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  • USA Today provides an American perspective on the increased risk of flooding from Lake Ontario, in upstate New York.

  • Global News notes that the Toronto Islands are now effectively off-limits to visitors until the end of July.

  • Toronto Life shared Daniel Williams' stunning photos of the flooded Toronto Islands.

  • Inside Toronto notes that many people are still going far too close to the unstable Scarborough Bluffs.

  • The Toronto Star noted that the marina at Bluffers' Park is facing flooding.

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The Toronto Star's Betsy Powell describes the many problems faced by Wasaga Beach, a resort community on Georgian Bay popular with Toronto vacationers that has been faced with falling tourist numbers in recent years. (I should mention, for the record, that I have never been here.)

A bundled-up couple walking a dog and a lone snowmobiler had the world’s longest freshwater beach to themselves on a recent morning as a frigid wind swept across Georgian Bay.

“Nothing down here will open. Who’s going to come and park here when it’s cold?” Deputy Mayor Nina Bifolchi says, driving past a stretch of closed-for-three-seasons fast-food eateries and bars facing the beach.

She was on the losing side when council voted to buy the properties for $13.8 million in 2015, using money borrowed from a bank and the province.

That’s no small sum for the town of 18,000 that will collect $20.3 million in property taxes this year and spend $48 million in operating and capital costs.

But waterfront purchase proponents, led by Mayor Brian Smith, argue Wasaga Beach needed a “bold” step after a steady decline in tourists — the town’s economic lifeblood — of roughly 100,000 a year between 2002 and 2012, compounded by a massive fire in 2007 that destroyed a bustling street mall in the beach’s east end. The mall was never rebuilt and has since been replaced by a beer garden and kiosks.
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Torontoist carries a post from Catherine McIntyre, writing for the Toronto and Region Conservation Authority, looking at the revival of local fisheries.

Some of the best fishing is in our back yard.

Two young anglers, each no more than 12-years-old, wade in the creek with their fishing rods as the sun breaks through the last of the rain clouds. It’s spawning season for Chinook salmon and the kids, along with hundreds of other community members, have congregated near Highland Creek for the seventh Annual Salmon Festival, where they hope to catch—at least a glimpse of—the fish swimming upstream.

“It still amazes people that there are salmon in these rivers,” says Arlen Leeming, a manager at Toronto and Region Conservation Authority (TRCA). “It wasn’t always like this,” he adds, as we walk along a deer path near the riverbed. In fact, 200 years ago, the waterways that feed into Lake Ontario were teeming with native fish populations. The Atlantic salmon was so abundant that inmates at the Don Jail eventually refused to eat any more of the fish, caught fresh and frequently on the prison premises.

In the decades that followed, industrialization, urbanization, and neglect lead to polluted waterways and the demise of many fish populations, including Atlantic salmon. In 1969, the Don River was ceremoniously pronounced dead; other nearby rivers were scarcely healthier. By 1985, the Toronto region was dubbed an “Area of Concern”—an environmental hazard zone—on the Great Lakes.

Since then, the TRCA has helped carry out myriad projects to boost the health of Toronto’s rivers and creeks and restore fish habitats. In 1987, the Toronto and Region Remedial Action Plan (RAP) was formed as a means to set goals and monitor progress around restoring the health of Toronto’s waters, particularly those that feed into Lake Ontario. The most recent progress report [PDF], released this October, highlights immense improvements in the quality of waterways and the species that live there. There have been huge reductions in E.coli counts near the waterfront, resulting in a steady decline of beach closures; the rivers along the waterfront, once thick with a greasy film, now run clear; new and restored habitats for migration, spawning, nursery, feeding and shelter have bolstered species diversity and health in the rivers and the harbour; and fish-eating wildlife are no longer at risk from contaminants.
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I like this idea. The Toronto Star's Allan Woods reports.

For some they mean the beach. For others they mean work. They can be a draw for tourists, but are often just a backdrop for locals.

If you are an environmentalist, you might see them as a living, breathing thing in need of protection, but ask the average high school student and they’ll roll their eyes like they would for any five-point answer on a geography test.

On their own, they are Ontario, Superior, Huron, Erie and Michigan. Together they are the Great Lakes.

You can see them from space, but now a group of prominent Ontarians, helped along by the province’s lieutenant-governor, Elizabeth Dowdeswell, is looking to put them on the map — so to speak — with a campaign to brand the importance of the world’s largest freshwater ecosystem onto peoples’ hearts and minds.

“Why not? The Amazon rainforest is the lungs of the planet. Why can't the Great Lakes be the heart and arteries of North America, or something like that?” said Douglas Wright, who is leading the initiative that will be unveiled next month at the Great Lakes Public Forum in Toronto.

It has been dubbed “Greatness — The Great Lakes Project” and the idea is deceptively simple: create a marketing campaign to embed the lake system deeper into the public consciousness. To get people thinking not only about the environmental threats and challenges, but also about the potential lapping at the shores of communities as diverse as Toronto, Thunder Bay, Toledo and Tobermory.
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  • Bloomberg talks about Poland's problems with economic growth, notes that McMansions are poor investments, considers what to do about the Olympics post-Rio, looks at new Japanese tax incentives for working women, looks at a French war museum that put its stock up for sale, examines the power of the New Zealand dairy, looks at the Yasukuni controversies, and notes Huawei's progress in China.

  • Bloomberg View is hopeful for Brazil, argues demographics are dooming Abenomics, suggests ways for the US to pit Russia versus Iran, looks at Chinese fisheries and the survival of the ocean, notes that high American population growth makes the post-2008 economic recovery relatively less notable, looks at Emperor Akihito's opposition to Japanese remilitarization, and argues that Europe's soft response to terrorism is not a weakness.

  • CBC notes that Russian doping whistleblowers fear for their lives, looks at how New Brunswick farmers are adapting to climate change, and looks at how Neanderthals' lack of facility with tools may have doomed them.

  • The Globe and Mail argues Ontario should imitate Michigan instead of Québec, notes the new Anne of Green Gables series on Netflix, and predicts good things for Tim Horton's in the Philippines.

  • The Guardian notes that Canada's impending deal with the European Union is not any model for the United Kingdom.

  • The Inter Press Service looks at child executions in Iran.

  • MacLean's notes that Great Lakes mayors have joined to challenge a diversion of water from their shared basin.

  • National Geographic looks at the elephant ivory trade, considers the abstract intelligence of birds, considers the Mayan calendar's complexities, and looks at how the young generation treats Pluto's dwarf planet status.

  • The National Post notes that VIA Rail is interested in offering a low-cost bus route along the Highway of Tears in northern British Columbia.

  • Open Democracy notes that the last Russian prisoner in Guantanamo does not want to go home, and wonders why the West ignores the Rwandan dictatorship.

  • TVO considers how rural communities can attract immigrants.

  • Universe Today suggests sending our digital selves to the stars, looks at how cirrus clouds kept early Mars warm and wet, and notes the discovery of an early-forming direct-collapse black hole.

  • Variance Explained looks at how Donald Trump's tweets clearly show two authors at work.

  • The Washignton Post considers what happens when a gay bar becomes a bar with more general appeal.

  • Wired notes that the World Wide Web still is far from achieving its founders' dreams, looks at how news apps are dying off, and reports on the Univision purchase of Gawker.

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The CBC News' Greg Layson reports on the controversy surrounding the idea of allowing the Wisconsin city of Waukesha, just outside of the Great Lakes drainage basin, access to the Great Lakes water. Even with the requirement to return an equivalent among to the Great Lakes, this sets a worrisome trend.

A panel representing governors of the eight states adjoining the Great Lakes unanimously approved a proposal from Waukesha, Wis., which is under a court order to find a solution to radium contamination of its groundwater wells. The city says the project will cost $265 million Cdn for engineering studies, pipelines and other infrastructure.

Waukesha is only 27 kilometres from the lake but just outside the Great Lakes watershed. That required the city of about 72,000 to get special permission under the compact, which prohibits most diversions of water across the watershed boundary.

Paterson immediately took to Twitter to denounce the decision. His peninsula town, the self-proclaimed Tomato Capital of Canada and home to hundreds of greenhouses, is surrounded by Lake Erie.

"This should not be allowed," Paterson told CBC News. "I'm really disappointed it happened. That was unexpected. I actually thought the governor of Michigan was going to side with us. He even bailed."

The Michigan Senate adopted a resolution last month opposing Waukesha's request. Michigan Gov. Rick Snyder went against that and voted in favour of Waukesha's plan Tuesday.
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CBC reports on the proposed Great Lakes diversion. I share the concern of, among others, the government of Ontario.

A suburban Milwaukee city won a hard-fought battle Tuesday to draw its drinking water from Lake Michigan, a key test of a regional compact designed to safeguard the Great Lakes region's abundant but vulnerable fresh water supply.

A panel representing the governors of the eight states adjoining the Great Lakes unanimously approved a $207 million US proposal from Waukesha, Wis., where groundwater wells on which the city has long relied are contaminated with radium.

The city is 24 kilometres from Lake Michigan, but lies just outside the Great Lakes watershed, which required it to get special permission under a 2008 compact that prohibits most diversions of water across the watershed boundary. It provides a potential exception for communities within counties that straddle the line. Waukesha is the first to request water under that provision.

"There are a lot of emotions and politics surrounding this issue but voting yes — in co-operation with our Great Lakes neighbours — is the best way to conserve one of our greatest natural resources," Michigan Gov. Rick Snyder said. "Mandating strict conditions for withdrawing and returning the water sets a strong precedent for protecting the Great Lakes."

The city won a conditional endorsement last month from a panel representing eight states — Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania and Wisconsin — plus Ontario and Quebec. It required Waukesha to reduce the volume of water it would withdraw daily from 37.8 million litres in its application to 31 million litres, and to shrink the size of the area it would provide with Lake Michigan water.
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Roy MacGregor's latest in an installment on river valleys of note in The Globe and Mail takes a look at the Niagara River, a wonder of nature shared by two countries. (I do have to get there, and soon. It is in Toronto's hinterland, after all.)

[T]he falls have moved, a remarkable recession chartered by scientists to have shifted 11 km upstream in the past 12,000 years. Every year, more breaks away, sometimes rock chunks the size of a sixteen-wheeler.

“The shape of the falls is always changing,” says Environment Canada’s Aaron Thompson, who also serves as chair of the International Niagara Board of Control. “The rate has slowed down because so much of the flow goes to the power plants.”

And this, it turns out, is what separates the falls the tourists photograph today from the falls that First Nations knew, which so impressed the likes of Hennepin and Lincoln.

The power of Niagara was such that it created the first great industrial centre of North America. By diverting the water into tunnels leading to turbines, industrialists were able to create electricity, first of all direct-current. Once Nikola Tesla invented alternating-current – a discovery Thomas Edison campaigned against as being too dangerous – it allowed for electricity to travel distances and the great industrialization of the Niagara region spread.

Increasingly, more and more water was diverted into such tunnels. Lord Kelvin, the famous Irish inventor and engineer, said he looked forward to the day when every single drop in the river would be used to create electricity.

Fortunately, wiser heads prevailed. One early suggestion had the power companies ransacking the Niagara as much as they wished six days a week but doing nothing on Sundays so that the tourists could enjoy the falls. That idea, luckily, went nowhere. In 1950, the Niagara Diversion Treaty signed by Canada and the United States specified how much each country could draw for power – roughly half the flow that Hennepin and Lincoln had witnessed.

“They could see that one day there would be no water going over the falls,” Mr. Thompson. says
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The Dragon's Tales linked to this EurekAlert! press release describing a study looking at the temperature of the world's lakes. I mentioned this study before in connection to the Great Lakes, but this is a worldwide trend.

Climate change is rapidly warming lakes around the world, threatening freshwater supplies and ecosystems, according to a study spanning six continents.

The study is the largest of its kind and the first to use a combination of satellite temperature data and long-term ground measurements. A total of 235 lakes, representing more than half of the world's freshwater supply, were monitored for at least 25 years. The research, published in Geophysical Research Letters, was announced today at the American Geophysical Union meeting.

The study, which was funded by NASA and the National Science Foundation, found lakes are warming an average of 0.61 degrees Fahrenheit (0.34 degrees Celsius) each decade. That's greater than the warming rate of either the ocean or the atmosphere, and it can have profound effects, the scientists say.

Algal blooms, which can ultimately rob water of oxygen, are projected to increase 20 percent in lakes over the next century as warming rates increase. Algal blooms that are toxic to fish and animals would increase by 5 percent. If these rates continue, emissions of methane, a greenhouse gas 25 times more powerful than carbon dioxide on 100-year time scales, will increase 4 percent over the next decade.

"Society depends on surface water for the vast majority of human uses," said co-author Stephanie Hampton, director of Washington State University's Center for Environmental Research, Education and Outreach in Pullman. "Not just for drinking water, but manufacturing, for energy production, for irrigation of our crops. Protein from freshwater fish is especially important in the developing world."
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Raveena Aulakh's Toronto Star article shares reasons to fear for the Great Lakes. One day will I be able to swim in Lake Ontario and find myself warmed?

An alarming new study says that freshwater lakes are warming at more than twice the pace of the oceans, and Lake Superior is the second-fastest warming lake studied, behind Sweden’s Lake Fracksjon.

The rest of the Great Lakes are also faring dismally, the study says, putting native fish in jeopardy, increasing the risk of invasive species and raising fears of widespread algae blooms.

The study, by a team of international scientists, analyzed data from hundreds of lakes around the world between 1985 and 2009. It found that summer surface temperatures rose by about 0.34 degrees C per decade on average.

That may not sound like a lot, acknowledged Sapna Sharma, the lead author of the study and an assistant professor in the faculty of science at York University. But put that in context with air temperatures and ocean temperature increase and “you see there is a big difference,” she said.

Average air temperatures over the same period warmed about 0.24 degrees C per decade, while oceans warmed about 0.11 degrees C per decade, she said.
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The loss of the S.S. Edmund Fitzgerald in a storm on Lake Superior occurred 40 years ago today.

On this sad anniversary of tragedy, one that inspired Gordon Lightfoot's song "The Wreck of the Edmund Fitzgerald", the Toronto Star revisited the events.

The waves were over three metres high on Lake Superior early in the morning of Nov. 10, 1975 but that shouldn’t have been too much a problem for the S.S. Edmund Fitzgerald.

The freighter was 220 metres of steel, the largest, fastest, most expensive manmade object ever launched into fresh water.

[. . .]

So Capt. Ernest McSorley, 63, of Toledo, Ohio was concerned but not panicked by the walls of frigid water as he radioed Capt. Jesse Cooper of the S.S. Arthur M. Anderson early that afternoon.

“Anderson, this is the Fitzgerald. I have sustained some topside damage,” McSorley reported. “I have a fence rail laid down, two vents lost or damaged, and a list. I’m checking down. Will you stay by me ’til I get to Whitefish?”

“Charlie on that, Fitzgerald. Do you have your pumps going?”
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Spacing Toronto's Adam Bunch vividly describes an 1813 naval battle in the War of 1812, the last major clash on the Great Lakes.

Just a few months earlier, shipbuilders in Toronto had been hard at work near the foot of Bay Street hammering together the HMS Sir Isaac Brock (named after the British general who died fighting the Americans at Niagara). She was going to be the second biggest ship on Lake Ontario, giving the British control of the water. But there were spies in Toronto — the Americans knew all about the construction. In April, just before the Brock was ready to set sail, the Americans invaded Toronto, hoping to steal the new ship. They won the battle, but the retreating troops burned the Brock before the invading army could get to her.

Still, the advantage on the Great Lakes was swinging dramatically toward the Americans. In early September, they won a stunning victory on Lake Erie. They captured the entire British fleet on that lake, giving them complete control of it. Now, they just needed Lake Ontario: “the key to the Great Lakes.” If they won it, they would be able to pull off their grand plan: ship troops up the St. Lawrence River and besiege Montreal.

So now, the Americans were sailing back toward Toronto. This time, they weren’t coming to capture just one ship; they wanted the entire British fleet.

The man in charge was Commodore Isaac Chauncey. He was from Connecticut, but he first made a name for himself fighting pirates off the coast of Tripoli. Back in April, he’d been in charge of the American ships invading Toronto. Now, he was commanding his fleet from the deck of a brand new flagship: the USS General Pike (named after the American general who’d been blown up at Fort York during the invasion). The Pike sailed at the head of a squadron of ten ships — some towed behind the others for extra firepower. The Americans had bigger guns with longer range than their British counterparts. But their ships were also slower and harder to maneuver.

The British squadron was smaller: just six ships. They were commanded by Commodore Sir James Yeo, an Englishman who had been welcomed to Upper Canada as a hero — one of the rising stars of the most powerful navy on Earth. He sailed aboard his own brand new flagship, the HMS General Wolfe (named after yet another dead general: the guy who had died fighting the French on the Plains of Abraham). She was the sister ship of the burned Brock, built in Kingston at the very same time.
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  • James Bow celebrates his fourth published novel.

  • blogTO celebrates WiFi in Bay station and shares old pictures of the Junction.

  • Speed River Journal's Van Waffle examines the question of what caused new pollution in Lake Erie.

  • Spacing Toronto examines again the controversy over a billboard apparently unauthorized at Bathuest and Davenport.Torontoist links to a project mapping specific songs to specific places on the map of Toronto, observes after Cheri DiNovo turmoil in the post-election Ontario NDP, and notes Dr. Barnardo's Home Children as well as the complex life of possibly-lesbian Mazo de la Roche.

  • Transit Toronto's James Bow approves of Steve Munro's post suggesting that underfunding and neglect will soon cause serious harm to the TTC and its riders.

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  • Discover's Collideascape notes that, even as agricultural land is falling worldwide, the productivity of this land is increasing even more sharply.

  • The Dragon's Gaze links to one paper examining the extent to which saline water might make cooler planets better for live, and to another paper suggesting that planetary magnetic fields are so importance for life (and oxygen levels) that brief reversals in the history of Earth have led to mass extinctions.

  • The Dragon's Tales notes a Ukrainian report that the country's military has captured a Russian tank.

  • Joe. My. God. notes that vehemently anti-gay Minnesota archbishop John Nienstadt is being investigated for allegedly having sexual relationships with men.

  • Marginal Revolution notes that, despite economic collapse, there are some jobs (like low-paying fieldwork) that Portuguese just won't do.

  • The New APPS Blog's Gordon Hull notes the gender inequity involved in the recent Hobby Lobby ruling in the United States.

  • pollotenchegg maps the slow decline of Ukraine's Jewish population in the post-1945 era.

  • Speed River Journal's Van Waffle writes eloquently about his connections to and love of Lake Erie.

  • Strange Maps' Frank Jacobs links to a cartographic examination of the time spent by French television news examining different areas of the world.

  • Towleroad notes a faux apology made by the Israeli education minister after attacking gay families.

  • The Volokh Conspiracy's Jonathan Adler notes the future of contraception coverage under Obamacare.

  • Window on Eurasia reports on fears that Crimean Tatar organizations will soon suffer a Russian crackdown, and suggests that the West should reconsider its policies on Belarus to encourage that country to diversify beyond Russia.

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  • Antipope Charlie Stross wonders if one way to deal with the overaccumulation of wealth by elites is to get them to spend it in vast showy projects, like a crash program for nuclear fusion or a colonization of the upper atmosphere of Venus.

  • Centauri Dreams reacts to the discovery of the nearby and literally ice-cold brown dwarf WISE J085510.83-071442.5.

  • Crooked Timber's Corey Robin argues that a recent American court case regarding a whistleblower highlights a tension between an individual's freedoms as a citizens and limits as a private individual.

  • The Dragon's Gaze links to two papers suggesting that a star's circumstellar habitable zone could expand inwards if a planet is different from Earth, one pointing to slower-rotating planets and the other to lower-mass planets than Earth.

  • The Dragon's Tales reports on the fascinating recovery of evidence of hunting nine thousand years ago from the bottom of Lake Huron.

  • Writing at the Financial Times' The World blog, Edward Luce is worried about Narendra Modi.

  • Language Log comments on browser plug-ins and other like things which adjust text to fit prescriptivist dictates.

  • James Nicoll seems much less impressed than the Volokh Conspiracy's Ilya Somin in the idea of science fiction writers being criticized for their ideologies.

  • The Power and the Money's Noel Maurer argues that a chart suggesting there's a low chance of civil war in Ukraine actually suggests no such thing on closer analysis.

  • Towleroad notes that Russia's anti-gay laws are now being implemented in Crimea.

  • Window on Eurasia's links warn of the need for NATO to defend its own, highlight Belarus' stated interest in a foreign policy that balances the European Union with the Russian sphere, and quotes Crimean Tatar leader Mustafa Cemilev on the Crimean Tatars' continued dissidence and hope for rescue.

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News that Lake Erie, southernmost of the Great Lakes and one upstream from Lake Ontario, is facing environmental catastrophe again as phosphorous runoff feeds algae blooms, featured prominently in this evening's news. See the observation by CBC's Margo McDiarmid.

Lake Erie, once a success story about how a polluted lake can be brought back to life, is once again struggling to survive.

During the summer months, the most southern of the five Great Lakes is smothering under huge blooms of green algae, often thousands of square kilometres in size.

A new report to be released by the International Joint Commission (IJC) this Thursday recommends some immediate steps to save the lake.

The acting Canadian chair of the IJC, Gordon Walker, told the House of Commons environment committee that Lake Erie is in a crisis.

[. . .]

Phosphorus was a problem that many people thought had been solved in the mid-60's.

Canadian researchers discovered that phosphorus in laundry detergent was turning lakes green with algae.

The phosphorous feeds the algae, which absorb the oxygen in the lakes and create dead zones.

In 1972, the U.S. and Canada signed the Great Lakes Water Quality Agreement, which committed them to take action.

That included banning phosphates from all laundry detergent. Within 10 years the levels of phosphorus had dropped and the lakes were on the mend.

But in 2011, a 5,000-square-kilometre algal bloom in Lake Erie was a sign of more trouble. It prompted the IJC to launch a study into the problem.

The report concludes that phosphorus is getting back into Lake Erie from agricultural fertilizers used in growing corn for ethanol and other crops. Domestic lawn fertilizers are also a source of the phosphorus, said Walker.

"Every home wants to have it on their front lawn, he said. "It all runs into the river and it's untreated and that becomes a problem."

The report says rivers in Indiana and Ohio that flow into Lake Erie are the largest sources of phosphorus, but some of it also comes from Ontario's Grand and Thames rivers.
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Reading The Dragon Tales blog, I recently came across some very disturbing news on climate change as it can affect Canada. Glaciers in the Arctic, it turns out, can melt very very quickly with obvious implications for sea level. (Will earlier noted research suggesting that the northeastern coastline of North America will take a particular hit.)

When I learned about this, I congratulated myself for having had the good sense to move from a low-lying island on the northeastern coastline of North America to a city on the shore of the Great Lakes. Alas, my optimism turns out to have rather badly misplaced. This chart, predicting rainfall patterns in North America in the llast two decades of the 21st century, has some implications for Canada. Climate change will be rather uncomfortable in the United States (much more in some areas than others), and it looks like life in Mexico will be seriously harmed, but Canada seems OK. Oh, there is slated to be much more preciptation in winter (Mont-Tremblant survives?), but things are generally unchanged. Except for summer, when precipitation is projected to fall by between 5 and 10%.

Why is this an issue? For this, see this article abstract, the most relevant sections of which I've reposted below.

Eos, Vol. 89, No. 52, 23 December 2008

Dry Climate Disconnected the Laurentian Great Lakes

Recent studies have produced a new understanding of the hydrological history of North America’s Great Lakes, showing that water levels fell several meters below lake basin outlets during an early postglacial dry climate in the Holocene (younger than 10,000 radiocarbon years, or about 11,500 calibrated or calendar years before present (B.P.)). Water levels in the Huron basin, for example, fell more than 20 meters below the basin overflow outlet between about 7900 and 7500 radiocarbon (about 8770–8290 calibrated) years B.P. Outlet rivers, including the Niagara River, presently falling 99 meters from Lake Erie to Lake Ontario (and hence Niagara Falls), ran dry This newly recognized phase of low lake levels in a dry climate provides a case study for evaluating the sensitivity of the Great Lakes to current and future climate change.

[. . .]

Lakes without overflow, such as these lowstands in the GLB, can only be explained by a dry climate in which water lost through evaporation exceeded water gained from direct precipitation and catchment runoff. The dry regional climate that forced the lakes into hydrologic closure must have been substantially drier than the present climate. Hydrologic modeling of the present lakes shows that current mean annual precipitation would have to decrease by about 25% in the Superior basin and by about 42% in the Ontario basin, in conjunction with a 5ºC mean temperature increase, to achieve lake closure [Croley and Lewis, 2006]. Paleoclimate simulations and reconstructions using pollen [Bartlein et al., 1998] and stable isotopes [Edwards et al., 1996] indicate that climate in the GLB (Figure 2c) was drier than present at 7900 radiocarbon (8770 calibrated) years B.P. Termination of the lowstand episode about 7500 radiocarbon (8300 calibrated) years B.P. coincides with the onset of a wetter climate as atmospheric circulation adjusted to the rapidly diminishing ice sheet [Dean et al., 2002] and moist air mass incursions from the Gulf of Mexico became more frequent.

The discovery that the Great Lakes entered a low-level phase without having connecting rivers during the early Holocene dry period demonstrates the sensitivity of the lakes to climate change. The closed lakes of this phase occurred when the Great Lakes entered their present nonglacial state. Thus, the closed lakes afford a valuable example of past, high-amplitude, climate-driven hydrologic variation upon which an improved assessment of lake-level sensitivity in response to future climates can be based.

A common joke is that although Toronto's located on the shores of Lake Ontario its inhabitants certainly don't have much of a sense of having a waterfront. In a century's time, if the charts referred to above underestimate the situation, might it be that Toronto will be an inland city in faact as well as in sentiment?


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