there is no potential problem, and Pat Keating saying “don’t give that cr*p about melting glaciers”. Pilip_B has since modified his position somewhat to say there could, in theory, be a small risk. When someone’s POV changes, I don’t think the discussion has been unproductive.
To the hardcore skeptics here (I won’t name names): how many of you read the Schindler & Donohue paper in #66? Be honest.
You know what the difference is between healthy and unhealthy skepticism? The unhealthy skeptic does not read on the other side of the fence. Unhealthy habits can lead to hard-to-cure disorders. Again, I won’t name names.
#95 Go ahead and make corrections, then. That’s what the thread is here for.
Just remember that a stable glacier has a finite rate of melting. A glacier that’s neither advancing nor retreating produces water. The cities aren’t dependent on the glacier retreating.
#98 But the Athabasca is undammed and its flows are declining as well. No?
So far I’m the only person to do so (without being prompted 🙂 ).
#90
It’s beyond silly; it has jumped the shark.
To paraphrase from Wikipedia:
Please Steve, cancel this thread and put it into syndication.:-)
This is a time-limited test of skeptic willingness to read on the other side of the fence. There sems to be a few Canadians in the crowd. In what year did Alberta agree to share it’s river water with Saskatchewan? What’s the share? Which reference cited above yields the answer? 10 digits total, no song and dance.
#103 Yes, the thread has strayed. That is exactly the point. It started off with Arthur Smith resonably discussing the use of glacial melt to estimate climate sensitivity. But then Philip_B and Pat Keating and Susann yanked it over into a silly discussion of whether the disappearance of glaciers would have any impact on stream flow.
Close it if you like, Steve M. The topic should never have come up in the first place. QED. There are bigger fish to fry than quibbling over stream flows.
#106 That’s exactly what I said on the previous unthreaded. I said modeling streamflow is a non-trivial issue, as Lins & Cohn would tell you. Not as complex as auditing a GCM, but non-trivial.
108, particularly seeing as most streams have an underground component.
If the glaciers all melt we’ll get our water at the supermarket, just like we do now.
For people who like to think black vs white alarmist-disaster vs zero-impact, it is important to realize there is a big middle ground range of possibilities.
Glacier melt is like the hurricane story: very weak A/GW link at best. Water mgmt on the prairies is always an issue. Hurricane damage on the SE coast is always an issue. Although the GW link is weak, it gets the story on the front page. I take the Pielke line: focus on the solution – damage control, insurance, adaptation – otherwise the GW line will distort policy toward something expensive and harmful.
#114 That point was granted already in #92 (and even earlier)
But also note that it is not just about glaciers, but snowpack. Rain in January goes to the ocean in January.
Through adaptive technologies. Things that cost money. Things that Philip_B argued will not be necessary due to zero impact.
Re #41 – All glaciers, at all locations melt during the summer. A glacier is a mechanism to transport ice from where it doesn’t melt to where it does. The point at issue is what effect glacier retreat (ice mass loss) has on ‘water availability’ and not the contribution of glacier melt. Steve M refers to this as ‘mined meltwater’ probably a good a term as any. Roger Dueck has got it right. BTW, Roger, Al Gore seems to confuse the Columbia Icefield in Canada with the unconnected Columbia glacier in Alaska.
Re#49 A point I made earlier. Large parts of the world like India have a summer rainfall max and any seasonal impact from glacial advance/retreat on river flows will be minimal. An error that this this study about Central , which otherwise shows glacial retreat will substantially increase river flows, makes. Central Asia has a summer rainfall max due to the intense Siberian winter high. Krgyzistan rainfall.
Re: #18
The levels of Lake Michigan have varied considerably over the years. I believe the 1960s had lower levels than today as I remember visiting a friend’s place “on the lake” where we walked many blocks to get to the lake. After that period I remember people being concerned with lake water eroding away the foundations of their lake shore homes. Over very long periods of times the lake levels have varied extensively.
How quickly people are want to accept potential natural variations as a problem related to AGW is a big clue to me as to where they stand on getting something done to mitigate AGW.
That glacier melting can have “bad effects” for the general population is much the same, in my mind anyway, as saying glacier melting will require changes to those adaptations that we have already made to past changes in that melting and if one considers having to make changes “bad” than of course it will be “bad” — even if the end result is better. In fact the better we make the end result of adaptation the worse a contemplated change from that condition will seem to be. If we really botched that adaptation than I would guess that many would feel any change/adaptation would be an improvement.
But the preliminary question that Steve M has posed here is what conditions relative to the present adaptation will result from (1) glaciers continuing to melt without a net replenishment, (2) glaciers being replenished for a net gain and finally I would assume (3) water availability when the glacier has completely melted away. For (1) and (2) cases we should confine our analysis to those cases where the temperature changes are not associated with going into the next glacier age nor into a period where the polar regions become tropical because those extremes will come slowly and have many other and more critical issues associated with them. With these restrictions we can then direct our attention to the intermediate cases. Clearly under those conditions a net loss or gain with the usual melting during the warm seasons would seem to have an insignificant effect on the local seasonal availability of water. On the other hand, when the glacier reaches such a diminished state that it no longer supplies sufficient or no water during the warming periods the flow and availability of water during that period must change. However, if the net precipitation of water has not significantly changed then any adaptation would involve either storing that precipitation as was accomplished naturally with the glacier or adapting to the less even flow of moisture to those areas as compared to the former glacier fed areas.
re 115 audit this.
Bender #105
You answer your own question a few posts later:
Bender #111
I’ll stop commenting when Steve M closes the thread. C’mon then, while it’s still open. Let’s see some data. Otherwise we’ll have to listen to Susann all night comment on the state of ______.
#126 EXACTLY. In fact I had just copied over your comments from the Spence cloud feedback thread, when I canceled, thinking ‘what’s the gd point’. Thank you for doing it for me.
#127
ok, now snowpack. refute it.
I’m not sure what you want me to refute about snow pack. Snow pack is the annually derived precipitation in the form of snow that melts in the summer. Thus, by definition, it does not contribute to glaciation. Further, the locations listed in Table 2 are all within the prairie areas, not in the mountains so they don’t pertain specifically to the problem of glacial retreat.
I am not trying to suggest that lack of water is not a problem in the Prairies. If warming does portend reduced precipitation in this region, there will be greater problems. I am simply arguing that the net contribution of glacial wastage to the Bow River flow is not nearly as significant or alarming as Schindler makes out.
“Global warming, if it were to happen, would reduce snowpack, increase winter rain and early spring runoff, thus exacerbating late summer drought.” Refute.
Or, if you want to take the mosher approach, explain why this is a red herring.
Re #135
Is this the accepted definition?
#137 Glaciers build by snow being packed and unmelted over multiple years. To the extent that shoulder season precip can fall as either snow or rain, glacial wasting is correlated with snowpack melt.
#136 I would assume glaciers can return after melting. It just takes many years of unmelted snowpack.
Disclosure: I’ve also stayed at a Holiday Inn Express.
I think that the situation is more nuanced than that. Mountain glaciers are sort of like a lake in that there is accumulation and flow, with discharge at the equilibrium line. The average residence time of snow in the glacier might be decades or centuries. For a glacier in equilibrium, the accumulation equals the melt, but they are not the same parcels of water. In a snowpack situation, the parcels are the same.
Re: 136
I agree that it is possible that global warming may actually contribute to reduced precipitation, lower snowpacks, prolonged periods of summer drought, etc. I am not familiar with what the GCM’s are predicting for the Western Prairie Provinces, but that doesn’t seem like an unreasonable claim (though for us on the west side of the Rocky Mountains, global warming seems to be bringing more precipitation, if the past two years are any indication). But as I say, water shortages in the prairies are a real and persistent problem, and climate change may therefore have a detrimental effect on the water availability.
The loss of glaciers may make a bad situation worse during periods of drought. But their current contribution to the overall water budget for the Bow catchment is relatively small. It may be prudent for water planners to consider enhanced water storage alternatives if precipitation patterns change substantially, but I really don’t consider the loss of glaciers, in and of themselves, to be a significant problem from a water supply perspective.
Re: 138
To be honest, I will have to confirm whether this is the definition formally accepted in the field, but it is the definition that I have always worked with in my professional career. In every context in which I am familiar, snowpack refers to that portion of snow that accumulates over the wintertime, and becomes available for augmentation of surfacewater or groundwater flow regimes in the summer. Snow that does not melt in the summer becomes glacier. From the Schindler paper, they note the number of days with snowpack, which implies that it is only seasonally persistent, not inter-anually.
I think this is a good question. When someone asserts that melting glaciers is attributable to temperature change, then you have to ask the attribution question – the same question we ask in terms of CO2 causing temperature change. Schindler doesn’t use a glacier model (building, wasting dynamics) to attribute wastage to temperature rise. Should he? This seems like a productive line of inquiry available to any skeptic. Why not use it? Look how much ground has been gained poking at the GCMs.
If you look at a satellite picture of the Prairie Provinces in Canada, you will see trillions upon trillions of gallons of water. There is a lake every 2 miles in the northern parts.
If you get lost in the woods in Northern Saskatchewan, you will forever be walking around lakes until you find a road. If you get lost in the woods at Fort McMurray, you will be walking in swampland forever (until you find one of the huge open pit oilsands operations.)
Sorry, there will never be a shortage of water in the Canadian prairies (until the 2 mile high glaciers come back.)
#137 You can’t win against cattle ranchers and grain farmers who are vulnerable to natural drought, whose profit margins are incredibly slim, and who don’t believe in taxes to pay for adaptation infrastucture. Admit the risk is there, but downplay urban elitist alarmism.
You can’t win against urban polar bear hugger theorists; they don’t pay attention to data.
Bender – 129
Global warming, if it were to happen, would reduce snowpack, increase winter rain and early spring runoff, thus exacerbating late summer drought. Refute
For full disclosure – I am a hydrologist, located in Canada, so I understand the effect of snow processes on hydrology.
Yes, under a warmed climate, snowpack would be reduced. Winter precipitation would be more rain than snow. However, spring runoff would not increase, but rather decrease. The majority of spring flows are derived from snowmelt, without the snowpack to drive the spring freshet, we’d have lower spring flows. Yes, global warming may reduce snowmelt driven flood events! You don’t hear that from Gore do you?
Instead of the precipitation accumulating throughout the winter, then producing streamflow in one intense 1 week period, we’d have numerous small melt events (or rainfall only events) occurring throughout December-March. This would decrease the variability of streamflow, while increasing the average flow through the winter period, and would actually allow more water to be utilized.
Now, summer flows (low flows).
Low flows are sustained from discharges from some sort of storage element. Storage elements can be man-made (dams), or natural (melting glaciers, wetlands, or aquifers discharging to surface). In most non-arid areas, the dominant storage element is the groundwater system. Obviously aquifers (unconfined) are recharged from water which infiltrates the surface of the soil. In current Canadian conditions, the upper layer of soil is frozen during winter months, and almost completely impervious. Any precipitation that reaches the soil surface, can only directly runoff to the watercourse. Little to no recharge to the groundwater system.
Now let’s go to a warmed climate, where frozen ground conditions are a thing of the past, and we have frequent, but small, snowmelt events. When precipitation reaches the soil surface, it no longer finds a frozen, impervious surface – it can actually infiltrate, recharging the aquifers that sustain river flows during low flow periods. We’re no longer having one big melt event over frozen ground, but many small melt events over unfrozen ground. The end result is more water getting into the ground. Global warming would actually cause groundwater recharge to be increased, not decreased. Whether the aquifer had sufficient storage to effectively make use of this increased recharge, would depend on the specific characteristics of the aquifer.
Evapotranspiration (ET)? Speaking from my experience in Southern Ontario, we already get to wilting point in the summer (i.e. we can’t ET more water during the summer, there’s none there to lose). Winter? Perhaps, but it would likely be marginal – ET largely relies on vegetation to remove water from the soil column. There’s simply not enough sunlit hours for vegetation to be active in Canada during the winter (regardless of temperature).
You heard it here first – global warming will reduce floods and increase groundwater supplies in Canada 😉
Suse:
Brief excerpt from opening of referenced article:
Lovely article; but they do not detail reasons for the decline in water level; can we diverge in that direction momentarity?
Opening excerpt from an article in The Sault Star (Ontario):
Website of the International Upper Great Lakes Study Board: http://www.iugls.org/en/home_accueil.htm
snip
The glacier impact on water supply is zero compared with the impact of the loss of this resource …the mining of the Ogalalla Aquifer.
#97
Bender, Bender
Worst offender.
Take too long, mate. I’m busy designing dams.
re 142. beaver on jack.
Enough free time to churn out nonsense, yet too busy to counter with facts. You see that pattern sometimes. Keep it up. Step right up and discredit yourself.
#4:
#145:
AFAICT this thread is done.
Hey, all this Canada talk – I’m beginning to wonder if climateaudit is, rather than being biased due to oil and gas industry ties, instead a front for Canadians hoping global warming will finally accomplish their dreams of taking over the world! Be forewarned 🙂
RE: 147 and 148, got it and got it.