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Arctic Front
The Arctic front is the semipermanent, semi-continuous weather front between the cold arctic air mass and the warmer air of the polar cell. It can also be defined as the southern boundary of the Arctic air mass. Mesoscale cyclones known as polar lows can form along the arctic front in the wake of extratropical cyclones. Arctic air masses in their wake are shallow with a deep layer of stable air above the shallow cold cool. Appearance in satellite images Arctic Fronts form in the Arctic region, and move southwards in southerly flows. When they reach Northern Europe, they have usually travelled over an open sea, and convective cloudiness has developed. The appearance of an Arctic Cold Fronts is then, essentially, that of a shallow Cold Front. Arctic Cold Fronts are usually so far north that Meteosat The Meteosat series of satellites are geostationary meteorological satellites operated by EUMETSAT under the Meteosat Transition Programme (MTP) and the Meteosat Second Generat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weather Front
A weather front is a boundary separating air masses for which several characteristics differ, such as air density, wind, temperature, and humidity. Disturbed and unstable weather due to these differences often arises along the boundary. For instance, cold fronts can bring bands of thunderstorms and cumulonimbus precipitation or be preceded by squall lines, while warm fronts are usually preceded by stratiform precipitation and fog. In summer, subtler humidity gradients are known as dry lines can trigger severe weather. Some fronts produce no precipitation and little cloudiness, although there is invariably always a wind shift. Cold fronts generally move from west to east, whereas warm fronts move poleward, although any direction is possible. Occluded fronts are a hybrid merge of the two, and stationary fronts are stalled in their motion. Cold fronts and cold occlusions move faster than warm fronts and warm occlusions because the dense air behind them can lift as well as push ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Mass
In meteorology, an air mass is a volume of air defined by its temperature and humidity. Air masses cover many hundreds or thousands of square miles, and adapt to the characteristics of the surface below them. They are classified according to latitude and their continental or maritime source regions. Colder air masses are termed polar or arctic, while warmer air masses are deemed tropical. Continental and superior air masses are dry, while maritime and monsoon air masses are moist. Weather fronts separate air masses with different density (temperature or moisture) characteristics. Once an air mass moves away from its source region, underlying vegetation and body of water, water bodies can quickly modify its character. Classification schemes tackle an air mass' characteristics, as well as modification. Classification and notation The Tor Bergeron, Bergeron classification is the most widely accepted form of air mass classification, though others have produced more refined versions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Cells
Atmospheric circulation is the large-scale movement of air and together with ocean circulation is the means by which thermal energy is redistributed on the surface of the Earth. The Earth's atmospheric circulation varies from year to year, but the large-scale structure of its circulation remains fairly constant. The smaller scale weather systems – mid-latitude depressions, or tropical convective cells – occur chaotically, and long-range weather predictions of those cannot be made beyond ten days in practice, or a month in theory (see chaos theory and the butterfly effect). The Earth's weather is a consequence of its illumination by the Sun and the laws of thermodynamics. The atmospheric circulation can be viewed as a heat engine driven by the Sun's energy and whose energy sink, ultimately, is the blackness of space. The work produced by that engine causes the motion of the masses of air, and in that process it redistributes the energy absorbed by the Earth's surface near t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Low
A polar low is a mesoscale, short-lived atmospheric low pressure area, low pressure system (depression) that is found over the ocean areas poleward of the main polar front in both the Northern and Southern Hemispheres, as well as the Sea of Japan. The systems usually have a horizontal length scale of less than and exist for no more than a couple of days. They are part of the larger class of mesoscale meteorology, mesoscale weather systems. Polar lows can be difficult to detect using conventional weather reports and are a hazard to high-latitude operations, such as shipping and gas and oil platforms. Polar lows have been referred to by many other terms, such as polar mesoscale vortex, Arctic hurricane, Arctic low, and cold air depression. Today the term is usually reserved for the more vigorous systems that have near-surface winds of at least 17 m/s (38 mph). History Polar lows were first identified on the meteorological satellite imagery that became available in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extratropical Cyclone
Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are low-pressure areas which, along with the anticyclones of high-pressure areas, drive the weather over much of the Earth. Extratropical cyclones are capable of producing anything from cloudiness and mild showers to severe gales, thunderstorms, blizzards, and tornadoes. These types of cyclones are defined as large scale (synoptic) low pressure weather systems that occur in the middle latitudes of the Earth. In contrast with tropical cyclones, extratropical cyclones produce rapid changes in temperature and dew point along broad lines, called weather fronts, about the center of the cyclone. Terminology The term " cyclone" applies to numerous types of low pressure areas, one of which is the extratropical cyclone. The descriptor ''extratropical'' signifies that this type of cyclone generally occurs outside the tropics and in the middle latitudes of Earth between 30° and 60° latitude. They are term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteosat
The Meteosat series of satellites are geostationary meteorological satellites operated by EUMETSAT under the Meteosat Transition Programme (MTP) and the Meteosat Second Generation (MSG) program. The MTP program was established to ensure the operational continuity between the end of the successful Meteosat Operational Programme in 1995 and Meteosat Second Generation (MSG), which came into operation at the start of 2004 using improved satellites. The MSG program will provide service until the MTG (Meteosat Third Generation) program takes over. __TOC__ First generation The first generation of Meteosat satellites, Meteosat-1 to Meteosat-7, provided continuous and reliable meteorological observations from space to a large user community. Meteosat-1 to -7 have all now retired. When operational, the Meteosat First Generation provided images every half-hour in three spectral channels (Visible, Infrared) and Water Vapour, via the Meteosat Visible and Infrared Imager (MVIRI) instrum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Climate
The polar climate regions are characterized by a lack of warm summers but with varying winters. Every month in a polar climate has an average temperature of less than . Regions with polar climate cover more than 20% of the Earth's area. Most of these regions are far from the equator and near the poles, and in this case, winter days are extremely short and summer days are extremely long (could last for the entirety of each season or longer). A polar climate consists of cool summers and very cold winters, which results in treeless tundra, glaciers, or a permanent or semi-permanent layer of ice. It is identified with the letter E in the Köppen climate classification. Subtypes There are two types of polar climate: ET, or tundra climate; and EF, or ice cap climate. A tundra climate is characterized by having at least one month whose average temperature is above , while an ice cap climate has no months averaging above . In a tundra climate, even coniferous trees cannot grow, but o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Dynamics
Meteorology is a branch of the atmospheric sciences (which include atmospheric chemistry and physics) with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did not begin until the 18th century. The 19th century saw modest progress in the field after weather observation networks were formed across broad regions. Prior attempts at prediction of weather depended on historical data. It was not until after the elucidation of the laws of physics, and more particularly in the latter half of the 20th century the development of the computer (allowing for the automated solution of a great many modelling equations) that significant breakthroughs in weather forecasting were achieved. An important branch of weather forecasting is marine weather forecasting as it relates to maritime and coastal safety, in which weather effects also include atmospheric interactions with large bodies of water. Meteorological phenom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Environment Of The Arctic
Environment most often refers to: __NOTOC__ * Natural environment, all living and non-living things occurring naturally * Biophysical environment, the physical and biological factors along with their chemical interactions that affect an organism or a group of organisms Other physical and cultural environments *Ecology, the branch of ethology that deals with the relations of organisms to one another and to their physical surroundings *Environment (systems), the surroundings of a physical system that may interact with the system by exchanging mass, energy, or other properties *Built environment, constructed surroundings that provide the setting for human activity, ranging from the large-scale civic surroundings to the personal places *Social environment, the culture that an individual lives in, and the people and institutions with whom they interact *Market environment, business term Arts, entertainment and publishing * ''Environment'' (magazine), a peer-reviewed, popular enviro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
