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56-539: The river's source is at the confluence of the West Branch Mohawk River and East Branch Mohawk River in north-central Oneida County . It begins flowing generally southeastward towards the Hamlet of Hillside, first receiving Blue Brook then McMullen Brook and Haynes Brook . In Hillside is the confluence of Lansing Kill , after which it flows towards the Hamlet of North Western receiving Stringer Brook along

112-558: A drastic negative impact on the global extent and stability of the cryosphere. On the millennial time scales of Pleistocene glacial and interglacial cycles, the pacemaker of glaciation onset and melting are changes in orbital parameters termed the Milankovitch cycles . Specifically, low summer insolation in the northern hemisphere permits growth of ice sheets, while high summer insolation causes more ablation than winter snow accumulation. Human activities promoting climate change , notably

168-610: A large enough scale, an increase in volcanic activity provides a positive feedback to the process of deglaciation as a result CO 2 and methane released from volcanos. Periods of deglaciation are also caused in part by oceanic processes. For example, interruptions of the usual deep cold water circulation and penetration depths in the North Atlantic have feedbacks that promote further glacial retreat. Deglaciation influences sea level because water previously held on land in solid form turns into liquid water and eventually drains into

224-452: A long record of significant and damaging floods along the entire length of the river. Because the river and its tributaries typically freeze in the winter, the spring melt is commonly accompanied by ice floes that get stuck and jammed along the main trunk of the river. This annual spring breakup typically occurs in the last few weeks of March, although there are numerous floods that have occurred before or after this time, such as in 2018 when

280-682: A mountain" (or Yeionontatátie , "going round a mountain"). The first recorded European exploration of the Mohawk was a trip by the Dutchman Harman Meyndertsz van den Bogaert in 1634. He followed the river upstream from Albany for a distance of 100 miles, including all the territory of the Mohawks. In 1661 Dutch colonists founded the city of Schenectady on the Mohawk River approximately 19 miles (31 km) from Albany. "For fifty years Schenectady

336-553: A project to improve the flood walls on South Chuctanunda Creek and Mohawk River. The floodwalls and river banks were repaired at a cost of $ 164,248. Historically, the Mohawk watershed has lacked a watershed management plan typical in many adjacent basins. In 2010, the New York State Department of Environmental Conservation released the Mohawk River Basin Action Agenda, which is the first framework for

392-506: A result of all of this, the world's main ice sheets, including the ones located in Eurasia, North America and parts of the Antarctic melted. As a consequence, sea levels rose roughly 120 metres. These processes did not occur steadily, and they also did not occur at the same time. The process of deglaciation reflects a lack of balance between existing glacial extent and climatic conditions. As

448-468: A result of net negative mass balance over time, glaciers and ice sheets retreat. The repeated periods of increased and decreased extent of the global cryosphere (as deduced from observations of ice and rock cores, surface landforms, sub-surface geologic structures, the fossil record, and other methods of dating) reflect the cyclical nature of global and regional glaciology measured by ice ages and smaller periods known as glacials and interglacials . Since

504-613: A thin sequence of Devonian limestones that are overlain by a thick sequence of sandstones and shale of the Catskill Delta , which is also Devonian in age. During the Pleistocene (c. 1.8 to 0.01 mya ), the watershed was extensively modified by continental glaciation . As a result of glacial scour and deposition, the surficial deposits in much of the watershed are poorly sorted boulder- and clay-rich glacial till . During deglaciation , several glacial lakes left varved clay deposits. In

560-620: A watershed management plan in this basin. This plan identifies five priority goals for the Mohawk River Basin that are designed to enhance ecosystem health and the vitality of the region. The Action Agenda, developed by the NYS DEC in collaboration with a number of stakeholders in the basin with public input, advocates an ecosystem-based approach to watershed management. In October 2014, Riverkeeper, an environmental advocacy and clean water watchdog organization, announced that they will be expanding

616-407: A week. There was considerable damage everywhere, especially Mohawk and Fort Plain. On July 3, 1985, Congress approved a project at Amsterdam for work to be done on the Mohawk River and South Chuctanunda Creek. South Chuctanunda Creek was cleared at the upstream end of the project for approximately 950 feet (290 m). New flood walls were installed along the right bank of South Chuctanunda Creek and

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672-482: Is a stub . You can help Misplaced Pages by expanding it . Deglaciation Deglaciation is the transition from full glacial conditions during ice ages , to warm interglacials , characterized by global warming and sea level rise due to change in continental ice volume. Thus, it refers to the retreat of a glacier , an ice sheet or frozen surface layer, and the resulting exposure of the Earth 's surface. The decline of

728-667: The Great Lakes at Buffalo, New York . The lower part of the Mohawk River has five permanent dams , nine movable dams (seasonal), and five active hydropower plants . Schoharie Creek and West Canada Creek are the principal tributaries of the Mohawk River. Both of these tributaries have several significant dams including the Hinckley Dam on the West Canada and the Gilboa Dam on the upper reaches of Schoharie Creek. The Gilboa Dam, which

784-741: The Green Mountains of Vermont ; and westward to the border with the Iroquoian Oneida Nation 's traditional homeland territory. The river has long been important to transportation and migration to the west as a passage through the Appalachian Mountains , between the Catskill Mountains and Allegheny Plateau to the south and the Adirondack Mountains to the north. The Mohawk Valley allowed easier passage than going over

840-582: The Laurentide Ice Sheet spread over large areas of northern North America, with over 5,000,000 square miles of coverage. The Laurentide ice sheet was 10,000 feet deep in some areas, and reached as far south as 37°N. Mapped extent of the Laurentide Ice Sheet during deglaciation has been prepared by Dyke et al. Cycles of deglaciation are driven by various factors, with the main driver being changes in incoming summer solar radiation, or insolation, in

896-644: The Southern Ocean contain long-sequestered stores of CO 2 which are now being emitted into the atmosphere and are continuing to impact glacial dynamics. The principle of isostasy applies directly to the process of deglaciation, especially post-glacial rebound , which is one of main mechanisms through which isostasy is observed and studied. Post-glacial rebound refers to the increase in tectonic uplift activity immediately following glacial retreat. Increased rates and abundance of volcanic activity have been found in regions experiencing post-glacial rebound. If on

952-600: The cryosphere due to ablation can occur on any scale from global to localized to a particular glacier. After the Last Glacial Maximum (ca. 21,000 years ago), the last deglaciation begun, which lasted until the early Holocene . Around much of Earth, deglaciation during the last 100 years has been accelerating as a result of climate change , partly brought on by anthropogenic changes to greenhouse gases . The previous deglaciation took place from approximately 22  ka until 11.5 ka. This occurred when there

1008-606: The LGM compared to today, as there was open forest, where today we see desert and steppe. In the United States, the general variation of vegetation implies an overall fall in temperatures of (at minimum 5 °C), a shift of the westerly storm tracks to the south, and a very steep latitudinal temperature gradient. Several landforms visible today are distinctive of the powerful erosional forces at play during, or immediately after, deglaciation. The distribution of such landforms helps to inform

1064-461: The Laurentide ice sheet presented a positive surface mass balance during almost the entirety of its deglaciation, which indicates that the loss of mass throughout its deglaciation was more than likely due to dynamic discharge. It was not until the early Holocene when the surface mass balance switched to become negative. This change to a negative surface mass balance suggested that surface ablation became

1120-535: The Mohawk Barge Canal locks sustained major damage, especially near Waterford and Rotterdam Junction. Another major flood was on June 28, 2013. It was caused by heavy rain that had fallen in the region for weeks. On the night of June 27, 2013, the Jordanville area reported that 4 inches of rain fell in one hour. The next day, the Mohawk River flooded the valley, residents were stranded and without power for about

1176-602: The Mohawk River. A new wing wall was installed on the left bank of South Chuctanunda Creek at the upstream end of the New York Central Railroad Bridge. The South Chuctanunda was realigned and reshaped for approximately 1,056 feet (322 m) and riprap was added where needed. The existing channel of the South Chuctanunda was slightly reshaped downstream of the Florida Avenue bridge. Construction plans for

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1232-434: The Mohawk, Delaware , and Susquehanna watersheds. Across the state, this event caused over $ 227 million in damage and resulted in the loss of four lives. This flooding was acute in the upper parts of the Mohawk watershed. The Mohawk River also saw significant flooding during the weeks between August 21, 2011, and September 5, 2011, due to torrential rains experienced from Hurricane Irene and Tropical Storm Lee . Many of

1288-487: The NY State Legislature in 1997 to improve historic preservation along the river. The Mohawk River has a relatively long record of flooding that has been documented back to settlement in the 17th century. The average volume of water that flows through the Mohawk is about 184 billion cubic feet (5.21 km) every year. Much of the water flows through the watershed in the spring as snow melts rapidly and enters

1344-655: The Northern Hemisphere. But, as not all of the rises in insolation throughout time caused deglaciation, to the current ice volumes that we witness today. This leads to a different conclusion, one that suggests that there is a possible climatic threshold, in terms of ice sheets retreating, and eventually disappearing. As Laurentide was the largest mass ice sheet in the Northern Hemisphere, much study has been conducted regarding its disappearance, unloading energy balance models, atmosphere-ocean general circulation models, and surface energy balance models. These studies concluded that

1400-796: The Scotia Delta, which is also known as the Great Flats Aquifer. The river is named for the Mohawk Nation of the Iroquois Confederacy . In the 1700s and before, the Mohawk people, a section of Iroquois Confederacy , were based in the Mohawk Valley , which included the area around the creek. Their territory ranged north to the St. Lawrence River , southern Quebec and eastern Ontario ; south to greater New Jersey and into Pennsylvania; eastward to

1456-418: The alteration of ice sheets, to the concentration of greenhouse gases fluctuating, and many other feedbacks that resulted in distinct responses, both globally and regionally. Not only were ice sheets and greenhouse gases experiencing alteration, but also additionally to this, there was sudden climate change , and many occurrences of fast, and sizeable rising of sea level. The melting of the ice sheets, along with

1512-513: The condition of snow and ice on Earth's surface. In colder periods massive ice sheets may extend toward the Equator , while in periods warmer than today, the Earth may be completely free of ice. A significant, empirically demonstrated, positive relationship exists between the surface temperature and concentration of Greenhouse gases such as CO 2 in the atmosphere . The higher concentration, in turn, has

1568-466: The difficulties of European westward settler migration . The Mohawk Valley still plays an important role in transportation. Railroads followed the Water Level Route , as did major east–west roads such as Route 5 and Interstate 90 . The Mohawk River Heritage Corridor Commission was created to preserve and promote the natural and historic assets of the Mohawk River. This commission was created by

1624-478: The driver that resulted in the loss of mass of ice in the Laurentide ice sheet. It is concluded then that the Laurentide ice sheet only began to exhibit behaviours and patterns of deglaciation after radiative forcing and summer temperatures began to rise at the beginning of the Holocene. When the Laurentide ice sheet progressed through the process of deglaciation, it created many new landforms and had various effects of

1680-403: The east was populated by cold-tolerant conifer forests, while the southeast and northwest of the United States sustained open forests in locations that have closed forests today, which suggests that during the LGM temperatures were cooler and overall conditions were much drier than those that we experience today. There is also indication that the southwest of the United States was much wetter during

1736-540: The end of the Last Glacial Maximum to the early Holocene (ca. 19k-11k years ago), shows changes in greenhouse gas concentrations and of the Atlantic meridional overturning circulation (AMOC), when sea-level rose by 80 meters. Additionally, the last deglaciation is marked by three abrupt CO 2 pulses, and records of volcanic eruptions show that subaerial volcanism increased globally by two to six times above background levels between 12 ka and 7 ka. Between roughly 19ka,

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1792-509: The end of the Last glacial period about 12,000 years ago, ice sheets have retreated on a global scale, and Earth has been experiencing a relatively warm interglacial period marked by only high-altitude alpine glaciers at most latitudes with larger ice sheet and sea ice at the poles. However, since the onset of the Industrial Revolution , human activity has contributed to a rapid increase in

1848-469: The end of the Last Glacial Maximum (or LGM) to 11ka, which was the early Holocene, the climate system experienced drastic transformation. Much of this change was occurring at an astonishing rate, as the earth was dealing with the end of the last ice age. Changes in insolation was the principal reason for this drastic global change in climate, as this was linked with several other changes globally, from

1904-507: The extensive use of fossil fuels over the last 150 years and the resulting increase in atmospheric CO 2 concentrations, are the principal cause of the more rapid retreat of alpine glaciers and continental ice sheets all across the world. For example, the West Antarctic Ice Sheet has receded significantly, and is now contributing to a positive feedback loop that threatens further deglaciation or collapse. Newly exposed areas of

1960-479: The final stages of deglaciation, approximately 13,350 years ago, the catastrophic draining of Glacial Lake Iroquois , a pro-glacial lake, was through what would become the modern Mohawk Valley. In this final phase, the enormous discharge of water caused local deep scour features (e.g. the Potholes at Little Falls ), and extensive sand and gravel deposition, which is one of the key sources of municipal groundwater including

2016-528: The greatest density, and most salt content during the LGM. The discharge of such sequestered carbon was perhaps a direct outcome of the deep Southern Ocean overturning, driven by heightened wind-driven upwelling, and sea-ice retreat, which are directly correlated to the warming of the Antarctic, and also coinciding with the cold events, the Oldest and Younger Dryas, in the north. Throughout the LGM in North America,

2072-427: The ice bergs were split and shed (calved) off. Large lakes became prevalent, but so did smaller, shallower, relatively short-lived lakes. This appearance and disappearance of small, shallow lakes influenced much of the plant growth, spread and diversity that we see today. The lakes acted as barriers to plant migration, but when these lakes drained, the plants could migrate and spread very efficiently. The period between

2128-409: The ice jam breakup happened in late February after record warm weather in the region. These ice jams can cause considerable damage to structures along the riverbanks and on the floodplain. The most severe flood of record on the main trunk of the Mohawk River was the spring breakup flood that occurred from 27 to 28 March 1914. This flood caused a tremendous amount of damage to the infrastructure because it

2184-473: The land. First and foremost, as huge glaciers melt, there is a consequently large volume of meltwater. The volumes of meltwater created many features, including proglacial freshwater lakes, which can be sizable. Not only was there meltwater that formed lakes, there were also storms that blew over the inland freshwater. These storms created waves strong enough to erode the ice shores. Once ice cliffs were exposed, due to rising sea levels and erosion caused by waves,

2240-530: The mountains to the north or south of the valley. As a result, it was strategically important during the French and Indian War and the American Revolutionary War , and a number of important battles were fought here. The fertile Mohawk Valley also attracted early settlers. The river was the highway of the native Mohawk people . The Mohawk name for the river is Teionontatátie , "a river flowing through

2296-480: The ocean. The recent period of intense deglaciation has resulted in an average global sea level rise of 1.7 mm/year for the entire 20th century, and 3.2 mm/year over the past two decades, a very rapid increase. The physical mechanisms by which deglaciation occurs include melting , evaporation , sublimation , calving , and aeolian processes such as wind scouring. Throughout the Pleistocene Epoch,

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2352-473: The period of Deglaciation. During the Last Glacial Maximum (LGM), there were apparent low atmospheric concentration of Carbon Dioxide (CO 2 ), which was believed to be as a result of larger containment of carbon in the deep ocean, via the process of stratification within the Southern Ocean. These Southern Ocean deep waters contained the least δ13C, which consequently resulted in them being the location with

2408-490: The project were issued on November 15, 1962. Construction work began on February 25, 1963, with construction being completed on June 4, 1965. The flood walls protect the city of Amsterdam from floods of 122,500 cu ft/s (3,470 m/s) from the Mohawk River and floods of 3,400 cu ft/s (96 m/s) from South Chuctanunda Creek. The floodwalls were able to prevent $ 13.6 million in damages from tropical storms Lee and Irene . In July 2012, governor Cuomo announced

2464-525: The reach of their efforts from the Hudson River to the Mohawk as well. West Branch Mohawk River (New York) West Branch Mohawk River is a river in Oneida County, New York . It begins at the confluence of Egger Brook and Lyman Brook , flows through the hamlet of West Branch , and empties into Mohawk River east of the hamlet. This article about a location in Oneida County, New York

2520-445: The rising sea levels did not happen until after 11ka. Nonetheless, the globe had arrived at its present interglacial period, where climate is comparatively constant and stable, and greenhouse gas concentrations exhibit near pre-industrial levels. This data is all available due to studies and information gathered from proxy records, both from the terrestrial and ocean, which illustrates overall global patterns of changes in climate whilst in

2576-540: The river in the mid-18th century where he encountered some of the indigenous peoples belonging to the Iroquois confederacy, and has left a record for posterity of some of their customs in his journal. In the early nineteenth century water transport was a vital means of transporting both people and goods. A corporation was formed to build the Erie Canal off the Mohawk River to Lake Erie . Its construction simplified and reduced

2632-751: The south. Overall, this part of New York is represented by lower Paleozoic sedimentary rocks that unconformably overlie the Grenville -aged ( Proterozoic , here about 1.1 billion years old) metamorphic rocks of the Adirondacks. In the watershed, these rocks are only significant in the headwaters of the West Canada Creek. Much of the main trunk of the Mohawk River sits in Cambro - Ordovician carbonates ( limestone ) and Middle Ordovician sandstones and shales . The southern tributaries (Catskill Mountains) are underlain by

2688-659: The speed and scope of deglaciation globally. Research published in 2014 suggests that below Greenland 's Russell Glacier 's ice sheet, methanotrophs could serve as a biological methane sink for the subglacial ecosystem, and the region was at least during the sample time, a source of atmospheric methane . Based on dissolved methane in water samples, Greenland may represent a significant global methane source, and may contribute significantly more due to ongoing deglaciation. A study in 2016 concluded based on past evidence, that below Greenland's and Antarctica's ice sheet may exist methane clathrates . At every scale, climate influences

2744-448: The tributaries and the main trunk of the river. The maximum average daily flow on the river occurs between late March and early April. For the period between 1917 and 2000, the highest mean daily flow is c. 18,000 cu ft (510 m) as measured at Cohoes, near the confluence with the Hudson. The lowest mean daily flow of 1,400 cu ft (40 m) occurs in late August. There is

2800-435: The understanding of the glacial dynamics and geologic periods of the past. Studying exposed landforms can also inform the understanding of the present and near future as glaciers all over the world retreat in the current period of climate change. In general, recently deglacialized landscapes are inherently unstable and will tend to move towards an equilibrium. A sampling of common landforms caused by deglaciation, or caused by

2856-527: The way. After North Western it receives Tannery Brook then Wells Creek in the Hamlet of Frenchville . At Frenchville it curves to the southwest and heads toward the Hamlet of Westernville receiving Deans Gulf along the way. In Westernville it enters Delta Reservoir . After exiting the reservoir it heads south toward the City of Rome receiving Hurlbut Glen Brook and passing the Rome Fish Hatchery along

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2912-436: The way. On the south side of the City it enters the Erie Canal and begins to flow east. After Rome the river flows generally east through the Mohawk Valley , passing by the cities of Utica , Little Falls , Canajoharie , Amsterdam , and Schenectady before entering the Hudson River at Cohoes , just north of Albany. The river and its supporting canal, the Erie Canal , connect the Hudson River and port of New York with

2968-472: Was a spring breakup flood with enormous amounts of ice. Ice jams of some significance occur about every other year. One major flood on the Mohawk was on 26–29 June 2006, during the Mid-Atlantic United States flood of 2006 . Flooding was caused by a stalled frontal system that resulted in 50 to 330 millimeters (2.0 to 13.0 in) of rain across central New York and widespread flooding occurred in

3024-467: Was an annual mean atmospheric temperature on the earth that increased by roughly 5 °C, which was also accompanied by regional high-latitude warming that exceeded 10 °C. This was also followed by noteworthy deep-sea and tropical-sea warming, of about 1–2 °C (deep-sea) and 2–4 °C (tropical sea). Not only did this warming occur, but the global hydrological budget also experienced noticeable changes and regional precipitation patterns changed. As

3080-512: Was completed in 1926 as part of the New York City water supply system , is the subject of an active and aggressive rehabilitation project. The Mohawk watershed drains a large section of the Catskill Mountains , the Mohawk Valley proper, and a section of the southern Adirondack Mountains . All three regions have distinct bedrock geology, and the underlying rocks become progressively younger to

3136-516: Was the outpost of civilization and Dutch-English rule in the Mohawk valley." In 1712 the British, now in control of New York, built Fort Hunter at the confluence of the Mohawk and the Schoharie Creek , about 22 miles (35 km) upriver from Schenectady. Around 600 Palatine Germans were settled along the Mohawk and Schoharie Creek. Swedish explorer and botanist, Pehr Kalm , visited the area along

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