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Great Lakes

2007 Schools Wikipedia Selection. Related subjects: General Geography

   The Great Lakes from space
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   The Great Lakes from space

   The Great Lakes are a group of five large lakes in North America on or
   near the Canada-United States border. They are the largest group of
   fresh water lakes on Earth. The Great Lakes- St. Lawrence system is the
   largest fresh-water system in the world. They are sometimes referred to
   as inland seas.

Lakes

   Lake Superior
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   Lake Superior
   Lake Michigan
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   Lake Michigan
   Lake Huron
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   Lake Huron
   Lake Erie
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   Lake Erie
   Lake Ontario
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   Lake Ontario

   Great Lakes: System Profile
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   Great Lakes: System Profile

   The Great Lakes are:
     * Lake Superior (the largest by volume and deepest, larger than
       Scotland or South Carolina)
     * Lake Michigan (the second-largest by volume and third-largest by
       area; the only one entirely in the U.S.)
     * Lake Huron (the third-largest by volume; the second largest in
       area)
     * Lake Erie (the smallest by volume and shallowest)
     * Lake Ontario (the second-smallest in volume and smallest in area,
       much lower elevation than the rest)

   Map of the Great Lakes/St. Lawrence Watershed
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   Map of the Great Lakes/St. Lawrence Watershed

   Lakes Michigan and Huron, being hydrologically intertwined, are
   sometimes considered to be one entity: Lake Michigan-Huron. Considered
   together, Michigan-Huron would be larger in surface area than Lake
   Superior, but smaller in total water volume.

   A much smaller sixth lake, Lake St. Clair, is part of the Great Lakes
   system between Lake Huron and Lake Erie, but is not considered one of
   the "Great Lakes." The system also includes the rivers that connect the
   lakes: St. Marys River between Lake Superior and Lake Huron, the St.
   Clair River between Lake Huron and Lake St. Clair, the Detroit River
   between Lake St. Clair and Lake Erie, and the Niagara River and Niagara
   Falls, between Lake Erie and Lake Ontario. (Lake Michigan is connected
   to Lake Huron through the Straits of Mackinac.) Large islands and a
   peninsula divides Lake Huron into the lake proper and Georgian Bay.

   The lakes are bounded by Ontario (all of the lakes but Michigan),
   Minnesota, Wisconsin, Michigan (all but Ontario), Illinois, Indiana,
   Ohio, Pennsylvania, and New York. Four of the five lakes straddle the
   U.S.-Canada border; the fifth, Lake Michigan, is entirely within the
   United States. The Saint Lawrence River, which marks the same
   international border for a portion of its course, is a primary outlet
   of these interconnected lakes, and flows through Quebec and past the
   Gaspé Peninsula to the northern Atlantic Ocean.
   The Great Lakes are clearly visible in this satellite image of North
   America
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   The Great Lakes are clearly visible in this satellite image of North
   America

   Sprinkled throughout the lakes are the approximately 35,000 Great Lakes
   islands, including Manitoulin Island in Lake Huron, the largest island
   in any inland body of water, and Isle Royale in Lake Superior, the
   largest island in the largest lake (each island large enough to itself
   contain multiple lakes).

   Today, 20 percent of the world’s fresh surface water is contained in
   the five great lakes: 5,473 cubic miles (22,812 km³), or 6 quadrillion
   gallons (22.81 quadrillion litres) in all. It is enough water to cover
   the contiguous 48 states to a uniform depth of 9.5 feet (2.9 m). The
   combined surface area of the lakes is 94,250 square miles
   (244,100 km²)— larger than the states of New York, New Jersey,
   Connecticut, Rhode Island, Massachusetts, Vermont and New Hampshire
   combined.

   The Saint Lawrence Seaway and Great Lakes Waterway opened the Great
   Lakes to ocean-going vessels. However the move to wider ocean-going
   container ships - which do not fit through the locks on these routes -
   has limited shipping on the lakes. Despite their vast size, large
   sections of the Great Lakes freeze over in winter, and most shipping
   stops during that season. There are some icebreakers that operate on
   the lakes.

   The lakes have an effect on weather in the region, known as lake
   effect. In winter, the moisture picked up by the prevailing winds from
   the west can produce very heavy snowfall, especially along lakeshores
   to the east such as Indiana, Michigan, Ontario, and New York. It is not
   uncommon for heavy snow to occur during completely clear skies because
   of this phenomenon. The lakes also moderate seasonal temperatures
   somewhat, by absorbing heat and cooling the air in summer, then slowly
   radiating that heat in autumn. This temperature buffering produces
   areas known as "fruit belts", where fruit typically grown farther south
   can be produced in commercial quantities.

   CAPTION: Relative elevations, average depths, maximum depths, and
   volumes of the Great Lakes.

   [USEMAP:29274.png]
    Notes: The area of each rectangle is proportionate to the volume of
           each lake. All measurements at Low Water Datum.
   Source: EPA's Great Lakes Atlas: Factsheet #1.

Geologic pre-history

   The Great Lakes were formed at the end of the last ice age about 10,000
   years ago, when the Laurentide ice sheet receded. When this happened,
   the glaciers left behind a large amount of meltwater (see Lake Agassiz)
   which filled up the basins that the glaciers had carved, thus creating
   the Great Lakes as we know them today. Because of the uneven nature of
   glacier erosion, some higher hills became Great Lakes islands. The
   Niagara Escarpment follows the contour of the Great Lakes between New
   York and Wisconsin -- Herbert Simon called this escarpment the spinal
   cord of my native land.

Economy

   The lakes are extensively used for transport, though cargo traffic has
   decreased considerably in recent years. The Great Lakes Waterway makes
   each of the lakes accessible.

   During settlement, the Great Lakes and its rivers were the only
   practical means of moving people and freight. Anything and everything
   floated on the lakes. Some ended up on the bottom because of storms,
   fires, collisions and underwater hazards. (See Edmund Fitzgerald and Le
   Griffon.) Barges from middle North America were able to reach the
   Atlantic Ocean from the Great Lakes when the Erie Canal opened in 1825.
   By 1848, with the opening of the Illinois and Michigan Canal at
   Chicago, direct access to the Mississippi River was possible from the
   lakes. With these two canals an all-inland water route was provided
   between New York City and New Orleans.

   The main business of many of the passenger lines in the 1800s was
   transporting immigrants. Many of the larger cities owe their existence
   to their position on the lakes as a freight destination as well as for
   being a magnet for immigrants. After railroads and surface roads
   developed the freight and passenger businesses dwindled and, excepting
   ferries and a few foreign cruise ships, now has vanished.

   Yet, the immigration routes still have an effect today. Immigrants
   often formed their own communities and some areas have a pronounced
   ethnicity, such as Dutch, German, Polish, Finnish, and many others.
   Since many immigrants settled for a time in New England before moving
   westward, many areas on the U.S. side of the Great Lakes also have a
   New England feel, especially in home styles and accent.

   Since general freight these days is transported by railroads and trucks
   (lorries), domestic ships mostly move bulk cargoes, such as iron ore
   and its derivatives, coal and limestone for the steel industry. The
   domestic bulk freight developed because of the nearby mines. It was
   more economical to transport the ingredients for steel to centralized
   plants rather than try to make steel on the spot. Ingredients for
   steel, however, are not the only bulk shipments made. Grain exports are
   also a major shipping commodity on the lakes.

   In the 19th and early 20th centuries, iron and other ores such as
   copper were shipped south on (downbound ships) and supplies, food
   staples, and coal was shipped north (upbound). Because of the location
   of the coal fields in Pennsylvania and West Virginia, and the general
   northeast track of the Appalachian Mountains, railroads naturally
   developed shipping routes that went due north to ports such as Erie,
   Pennsylvania and Ashtabula, Ohio.

   Because the lake maritime community largely developed independently, it
   has its own language. Ships, no matter the size, are referred to as
   boats. When the sailing ships gave way to steamships, they were called
   steamboats—the same term used on the Mississippi. The ships also have a
   distinctive design. Ships that primarily trade on the lakes are known
   as lakers. Foreign boats are known as salties.

   One of the more common sights on the lakes is the 1,000 by 105-foot
   (305 by 32-m), 60,000 U.S. long tons (61,000 metric tonnes)
   self-unloader. This is a laker with a huge conveyor belt system that
   can unload itself by swinging a crane over the side. Today, the Great
   Lakes fleet is much smaller in numbers than it once was because of the
   increase use of overland freight and the use of larger ships replacing
   the need for many smaller ships.

Modern economy

   The Great Lakes are used as a major mode of transport for bulk goods.
   The brigantine Le Griffon, which was commissioned by René Robert
   Cavelier, Sieur de La Salle, was built at Cayuga Creek, near the
   southern end of the Niagara River, to become the first sailing ship to
   travel the upper Great Lakes on August 7, 1679.

   In 2002, 162 million net tons of dry bulk cargo was moved on the Lakes.
   This was, in order of volume: iron ore, coal, stone, grain, salt,
   cement and potash. The iron ore and much of the stone and coal are used
   in the steel industry. There is also some shipping of liquid and
   containerized cargo but most container ships cannot pass the locks on
   the Saint Lawrence Seaway because they are too wide. The total amount
   of shipping on the lakes has been on a downward trend for several
   years.
   Wolfe Islander III, Kingston, Ontario
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   Wolfe Islander III, Kingston, Ontario

   Recreational boating and tourism are major industries on the Great
   Lakes. A few small cruise ships operate on the Great Lakes including a
   couple of sailing ships. Sport fishing, commercial fishing, and Native
   American fishing represent a US$4 billion a year industry with salmon,
   whitefish, smelt, lake trout, and walleye being major catches.

   The Great Lakes are used to supply drinking water to tens of millions
   of people in bordering areas. This valuable resource is collectively
   administered by the state and provincial governments adjacent to the
   lakes.

Passenger traffic

   Several ferries operate on the Great Lakes to carry passengers to
   various islands, including Isle Royale, Pelee Island, Mackinac Island,
   Beaver Island, both Bois Blanc Islands, Kelleys Island, South Bass
   Island, North Manitou Island, South Manitou Island, Harsens Island,
   Manitoulin Island, and the Toronto Islands. As of 2005, three car ferry
   services cross the Great Lakes: a steamer across Lake Michigan from
   Ludington, Michigan to Manitowoc, Wisconsin; a high speed catamaran on
   a second Lake Michigan route from Milwaukee to Muskegon, Michigan. An
   international ferry across Lake Ontario from Rochester, New York to
   Toronto ran during the summer of 2004, but is no longer in operation.

Shipwrecks

   Travel on the Lakes has not been without risks. There are parts where
   no land is visible because of the immense size of the Lakes: thus they
   are sometimes referred to as inland seas.

   Storms and reefs are a common threat, and many thousands of ships have
   sunk in these waters. It is estimated that between 6,000 and 10,000
   ships have sunk or been stranded since the early 1800s, many with
   partial or total loss of crew. This area is prone to sudden and severe
   storms, particularly in the autumn from late October until early
   December. The Great Lakes Storm of 1913 became the worst Great Lakes
   storm on record: at least 12 ships sank, and 31 more were stranded on
   rocks and beaches. At least 248 sailors lost their lives over that
   weekend. The SS Edmund Fitzgerald, which sank November 10, 1975, was
   famously the last major freighter lost on the lakes. For many years in
   the late 1700s and early 1800s, wars were fought over the control of
   the Lakes and many warships were built for the inland seas, ranging
   from small and swift sloops-of-war to three-deckers capable of standing
   in any line of battle. USS Freedom (LCS-1) is the newest warship to be
   built on the Great Lakes. The Rush-Bagot Agreement of 1817 limits the
   number of armed vessels permitted on the Great Lakes.

   The greatest concentration of these wrecks lies near Thunder Bay
   (Michigan), beneath Lake Huron, near the point where eastbound and
   westbound shipping lanes converge. Today there is a U.S. NOAA Marine
   Archeology Research Station located in the Thunder Bay National Marine
   Sanctuary. Here divers can explore more than 200 shipwrecks that form
   one of the most concentrated and best preserved maritime archaeology
   sites in the world.

Invasive species

   The Great Lakes have been hit economically by various invasive species,
   namely the sea lamprey, Quagga mussel, and zebra mussel. The mussels
   clog pipes leading to the lakes and causes approximately US$1 billion
   in damages per year while destroying native species. The lamprey feeds
   on the sport fish of the lakes, making them less attractive to
   fishermen. An electric fence has been set up across the mouth of the
   Great Lakes in order to keep an invasive species of Asian carp out of
   the area.

Political issues

Great Lakes Water Use and Diversions

   The International Joint Commission was established in 1909 to help
   prevent and resolve disputes relating to the use and quality of
   boundary waters, and to advise Canada and the United States on
   questions related to water resources. Concerns over diversion of Lake
   water are of concern to both Americans and Canadians. Some water is
   diverted through the Chicago River to operate the Illinois Waterway but
   the flow is limited by treaty. Possible schemes for bottled water
   plants and diversion to dry regions of the continent raise concerns.
   Under the U.S. "Water Resources Development Act" , diversion of water
   from the Great Lakes basin requires the approval of all eight Great
   Lakes governors, which rarely occurs. International treaties regulate
   large diversions. In 1998, the Canadian company Nova Group won approval
   from the Province of Ontario to withdraw 158,000,000 US gallons
   (600,000 m³) of Lake Superior water annually to ship by tanker to Asian
   countries. Public outcry forced the company to abandon the plan before
   it began. Since that time, the eight Great Lakes Governors and the
   Premiers of Ontario and Quebec have negotiated the Great Lakes-St.
   Lawrence River Basin Sustainable Water Resources Agreement and the
   Great Lakes-St. Lawrence River Basin Water Resources Compact that would
   prevent most future diversion proposals and all long-distance ones. The
   agreements also strengthen protection against abusive water withdrawal
   practices within the Great Lakes basin. On December 13, 2005, The
   Governors and Premiers signed these two agreements: the first is
   between all ten jurisdictions. It is somewhat more detailed and
   protective, but cannot be enforced in court because enforcement
   arrangements can be made only between the federal governments. The
   second is just between the U.S. states, which, if approved by all eight
   state legislatures which border the Great Lakes and the U.S. Congress,
   could be enforced in U.S. federal court.

Coast Guard Live Fire Exercises on the Great Lakes

   In August of 2006 the United States Coast Guard published a notice in
   the Federal Register that they intended to designate 34 areas in U.S.
   portions of the Great Lakes at least five miles offshore as permanent
   safety zones for live fire machine gun practice. Each zone would be
   used by the Coast Guard for a maximum total of 24 hours a year and
   would be open to the public when not in use. In response to requests
   from the public, the Coast Guard is holding a series of public meetings
   in nine U.S. cities to solicit comment. The vast majority of people who
   showed up to voice concern about the plan and its impact on the
   environment. Several environmental organizations and government
   officials have voiced their opposition. A preliminary health risk
   assessment stated that the “proposed training will result in no
   elevated risks for a freshwater system such as the Great Lakes… or
   generic marine environments using ‘realistic worst case’ assumptions,
   and further investigation is not recommended. If typical rather than
   worst case assumptions were used the predicted risk would be even
   less.” The Coast Guard has established an information page about their
   proposal.

Restoration

   In the U.S. Congress, the Great Lakes Collaboration Implementation Act
   puts into practice priority recommendations of a $20 billion Great
   Lakes clean-up plan released in December as part of the Great Lakes
   Regional Collaboration , a planning process established by President
   Bush in 2004. A bipartisan group of U.S. legislators introduced the
   bill, including U.S. Sens. Mike DeWine (R-Ohio) and Carl Levin
   (D-Michigan) and Reps. Vern Ehlers (R-Grand Rapids) and Rahm Emanuel
   (D-Chicago). The Great Lakes Collaboration Implementation Act would:

   •Stop the introduction and spread of aquatic invasive species by
   enacting a comprehensive national program. •Prevent the Asian carp from
   entering the Great Lakes by authorizing the Corps of Engineers to
   maintain and operate the dispersal barrier on the Chicago Sanitary and
   Ship Canal, and prohibit the importation and sale of Asian carp.
   •Restore fish and wildlife habitat by reauthorizing the Great Lakes
   Fish & Wildlife Restoration Act at $20 million. •Prevent sewage
   contamination by reauthorizing the State Revolving Loan Fund and
   provide $20 billion over five years to assist communities nationally
   with improving their wastewater infrastructure. •Clean up contaminated
   sediment under the Great Lakes Legacy Act by authorizing $150 million
   per year. •Phase out mercury in products by establishing a new grant
   program and improving existing research programs. •Coordinate and
   improve Great Lakes programs by establishing the Great Lakes
   Interagency Task Force and the Great Lakes Regional Collaboration
   process.

   The Healing Our Waters(R) - Great Lakes Coalition has formed to help
   groups and citizens across the United States advocate for restoring the
   health of the Great Lakes.

Additions to the Five Great Lakes

   Lake Champlain on the border between upstate New York and northwestern
   Vermont briefly became labelled by the U.S. government as the sixth
   "Great Lake of the United States" on March 6, 1998, when President
   Clinton signed Senate Bill 927. This bill, which reauthorized the
   National Sea Grant Program, contained a line penned by Senator Patrick
   Leahy (D-VT) declaring Lake Champlain to be a Great Lake. Not
   coincidentally, this status allows neighboring states to apply for
   additional federal research and education funds allocated to these
   national resources. The claim was viewed with some amusement by other
   countries, particularly in the Canadian media as many Canadians were
   originally unfamiliar with the lake's existence (despite its role in
   the War of 1812) and the lake is small compared to other Canadian lakes
   (such as Great Bear Lake which has over 27x more surface area).
   Following a small uproar (and several New York Times articles), the
   Great Lake status was rescinded on March 24 (although Vermont
   universities continue to receive funds to monitor and study the lake).

   Similarly, there has been interest in making Lake St. Clair a Great
   Lake. In October, 2002, backers planned to present such a proposal at
   the Great Lakes Commission annual meeting, but ultimately withheld it
   as it appeared to them to have too little support.

Ecological challenges

   Before the arrival of Europeans, the lakes provided fish to the native
   groups who lived near them. Early European settlers were astounded by
   both the variety and quantity of fish. Historically, fish populations
   were the early indicator of the condition of the Lakes, and have
   remained one of the key indicators even in our technological era of
   sophisticated analyses and measuring instruments. According to the
   bi-national (U.S. and Canadian) resource book, The Great Lakes: An
   Environmental Atlas and Resource Book, "the largest Great Lakes fish
   harvests were recorded in 1889 and 1899 at some 67,000 tonnes (147
   million pounds)," though the beginning of environmental impacts on the
   fish can be traced back nearly a century prior to those years.

   By 1801, New York legislators found it necessary to pass regulations
   curtailing obstructions to the natural migrations of Atlantic salmon
   from Lake Erie into their spawning channels. In the early nineteenth
   century, Upper Canada’s government found it necessary to introduce
   similar legislation prohibiting the use of weirs and nets at the mouths
   of Lake Ontario’s tributaries. Other protective legislation was passed
   as well, but enforcement remained difficult and often quite spotty.

   On both sides of the U.S.-Canada border, the proliferation of dams and
   impoundments multiplied, necessitating more regulatory efforts. The
   decline in fish populations was unmistakable by the middle of the
   nineteenth century. The decline in salmon was recognized by Canadian
   officials and reported as virtually a complete absence by the end of
   the 1860s. The Wisconsin Fisheries Commission noted a reduction of
   roughly 25 percent in general fish harvests by 1875.

   Overfishing was cited as responsible for the decline of the population
   of various whitefish, important because of their culinary desirability
   and, hence, economic consequence. Moreover, between 1879 and 1899,
   reported whitefish harvests declined from some 24.3 million pounds (11
   million kg) to just over 9 million pounds (4 million kg). Recorded
   sturgeon catches fell from 7.8 million pounds (1.5 million kg) in 1879
   to 1.7 million pounds (770,000 kg) in 1899.

   There were, however, other factors in the declines besides overfishing
   and the problems posed by dams and other obstructions. Logging in the
   region removed tree cover near stream channels which provide spawning
   grounds, and this affected necessary shade and temperature-moderating
   conditions. Removal of tree cover also destabilized soil, allowing soil
   to be carried in greater quantity into the streambeds, and even brought
   about more frequent flooding. Running cut logs down the Lakes’
   tributary rivers also stirred bottom sediments. In 1884, the New York
   Fish Commission determined that the dumping of sawmill waste (chips and
   sawdust) was impacting fish populations.

   The Great Lakes are international, and in situations that require
   regulation, a lack of cooperation between the U.S. and Canada might be
   predicted to have disastrous consequences. In the development of
   ecological problems in the Great Lakes, it was the influx of parasitic
   lamprey populations after the development of the Erie Canal and the
   much later Welland Canal that led to the two federal governments
   attempting to work together – which proved a very complicated and
   troubled road.

   Nevertheless, despite the ever more sophisticated efforts to eliminate
   or minimize the lamprey, by the mid 1950s Lake Michigan and Huron’s
   lake trout populations were reduced by about 99%, with the lamprey
   deemed largely to blame. A result was the bi-national Great Lakes
   Fishery Commission.

   Other ecological problems in the Lakes and their surroundings have
   stemmed from urban sprawl, sewage disposal, and toxic industrial
   effluent. These, of course, also affect aquatic food chains and fish
   populations. Some of these glaring problem areas are what attracted the
   high-level publicity of Great Lakes ecological troubles in the 1960s
   and 1970s. Evidence of chemical pollution in the Lakes and their
   tributaries now stretches back for decades. In the late 1960s, the
   recurrent phenomenon of the surface of river stretches (see Ohio’s
   Cuyahoga River) catching fire from a combination of oil, chemicals, and
   combustible materials floating on the water’s surface, came to the
   attention of a public growing more environmentally aware. Another
   aspect that caught popular attention was the “toxic blobs” (expanses of
   lake bed covered by various combinations of such substances as
   solvents, wood preservatives, coal tar, and metals) found in Lake
   Superior, the St. Clair River, and other portions of the Great Lakes
   region.

   According to the authoritative bi-national source The Great Lakes: An
   Environmental Atlas and Resource Book, "Only pockets remain of the once
   large commercial fishery."

   The annual Great Lakes Bioneers Conference held in Traverse City,
   Michigan addresses many of these problems with local speakers,
   workshops and tools. The conference is a satellite conference of the
   Bioneer Conference in San Rafael, California. The Traverse City site
   focuses on durable ecological and socially just solutions to a diverse
   set of issues in the Great Lakes bioregion.

Trivia

   The names of the five Great Lakes are often remembered with the
   mnemonic HOMES, from the first letter of the name of each lake.

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