40-614: Gilmanton is the name of several places in the United States: Gilmanton, New Hampshire , a town Gilmanton, Wisconsin , a town in Buffalo County Gilmanton (community), Wisconsin , an unincorporated community in the town of Gilmanton Gilmanton Township, Benton County, Minnesota [REDACTED] Topics referred to by the same term This disambiguation page lists articles about distinct geographical locations with
80-409: A defined barometric pressure . Generally, the pressure used to set the altimeter is the barometric pressure that would exist at MSL in the region being flown over. This pressure is referred to as either QNH or "altimeter" and is transmitted to the pilot by radio from air traffic control (ATC) or an automatic terminal information service (ATIS). Since the terrain elevation is also referenced to MSL,
120-432: A few metres, in timeframes ranging from minutes to months: Between 1901 and 2018, the average sea level rose by 15–25 cm (6–10 in), with an increase of 2.3 mm (0.091 in) per year since the 1970s. This was faster than the sea level had ever risen over at least the past 3,000 years. The rate accelerated to 4.62 mm (0.182 in)/yr for the decade 2013–2022. Climate change due to human activities
160-462: A household in the town was $ 50,542, and the median income for a family was $ 51,712. Males had a median income of $ 37,077 versus $ 27,727 for females. The per capita income for the town was $ 23,163. About 3.3% of families and 5.9% of the population were below the poverty line , including 5.8% of those under age 18 and 9.1% of those age 65 or over. In the New Hampshire Senate , Gilmanton is in
200-438: A reference datum for mean sea level (MSL). It is also used in aviation, where some heights are recorded and reported with respect to mean sea level (contrast with flight level ), and in the atmospheric sciences , and in land surveying . An alternative is to base height measurements on a reference ellipsoid approximating the entire Earth, which is what systems such as GPS do. In aviation, the reference ellipsoid known as WGS84
240-463: A sharp reduction in greenhouse gas emissions, this may increase to hundreds of millions in the latter decades of the century. Local factors like tidal range or land subsidence will greatly affect the severity of impacts. For instance, sea level rise in the United States is likely to be two to three times greater than the global average by the end of the century. Yet, of the 20 countries with
280-514: Is Mount Mack, at 1,945 feet (593 m) above sea level , on the town line with Gilford. Crystal Lake is in the east, and Shellcamp Pond is in the west. Gilmanton lies fully within the Merrimack River watershed . The town is served by four state routes: 106 , 129 , 107 and 140 . Route 107 is part of Old Province Road, an important road in New Hampshire's early history, and Route 106
320-478: Is a town in Belknap County, New Hampshire , United States. The population was 3,945 at the 2020 census . Gilmanton includes the villages of Gilmanton Corners and Gilmanton Ironworks . The town became well known in the 1950s after it was rumored that the popular novel Peyton Place , written by resident Grace Metalious , was based on the town. Gilmanton was incorporated in 1727. First known as "Gilmantown",
360-422: Is a well-traveled connection between Laconia and Concord . Route 140 is an east-west highway leading from Tilton to Alton . The intersection NH 107 and NH 140 is at Gilmanton Corners, one of the two major villages. Gilmanton Corner (or simply "Gilmanton", as shown on topographic maps) is the location of several historic buildings, including Gilmanton Academy and Centre Congregational Church. Gilmanton Ironworks
400-417: Is an average surface level of one or more among Earth 's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datum – a standardised geodetic datum – that is used, for example, as a chart datum in cartography and marine navigation , or, in aviation, as the standard sea level at which atmospheric pressure
440-488: Is because the sea is in constant motion, affected by the tides, wind , atmospheric pressure, local gravitational differences, temperature, salinity , and so forth. The mean sea level at a particular location may be calculated over an extended time period and used as a datum . For example, hourly measurements may be averaged over a full Metonic 19-year lunar cycle to determine the mean sea level at an official tide gauge . Still-water level or still-water sea level (SWL)
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#1732858737202480-427: Is due to change in either the volume of water in the world's oceans or the volume of the oceanic basins . Two major mechanisms are currently causing eustatic sea level rise. First, shrinking land ice, such as mountain glaciers and polar ice sheets, is releasing water into the oceans. Second, as ocean temperatures rise, the warmer water expands. Many factors can produce short-term changes in sea level, typically within
520-483: Is increasingly used to define heights; however, differences up to 100 metres (328 feet) exist between this ellipsoid height and local mean sea level. Another alternative is to use a geoid -based vertical datum such as NAVD88 and the global EGM96 (part of WGS84). Details vary in different countries. When referring to geographic features such as mountains, on a topographic map variations in elevation are shown by contour lines . A mountain's highest point or summit
560-501: Is located in the eastern part of town along NH 140, near the outlet of Crystal Lake. Gilmanton's population was ranked #38, #31, and #37 in the country respectively in the 1790, 1800, and 1810 censuses. As of the 2000 census , there were 3,060 people, 1,165 households, and 900 families residing in the town. The population density was 53.6 inhabitants per square mile (20.7/km ). There were 1,848 housing units at an average density of 32.4 per square mile (12.5/km ). The racial makeup of
600-512: Is measured to calibrate altitude and, consequently, aircraft flight levels . A common and relatively straightforward mean sea-level standard is instead a long-term average of tide gauge readings at a particular reference location. Sea levels can be affected by many factors and are known to have varied greatly over geological time scales . Current sea level rise is mainly caused by human-induced climate change . When temperatures rise, mountain glaciers and polar ice sheets melt, increasing
640-447: Is the level of the sea with motions such as wind waves averaged out. Then MSL implies the SWL further averaged over a period of time such that changes due to, e.g., the tides , also have zero mean. Global MSL refers to a spatial average over the entire ocean area, typically using large sets of tide gauges and/or satellite measurements. One often measures the values of MSL with respect to
680-723: Is the main cause. Between 1993 and 2018, melting ice sheets and glaciers accounted for 44% of sea level rise , with another 42% resulting from thermal expansion of water . Sea level rise lags behind changes in the Earth 's temperature by many decades, and sea level rise will therefore continue to accelerate between now and 2050 in response to warming that has already happened. What happens after that depends on human greenhouse gas emissions . If there are very deep cuts in emissions, sea level rise would slow between 2050 and 2100. It could then reach by 2100 slightly over 30 cm (1 ft) from now and approximately 60 cm (2 ft) from
720-527: Is typically illustrated with the AMSL height in metres, feet or both. In unusual cases where a land location is below sea level, such as Death Valley, California , the elevation AMSL is negative. It is often necessary to compare the local height of the mean sea surface with a "level" reference surface, or geodetic datum, called the geoid . In the absence of external forces, the local mean sea level would coincide with this geoid surface, being an equipotential surface of
760-612: The geoid of the Earth, which approximates the local mean sea level for locations in the open ocean. The geoid includes a significant depression in the Indian Ocean , whose surface dips as much as 106 m (348 ft) below the global mean sea level (excluding minor effects such as tides and currents). Precise determination of a "mean sea level" is difficult because of the many factors that affect sea level. Instantaneous sea level varies substantially on several scales of time and space. This
800-418: The height above mean sea level (AMSL). The term APSL means above present sea level, comparing sea levels in the past with the level today. Earth's radius at sea level is 6,378.137 km (3,963.191 mi) at the equator. It is 6,356.752 km (3,949.903 mi) at the poles and 6,371.001 km (3,958.756 mi) on average. This flattened spheroid , combined with local gravity anomalies , defines
840-544: The 1690s. Satellite altimeters have been making precise measurements of sea level since the launch of TOPEX/Poseidon in 1992. A joint mission of NASA and CNES , TOPEX/Poseidon was followed by Jason-1 in 2001 and the Ocean Surface Topography Mission on the Jason-2 satellite in 2008. Height above mean sea level ( AMSL ) is the elevation (on the ground) or altitude (in the air) of an object, relative to
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#1732858737202880-973: The 19th century. With high emissions it would instead accelerate further, and could rise by 1.0 m ( 3 + 1 ⁄ 3 ft) or even 1.6 m ( 5 + 1 ⁄ 3 ft) by 2100. In the long run, sea level rise would amount to 2–3 m (7–10 ft) over the next 2000 years if warming stays to its current 1.5 °C (2.7 °F) over the pre-industrial past. It would be 19–22 metres (62–72 ft) if warming peaks at 5 °C (9.0 °F). Rising seas affect every coastal and island population on Earth. This can be through flooding, higher storm surges , king tides , and tsunamis . There are many knock-on effects. They lead to loss of coastal ecosystems like mangroves . Crop yields may reduce because of increasing salt levels in irrigation water. Damage to ports disrupts sea trade. The sea level rise projected by 2050 will expose places currently inhabited by tens of millions of people to annual flooding. Without
920-597: The 6th district, represented by Republican James Gray. On the New Hampshire Executive Council , Gilmanton is in the 2nd district, represented by Democrat Andru Volinsky . In the United States House of Representatives , Gilmanton is in New Hampshire's 1st congressional district , represented by Democrat Chris Pappas . Sea level Mean sea level ( MSL , often shortened to sea level )
960-448: The Earth's gravitational field which, in itself, does not conform to a simple sphere or ellipsoid and exhibits gravity anomalies such as those measured by NASA's GRACE satellites . In reality, the geoid surface is not directly observed, even as a long-term average, due to ocean currents, air pressure variations, temperature and salinity variations, etc. The location-dependent but time-persistent separation between local mean sea level and
1000-672: The Marégraphe in Marseilles measures continuously the sea level since 1883 and offers the longest collated data about the sea level. It is used for a part of continental Europe and the main part of Africa as the official sea level. Spain uses the reference to measure heights below or above sea level at Alicante , while the European Vertical Reference System is calibrated to the Amsterdam Peil elevation, which dates back to
1040-456: The amount of water in the oceans, while the existing seawater also expands with heat. Because most of human settlement and infrastructure was built in response to a more-normalized sea level with limited expected change, populations affected by sea level rise will need to invest in climate adaptation to mitigate the worst effects or, when populations are at extreme risk, a process of managed retreat . The term above sea level generally refers to
1080-482: The geoid is referred to as (mean) ocean surface topography . It varies globally in a typical range of ±1 m (3 ft). Several terms are used to describe the changing relationships between sea level and dry land. The melting of glaciers at the end of ice ages results in isostatic post-glacial rebound , when land rises after the weight of ice is removed. Conversely, older volcanic islands experience relative sea level rise, due to isostatic subsidence from
1120-624: The greatest exposure to sea level rise, twelve are in Asia , including Indonesia , Bangladesh and the Philippines. The resilience and adaptive capacity of ecosystems and countries also varies, which will result in more or less pronounced impacts. The greatest impact on human populations in the near term will occur in the low-lying Caribbean and Pacific islands . Sea level rise will make many of them uninhabitable later this century. Pilots can estimate height above sea level with an altimeter set to
1160-551: The height of planetary features. Local mean sea level (LMSL) is defined as the height of the sea with respect to a land benchmark, averaged over a period of time long enough that fluctuations caused by waves and tides are smoothed out, typically a year or more. One must adjust perceived changes in LMSL to account for vertical movements of the land, which can occur at rates similar to sea level changes (millimetres per year). Some land movements occur because of isostatic adjustment to
1200-576: The land; hence a change in relative MSL or ( relative sea level ) can result from a real change in sea level, or from a change in the height of the land on which the tide gauge operates, or both. In the UK, the ordnance datum (the 0 metres height on UK maps) is the mean sea level measured at Newlyn in Cornwall between 1915 and 1921. Before 1921, the vertical datum was MSL at the Victoria Dock, Liverpool . Since
1240-481: The melting of ice sheets at the end of the last ice age . The weight of the ice sheet depresses the underlying land, and when the ice melts away the land slowly rebounds . Changes in ground-based ice volume also affect local and regional sea levels by the readjustment of the geoid and true polar wander . Atmospheric pressure , ocean currents and local ocean temperature changes can affect LMSL as well. Eustatic sea level change (global as opposed to local change)
Gilmanton - Misplaced Pages Continue
1280-413: The original building burned; the second building also burned, in 1894, and was replaced with the current building, which now houses the town offices. Gilmanton Theological Seminary was provided for by the terms of the original charter of Gilmanton Academy. Rev. Heman Rood, from New Milford, Connecticut , was the first professor in 1835. By 1841 a large, three-story brick building designed by Ammi B. Young
1320-475: The same name. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Gilmanton&oldid=1224269279 " Category : Place name disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Gilmanton, New Hampshire Gilmanton
1360-507: The times of the Russian Empire , in Russia and its other former parts, now independent states, the sea level is measured from the zero level of Kronstadt Sea-Gauge. In Hong Kong, "mPD" is a surveying term meaning "metres above Principal Datum" and refers to height of 0.146 m (5.7 in) above chart datum and 1.304 m (4 ft 3.3 in) below the average sea level. In France,
1400-501: The town was 98.59% White, 0.10% African American, 0.20% Native American, 0.13% Asian, and 0.98% from two or more races. Hispanic or Latino of any race were 0.29% of the population. There were 1,165 households, out of which 33.1% had children under the age of 18 living with them, 68.8% were married couples living together, 5.5% had a female householder with no husband present, and 22.7% were non-families. 17.2% of all households were made up of individuals, and 5.8% had someone living alone who
1440-708: The town was home to the Gilman family, originally settled at Exeter . Twenty-four members of the Gilman family received land grants in the new town of Gilmanton. (Other families related to the Gilmans also received grants in the new town, including the Dudleys, the Leavitts, the Folsoms and the Coffins.) At one time it was the second-largest town in the state, following Portsmouth . The original town
1480-411: The weight of cooling volcanos. The subsidence of land due to the withdrawal of groundwater is another isostatic cause of relative sea level rise. On planets that lack a liquid ocean, planetologists can calculate a "mean altitude" by averaging the heights of all points on the surface. This altitude, sometimes referred to as a "sea level" or zero-level elevation , serves equivalently as a reference for
1520-451: Was 65 years of age or older. The average household size was 2.62 and the average family size was 2.96. In the town, the population was spread out, with 24.2% under the age of 18, 5.9% from 18 to 24, 30.5% from 25 to 44, 27.6% from 45 to 64, and 11.7% who were 65 years of age or older. The median age was 40 years. For every 100 females, there were 102.9 males. For every 100 females age 18 and over, there were 100.1 males. The median income for
1560-600: Was completed for the seminary's use. According to the United States Census Bureau , the town has a total area of 59.6 square miles (154.4 km ), of which 57.9 square miles (150.0 km ) are land and 1.7 square miles (4.4 km ) are water, comprising 2.89% of the town. A natural resources inventory published in 2004 noted the town's nine town forests and other dry and wetland protected areas as well as significant plant species. The highest point in Gilmanton
1600-407: Was larger than it is now, with villages and parishes including Belmont , Gunstock Parish ( Gilford ), Hurricane, Tioga, Factory Village and Lakeport. A parish first called "Averytown", the site of an unprofitable iron - mining enterprise, is still known as Gilmanton Iron Works. Gilmanton Academy was incorporated in 1794 as "...one of the three academies first founded in the state...". In 1808
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