The recent Arctic blast that gripped much of the nation will likely contribute to a healthy rise in Great Lakes water levels in 2014, new research shows.
But the processes responsible for that welcome outcome are not as simple and straightforward as you might think.
From the University of Michigan
Great Lakes evaporation study dispels misconceptions, need for expanded monitoring program
ANN ARBOR—The recent Arctic blast that gripped much of the nation will likely contribute to a healthy rise in Great Lakes water levels in 2014, new research shows. But the processes responsible for that welcome outcome are not as simple and straightforward as you might think.
Yes, extreme winter cold increases ice cover on the Great Lakes, which in turn reduces evaporation by preventing water vapor from escaping into the air. But this simplistic view of winter ice as a mere “cap” on Great Lakes evaporation is giving way to a more nuanced conception, one that considers the complex interplay among evaporation, ice cover and water temperature at different times of year.
In a report released today by the Great Lakes Integrated Sciences and Assessments Center (GLISA)—a federally funded collaboration between the University of Michigan and Michigan State University — a team of American and Canadian scientists notes that while ice cover affects evaporation, the reverse is true as well: evaporation rates in the autumn help determine the extent of winter ice cover.
High evaporation rates in the fall can nearly offset water-level gains that result from extensive winter ice cover, complicating efforts to forecast Great Lakes water levels, which have declined in most of the lakes since the late 1990s, rebounding somewhat during a wet 2013.
The newfound appreciation for evaporation’s varied roles reveals gaps in our current understanding of fundamental environmental processes and highlights the need for sustained funding for the project’s Great Lakes evaporation monitoring network, said John Lenters, the study’s lead investigator and a senior scientist at Ann Arbor-based LimnoTech, an environmental consulting firm.
The binational group’s network of five stations is one of the few sources of direct, year-round observations of Great Lakes evaporation.
“It’s our hope that we will soon have the funding and infrastructure in place to maintain—and even expand—the network well into the future,” Lenters said. “This will be extremely important for improving Great Lakes water-level forecasting and for understanding the long-term impacts of climate change.”
The study by Lenters and his colleagues is the first coordinated effort to study evaporation across the Great Lakes. In addition to Lenters, the research team consists of Christopher Spence of Environment Canada, Peter Blanken of the University of Colorado, John Anderton of Northern Michigan University and Andrew Suyker of the University of Nebraska.
By piecing together the results from several studies, Lenters and his colleagues showed that years with high Great Lakes ice cover require a large amount of heat loss from the lakes in the preceding autumn and early winter to cool the water enough to form ice. And one of the most effective ways for a lake to lose heat is through evaporation, which means that extensive ice cover is actually an indicator of high evaporation rates prior to a high-ice winter, according to co-author Blanken.
Team members used funding from a 2011 GLISA grant to integrate their independent efforts, underway since 2008, to monitor and understand the impacts of climate variability and change on Great Lakes evaporation. The 11-page white paper released today highlights a few of the results.
“No two years are alike when it comes to Great Lakes evaporation, ice cover and water temperatures, but the recent documented changes in the lakes’ water balance are aligned with predictions associated with climate change,” said Environment Canada’s Spence.
“That’s why these new measurements over each of the Great Lakes have been so valuable to better understand these seasonal, inter-annual and long-term variations,” he said.
The recent cold spell, blamed on an errant polar vortex, provides a striking example of how Great Lakes evaporation sometimes defies expectations.
While examining meteorological data from an island on Lake Superior, Lenters found that evaporation rates during December 2013, a cold month, were about 60 percent higher than they were in December 2011, a much warmer month.
“Most people would find this counterintuitive,” Lenters said. “Why would a lake evaporate more rapidly during a colder month? The answer, it turns out, lies within the lake itself.”
Relative to the air, December and January water temperatures can be surprisingly warm in deep lakes like Superior. In early January 2014, the lake was 30 to 40 degrees warmer than the overlying air, according to Lenters. That large temperature contrast caused a steep moisture difference which, in turn, led to high evaporation rates, he said.
So what does all this mean for Great Lakes water levels in 2014?
Although the recent cold spell has led to high evaporation rates this winter, the extensive ice cover is likely to stick around longer into the spring than is typical. That may lead to cooler summer water temperatures and a later start to the 2014 Great Lakes evaporation season.
“Together with high spring runoff from this winter’s heavy lake-effect snowfall, it would be reasonable to expect a healthy rise in Great Lakes water levels this year,” Lenters said.
In addition to funding from GLISA, the investigators received support from the International Upper Great Lakes Study through the International Joint Commission. The co-directors of GLISA are Don Scavia at U-M and Thomas Dietz at Michigan State University.
“A new understanding of the impacts of climate variability on Great Lakes evaporation is emerging as a result of this GLISA-funded project,” said Scavia, director of the Graham Sustainability Institute, which oversees the GLISA program at U-M.
“In light of these new findings, continued long-term monitoring of Great Lakes evaporation and related hydrological processes is paramount for understanding and predicting the future impacts of climate variability and change on Great Lakes water levels.” “Understanding how lake levels are changing is very important to our region,” said Dietz, a professor of environmental science and policy at Michigan State. “This affects shipping, recreation and infrastructure on the lake shore.”
The reduction in great lake water levels is mostly dues to the dredging of channels for shipping and the increased erosion of the waterways due to the greater current flow and disruption of the channel cause by the dredging and is little to do with climate.
Ho hum.
They almost had me thinking they knew what they were talking about until the brought up global warming. With that, I know they were just after more funding.
Somewhere in all that verbiage is the watermelons’ new refrain “warm makes cold”……
“…reveals gaps in our current understanding of fundamental environmental processes and highlights the need for sustained funding for the project’s Great Lakes evaporation monitoring network…”
Translation: “We don’t know, but we want more money, so as to make our ignorance more accurate.”
And varying precipitation in the watersheds feeding the Great Lakes is unimportant? There is a large direct precipitation correlation, and all else (summer evaporation, winter ice extent) is rounding error.
Would not humidity levels affect evaporation rates as much (or more) than temperatures? They make no mention of that.
Get a load of the fallacious reasons they give for more funding : they claim knowledge of how the lakes’ water levels change is important because of the value of the lakes etc etc. Now exactly why do these folks believe that more knowledge will enable anyone to do anything about future
changes in water levels?
Sounds like this could lead to more Mid west flooding this spring. Sometimes I’ve wondered why some sort of flood pipeline system couldn’t be developed that could move water from a flood area to a drought area? We can pipeline oil, Water wouldn’t be an environmental issue like the keystone pipeline.
Just throwing it out there…..
R Abbott @ 7;04am has it correct, especially for Huron / Michigan. Here’s a link to check the water levels c/w historic averages;
http://www.waterlevels.gc.ca/c&a/bulletin_e.html
Translation: The purpose of all words previous to this was to secure funding for “monitoring” of the lakes because we can’t just have water levels wandering around on their own unmonitored.
So. Too warm raises sea level. Too cold raises lake level. Do I have that about right?
Too cold (or early cold in this case) causes ice to form earlier in the season, thus reducing evaporation, leading to higher lake levels. As a side benefit, early ice also reduces or eliminates lake effect snow, which is good news for the west coast of Michigan.
blame it on anything but the cold…
…now it’s because it was too warm before the cold
Evaporation of Lake Michigan is conventionally thought to be ~30% of total loss.
Roderick, Michael L. and Graham D. Farquhar (2002). “The cause of decreased pan evaporation over the past 50 years”. Science 298 (5597): pp. 1410–1411 http://www.sciencemag.org/cgi/content/abstract/298/5597/1410. Bibcode:2002Sci…298.1407D. doi:10.1126/science.1075390. PMID 12434057.
Brutsaert, Wilfried (2006). “Indications of increasing land surface evaporation during the second half of the 20th century”. Geophysical Research Letters 33 (20): pp. 1410–1411. Bibcode:2006GeoRL..3320403B. doi:10.1029/2006GL027532
Providing the water level does’nt fall to a critical level, what does it matter what level it is, and what can they do about it if they do find out what causes the level to fluctuate? Some of these research guys seem to have a very easy ride after they have persuaded some charitable funding body to part with their cash.
There was a Quebec? engineer, some years ago, who did some calculations on damming off 1/2 of Hudson Bay and diverting the fresh water south.
To assuage the great fear of that time, that the Great Lakes were vanishing.
I have forgotten all the good details, as in name, where published and so on, but the compelling case the man made lingers on.
I skimmed the above posting, I saw no mention of the obvious effect of ice cover, that it restricts the out flows from the lakes.
Ice encrusted river beds are able to flow less water.
A frozen Niagara Falls helps the local hydro conserve water.
100 ft of 1 ft thick surface ice in a 100 ft channel is 10,000 cubic feet of blockage.
Up north here this blockage of the lake outflows is countered by the near complete freezing of the inflows so lake level drop under the ice.
In the south more surface water continues to run off so lake levels may rise.
All I can say as a native Michigander – a rise in the lake levels would be very welcome.
It was climate change that brought the lakes into existence.
John Robertson, you beat me to it! But you had the same thought as I did when I first saw this story – increased ice in the system is just like putting flow restrictions in a pipeline. The more restriction, the less flow, and the more the water backs up. It’s just fluid mechanics.
George Lawson says: January 22, 2014 at 8:30 am “Providing the water level does’nt fall to a critical level, what does it matter what level it is, and what can they do about it if they do find out what causes the level to fluctuate? [ … ]”
Well, an anecdote, my community of ~700 just backed a $5 Million grant to dredge our harbor channel for a private ferry company. To a logical first approximation, plug the holes in a leaky vessel to make its level rise.
There is a lot of ice cover on the Great Lakes so far this year:
http://www.glerl.noaa.gov/res/glcfs/glcfs.php?lake=l&ext=ice&type=N&hr=00
Again the weakening polar vortex ad hoc BS…
Yes, it can be seen that Lake St. Clair is 100% and the Lake Michigan system is filling. So let’s put the plug back in the St. Clair River – while the dollar has value enough to still afford the effort.
“No two years are alike when it comes to Great Lakes evaporation, ice cover and water temperatures, but the recent documented changes in the lakes’ water balance are aligned with predictions associated with climate change,” said Environment Canada’s Spence.
I’m sorry – at this point, what exactly isn’t aligned with predictions associated with ‘climate change’?
@Peter in MD,….Lake Levels could rise several feet and it’d have no effect on flooding.
@ George Lawson…Lake levels are most critical for commercial shipping and boating. The lower the levels, the shallower the channels are. This means the freighters have to carry much less. So you’re left with 2 options, ship less via the lakes OR make a lot more runs. Recreational boating takes a major hit as well (a big part of Michigan’s summer economy) because as Doug Huffmann points out, marinas will dredge so they can keep putting boats in.
Richard Abbott
Your claim regarding the cause of the low Michigan/Huron lake levels is only your opinion. The Joint US/Canada commission thinks differently.
“The International Joint Commission, the board that oversees U.S. and Canadian boundary waters issues, agreed to hire a team of scientists referred to as a “study board” to look into the St. Clair question. In 2009 the study board released a report that concluded erosion since the 1960s dredging had unexpectedly lowered the lakes by about 3 to 5 inches, though it said the erosion was not ongoing. The report also blamed changing weather patterns and the earth’s crust rebounding as two other significant factors behind what it said was a loss of 9 inches in the difference between Michigan-Huron and Erie from 1962 to 2006.”
You might be surprised to know that Lake Superior, Erie and Ontario are at or above the 1918-2008 average water levels and that St. Clair is just a tad below the 1918-2008 average. Lake Michigan/Huron is now about 11.4″ below the mean and has recovered significantly in just a year.
Daily water levels can be found at: http://www.glerl.noaa.gov/data/now/wlevels/levels.html
Based on historical records, lake levels seem to follow a long term cycle. In 1987 water was sloshing over Lake Shore Drive in Chicago and the impending “disaster” was all about the rich losing their precious shorelines due to erosion. 25 years before that Lake Michigan had set record low water levels prior to the “dredging” you are probably referring to. 25 years after the record highs in the 80’s, Lake Michigan approached or set new record lows in 2012. Notice any pattern? These guys did: http://phys.org/news/2014-01-scientists-id-year-water-level-great.html
I hope you have a better understanding of the issue now.
Thanks
William
“In light of these new findings, continued long-term monitoring of Great Lakes evaporation and related hydrological processes is paramount for understanding and predicting the future impacts of climate variability and change on Great Lakes water levels.”
______________________
The grantsmanship is obvious, but the paper lacks the shrill tone of previous “studies”.
“Climate Variability” may not represent a sea change in rhetoric, but maybe we could just call it a lake effect.
This is pretty funny. People who live and work on Lake Michigan know well that the lake level is cyclical on a decadal scale and that highs and lows always make news. They also know that “scientists” and the Army Corps always shrug their shoulders and say they don’t know why but they do know that it’s not something they cause or control. And in the grand scheme of things, it’s not something to worry about.
Right now (2012 data), the level of the great lakes is about a foot below its 1918-2012 mean and only one lake (Michigan-Huron) set a low record in one month of 2012 — that’s one out of 60 (five lakes, 12 months).
http://www.lre.usace.army.mil/Portals/69/docs/GreatLakesInfo/docs/WaterLevels/LTA-GLWL-English.pdf
I know one Lake Michigan waterfront homeowner who installed an expensive seawall during one of the high water episodes to prevent his land and house from being washed away. Five years later, the lake had receded and he had a beautiful beach BELOW the seawall. He then installed a ladder to get from the beach, over high and dry seawall to his house.
I don’t know why “we” don’t understand what’s going on in a lake that can be surveyed in a year by a man on a horse. Mostly I don’t know why we care.
Almost exactly a year ago we had this eco-worrier.
Maybe it is feeling the effects of a changing climate. Climate change is the default sceptical position – ‘coz’ that’s what it ‘doz’.
In re expensive lakeshore properties, who’s going to cry the loudest when the levels recover or exceed experience?
Checking out ice levels on the Great Lakes and they are at levels for the week of Jan 22 not seen in 20 years, still short of the 80’s but much higher than the past couple of years.
http://iceweb1.cis.ec.gc.ca/Prod20/page2.xhtml?CanID=11080&lang=en page
http://ice-glaces.ec.gc.ca/prods/CVCHACTGL/20140120180000_CVCHACTGL_0007477168.pdf plot
Whenever I see the words in print “as a result of climate change” I can only compare it to the internet meme “because….. Aliens!”
The explanation harkens back to an unscientific time when man was searching for explanations for common but awe inspiring natural events. What is lightning? Its some god throwing down bolts as a result of us humans offending him in some way. Earthquakes? The god of the underworld is displeased by us so we need to heap a few more sacrifices on the altar. Crops fail, climate change, er, I mean the earth goddess is displeased and time to sacrfice a few more virgins.
Its getting to the point of ridiculousness. Like anything else its a money thing tied to a boondoggle of money to fund a climate hysteria industry that profits from prophesizing doom just far enough in the future to insure continued funding until they hit retirement age.
Another source
http://www.glerl.noaa.gov/data/now/wlevels/dbd/GLHCD/
It appears that the water levels tend to have some periodicity. Related to temperature? I remember back in the ’80’s there was lot’s of handwringing about the eastern shore of Lake Michigan washing away because of the high water levels. Houses on bluffs had a great chance of falling into the lake. Then, in the ’90’s the Michigan/Huron levels dropped drastically. The link tracks my memory. I don’t think it was all due to evaporation.
http://ice-glaces.ec.gc.ca/prods/NAIS25WCT/20140121180000_NAIS25WCT_0007477301.pdf
The picture of Lake Superior, and to a lesser extent Lakes Michigan and Huron, is the impression that ice has yet to form over the deepest part of Lake Superior. The Environment Canada sourced picture suggests a “chimney” of open water with 9/10 th ice thickness covering the periphery of the Lake and the open water portion allowing Lake Superior a way to release its heat. When the Alberta Clipper comes roaring down from the Arctic Circle, the air is bitterly cold and the moisture content is very low. The combination of a very dry air compared to the Lakes open water rapidly skimming the open water of the Great Lakes, whisks away the surface water vapor and its associated heat. Lake Superior won’t freeze over until the retained heat reduces the gradient of Lake surface temperature to Arctic air temperature to allow surface freezing.
Looking at Lake Erie and Lake Ontario; Lake Erie is shallow at 62 ave depth and 210 ft max., Lake Erie’s surface is frozen over but the relatively warm water flowing from Lake Superior through the St. Mary’s River and the relatively warm water of Lake Huron/Michigan flowing under the surface ice of Lake St. Clair and Lake Erie all ends up in Lake Ontario so that Lake Ontario will not freeze over until the retained combined Great Lakes heat is dissipated. The reason Lake Ontario is not frozen over is not that it is deeper than Lake Superior which is 483 ft ave and 1332 max. Lake Ontario depth ave 283 ft and 802 max. Rather, Lake Ontario is fed warmer water from further up stream. My expectations are that when Lake Superior freezes over, Lake Ontario will still have a large open water portion.
The Great Lakes usually get their heat from the short wave radiation from the Sun as well as the warmth of the melting waters of the water-shed land surfaces. Ice covered rivers still have water flowing underneath the ice. I imagine the Great Lakes as a huge river system, with the identified Great Lakes as wide and deeper places along the way. This notion was suggested to me after reading as a young child the book: Paddle-to-the-Sea by Holling C. Holling.
My “projection”: Lake Ontario won’t freeze over until the surrounding land surface and other Great Lakes waters up stream of Lake Ontario are frozen over first.
Water levels in the Great Lakes river system are dependent upon the feeding watershed, principally snow fall in Northern Ontario, and evaporation, which comprises @ 95% of the water loss. Depending upon the “bottle-necks” to Great Lakes egress rivers: St Mary’s for Superior, St. Clair River for Huron/Michigan, Niagara River for Erie, and St Lawrence River for Ontario, there is little room for man to manipulate the Great Lakes water levels.
For the long term, I suggest sailing a boat without a keel, rather a dagger board or some such contrivance. Then all one needs is two feet of water which should remain in the Great Lakes until I am long gone and my ashes spread to the four winds.
John Lenters told Nat Geo in a Nov 20, 2012 article:
“Lake Superior’s rapid warming is like a canary in the coal mine,” Lenters told me. “We’re seeing changes in ice cover, water temperature, and evaporation that indicate major shifts are underway on the world’s largest lake.”
I also particularly like the caption on one of the photos: “Experts predict that Lake Superior water levels will continue to decline, on average, due to increased evaporation rates caused by climate change.” Photo by John Lenters.
http://newswatch.nationalgeographic.com/2012/11/20/climate-change-and-variability-drive-low-water-levels-on-the-great-lakes/
Almost a year later the canary is tweeting loudly:
– Lake Superior’s current average surface temp is 0.70 deg C, coldest temperature at this time since data available in 1995 according to NOAA: http://coastwatch.glerl.noaa.gov/statistic/
– Superior Ice coverage is at 53% and rapidly growing. It will certainly freeze over this season given the water temps, timing and 1994-like jet pattern we are in: http://www.glerl.noaa.gov/res/glcfs/glcfs-ice.php?lake=s&type=F&hr=01
– Since Lake Superior is dimictic, meaning it turns over 2x per year, the heat is not “hiding” at the bottom, there’s no warming “trend”, once the Lakes cool to this level any trend is over: http://www.seagrant.umn.edu/superior/processes
– Also according to NOAA, Superior is at normal levels for this time of year: http://www.glerl.noaa.gov/data/now/wlevels/plots/sup_lvl.gif
The “funding” they are hoping for is really cashing in on stoked concerns for Lake levels and hitching on to the Global Warming gravy train to study something about which they already have conclusions. This is a case study of alarmist science scam.
Coming from the St. Clair River area, I remember the ice jamming in the channel between Harsen’s Island and the mainland, as well as on the Canadian side. This caused flooding along the river all the way up to Port Huron (maybe more). My dad still lives in that area and says the water is higher right now than is has been in a long time -nearly 2 ft higher – and the ice breakers are running non-stop trying to keep the channels ice free. The highest the water ever got (in the 80’s) was about 4 ft from his front door, but it is no where near that now. If the ice jams solid like it did when I was a kid – all bets are off, and there is nothing like being forced out of your house by freezing water…
Meanwhile back on the majestic Lake Superior watershed, in the midst of a minimally impacted and scenic forest/wetland complex, they are getting set to install hundreds of giant fans…
http://www.pnas.org/content/early/2010/09/28/1000493107.full.pdf
[ Relative to the air, December and January water temperatures can be surprisingly warm in deep lakes like Superior. In early January 2014, the lake was 30 to 40 degrees warmer than the overlying air, according to Lenters. That large temperature contrast caused a steep moisture difference which, in turn, led to high evaporation rates, he said. ]
Therefore, the most obvious solution is to increase global warming of the air.
Problem solved. Doh….
I really hate trying to determine what a report or study is really saying based on a press release, so here is a link to the actual report ( http://glisaclimate.org/media/GLISA_Lake_Evaporation.pdf ) – via the news release from the University of Michigan ( http://ns.umich.edu/new/releases/21911-great-lakes-evaporation-study-dispels-misconceptions-points-to-need-for-expanded-monitoring-program ).
Their study details the preliminary understanding of the evaporation mechanisms, shows a relationship between the ice cover during the winter and lake levels in the following spring and summer. the relationship between ice cover and surface temperatures from the preceding summer and fall and several other relationships which could affect evaporation and lake levels. It covers a period from the early 70’s to present day but tends to concentrate on the most recent data – probably because that is the most extensive and relevant. If you skip to the summary of the report you will find their basic conclusion is that the mechanism of evaporation for the lakes is much more complex than they initially thought making it difficult to determine the impact of evaporation on climate variability without further study and expansion of the program to include more sampling stations. Overall, it looks like a solid report.
Hmmmmm; did not see any mention of crustal rebound affecting lake levels.
The Great Lakes Basin rebound from the last glaciation may be the single biggest reason for levels dropping. That and hydro generation at Niagara Falls. The St. Clair Cut just made freighter passage easier while increasing flow into Lake St. Clair and thus Lake Erie offsetting the increased flow thru the penstocks at Niagara Falls.
Does anyone remember Lake St. Clair in the late 1960’s. The water level was so low and everyone thought Lake Erie was going to be a ‘dead’ lake. I’ve heard about the 10 yr. lake cycle and I think that’s what we are experiencing.
crosspatch says:
January 22, 2014 at 8:02 am
Translation: The purpose of all words previous to this was to secure funding for “monitoring” of the lakes because we can’t just have water levels wandering around on their own unmonitored.
———————————————————————————————————————-
I like that. Future headlines “Meandering waters stirring up trouble in Great Lakes Region. The National Guard with a new contingent of Climate Change Guards have been dispatched to nip this insidious development in the bud”.
Greetings, I am currently typing from my residence on the southern shore of Lake Ontario (near Rochester NY), we call it the North Shore of the USA. I see it’s behavior everyday from my back windows which are ~100 feet from the shoreline. I’ve lived 5o plus years within a short distance from Lake Erie, Lake Ontario and Niagara Falls.
Just a few misconceptions in the comments;
“I skimmed the above posting, I saw no mention of the obvious effect of ice cover, that it restricts the out flows from the lakes.”
Not really, the outflow from Lake Erie is water. A large “ice boom” (string of large logs chained together) is put in place every winter (from Buffalo NY to Fort Erie Ontario) to keep most of the ice in the lake. This protects downstream infrastructure (docks, bridge piers, marinas, etc.). It is removed in the spring (schedule varies depending on the amount of ice, usually Mid April). Once they pull the boom out the river fills with ice for a week or so and the temperatures near the river are noticeably cooler.
“Ice encrusted river beds are able to flow less water.’
Ice floats, the river bed rarely sees the ice. Although some sport fishermen (fisher person ?) are complaining that the ice boom retards some natural “scraping” of the river bottom by ice. They claim this stops some spawning areas from being “refreshed” like they used to be. The sport fishermen want the ice boom eliminated. The sport boatmen want it kept so they don’t have to construct seasonal docks.
“A frozen Niagara Falls helps the local hydro conserve water.”
Not really, the water intakes for the hydro projects at Niagara Falls are 1 to 4 miles upriver from the brink of the falls. The current is so fast that little ice has any chance to accumulate near the intakes. Because of the general ice free nature of the water near the falls it attracts many interesting migrant birds (things like purple sandpipers, etc.) that do not show up elsewhere in upstate NY. And the hydro project uses water from the constant flow of the river. Not like the Hoover dam that stores years and years worth of water. the Hydro projects have pumped storage reservoirs, but these are filled at night with pumps to supply the peak electricity needed in the daytime.
“The reason Lake Ontario is not frozen over is not that it is deeper than Lake Superior which is 483 ft ave and 1332 max. Lake Ontario depth ave 283 ft and 802 max. Rather, Lake Ontario is fed warmer water from further up stream.”
Perhaps, but Lake Ontario is also further south than Lake Superior, and a wee bit closer to the Gulf Stream. I am not aware of any reports of Lake Ontario freezing over completely in my lifetime. And no ice-breaking boats have ever (to my knowledge) been deployed there.
I my opinion, all of this; “The lake levels depend on evaporation during the fall” is “counterintutive” nonsense. The lakes drain a huge area of land, from the NY/Pennsylvania border on the south all the way up about half way to Hudson bay. Any variation year to year in the precipitation over that huge area will affect the lake levels. And these variations flow downstream through several river “bottlenecks”, heck a rainy year in Duluth probably takes 9 months to get to my backyard. Any body that claims to understand all of these effects is kidding themselves.
The lakes do what they do, smart people prepare, fools pretend they can “model” it.
Cheers, Kevin
My word doesn’t the evaporation get deposited in the form of lake effect snow or rain? Where does that end up? I was hoping that the lake level which has been sadly low for a number of years would be predicted to naturally rise again because of some believable cyclical theory. When the researchers start saying hot is cold and cold is hot and they need more money my eyes glaze over.
“Most people would find this counterintuitive,” Lenters said. “Why would a lake evaporate more rapidly during a colder month? ”
______________________________________________________
Another indication that ‘climatologists’ have no concept of thermodynamics. Evaporation is driven more by water temperature than air temperature.
Rising water levels of the Great Lakes are good. However, it doesn’t help when Nestle is sucking out the lake water to bottle and sell it. Why isn’t the government filtering that water and providing it to the residents in the form of municipal water? Nestle can steal lake water, filter it and sell it as bottled water but the residents of Michigan have to drink unfiltered tap water that contains abnormal levels of heavy metals and other pollutants. That seems fair (*sarcasm*).
I would definitely have a closer look at the large scale dredging of St. Clair river in the 1930’s &. 1960’s and the subsequent erosion. It is the single outlet of Lakes Michigan and Huron, its cross section has a huge effect on water level of said lakes. If levels are to be kept in tight bounds, some water work is inevitable, nature is not motivated to do that for us.
You are forgetting about the Chicago River,, whose course was reversed in 1900 so instead of flowing into Lake Michigan, it took water out of the Lake and eventually deposited it into the Mississippi River. At the time, sewage and other industrial waste dumped into the river were polluting the city’s water supply from the lake, so they undertook a major engineering project to reverse the flow. In 1999 this project was named a “Civil Engineering Monument of the Millennium” by the American Society of Civil Engineers. From the reference linked above:
So if the lake level is high, blame the Supreme Court. Likewise if the level is too low …
I managed to botch the link to the Chicago River reference here it is again . Or if that fails, copy&paste this:
http://en.wikipedia.org/wiki/Chicago_River
Meanwhile the Great Lakes ice cover story is interesting also.
http://www.upnorthlive.com/news/story.aspx?id=997186#.UuEmRtLnZpU
The St. Clair River drains 182,000 cubic feet per second from Lake Michigan/Huron. The outflow to the City of Chicago including the drinking water and the Chicago River is just 3,200 cfs, so not a significant contributor really. I live in Chicago on the Lake, these past two weeks there is a lot of ice and lake freighters are having a hard time. As an earlier poster mentioned evaporations is not caused by the difference between the air temperature and the water temperature. Water evaporates from the top super-thin layer, the temperature of which determines the evaporation, combined with the relative humidity of the air immediately above it. I went to the U of Michigan, these guys embarrass all Wolverines…