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Rainstorm
Rain is a form of precipitation where water droplets that have condensed from atmospheric water vapor fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. It provides water for hydroelectric power plants, crop irrigation, and suitable conditions for many types of ecosystems. The major cause of rain production is moisture moving along three-dimensional zones of temperature and moisture contrasts known as weather fronts. If enough moisture and upward motion is present, precipitation falls from convective clouds (those with strong upward vertical motion) such as cumulonimbus (thunder clouds) which can organize into narrow rainbands. In mountainous areas, heavy precipitation is possible where upslope flow is maximized within windward sides of the terrain at elevation which forces moist air to condense and fall out as rainfall along the sides of mountains. On the leeward side of mountains, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weather Radar
A weather radar, also called weather surveillance radar (WSR) and Doppler weather radar, is a type of radar used to locate precipitation (meteorology), precipitation, calculate its motion, and estimate its type (rain, snow, hail etc.). Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the intensity of the precipitation. Both types of data can be analyzed to determine the structure of storms and their potential to cause severe weather. During Radar in World War II, World War II, radar operators discovered that weather was causing echoes on their screens, masking potential enemy targets. Techniques were developed to filter them, but scientists began to study the phenomenon. Soon after the war, military surplus, surplus radars were used to detect precipitation. Since then, weather radar has evolved and is used by national weather services, research departments in universities, and in television stations' weather d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precipitation
In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls from clouds due to gravitational pull. The main forms of precipitation include drizzle, rain, rain and snow mixed ("sleet" in Commonwealth usage), snow, ice pellets, graupel and hail. Precipitation occurs when a portion of the atmosphere becomes saturated with water vapor (reaching 100% relative humidity), so that the water condenses and "precipitates" or falls. Thus, fog and mist are not precipitation; their water vapor does not condense sufficiently to precipitate, so fog and mist do not fall. (Such a non-precipitating combination is a colloid.) Two processes, possibly acting together, can lead to air becoming saturated with water vapor: cooling the air or adding water vapor to the air. Precipitation forms as smaller droplets coalesce via collision with other rain drops or ice crystals within a cloud. Short, intense periods of rain in scattered locations are calle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Windward
In geography and seamanship, windward () and leeward () are directions relative to the wind. Windward is ''upwind'' from the point of reference, i.e., towards the direction from which the wind is coming; leeward is ''downwind'' from the point of reference, i.e., along the direction towards which the wind is going. The side of a ship that is towards the leeward is its "lee side". If the vessel is heeling under the pressure of crosswind, the lee side will be the "lower side". During the Age of Sail, the term ''weather'' was used as a synonym for ''windward'' in some contexts, as in the '' weather gage''. Since it captures rainfall, the windward side of a mountain tends to be wetter than the leeward side it blocks. The drier leeward area is said to be in a rain shadow. Origin The term "windward" has roots in both Low German and Old English. The word "lee", which means a place without wind, comes from the Old Norse "hle" for "cover" and has been used in marine navigation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rain Gauge
A rain gauge (also known as udometer, ombrometer, pluviometer and hyetometer) is an instrument used by meteorologists and Hydrology, hydrologists to gather and measure the amount of liquid precipitation in a predefined area, over a set period of time. It is used to determine the depth of precipitation (usually in mm) that occurs over a unit area and measure rainfall amount. History People living in India and the Ancient Greece, Ancient Greeks began to record rainfall around 400 to 500 BCE.Ian Strangeways, A History of rain gauges, TerraData, 2010 In India the readings were correlated against expected growth. In the Arthashastra, used for example in Magadha (Mahajanapada), Magadha, precise standards were set as to grain production. Each state storehouse was equipped with a rain gauge to classify land for taxation purposes. Rainfall measurement was also mentioned in the Jewish text in Palestine. In 1247, the Song (Chinese surname), Song Chinese mathematician and inventor Qin Jiushao ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Köppen Climate Classification
The Köppen climate classification divides Earth climates into five main climate groups, with each group being divided based on patterns of seasonal precipitation and temperature. The five main groups are ''A'' (tropical), ''B'' (arid), ''C'' (temperate), ''D'' (continental), and ''E'' (polar). Each group and subgroup is represented by a letter. All climates are assigned a main group (the first letter). All climates except for those in the ''E'' group are assigned a seasonal precipitation subgroup (the second letter). For example, ''Af'' indicates a tropical rainforest climate. The system assigns a temperature subgroup for all groups other than those in the ''A'' group, indicated by the third letter for climates in ''B'', ''C'', ''D'', and the second letter for climates in ''E''. Other examples include: ''Cfb'' indicating an oceanic climate with warm summers as indicated by the ending ''b.'', while ''Dwb'' indicates a semi-Monsoon continental climate, monsoonal continental climate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climate Classification
Climate zones are systems that categorize the world's climates. A climate classification may correlate closely with a biome classification, as climate is a major influence on life in a region. The most used is the Köppen climate classification scheme first developed in 1884. There are several ways to classify climates into similar regimes. Originally, climes were defined in Ancient Greece to describe the weather depending upon a location's latitude. Modern climate classification methods can be broadly divided into ''genetic'' methods, which focus on the causes of climate, and ''empiric'' methods, which focus on the effects of climate. Examples of genetic classification include methods based on the relative frequency of different air mass types or locations within synoptic scale meteorology, synoptic weather disturbances. Examples of empirical, empiric classifications include climate zones defined by plant hardiness, evapotranspiration, or associations with certain biomes, as in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Warming
Present-day climate change includes both global warming—the ongoing increase in global average temperature—and its wider effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global temperatures is driven by human activities, especially fossil fuel burning since the Industrial Revolution. Fossil fuel use, deforestation, and some agricultural and industrial practices release greenhouse gases. These gases absorb some of the heat that the Earth radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary gas driving global warming, has increased in concentration by about 50% since the pre-industrial era to levels not seen for millions of years. Climate change has an increasingly large impact on the environment. Deserts are expanding, while heat waves and wildfires are becoming more common. Amplified warming in the Arctic has c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urban Heat Island
Urban areas usually experience the urban heat island (UHI) effect; that is, they are significantly warmer than surrounding rural areas. The temperature difference is usually larger at night than during the day, and is most apparent when winds are weak, under Block (meteorology), block conditions, noticeably during the summer and winter. The main cause of the UHI effect is from the modification of land surfaces, while waste heat generated by energy usage is a secondary contributor. Urban areas occupy about 0.5% of the Earth's land surface but host more than half of the world's population. As a population center grows, it tends to expand its area and increase its average temperature. The term heat island is also used; the term can be used to refer to any area that is relatively hotter than the surrounding, but generally refers to human-disturbed areas. Monthly precipitation (meteorology), rainfall is greater downwind of cities, partially due to the UHI. Increases in heat within urb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clime
The climes (singular ''clime''; also ''clima'', plural ''climata'', from Greek κλίμα ''klima'', plural κλίματα ''klimata'', meaning "inclination" or "slope") in classical Greco-Roman geography and astronomy were the divisions of the inhabited portion of the spherical Earth by geographic latitude. Starting with Aristotle (''Meteorology'' 2.5,362a32), the Earth was divided into five zones, assuming two ''frigid'' climes (the Arctic and Antarctic) around the poles, an uninhabitable ''torrid'' clime near the equator, and two ''temperate'' climes between the frigid and the torrid ones. Different lists of climata were in use in Hellenistic and Roman time. Claudius Ptolemy was the first ancient scientist known to have devised the so-called system of seven climes (Almagest 2.12) which, due to his authority, became one of the canonical elements of late antique, medieval European and Arab geography. In Medieval Europe, the climes for 15 and 18 hours of longest daylig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Savannah
A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of grasses. Four savanna forms exist; ''savanna woodland'' where trees and shrubs form a light canopy, ''tree savanna'' with scattered trees and shrubs, ''shrub savanna'' with distributed shrubs, and ''grass savanna'' where trees and shrubs are mostly nonexistent.Smith, Jeremy M.B.. "savanna". Encyclopedia Britannica, 5 Sep. 2016, https://www.britannica.com/science/savanna/Environment. Accessed 17 September 2022. Savannas maintain an open canopy despite a high tree density. It is often believed that savannas feature widely spaced, scattered trees. However, in many savannas, tree densities are higher and trees are more regularly spaced than in forests.Manoel Cláudio da S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wet Season
The wet season (sometimes called the rainy season or monsoon season) is the time of year when most of a region's average annual rainfall occurs. Generally, the season lasts at least one month. The term ''green season'' is also sometimes used as a euphemism by tourist authorities. Areas with wet seasons are dispersed across portions of the tropics and subtropics. Under the Köppen climate classification, for tropical climates, a wet season month is defined as a month where average precipitation is or more. In contrast to areas with savanna climates and monsoon regimes, Mediterranean climates have wet winters and dry summers. Dry and rainy months are characteristic of tropical seasonal forests: in contrast to tropical rainforests, which do not have dry or wet seasons, since their rainfall is equally distributed throughout the year.Elisabeth M. Benders-Hyde (2003)World Climates.Blue Planet Biomes. Retrieved on 2008-12-27. Some areas with pronounced rainy seasons will see a break ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intertropical Convergence Zone
The Intertropical Convergence Zone (ITCZ , or ICZ), known by sailors as the doldrums or the calms because of its monotonous windless weather, is the area where the northeast and the southeast trade winds converge. It encircles Earth near the thermal equator though its specific position varies seasonally. When it lies near the geographic equator, it is called the near-equatorial trough. Where the ITCZ is drawn into and merges with a monsoon, monsoonal circulation, it is sometimes referred to as a ''monsoon trough'' (a usage that is more common in Australia and parts of Asia). Meteorology The ITCZ was originally identified from the 1920s to the 1940s as the ''Intertropical Front'' (''ITF''), but after the recognition in the 1940s and the 1950s of the significance of convergence zone, wind field convergence in tropics, tropical weather production, the term ''Intertropical Convergence Zone'' (''ITCZ'') was then applied. The ITCZ appears as a band of clouds, usually thunderstorms, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
