Worldwide climate classifications

Climate is the average and variations of weather in a region over long periods of time. The weather is a set of all the phenomena occurring in a given Atmosphere at a given Time. The climate of a location is affected by its latitude, terrain, persistent ice or snow cover, as well as nearby oceans and their currents. Climates can be classified using parameters such as temperature and rainfall to define specific climate types. Climate classification systems are ways of classifying the world's Climates A climate classification may correlate closely with a Biome category as climate is a major The most commonly used classification scheme is the one originally developed by Wladimir Koeppen. Wladimir Peter Köppen (Владимир Петрович Кёппен (born September 25, 1846 in Saint Petersburg, Russia &mdash died The Thornthwaite system, in use since 1948, incorporates evapotranspiration in addition to temperature and precipitation information and is used in studying animal species diversity and potential impacts of climate changes. Evapotranspiration (ET is a term used to describe the sum of Evaporation and Plant Transpiration from the earth's land surface to Atmosphere Climate change is any long-term significant change in the “average weather” that a given region experiences The Bergeron and Spatial Synoptic Classification systems focus on the origin of air masses defining the climate for certain areas. Based upon the Bergeron Air mass classification scheme is the Spatial Synoptic Classification system, or SSC

Paleoclimatology is the study and description of ancient climates using information from both non-biotic factors such as sediments found in lake beds and ice cores, and biotic factors such as tree rings and coral, and can be used to extend back the temperature or rainfall information for particular locations to a time before various weather instruments were used to monitor weather conditions. Paleoclimatology (also Palaeoclimatology) is the study of Climate change taken on the scale of the entire History of Earth. Climate models are mathematical models of past, present and future climates and can be used to describe the likely patterns of future changes. This article is about the theories and mathematics of climate modeling

Definition

Climate (from Ancient Greek klima) is commonly defined as the weather averaged over a long period of time. Nature, in the broadest sense is equivalent to the natural world, physical universe, material world or material universe. The weather is a set of all the phenomena occurring in a given Atmosphere at a given Time. A season is one of the major divisions of the Year, generally based on yearly periodic changes in Weather. Spring is one of the four Temperate Seasons Spring marks the transition from Winter into Summer. Summer is one of the four Temperate Seasons Summer marks the warmest time of year with the longest days Autumn (also known as fall in North American English) is one of the four Temperate Seasons Autumn marks the transition from Summer Winter is one of the four Seasons of Temperate zones Calculated astronomically, it begins on the Solstice and ends on the Equinox The Tropics are centered on the Equator and limited in Latitude by the Tropic of Cancer in the northern hemisphere at approximately 23°26' (23 The dry season is a term commonly used when describing the weather in the Tropics. A wet season or rainy season is a Season in which the average Rainfall in a region is significantly increased A storm is any disturbed state of an astronomical body's atmosphere, especially affecting its surface and strongly implying Severe weather. A tornado is a violent rotating column of air which is in contact with both the surface of the earth and a Cumulonimbus cloud or in rare cases the base of a Cumulus A tropical cyclone is a storm system characterized by a low pressure center and numerous Thunderstorms that produce strong winds and Flooding Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are a group of Cyclones defined as synoptic scale low A winter storm is an event in which the dominant varieties of precipitation are forms that only occur at cold Temperatures such as Snow or A blizzard is a severe Winter storm condition characterized by low Temperatures strong Winds and heavy blowing Snow Blizzards are formed when An ice storm is a type of Winter storm characterized by Freezing rain. In Meteorology, precipitation (also known as one class of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric Fog is a cloud that is in contact with the ground Stratus clouds are usually the only clouds that touch the ground Drizzle (also called mizzle) is light precipitation consisting of liquid water drops smaller than that of Rain, and generally smaller than 0 Rain is Liquid precipitation. On Earth it is the condensation of atmospheric Water vapor into drops heavy enough to fall often making it to Freezing rain is a type of precipitation that begins as Snow at higher altitude falling from a Cloud towards earth melts completely on its way down while passing Ice pellets are a form of precipitation consisting of small Translucent ice balls Hail is a form of precipitation which consists of balls or irregular lumps of ice (hailstones "Snowfall" redirects here For other uses see Snow (disambiguation or Snowfall (disambiguation. Graupel (also called snow pellets) refers to precipitation that forms when supercooled Droplets of Water condense on a Snowflake forming This is a list of meteorology topics. The terms relate to Meteorology, the Interdisciplinary scientific study of the atmosphere that focuses on Meteorology (from Greek grc μετέωρος metéōros, "high in the sky" and grc -λογία -logia) is the Interdisciplinary Weather forecasting is the application of science and technology to predict the state of the atmosphere for a future time and a given location Air pollution is the human introduction into the atmosphere of Chemicals Particulate matter, or Biological materials that cause harm or discomfort The Ancient Greek language is the historical stage in the development of the Hellenic language family spanning the Archaic (c ^[1] The standard averaging period is 30 years,^[2] but other periods may be used depending on the purpose. Climate also includes statistics other than the average, such as the magnitudes of day-to-day or year-to-year variations. The Intergovernmental Panel on Climate Change (IPCC) glossary definition is:

Climate in a narrow sense is usually defined as the “average weather”, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The classical period is 30 years, as defined by the World Meteorological Organization (WMO). These quantities are most often surface variables such as temperature, precipitation, and wind. Climate in a wider sense is the state, including a statistical description, of the climate system. ^[3]

The difference between climate and weather is usefully summarized by the popular phrase "Climate is what you expect, weather is what you get. "^[4] Over historical time spans there are a number of static variables that determine climate, including latitude, altitude, proportion of land to water, and proximity to oceans and mountains. History is the study of the past particularly the written record Those who study history as a Profession are called Historians Etymology Other climate determinants are more dynamic: for example, the thermohaline circulation of the ocean leads to a 5 °C (9 °F) warming of the northern Atlantic ocean compared to other ocean basins. The term thermohaline circulation (THC refers to the part of the large-scale ocean circulation that is thought to be driven by global density gradients created by surface heat and ^[5] Other ocean currents redistribute heat between land and water on a more regional scale. An ocean current is continuous directed movement of Ocean water. The density and type of vegetation coverage affects solar heat absorption,^[6] water retention, and rainfall on a regional level. Alterations in the quantity of atmospheric greenhouse gases determines the amount of solar energy retained by the planet, leading to global warming or global cooling. Greenhouse gases are gaseous constituents of the atmosphere bothnatural and anthropogenic that absorb and emit radiation at specific wavelengths within the spectrum of thermal infrared Global warming is the increase in the average measured temperature of the Global cooling in general can refer to an overall cooling of the Earth. The variables which determine climate are numerous and the interactions complex, but there is general agreement that the broad outlines are understood, at least insofar as the determinants of historical climate change are concerned. ^[7]

Climate classification

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. The seven climes ( klima, plural klimata, meaning "inclination" referring to the angle between the axis of the Celestial sphere and the horizon The term ancient Greece refers to the period of Greek history lasting from the Greek Dark Ages ca 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 weather disturbances. For airmass in Astronomy, see Airmass. In Meteorology, an air mass is a large volume of Air that Examples of empiric classifications include climate zones defined by plant hardiness,^[8] evapotranspiration,^[9] air mass origin, or more generally the Köppen climate classification which was originally designed to identify the climates associated with certain biomes. The Köppen climate classification is one of the most widely used climate classification systems It was developed by Wladimir Köppen, a German climatologist A common shortcoming of these classification schemes is that they produce distinct boundaries between the zones they define, rather than the gradual transition of climate properties more common in nature.

Bergeron and Spatial Synoptic

Source regions of global air masses

Main article: Air mass

The most generic classification is that involving the concept of air masses. For airmass in Astronomy, see Airmass. In Meteorology, an air mass is a large volume of Air that The Bergeron classification is the most widely accepted form of air mass classification. Air mass classification involves three letters. The first letter describes its moisture properties, with c used for continental air masses (dry) and m for maritime air masses (moist). The second letter describes the thermal characteristic of its source region: T for tropical, P for polar, A for Arctic or Antarctic, M for monsoon, E for equatorial, and S for superior air (dry air formed by significant downward motion in the atmosphere). The third letter is used to designate the stability of the atmosphere. If the air mass is colder than the ground below it, it is labeled k. If the air mass is warmer than the ground below it, it is labeled w. ^[10] While air mass identification was originally used in weather forecasting during the 1950s, climatologists began to establish synoptic climatologies based on this idea in 1973. Weather forecasting is the application of science and technology to predict the state of the atmosphere for a future time and a given location ^[11]

Based upon the Bergeron classification scheme is the Spatial Synoptic Classification (SSC) system. There are six categories within the SSC scheme: Dry Polar (similar to continental polar), Dry Moderate (similar to maritime superior), Dry Tropical (similar to continental tropical), Moist Polar (similar to maritime polar), Moist Moderate (a hybrid between maritime polar and maritime tropical), and Moist Tropical (similar to maritime tropical, maritime monsoon, or maritime equatorial). ^[12]

Köppen

Annual average surface temperatures from 1961–1990. This is an example of how climate varies with location.

Main article: Köppen climate classification

The Köppen classification includes climate regimes such as Rain forest, monsoon, tropical savanna, humid subtropical, humid continental, oceanic climate, Mediterranean climate, continental steppe, subarctic climate, tundra, polar ice cap, and desert. The Köppen climate classification is one of the most widely used climate classification systems It was developed by Wladimir Köppen, a German climatologist Rainforests are Forests characterized by high Rainfall with definitions setting minimum normal annual rainfall between 1750–2000 mm (68-78 inches A monsoon is a seasonal prevailing wind which lasts for several months Tropical and subtropical grasslands savannas and shrublands are a Grassland Biome located in Semi-arid to semi- Humid Climate regions Humid subtropical climate ( Köppen Cfa or Cwa) is a climate zone characterized by hot humid summers and chilly to mild winters The humid continental climate is a Climate found over large areas of land masses in the temperate regions of the mid-latitudes where there is a zone of conflict between An oceanic climate (also called marine west coast climate and maritime climate) is the Climate typically found along the west coasts at the middle latitudes A Mediterranean climate is one that resembles the Climate of the lands in the Mediterranean Basin, which includes over half of the area with this climate type world-wide In physical Geography, a steppe ( German, from степь - "a flat and arid land" степ - /stɛp/ тал - tal дала - /dɑlɑ/ pronounced Regions having a subarctic climate (also called boreal climate) are characterized by long usually very cold winters and brief warm summers In physical Geography, tundra is an area where the Tree growth is hindered by low temperatures and short growing seasons A polar ice cap is a high- Latitude region of a Planet or moon that is covered in Ice. A desert is a Landscape or region that receives very little precipitation. Rain forests are characterized by high rainfall, with definitions setting minimum normal annual rainfall between 1,750 millimetres (69 in) and 2,000 millimetres (79 in). Rain is Liquid precipitation. On Earth it is the condensation of atmospheric Water vapor into drops heavy enough to fall often making it to Mean monthly temperatures exceed 18 °C (64 °F) during all months of the year. ^[13] A monsoon is a seasonal prevailing wind which lasts for several months, ushering in a region's rainy season. ^[14] Regions such as within North America, South America. South America is a Continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a Sub-Saharan Africa, Australia and East Asia to qualify as monsoon regimes. Sub-Saharan Africa is a geographical term used to describe the area of the African continent which lies south of the Sahara, or those African countries For a topic outline on this subject see List of basic Australia topics. The East Asian monsoon is a Monsoonal flow that carries moist air from the Indian Ocean and Pacific Ocean to East Asia. ^[15] A tropical savanna is a grassland biome located in semi-arid to semi-humid climate regions of subtropical and tropical latitudes, with average temperatures remain at or above 18 °C (64 °F) year round and rainfall between 750 millimetres (30 in) and 1,270 millimetres (50 in) a year. Grasslands (also called greenswards) are areas where the Vegetation is dominated by Grasses ( Poaceae) and other Herbaceous (non-woody A biome is a climatically and geographically defined area of ecologically similar climatic conditions such as communities of Plants Animals and A Semi-arid climate or steppe climate generally describes climatic regions that receive low annual Rainfall (250-500 mm or 10-20 in Humidity is the amount of water vapor in the air In daily language the term "humidity" is normally taken to mean Relative humidity. The subtropics are the zones of the Earth immediately north and south of the tropic zone which is bounded by the Tropic of Cancer and the Tropic of The Tropics are centered on the Equator and limited in Latitude by the Tropic of Cancer in the northern hemisphere at approximately 23°26' (23 Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the They are widespread on Africa, and are also found in India, the northern parts of South America, Malaysia, and Australia. India, officially the Republic of India (भारत गणराज्य inc-Latn Bhārat Gaṇarājya; see also other Indian languages) is a country South America is a Continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a For the biogeographical region see Malesia Malaysia (məˈleɪʒə or /məˈleɪziə/ is a country that consists of thirteen states and For a topic outline on this subject see List of basic Australia topics. ^[16] The humid subtropical climate zone where winter rainfall (and sometimes snowfall) is associated with large storms that the westerlies steer from west to east. "Snowfall" redirects here For other uses see Snow (disambiguation or Snowfall (disambiguation. A storm is any disturbed state of an astronomical body's atmosphere, especially affecting its surface and strongly implying Severe weather. The Westerlies or the Prevailing Westerlies are the prevailing winds in the Middle latitudes between 30 and 60 degrees Latitude, blowing from Most summer rainfall occurs during thunderstorms and from occasional tropical cyclones. A tropical cyclone is a storm system characterized by a low pressure center and numerous Thunderstorms that produce strong winds and Flooding ^[17] Humid subtropical climates lie on the east side continents, roughly between latitudes 20° and 40° degress away from the equator. Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the ^[18]

Humid continental climate worldwide

Humid continental climate is marked by variable weather patterns and a large seasonal temperature variance. The humid continental climate is a Climate found over large areas of land masses in the temperate regions of the mid-latitudes where there is a zone of conflict between Places with a hottest monthly temperature above 10 °C (50 °F) and a coldest month temperature below −3 °C (26. 6 °F) and which do not meet the criteria for an arid climate, are classified as continental. In general terms the Climate of a local or region is said to be arid when it is characterized by a severe lack of available Water, to the extent of hindering ^[19] An oceanic climate is typically found along the west coasts at the middle latitudes of all the world's continents, and in southeastern Australia, and is accompanied by plentiful precipitation year round. For a topic outline on this subject see List of basic Australia topics. ^[20] The Mediterranean climate regime resembles the climate of the lands in the Mediterranean Basin, parts of western North America, parts of Western and South Australia, in southwestern South Africa and in parts of central Chile. The Mediterranean Basin refers to the lands around and surrounded by the Mediterranean Sea. Western Australia is a state occupying the entire western third of the Australian continent. South Australia is a state of Australia in the southern central part of the country The Republic of South Africa (also known by other official names) is a country located at the southern tip of the continent of Africa Chile, officially the Republic of Chile ( Spanish:) is a country in South America occupying a long and narrow Coastal strip wedged between the The climate is characterized by hot, dry summers and cool, wet winters. ^[21] A steppe is a dry grassland with an annual temperature range in the summer of up to 40 °C (104 °F) and during the winter down to −40 °C (−40. In physical Geography, a steppe ( German, from степь - "a flat and arid land" степ - /stɛp/ тал - tal дала - /dɑlɑ/ pronounced Grasslands (also called greenswards) are areas where the Vegetation is dominated by Grasses ( Poaceae) and other Herbaceous (non-woody 0 °F). ^[22] A subarctic climate has little precipitation,^[23] and monthly temperatures which are above 10 °C (50 °F) for one to three months of the year, with continuous permafrost due to the very cold winters. Regions having a subarctic climate (also called boreal climate) are characterized by long usually very cold winters and brief warm summers This article is about frozen ground For other meanings see Permafrost (disambiguation. Winters within subarctic climates include up to six months of temperatures averaging below 0 °C (32 °F). ^[24]

Map of arctic tundra

Arctic tundra occurs in the far Northern Hemisphere, north of the taiga belt, including vast areas of northern Russia and Canada ^[25]. Northern Hemisphere is the half of a Planet that is North of the Equator —the word hemisphere literally means 'half ball' Taiga (ˈtaɪgə from Turkic or Mongolian) is a Biome characterized by Coniferous forests Russia (Россия Rossiya) or the Russian Federation ( Rossiyskaya Federatsiya) is a transcontinental Country extending Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page A polar ice cap, or polar ice sheet, is a high-latitude region of a planet or moon that is covered in ice. Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the A planet, as defined by the International Astronomical Union (IAU is a celestial body Orbiting a Star or stellar remnant that is A natural satellite or moon is a Celestial body that Orbits a Planet or smaller body which is called the primary. Ice is a Solid phase, usually crystalline, of a Non-metalic substance that is liquid or gas at Room temperature, such as Ammonia Ice caps form because high-latitude regions receive less energy in the form of solar radiation from the sun than equatorial regions, resulting in lower surface temperatures. Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the The Sun (Sol is the Star at the center of the Solar System. The equator (sometimes referred to colloquially as "the Line") is the intersection of the Earth 's surface with the plane perpendicular to the Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature ^[26] A desert is a landscape form or region that receives very little precipitation. Landscape comprises the visible features of an area of land including physical elements such as Landforms living elements of flora and fauna abstract elements such as lighting In Meteorology, precipitation (also known as one class of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric Deserts usually have a large diurnal and seasonal temperature range, with high daytime temperatures (in summer up to 45 °C or 113 °F), and low night-time temperatures (in winter down to 0 °C; 32 °F) due to extremely low humidity. Diurnal temperature variation is a Meteorological term that relates to the variation in Temperature that occurs from the highs of the Day to the cool of Humidity is the amount of water vapor in the air In daily language the term "humidity" is normally taken to mean Relative humidity. Many deserts are formed by rain shadows, as mountains block the path of moisture and precipitation to the desert. For the Australian television series see Rain Shadow (TV series. ^[27]

Thornthwaite

See also: Microthermal, Mesothermal, and Megathermal

This climate classification method monitors the soil water budget using the concept of evapotranspiration. In Climatology, the term microthermal is used to denote the Continental climates of Eurasia and North America. In Climatology, the term mesothermal is used to refer to certain forms of Climate found typically in the Earth 's Temperate Zones. In Climatology, the term megathermal (or less commonly macrothermal) is sometimes used as a synonym for " Tropical. ^[9] It monitors the portion of total precipitation used to nourish vegetation over a certain area. ^[28] It uses indices such as a humidity index and an aridity index to determine an area's moisture regime based upon its average temperature, average rainfall, and average vegetation type. ^[29] The lower the value of the index is any given area, the drier the area is.

The moisture classification includes climatic classes with descriptors such as hyperhumid, humid, subhumid, subarid, semi-arid (values of -20 to -40), and arid (values below -40). ^[30] Humid regions experience more precipitation than evaporation each year, while arid regions experience greater evaporation than precipitation on an annual basis. A total of 33 percent of the earth's landmass is considered either arid of semi-arid, including southwest North America, southwest South America, most of northern and a small part of southern Africa, southwest and portions of eastern Asia, as well as much of Australia. ^[31] Studies suggest that precipitation effectiveness (PE) within the Thornthwaite moisture index is overestimated in the summer and underestimated in the winter. ^[32] This index can be effectively used to determine the number of herbivore and mammal species numbers within a given area. Herbivory is a form of Predation in which an Organism, known as a herbivore, consumes principally Autotrophs ref name=Campbell>Campbell Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands ^[33] The index is also used in studies of climate change. ^[32]

Thermal classifications within the Thornthwaite scheme include microthermal, mesothermal, and megathermal regimes. A mircothermal climate is one of low annual mean temperatures, generally between 0 °C (32 °F) and 14 °C (57 °F) which experiences short summers and has a potential evaporation between 14 centimetres (5. 5 in) and 43 centimetres (17 in). ^[34] A mesothermal climate lacks persistent heat or persistent cold, with potential evaporation between 57 centimetres (22 in) and 114 centimetres (45 in). ^[35] A megathermal climate is one with persistent high temperatures and abundant rainfall, with potential evaporation in excess of 114 centimetres (45 in). ^[36]

Record

Modern

Instrumental temperature record of the last 150 years

Details of the modern climate record are known through the taking of measurements from such weather instruments as thermometers, barometers, and anemometers during the past few centuries. The thermometer is a device that measures Temperature or Temperature gradient using a variety of different principles it comes from the Greek roots History The first barometer is thought to have been built unintentionally by Gasparo Berti, sometime between 1640 and 1643 An anemometer is a device for measuring wind speed and is one instrument used in a Weather station. The instruments used to study weather conditions over the modern time scale, their known error, their immediate environment, and their exposure have changed over the years, which must be considered when studying the climate of centuries past. ^[37]

Paleoclimatology

Main article: Paleoclimatology

Paleoclimatology is the study of past climate over a great period of the Earth's history. Paleoclimatology (also Palaeoclimatology) is the study of Climate change taken on the scale of the entire History of Earth. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 It uses evidence from ice sheets, tree rings, sediments, coral, and rocks to determine the past state of the climate. It demonstrates periods of stability and periods of change and can indicate whether changes follow patterns such as regular cycles. ^[38]

Climate change

Variations in CO₂, temperature and dust from the Vostok ice core over the past 450,000 years

See also: Climate change, Global warming, temperature record, and attribution of recent climate change

Climate change refers to the variation in the Earth's global climate or in regional climates over time. Vostok Station (Станция Восток is a Russian (formerly Soviet) Research station located near the Southern Pole of Inaccessibility Climate change is any long-term significant change in the “average weather” that a given region experiences Global warming is the increase in the average measured temperature of the For extreme records instead of records as a set of data see Temperature extremes The temperature record shows the fluctuations of the See also Global warming, Climate change, Climate change denial Attribution of recent climate change is the effort to scientifically ascertain EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 It describes changes in the variability or average state of the atmosphere over time scales ranging from decades to millions of years. These changes can be caused by processes internal to the Earth, external forces (e. g. variations in sunlight intensity) or, more recently, human activities. ^[39]

In recent usage, especially in the context of environmental policy, the term "climate change" often refers only to changes in modern climate, including the rise in average surface temperature known as global warming. Environmental policy is any (course of action deliberately taken (or not taken to manage human activities with a view to prevent reduce or mitigate harmful effects on nature and natural Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Global warming is the increase in the average measured temperature of the In some cases, the term is also used with a presumption of human causation, as in the United Nations Framework Convention on Climate Change (UNFCCC). The United Nations ( UN) is an International organization whose stated aims are to facilitate cooperation in International law, International security Annex I and Annex II Countries and Developing Countries Signatories to the UNFCCC are split into three groups Annex I countries (industrialized countries The UNFCCC uses "climate variability" for non-human caused variations. ^[40]

Earth has undergone periodic climate shifts in the past, including four major ice ages. An ice age is a period of long-term reduction in the Temperature of the Earth 's surface and atmosphere resulting in an expansion of continental Ice sheets These consisting of glacial periods where conditions are colder than normal, separated by interglacial periods. An interglacial is a geological interval of warmer global average temperature that separates Glacial periods within an Ice age. The accumulation of snow and ice during a glacial period increases the surface albedo, reflecting more of the Sun's energy into space and maintaining a lower atmospheric temperature. The albedo of an object is the extent to which it diffusely reflects light from the sun Increases in greenhouse gases, such as by volcanic activity, can increase the global temperature and produce an interglacial. Greenhouse gases are gaseous constituents of the atmosphere bothnatural and anthropogenic that absorb and emit radiation at specific wavelengths within the spectrum of thermal infrared Suggested causes of ice age periods include the positions of the continents, variations in the Earth's orbit, changes in the solar output, and vulcanism. A continent is one of several large Landmasses on Earth. They are generally identified by Convention rather than any strict criteria with seven regions ^[41]

Climate models

See also: Climate models and Climatology

Climate models use quantitative methods to simulate the interactions of the atmosphere,^[42] oceans, land surface and ice. This article is about the theories and mathematics of climate modeling Climatology (from Greek grc κλίμα klima, "region zone" and grc -λογία -logia) is the study of Climate, scientifically Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five An ocean (from Greek, ''Okeanos'' (Oceanus) is a major body of saline water, and a principal component of the Hydrosphere. They are used for a variety of purposes from study of the dynamics of the weather and climate system to projections of future climate. All climate models balance, or very nearly balance, incoming energy as short wave (including visible) electromagnetic radiation to the earth with outgoing energy as long wave (infrared) electromagnetic radiation from the earth. Any imbalance results in a change in the average temperature of the earth.

The most talked-about models of recent years have been those relating temperature to the build-up of greenhouse gases in the atmosphere, primarily carbon dioxide (see greenhouse gas). Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Greenhouse gases are gaseous constituents of the atmosphere bothnatural and anthropogenic that absorb and emit radiation at specific wavelengths within the spectrum of thermal infrared These models predict an upward trend in the global mean surface temperature, with the most rapid increase in temperature being projected for the higher latitudes of the Northern Hemisphere. See also Temperature record. The instrumental temperature record shows the fluctuations of the Temperature of the atmosphere and the oceans as

Models can range from relatively simple to quite complex:

• A simple radiant heat transfer model that treats the earth as a single point and averages outgoing energy
• this can be expanded vertically (radiative-convective models), or horizontally
• finally, (coupled) atmosphere–ocean–sea ice global climate models discretise and solve the full equations for mass and energy transfer and radiant exchange. Sea ice is formed from Ocean water that freezes Because the Oceans consist of Saltwater, this occurs at about -1 This article is about computer-driven prediction of Earth's climate for the theories and mathematics of climate modeling please see Climate model. ^[43]

See also

• Climate change
• Biome - an ecological term for a major regional group of distinctive plant and animal communities best adapted to the region's physical environment
• Climatology
• Effect of sun angle on climate
• Electronic Climate Control
• Microclimate
• Solar variation
• Temperature extreme
• National Climatic Data Center
• Climate Prediction Center

References

External links

• IFAS AgClimate
• Climate Models and modeling groups
• Climate Prediction Project
• WorldClimate
• ESPERE Climate Encyclopaedia
• Global Climate Data
• Climate index and mode information
• A current view of the Bering Sea Ecosystem and Climate
• Climate: Data and charts for world and US locations
• World climates list and articles