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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.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. On the northern hemisphere the year starts with winter, transitions in the first halfyear through spring into summer which is in mid-year, then at the second halfyear through autumn into winter at year-end. On the southern hemisphere seasons are swapped with summer in between years and winter in mid-year.
Geography is a field of science devoted to the study of the lands, features, inhabitants, and phenomena of the Earth and planets. The first person to use the word γεωγραφία was Eratosthenes. Geography is an all-encompassing discipline that seeks an understanding of Earth and its human and natural complexities—not merely where objects are, but also how they have changed and come to be.
Earth is the third planet from the Sun, and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago. Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.
The middle latitudes of Earth lie between 23°26'22" and 66°33'39" north, and between 23°26'22" and 66°33'39" south. They include Earth's subtropical temperate zones, which lie between the tropics and the polar circles. Weather fronts and extratropical cyclones are usually found in this area, as well as occasional tropical cyclones, which have traveled from their areas of formation closer to the Equator.
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.
A polar circle is either the Arctic Circle or the Antarctic Circle. On Earth, the Arctic Circle is located at a latitude of 66°33′47.5″ N, and the Antarctic Circle is located at a latitude of 66°33′47.5″ S.
The Arctic Circle is one of the two polar circles and the most northerly of the five major circles of latitude as shown on maps of Earth. It marks the northernmost point at which the centre of the noon sun is just visible on the December solstice and the southernmost point at which the centre of the midnight sun is just visible on the June solstice. The region north of this circle is known as the Arctic, and the zone just to the south is called the Northern Temperate Zone.
The Antarctic Circle is the most southerly of the five major circles of latitude that mark maps of the Earth. The region south of this circle is known as the Antarctic, and the zone immediately to the north is called the Southern Temperate Zone. South of the Antarctic Circle, the sun is above the horizon for 24 continuous hours at least once per year and the centre of the sun is below the horizon for 24 continuous hours at least once per year ; this is also true within the equivalent polar circle in the Northern Hemisphere, the Arctic Circle.
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, in more recent climate classifications climatologists use the 0 °C (32.0 °F) line .
The Köppen climate classification is one of the most widely used climate classification systems. It was first published by the 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.
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 (at 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.
A humid subtropical climate is a zone of climate characterized by hot and humid summers, and cool to mild winters. These climates normally lie on the southeast side of all continents, generally between latitudes 25° and 40° and are located poleward from adjacent tropical climates. While many subtropical climates tend to be located at or near coastal locations, in some cases they extend inland, most notably in China and the United States, where they exhibit more pronounced seasonal variations and sharper contrasts between summer and winter, as part of a gradient between the more tropical climates of the southern coasts of these countries and the more continental climates of China and the United States’ northern and central regions.
A Mediterranean climate or dry summer climate is characterized by rainy winters and dry summers, with less than 40 mm of precipitation for at least three summer months. While the climate receives its name from the Mediterranean Basin, these are generally located on the western coasts of continents, between roughly 30 and 45 degrees north and south of the equator, typically between oceanic climates towards the poles, and semi-arid and arid climates towards the equator.
An oceanic climate, also known as a marine climate or maritime climate, is the Köppen classification of climate typical of west coasts in higher middle latitudes of continents, and generally features mild summers and mild winters, with a relatively narrow annual temperature range and few extremes of temperature, with the exception for transitional areas to continental, subarctic and highland climates. 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.
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 precipatation is less common in this portion of the temperate zone.
Humid Subtropical climates generally have no marked dry season with rainfall and relative humidity evenly distributed over the year, influenced by Humid Tropical regions and by warm ocean currents. They are predominant on the leeward southeastern corners of the continents such as in southeast of South America (Argentina, Uruguay and Brazil), China, The United States, South Africa, eastern Australia and parts of southern Europe namely the Pó Valley of northern Italy.
A tropical rainforest climate is a tropical climate usually found within 10 to 15 degrees latitude of the equator, and has at least 60 mm of rainfall every month of the year. Regions with this climate are typically designated Af by the Köppen climate classification. A tropical rainforest climate is typically hot and wet.
South America is a continent in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. It may also be considered a subcontinent of the Americas, which is how it is viewed in the Spanish and Portuguese-speaking regions of the Americas. The reference to South America instead of other regions has increased in the last decades due to changing geopolitical dynamics.
Argentina, officially the Argentine Republic, is a country located mostly in the southern half of South America. Sharing the bulk of the Southern Cone with Chile to the west, the country is also bordered by Bolivia and Paraguay to the north, Brazil to the northeast, Uruguay and the South Atlantic Ocean to the east, and the Drake Passage to the south. With a mainland area of 2,780,400 km2 (1,073,500 sq mi), Argentina is the eighth-largest country in the world, the fourth largest in the Americas, and the largest Spanish-speaking nation. The sovereign state is subdivided into twenty-three provinces and one autonomous city, Buenos Aires, which is the federal capital of the nation as decided by Congress. The provinces and the capital have their own constitutions, but exist under a federal system. Argentina claims sovereignty over part of Antarctica, the Falkland Islands, and South Georgia and the South Sandwich Islands.
Monsoonal Subtropical climates are the ones with a marked winter dry/drier season with rainfall usually in the warmest months with the coming of monsoons from humid tropical zones. Are usually found at the edges of predominantly Humid Subtropical regions nearby Arid and Semi-Arid climates, less influenced by the humid tropics and warm oceans, such as southeastern China and Northern India or High altitude areas in the Tropical and Subtropical zone, such as the highlands of Mexico, South America and Sub-saharan Africa
Mediterranean Climates, opposite to the monsoonal variety have a dry summer, with rainfall on 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 warm and humid 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, the west coast of North America specially California, the southwest of South America namely Argentina and Chile, the Western Cape of South Africa and the south and southwestern coast of Australia.
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 35° and 55° north and 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 almost exclusively found only on the northern hemisphere, because this is where there is a large enough landmass to generate extremes in seasonal temperatures. 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.
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, the far south of Chile and Argentina, 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 north 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. 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 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).
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. Its coast lies on the Gulf of Guinea in the south and it borders Lake Chad to the northeast. 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. These climates represent Köppen climate classification Dfc, Dwc, Dsc, Dfd, Dwd and Dsd. In very small areas at high altitudes around the Mediterranean Basin, Iran, Kyrgyzstan, Tajikistan, Turkey, Alaska and other parts of the northwestern United States 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.
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′12.4″ (or 23.43678°) N and the Tropic of Capricorn in the Southern Hemisphere at 23°26′12.4″ (or 23.43678°) 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.
The subtropics are geographic and climate zones located roughly between the tropics at latitude 23.5° and temperate zones north and south of the Equator.
A tropical climate in the Köppen climate classification is a non-arid climate in which all twelve months have mean temperatures of warmer than 18 °C (64 °F). In tropical climates there are often only two seasons: a wet season and a dry season. Tropical climates are frost-free, and changes in the solar angle are small. In tropical climates, the temperature remains relatively constant (hot) throughout the year. Sunlight is intense.
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 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:
The climate of the United States varies due to differences 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 highly varied. The Tropic of Cancer effectively divides the country into temperate and tropical zones. Land north of the twenty-fourth parallel experiences lower temperatures during the winter months. South of the twenty-fourth parallel, temperatures are fairly constant year round and vary solely as a function of elevation. The north of the country generally 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 season is a division of the year marked by changes in weather, ecology, and amount of daylight. On Earth, seasons result from 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. Global warming may also cause changes in the precipitation pattern globally, including wetter conditions at high latitudes and in some wet tropical areas, and drier conditions in parts of the subtropics and middle latitudes. 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.
The climate in Spain varies across the country. Spain is the most climatically diverse country in Europe with 13 different Köppen climates, excluding the Canary Islands, and is within the 10 most climatically diverse countries in the world. Five main climatic zones can be distinguished, according to Guzman geographical situation and orographic conditions: