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In geography, the temperate or tepid climates of Earth occur in the middle latitudes, which span between the tropics and the polar regions of Earth.In most climate classifications, temperate climates refer to the climate zone between 35 and 50 north and south latitudes (between the subarctic and subtropical climates).
These zones generally have wider temperature ranges throughout the year and more distinct seasonal changes compared to tropical climates, where such variations are often small. They typically feature four distinct seasons, Summer the warmest, Autumn the transitioning season to Winter, the colder season, and Spring the transitioning season from winter back into summer. In the northern hemisphere, the year starts with winter, transitions in the first half year through spring into summer, which is in mid-year, then at the second half year through autumn into winter at year-end. In the southern hemisphere, the seasons are swapped, with summer between years and winter in mid-year.
The temperate zones (latitudes from 23.5° to the polar circles at about 66.5°, north and south) are where the widest seasonal changes occur, with most climates found in it having some influence from both the tropics and the poles. The subtropics (latitudes from about 23.5° to 35°, north and south) have temperate climates that have the least seasonal change and the warmest in winter, while at the other end, Boreal climates located from 55 to 65 north latitude have the most seasonal changes and long and severe winters.
In temperate climates, not only do latitudinal positions influence temperature changes, but sea currents, prevailing wind direction, continentality (how large a landmass is), and altitude also shape temperate climates.
The Köppen climate classification defines a climate as "temperate" when the mean temperature is above −3 °C (26.6 °F) but below 18 °C (64.4 °F) in the coldest month. However, other climate classifications set the minimum at 0 °C (32.0 °F).
The north temperate zone extends from (approximately 23.5° north) to the Arctic Circle (approximately 66.5° north latitude). The south temperate zone extends from (approximately 23.5° south) to the Antarctic Circle (approximately 66.5° south).
In some climate classifications, the temperate zone is often divided into several smaller climate zones, based on monthly temperatures, the coldest month, and rainfall. These include humid subtropical climate, Mediterranean climate, oceanic, and continental climate.
These are the climates that are typically found at southernmost portion of the temperate zone between 23.5° and 35° north or south, and thus are far more influenced by the tropics than any other tepid climate type, usually having warmer temperatures over the year, longer summers and mild, short winters. Freezing precipitation is uncommon in this portion of the temperate zone.
Humid Subtropical climates generally have long, hot and humid summers with convective showers in summer and a peak seasonal rainfall in the hottest months. Winters are normally mild in the humid subtropics, and warm ocean currents normally are found in coastal areas with humid subtropical climates. This type of climate is normally located along leeward lower east coast continents such as in southeast and central Argentina, Uruguay and south of Brazil, the southeast portions of East Asia, the southern United States, South Africa, and eastern Australia. In some areas with a humid subtropical climate (most notably southeast China and North India), there is an even sharper wet-dry season, called subtropical monsoon or Cwa. In these regions, winters are quite dry and summers have very heavy rainfall. Some Cwa areas in southern China reported more than 80% of annual precipitation in the 5 warmest months (Southwest Monsoon).
Mediterranean Climates, opposite to the humid subtropical and monsoonal climates, have a dry summer, with rainfall in the winter and cooler months. They occur mostly at the western edges and coasts of the continents and are bounded by arid deserts on their equatorward sides that cause the dry season of summer, and oceanic climates to the poleward sides that are influenced by cool ocean currents and air masses that bring the rainfall of winter. The five main Mediterranean regions of the world are the Mediterranean Sea basin in northwestern Afro-Eurasia, coastal California in the United States, the southwest of Argentina, the Western Cape of South Africa and the south and southwestern coast of Chile.
These are variants of the subtropical climates found in high altitude plateaus or montane systems either in the tropics or subtropics, they have characteristically mild temperatures year-round, featuring the four seasons in the subtropics and no marked seasons in the tropics, the latter usually remaining mild to cool through most of the year.
These occur in the middle latitudes, between 23°26'22" and 66°33'39" north, and 23°26'22" and 66°33'39" south and are the ones with the most of practically equal influence from the equator and the poles, and the most characteristic temperate climates with the typical distinct four season pattern. In these the temperatures remain relatively cool through most of the year as opposed to mild and warm in the subtropics and cold in the subpoles.
The oceanic climates are created by the onshore flow from the cool high latitude oceans to their west. This causes the climate to have cool summers and cool (but not cold) winters, and relative humidity and precipitation evenly distributed along the year. These climates are frequently cloudy, and are fairly milder both in winter and summer in comparison to other temperate climates. Annual rainfall is spread throughout the entire year. Regions with this climate include Northwestern Europe, Northwestern North America, southeastern and southwestern South America, southeastern Australia and most of New Zealand.
The continental climates, as opposed to the oceanic climates have strikingly extreme seasonal differences. With less moderating effect from ocean currents and more influence from tropical and polar large-size continental land air-masses they feature more extreme temperatures in each respective season, with summers getting as hot as those of subtropical or tropical climates and winters as cold as in subpolar climates. They are mostly found on the northern hemisphere, because this is where there is a large enough landmass to generate extremes in seasonal temperatures, however some areas of Patagonia experience continental climate as well. This climate type is found in northeast Asia, the north-central and north- eastern United States and southern Canada, and Eurasia, in eastern, central and northern Europe, in Patagonia and in mountains of Cuyo.
These are temperate climates that opposite to the subtropicals are on the poleward edge of the temperate zone, therefore still have four marked seasons including a warmer one, but are far more influenced by the poles than any other but the very polar climates (Tundra and Icecap).
Areas with subpolar oceanic climates feature an oceanic climate but are usually located closer to polar regions. As a result of their location, these regions tend to be on the cool end of oceanic climates. Snowfall tends to be more common here than in other oceanic climates. Subpolar oceanic climates are less prone to temperature extremes than subarctic climates or continental climates, featuring milder winters than these climates. This variant of an oceanic climate is found in parts of coastal Iceland, the Faroe Islands, parts of Scotland, northwestern coastal areas of Norway such as Lofoten and reaching to 70°N on some islands, uplands near the coast of southwestern Norway, the Aleutian Islands of Alaska and northern parts of the Alaskan Panhandle, some parts of Southern Argentina and Chile (though most regions still fall as continental subantarctic), and a few highland areas of Tasmania, and the Australian and Southern Alps. This type of climate is even found in the very remote parts of the Papuan Highlands in Indonesia. The classification used for this regime is Cfc. In the most marine of those areas affected by this regime, temperatures above 20 °C (68 °F) are extreme weather events, even in the midst of summer. Temperatures above 30 °C (86 °F) have been recorded on rare occasions in some areas of this climate, and in winter temperatures down to −20 °C (−4 °F) have seldom been recorded in some areas.
Mostly polewards of Humid Continental zones this climate features extremely cold and long winters, with short mild summers. In very small areas at high altitudes around the Mediterranean Basin, Iran, Kyrgyzstan, Tajikistan, Turkey, Alaska and other parts of the northwestern United States (Eastern Washington, Eastern Oregon and Southern Idaho) and Russian South-Eastern regions the climate is classified as Dsc with a dry summer climate, such as in Seneca, Oregon or Atlin, British Columbia. In the Southern Hemisphere it is found in southern Patagonia (cities like Rio Grande and Tolhuin). This is the closest to the polar climates of all four-season temperate climates, as practically all of the year is set up by extremely low temperatures, except for summer.
The vast majority of the world's human population resides in temperate zones, especially in the northern hemisphere, due to its greater mass of land.The biggest described number in temperate region in the world is found in southern Africa, where some 24,000 taxa (species and infraspecific taxa) have been described, but the native fauna and flora of this region does not have much cultural importance for the majority of the human population of the world that lives in Temperate Zones and that live in the Northern Hemisphere, only environmental importance.
Farming is a large-scale practice in the temperate regions (except for Boreal/Subarctic regions) due to the plentiful rainfall and warm summers, because most agricultural activity occurs in the spring and summer, cold winters have a small effect on agricultural production. Extreme winters or summers have a huge impact on the productivity of agriculture.
Temperate regions have the majority of the world's population, which leads to large cities. There are a couple factors why the climate of large city landscapes differs from the climate of rural areas. One factor is the strength of the absorption rate of builds and asphalt, which is higher than natural land. The other large factor is the burning of fossil fuels from buildings and vehicles. These factors have led to the average climate of cities to be warmer than surrounding areas.
"Temperate Climate" refers to climates between Polar and Tropical. However, there is a gradual change from polar to tropical climates across the middle latitude temperate zones. Normally, in the northern hemisphere, the northern portions of the temperate zone feature Boreal, Continental, and Oceanic climates, while the southern portions of the temperate zone are often Mediterranean and humid subtropical climates. These different climates all fall within the temperate zone which has a basic definition as being any climate with a mean temperature above −3 °C (26.6 °F) but below 18 °C (64.4 °F) in the coldest month. Obviously winter temperatures will be more mild in southerly portions and colder in the more northerly portions of the northern temperate zone and vice-versa in the southern temperate zone.
From a floristic standpoint, each of these climate zones have generally temperate vegetation. There is however, an obvious change in flora from the far northern portions of the temperate zone (Boreal) to the far southern portion (humid subtropical). Pines and conifers are endemic and more abundant in the northern portion of the temperate, while palms may be endemic to far southern portions of the temperate zone. Along with this, the humid subtropical climate may be wrongly separated from the Temperate group of climates, and further associated with the Tropical climates, much because of its name, temperatures and the vegetation found in Subtropical zones which can be somewhat similar to that of Tropical regions (For instance the Atlantic Forest of Brazil is spread across both Temperate and Tropical zones of the country). Additionally, both temperate and tropical species can be found side by side in the far southern portions of the temperate zone (for example in central Florida), while subarctic species might be found growing in northern portions of the continental zone (for example in Northwest Europe).
Climate is the long-term average of weather, typically averaged over a period of 30 years. Some of the meteorological variables that are commonly measured are temperature, humidity, atmospheric pressure, wind, and precipitation. In a broader sense, climate is the state of the components of the climate system, which includes the ocean and ice on Earth. The climate of a location is affected by its latitude, terrain, and altitude, as well as nearby water bodies and their currents.
Nigeria is a country in West Africa. Nigeria shares land borders with the Republic of Benin in the west, Chad and Cameroon in the east, and Niger in the north. It also shares a border with the self-declared, but internationally unrecognized state of Ambazonia in the southeast. Its coast lies on the Gulf of Guinea in the south and it borders Lake Chad to the northeast. In the southeast, it also shares a border with the breakaway state of Ambazonia. Noted geographical features in Nigeria include the Adamawa highlands, Mambilla Plateau, Jos Plateau, Obudu Plateau, the Niger River, River Benue and Niger Delta.
The subarctic climate is a climate characterised by long, usually very cold winters, and short, cool to mild summers. It is found on large landmasses, away from the moderating effects of an ocean, generally at latitudes from 50° to 70°N poleward of the humid continental climates. Subarctic or boreal climates are the source regions for the cold air that affects temperate latitudes to the south in winter. These climates represent Köppen climate classification Dfc, Dwc, Dsc, Dfd, Dwd and Dsd.
The tropics are the region of the Earth surrounding the Equator. They are delimited in latitude by the Tropic of Cancer in the Northern Hemisphere at 23°26′11.9″ (or 23.43664°) N and the Tropic of Capricorn in the Southern Hemisphere at 23°26′11.9″ (or 23.43664°) S; these latitudes correspond to the axial tilt of the Earth. The tropics are also referred to as the tropical zone and the torrid zone. The tropics include all the areas on the Earth where the Sun contacts a point directly overhead at least once during the solar year - thus the latitude of the tropics is roughly equal to the angle of the Earth's axial tilt.
A Mediterranean climate or dry summer climate is characterized by dry summers and mild, wet winters. The climate receives its name from the Mediterranean Basin, where this climate type is most common. Mediterranean climate zones are typically located along the western sides of continents, between roughly 30 and 45 degrees north and south of the equator. The main cause of Mediterranean, or dry summer climate, is the subtropical ridge which extends northwards during the summer and migrates south during the winter due to increasing north-south temperature differences.
The subtropics are geographic and climate zones located roughly between the tropics at latitude 23° 27' and the temperate zones, north and south of the Equator.
The Köppen climate classification is one of the most widely used climate classification systems. It was first published by the German-Russian climatologist Wladimir Köppen (1846–1940) in 1884, with several later modifications by Köppen, notably in 1918 and 1936. Later, the climatologist Rudolf Geiger introduced some changes to the classification system, which is thus sometimes called the Köppen–Geiger climate classification system.
An oceanic climate, also known as a marine climate or temperate oceanic climate, is the Köppen classification of climate typical of west coasts in higher middle latitudes of continents, and generally features cool summers and cool but not cold winters, with a relatively narrow annual temperature range and few extremes of temperature. Oceanic climates are defined as having a monthly mean temperature below 22 °C (72 °F) in the warmest month, and above 0 °C (32 °F) in the coldest month. This climate type is often caused by the onshore flow from the cool, high latitude oceans that are found west of their location.
A semi-arid climate or steppe climate is the climate of a region that receives precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-arid climates, depending on variables such as temperature, and they give rise to different biomes.
A humid continental climate is a climatic region defined by Russo-German climatologist Wladimir Köppen in 1900, typified by four distinct seasons and large seasonal temperature differences, with warm to hot summers and cold winters. Precipitation is usually distributed throughout the year. The definition of this climate regarding temperature is as follows: the mean temperature of the coldest month must be below −3 °C (26.6 °F) and there must be at least four months whose mean temperatures are at or above 10 °C (50 °F). In addition, the location in question must not be semi-arid or arid. The Dfb, Dwb and Dsb subtypes are also known as hemiboreal.
The geography of South America contains many diverse regions and climates. Geographically, South America is generally considered a continent forming the southern portion of the landmass of the Americas, south and east of the Panama–Colombia border by most authorities, or south and east of the Panama Canal by some. South and North America are sometimes considered a single continent or supercontinent, while constituent regions are infrequently considered subcontinents.
The five main latitude regions of the Earth's surface comprise geographical zones, divided by the major circles of latitude. The differences between them relate to climate. They are as follows:
Australia's climate is governed mostly by its size and by the hot, sinking air of the subtropical high pressure belt. This moves north-west and north-east with the seasons. The climate is variable, with frequent droughts lasting several seasons, thought to be caused in part by the El Niño-Southern Oscillation. Australia has a wide variety of climates due to its large geographical size. The largest part of Australia is desert or semi-arid. Only the south-east and south-west corners have a temperate climate and moderately fertile soil. The northern part of the country has a tropical climate, varying between grasslands and desert. Australia holds many heat-related records: the continent has the hottest extended region year-round, the areas with the hottest summer climate, and the highest sunshine duration.
The climate in Brazil varies considerably mostly from tropical north to temperate zones south of the Tropic of Capricorn.
The climate of the United States varies due to changes in latitude, and a range of geographic features, including mountains and deserts. Generally, on the mainland, the climate of the U.S. becomes warmer the further south one travels, and drier the further west, until one reaches the West Coast.
The climate of Mexico is very varied. The Tropic of Cancer effectively divides the country into temperate and tropical zones. Land that is north of the twenty-fourth parallel experiences lower temperatures during the winter months. South of the twenty-fourth parallel, temperatures are fairly consistent all year round and vary solely as a function of elevation. The north of the country usually receives less precipitation than the south.
Vietnam's climate, being located in the tropics and strongly influenced by the South China Sea has a monsoon-influenced tropical climate typical of that of mainland Southeast Asia. In the north, the climate is monsoonal with four distinct seasons while in the south, the climate is tropical monsoon with two seasons. In addition temperate climate exists in mountainous areas, which are found in Sa Pa, Da Lat while a more continental climate exists in Lai Chau Province and Son La Province. The diverse topography, wide range of latitudes, and influences from the South China Sea lead to climatic conditions varying significantly between regions. 20% of Vietnam's total surface area is low-elevation coastal area making the country highly vulnerable to climate change effects and the rising sea levels in particular.
A humid subtropical climate is a zone of climate characterized by hot and humid summers, and cold to mild winters. These climates normally lie on the southeast side of all continents, generally between latitudes 25° and 35° and are located poleward from adjacent tropical climates.
A season is a division of the year marked by changes in weather, ecology, and the amount of daylight. On Earth, seasons are the result of Earth's orbit around the Sun and Earth's axial tilt relative to the ecliptic plane. In temperate and polar regions, the seasons are marked by changes in the intensity of sunlight that reaches the Earth's surface, variations of which may cause animals to undergo hibernation or to migrate, and plants to be dormant. Various cultures define the number and nature of seasons based on regional variations.
Earth rainfall climatology Is the study of rainfall, a sub-field of Meteorology. Formally, a wider study includes water falling as ice crystals, i.e. hail, sleet, snow. The aim of rainfall climatology is to measure, understand and predict rain distribution across different regions of planet Earth, a factor of air pressure, humidity, topography, cloud type and raindrop size, via direct measurement and remote sensing data acquisition. Current technologies accurately predict rainfall 3–4 days in advance using numerical weather prediction. Geostationary orbiting satellites gather IR and visual wavelength data to measure realtime localised rainfall by estimating cloud albedo, water content, and the corresponding probability of rain. Geographic distribution of rain is largely governed by climate type, topography and habitat humidity. In mountainous areas, heavy precipitation is possible where upslope flow is maximized within windward sides of the terrain at elevation. On the leeward side of mountains, desert climates can exist due to the dry air caused by compressional heating. The movement of the monsoon trough, or intertropical convergence zone, brings rainy seasons to savannah climes. The urban heat island effect leads to increased rainfall, both in amounts and intensity, downwind of cities. Warming may also cause changes in the precipitation pattern globally, including wetter conditions at high latitudes and in some wet tropical areas. Precipitation is a major component of the water cycle, and is responsible for depositing most of the fresh water on the planet. Approximately 505,000 cubic kilometres (121,000 cu mi) of water falls as precipitation each year; 398,000 cubic kilometres (95,000 cu mi) of it over the oceans. Given the Earth's surface area, that means the globally averaged annual precipitation is 990 millimetres (39 in). Climate classification systems such as the Köppen climate classification system use average annual rainfall to help differentiate between differing climate regimes.