| 释义 |
sea level
sea leveln. Abbr. SL1. The level of the ocean's surface, especially the level halfway between mean high and low tide.2. Mean sea level.sea level n (Physical Geography) the level of the surface of the sea with respect to the land, taken to be the mean level between high and low tide, and used as a standard base for measuring heights and depths sea′ lev`el
n. the horizontal plane corresponding to the surface of the sea at mean level between high and low tide. [1800–10] sea level The level of the surface of the ocean, used as a standard in determining land elevation or sea depths.Thesaurus| Noun | 1. |  sea level - level of the ocean's surface (especially that halfway between mean high and low tide); used as a standard in reckoning land elevation or sea depthwater level - the level of the surface of a body of water |
Translationssea (siː) noun1. (often with the) the mass of salt water covering most of the Earth's surface. I enjoy swimming in the sea; over land and sea; The sea is very deep here; (also adjective) A whale is a type of large sea animal. 海洋 海洋2. a particular area of sea. the Baltic Sea; These fish are found in tropical seas. (專用名詞中的)海，內海 （专用名词中的）海，内海 3. a particular state of the sea. mountainous seas. 特定狀態中的海 海（域） ˈseaward(s) adverb towards the sea; away from the land. The yacht left the harbour and sailed seawards. 航向大海，駛離陸地 向海（航行） ˈseaboard noun the seacoast. the eastern seaboard of the United States. 海岸 海岸，沿海地区 sea breeze a breeze blowing from the sea towards the land. 海風 海风ˈseafaring adjective of work or travel on ships. a seafaring man. 航海作業或旅遊的 以航海为业的ˈseafood noun fish, especially shellfish. 海鮮(尤指貝類) 海味，海鲜 adjectiveseafood restaurants. 海鮮的 海味的，海鲜的 ˈseafront noun a promenade or part of a town with its buildings facing the sea. 濱海步道，濱海區 海岸区，海滨区 ˈsea-going adjective designed and equipped for travelling on the sea. a sea-going yacht. 用於航海的 适于航海的ˈseagull noun a gull. 海鷗 海鸥sea level the level of the surface of the sea used as a base from which the height of land can be measured. three hundred metres above sea level. 海平線 海平线ˈsea-lion noun a type of large seal. 海獅 海狮ˈseaman – plural ˈseamen – noun a sailor, especially a member of a ship's crew who is not an officer. 海員，水手 海员，水手 ˈseaport noun a port on the coast. 海港 海港ˈseashell noun the (empty) shell of a sea creature. 貝殼 海贝，贝壳 ˈseashore noun the land close to the sea. 海岸，海濱 海岸，海滨 ˈseasick adjective ill because of the motion of a ship at sea. Were you seasick on the voyage? 暈船的 晕船的ˈseasickness noun 暈船 晕船ˈseaside noun (usually with the) a place beside the sea. We like to go to the seaside in the summer. 海邊 海边ˈseaweed noun plants growing in the sea. The beach was covered with seaweed. 海草 海草ˈseaworthy adjective (negative unseaworthy) (of a ship) suitably built and in good enough condition to sail at sea. 經得起風浪的 经得起风浪的ˈseaworthiness noun (船的)適航性 （船的）适航性 at sea1. on a ship and away from land. He has been at sea for four months. 出海，在海上航行 出海，在海上航行 2. puzzled or bewildered. Can I help you? You seem all at sea. 不知所措 不知所措go to sea to become a sailor. He wants to go to sea. 成為水手 去当水手put to sea to leave the land or a port. They planned to put to sea the next day. 出航 出航，启航 sea level
sea level, the level of the sea, which serves as the datum used for measurement of land elevations and ocean depths. Theoretically, one would expect sea level to be a fixed and permanent horizontal surface on the face of the earth, and as a starting approximation, this is true. However, a number of factors operate to cause variations in sea level ranging up to several meters from place to place and to cause long-term global variations, often severe enough to cause flooding and damage to coastal zones. Sea levels vary greatly from one location to another, i.e., between Nova Scotia and Florida sea-level heights differ at about 16 in (40 cm). Locally the levels of the surface of the world's oceans are disturbed by wind-driven waves and tidestide,
alternate and regular rise and fall of sea level in oceans and other large bodies of water. These changes are caused by the gravitational attraction of the moon and, to a lesser extent, of the sun on the earth.
..... Click the link for more information. . Sea level therefore fluctuates in periods ranging from seconds to a year as a result of these factors. Thus for some purposes it is necessary to know the mean sea level (MSL) in a particular area, determined by averaging the elevations of the sea's surface as measured by mechanical tide gauges over long periods of time. A number of other factors result in sea-level differences between one place or time and another. These may complement or counteract one another to result in a net rise or fall in mean sea level at a particular time and place. These factors include water temperature and salinity, air pressure, change of season, the amount of runoff from streams, and the amount of water stored as ice or snow on land. Characteristics of the earth also cause differences in sea level. Satellite measurements of the gravity field have shown that the earth is not a perfectly smooth sphere, making defining sea-level measurements difficult. Worldwide, or eustatic, sea levels have changed over time, such as the last ice age when sea level was as much as 333 ft (100 m) lower in many areas than today. These changes are due to a multitude of reasons. Past transgression (or rise) or regression (or lowering) of the seas have been caused mainly by the addition or removal of water from continental ice caps. Such sea-level fluctuations may be due to changes in climateclimate,
average condition of the atmosphere near the earth's surface over a long period of time, taking into account temperature, precipitation (see rain), humidity, wind, barometric pressure, and other phenomena.
..... Click the link for more information. that cause the ice to melt or accumulate. Theories of climate and sea level change in geologic time include differences in carbon dioxide or oxygen levels, changes due to plate tectonics and earthquake activity, volcanic and asteroid activity, or changes in the sun's energy. Since the Industrial Revolution the increase in carbon dioxide and other greenhouse gases caused by the burning of fossil fuel, deforestation of tropical rain forests, and other human activities has led to global warmingglobal warming,
the gradual increase of the temperature of the earth's lower atmosphere as a result of the increase in greenhouse gases since the Industrial Revolution. Global warming and its effects, such as more intense summer and winter storms, are also referred to as climate
..... Click the link for more information. and a resulting increase in sea level greater than that that would have been expected otherwise. Rising sea levels result in increased coastal flooding and the permanent inundation of coastal lands (in some cases threatening the existence of island nations). The economic implications of rising sea levels are magnified by the percentage of the world's population (more than one fifth) that lives near the coast, and the concentration of urban and industrial areas close to the coast. Sea Level the position that the surface of seas and oceans would assume if uninfluenced by tides, waves, or swells, measured as the vertical distance between the water surface and a reference point on land. Sea level is classified as instantaneous, tidal, daily mean, monthly mean, annual mean, and long-term mean. Sea level is constantly changing under the influence of wind disturbances, tides, the heating and cooling of the ocean surface, atmospheric pressure fluctuations, precipitation and evaporation, and river and glacial runoff. Long-term mean sea level, however, is not affected by these factors; it is determined by the distribution of gravity and by the uneven spatial distribution of such hydrometeorological characteristics as water density and atmospheric pressure. Long-term mean sea level, which is constant at any given point, is used as a reference level from which land elevations are measured. In order to determine the depths of seas with minimal tidal variation, long-term mean sea level is taken as zero depth, from which depths are calculated in accordance with navigational requirements. In the USSR, absolute elevations on the earth’s surface are measured from the long-term mean sea level of the Baltic Sea, which is read off from the zero point of the tide gage at Kronstadt. REFERENCESDuvanin, A. I. Uroven’ moria. Leningrad, 1956.
Duvanin, A. I., G. P. Kalinin, and R. K. Klige. “O mnogoletnikh kolebaniiakh urovnia okeanov, nekotorykh morei i ozer.” Vestnik MGU, Seriia 5: Geografiia, 1975, no. 6.sea level[′sē ‚lev·əl] (geology) The level of the surface of the ocean; especially, the mean level halfway between high and low tide, used as a standard in reckoning land elevation or sea depths. sea levelThe level of the sea, which serves as the datum used for measurement of land elevations and ocean depths. Sea levels vary greatly from one location to another. Locally, the levels of the surface of the world's oceans are disturbed by wind-driven waves and tides. The mean sea level is used as a reference height to determine a standard condition for the atmosphere and for the altitude measurement. It is measured over a nineteen-year period. It does not remain constant over the surface of the entire earth; the mean sea level at the Pacific end of the Panama Canal stands 7.8 in (20 cm) higher than at the Atlantic end.sea level the level of the surface of the sea with respect to the land, taken to be the mean level between high and low tide, and used as a standard base for measuring heights and depths MedicalSeeseaLegalSeeSEAAcronymsSeeslalomsea level
Words related to sea levelnoun level of the ocean's surface (especially that halfway between mean high and low tide)Related Words |