Geography of Spain
Spain is a country located in southwestern Europe occupying most of the Iberian Peninsula and includes a small exclave inside France called Llívia as well as the Balearic Islands in the Mediterranean, the Canary Islands in the Atlantic Ocean 108 km off northwest Africa, five places of sovereignty on and off the coast of North Africa: Ceuta, Islas Chafarinas, Peñón de Alhucemas, Peñón de Vélez de la Gomera. The Spanish mainland is bordered to the south and east entirely by the Mediterranean Sea. With an area of 504,030 km2, Spain is the largest country in Southern Europe, the second largest country in Western Europe and the fourth largest country in the European continent, it has an average altitude of 650 m. Its total area is 504,782 km2 of which 499,542 km2 is land and 5,240 km2 is water. Spain lies between latitudes 36° and 44° N, longitudes 19° W and 5° E, its Atlantic coast is 710 km long. The Pyrenees mountain range, extends 435 km from the Mediterranean to the Bay of Biscay. In the extreme south of Spain lie the Straits of Gibraltar, which separate the Iberian peninsula and the rest of Europe from Ceuta and Morocco in North Africa.
Spain shares land boundaries with France and Andorra along the Pyrenees in the northeast, with Portugal on the west, with the small British Overseas Territory of Gibraltar near the southernmost tip. The affiliation of Gibraltar has continued to be a contentious issue between Britain; the sovereignty of the plazas de soberanía on the Mediterranean coast of Morocco is disputed by Morocco. Spain has a small exclave inside France called Llívia; the majority of Spain's peninsular region consists of the Meseta Central, a highland plateau rimmed and dissected by mountain ranges. Other landforms include narrow coastal plains and some lowland river valleys, the most prominent of, the Andalusian Plain in the southwest; the country can be divided into ten natural regions or subregions: the dominant Meseta Central, the Cantabrian Mountains and the northwest region, the Ibérico region, the Pyrenees, the Penibético region in the southeast, the Andalusian Plain, the Ebro Basin, the coastal plains, the Balearic Islands, the Canary Islands.
These are grouped into four types: the Meseta Central and associated mountains, other mountainous regions, lowland regions, islands. The Meseta Central is a vast plateau in the heart of peninsular Spain, which has elevations that range from 610 to 760 m. Rimmed by mountains, the Meseta Central slopes to the west and to the series of rivers that form some of the border with Portugal; the Sistema Central, described as the "dorsal spine" of the Meseta Central, divides the Meseta into northern and southern subregions, the former higher in elevation and smaller in area than the latter. The Sistema Central rims the capital city of Madrid with peaks that rise to over 2,400 m within the Madrid region. South-west of Madrid, the Sistema Central shows Pico Almanzor, of 2,592 m; the mountains of the Sistema Central, which continue westward into Portugal, display some glacial features. Despite their height, the mountain system does not create a major barrier between the northern and the southern portions of the Meseta Central because several passes permit road and railroad transportation to the northwest and the northeast.
The southern portion of the Meseta is further divided by twin mountain ranges, the Montes de Toledo running to the east with the Sierra de Guadalupe, to the west. Their peaks do not rise much higher than 1,500 m. With many easy passes, including those that connect the Meseta with the Andalusian Plain, the Montes de Toledo do not present an obstacle to transportation and communication; this chain of lower mountain ranges is separated from the Sistema Central to the north by the longest river in the Iberian Peninsula: the Tagus River. The mountain regions that rim the Meseta Central and are associated with it are the Sierra Morena, the Cordillera Cantábrica, the Sistema Ibérico. Forming the southern edge of the Meseta Central, the Sierra Morena merges in the east with the southern extension of the Sistema Iberico and reaches westward along the northern edge of the Rio Guadalquivir valley to join the mountains in southern Portugal; the massif of the Sierra Morena extends northward to the Río Guadiana, which separates it from the Sistema Central.
Despite their low elevations surpassing 1,300 m, the mountains of the Sierra Morena are rugged at their southern edge. The Cordillera Cantábrica, a limestone formation, runs parallel to, close to, the northern coast near the Bay of Biscay, its highest points are the Picos de Europa, surpassing 2,600 m. The Cordillera Cantábrica abruptly drops 1,500 m some 30 km from the coast. To the west lie the hills of the northwest region and to the east the Basque mountains that link them to the Pyrenees; the Sistema Ibérico extends from the Cordillera Cantábrica southeastward and, close to the Mediterranean, spreads out from the Río Ebro to the Río Júcar. The barren, rugged slopes of this mountain range cover an area of close to 21,000 square kilometers; the mountains exce
Provinces of Spain
Spain and its autonomous communities are divided into fifty provinces. Spain's provincial system was recognized in its 1978 constitution but its origin dates back to 1833. Ceuta and the Plazas de soberanía are not part of any provinces; the layout of Spain's provinces follows the pattern of the territorial division of the country carried out in 1833. The only major change of provincial borders since that time has been the subdivision of the Canary Islands into two provinces rather than one; the provinces served as transmission belts for policies enacted in Madrid, as Spain was a centralised state for most of its modern history. The importance of the provinces has declined since the adoption of the system of autonomous communities in the period of the Spanish transition to democracy, they remain electoral districts for national elections and as geographical references: for instance in postal addresses and telephone codes. A small town would be identified as being in, Valladolid province rather than the autonomous community of Castile and León.
The provinces were the "building-blocks". No province is divided between more than one of these communities. Most of the provinces—with the exception of Álava, Biscay, Guipúzcoa, Balearic Islands, La Rioja, Navarra — are named after their principal town. Only two capitals of autonomous communities — Mérida in Extremadura and Santiago de Compostela in Galicia — are not the capitals of provinces. Seven of the autonomous communities comprise no more than one province each: Asturias, Balearic Islands, Cantabria, La Rioja, Madrid and Navarra; these are sometimes referred to as "uniprovincial" communities. The table below lists the provinces of Spain. For each, the capital city is given, together with an indication of the autonomous community to which it belongs and a link to a list of municipalities in the province; the names of the provinces and their capitals are ordered alphabetically according to the form in which they appear in the main Wikipedia articles describing them. Unless otherwise indicated, their Spanish language names are the same.
List of Spanish provinces by population List of Spanish provinces by area Spanish Federation of Municipalities and Provinces Autonomous communities of Spain Comarcas of Spain ISO 3166-2:ESGeneral: Political divisions of Spain Maps of the provinces of Spain Maps of Spain's Provinces List of municipalities of Spain listed by province from the Spanish INE
The Ebro is a river on the Iberian Peninsula. It is the second longest river in the Iberian peninsula after the Tagus and the second biggest by discharge volume and by drainage area after the Douro; the Ebro flows through the following cities: Reinosa in Cantabria. The source of the river Ebro is from the Latin words Fontes Iberis, source of the Ebro. Close by is a large artificial lake, Embalse del Ebro, created by the damming of the river; the upper Ebro rushes through rocky gorges in Burgos Province. Flowing eastwards it begins forming a wider river valley of limestone rocks when it reaches Navarre and La Rioja thanks to many tributaries flowing down from the Iberian System on one side, the Navarre mountains and the western Pyrenees, on the other. There, the climate becomes progressively more continental, with more extreme temperatures and drier characteristics, therefore experiencing hot and dry summers which resemble summers seen in arid and semiarid climates. Karst geological processes shaped the landscape of layers of soluble carbonate rock of extensive limestone bedrock formed in an ancient seabed.
Aragonite, a mineral named for Aragon, attests to the fact that carbonates are abundant in the central Ebro Valley. The valley expands and the Ebro's flow becomes slower as its water volume increases, flowing across Aragon. There, larger tributaries flowing from the central Pyrenees and the Iberian System discharge large amounts of water in spring during the thawing season of the mountain snow; as it flows through Zaragoza the Ebro, is a sizeable river. There, the Basilica of Our Lady of the Pillar stands next to the Ebro; the soils in most of the valley are poor soils: calcareous, pebbly and sometimes salted with saltwater endorheic lagoons. The semi-arid interior of the Ebro Valley has either drought summers and a semi-desert climate with rainfall between 400 and 600 mm, with a maximum in the fall and spring, it is covered with chaparral vegetation. Summers are hot and winters are cold; the dry summer season has temperatures of more than 35 °C reaching over 40 °C. In winter, the temperatures drop below 0 °C.
In some areas the vegetation depends on moisture produced by condensation fog. It is a continental Mediterranean climate with extreme temperatures. There are many ground frosts on clear nights, sporadic snowfalls; the biomes are diverse in these Mediterranean climate zones: Mediterranean forests and scrub. Hinterlands are distinctive on account of extensive sclerophyll shrublands known as maquis, or garrigues; the dominant species are Quercus ilex. These trees form monospecific communities or communities integrated with Pinus, Mediterranean buckthorns, Chamaerops humilis, Pistacia, Thymus, so on; the hinterland climate becomes progressively more continental and drier, therefore there is an end from extreme temperatures accompanied by slow-growing dwarf juniper species to unvegetated desert steppes as in "llanos de Belchite" or "Calanda desert". The mountain vegetation is coniferous forests that are drought adapted, trees in the genus Quercus with different drought tolerance in the wetter highlands.
Halophiles extremophile characteristic communities are frequent in endorheic areas such as lagoons and creeks, which are Tamarix covered and include endemic species of bryophytes, plumbaginacea, Carex, asteraceaes, etc. Their presence is related to the marine origin of the Ebro valley and the extensive marine deposits in the same area. After reaching Catalonia, the Ebro Valley narrows, the river becomes constrained by mountain ranges, making wide bends. Massive dams have been built in this area, such as the dams at Riba-roja and Flix. In the final section of its course the river bends flows through spectacular gorges; the massive calcareous cliffs of the Serra de Cardó range constrain the river during this last stretch, separating the Ebro Valley from the Mediterranean coastal area. After passing the gorges, the Ebro bends again eastwards near Tortosa before discharging in a delta on the Mediterranean Sea close to Amposta in the province of Tarragona; the Ebro Delta, in the Province of Tarragona, Catalonia, is at 340 km2 one of the largest wetland areas in the western Mediterranean region.
The delta has expanded on soils washed downriver—the historical rate of growth of the delta is demonstrated by the town of Amposta. A seaport in the 4th century, it is now well inland from the current rivermouth; the rounded form of the delta attests to the balance between sediment deposition by the Ebro and removal of this material by wave erosion. The modern delta is in intensive agricultural use for rice and vegetables; the Ebro delta has numerous beaches and salt pans that provide habitat for over 300 species of birds. In 1983 Spain designated a large part of the delta as the Ebro Delta Natural Park to protect its natural resources. A network of canals and irrigation ditches constructed by both agricultural and conservation groups are helping to maintain the ecologic and economic resources of the Ebro
Spain the Kingdom of Spain, is a country located in Europe. Its continental European territory is situated on the Iberian Peninsula, its territory includes two archipelagoes: the Canary Islands off the coast of Africa, the Balearic Islands in the Mediterranean Sea. The African enclaves of Ceuta, Peñón de Vélez de la Gomera make Spain the only European country to have a physical border with an African country. Several small islands in the Alboran Sea are part of Spanish territory; the country's mainland is bordered to the south and east by the Mediterranean Sea except for a small land boundary with Gibraltar. With an area of 505,990 km2, Spain is the largest country in Southern Europe, the second largest country in Western Europe and the European Union, the fourth largest country in the European continent. By population, Spain is the fifth in the European Union. Spain's capital and largest city is Madrid. Modern humans first arrived in the Iberian Peninsula around 35,000 years ago. Iberian cultures along with ancient Phoenician, Greek and Carthaginian settlements developed on the peninsula until it came under Roman rule around 200 BCE, after which the region was named Hispania, based on the earlier Phoenician name Spn or Spania.
At the end of the Western Roman Empire the Germanic tribal confederations migrated from Central Europe, invaded the Iberian peninsula and established independent realms in its western provinces, including the Suebi and Vandals. The Visigoths would forcibly integrate all remaining independent territories in the peninsula, including Byzantine provinces, into the Kingdom of Toledo, which more or less unified politically and all the former Roman provinces or successor kingdoms of what was documented as Hispania. In the early eighth century the Visigothic Kingdom fell to the Moors of the Umayyad Islamic Caliphate, who arrived to rule most of the peninsula in the year 726, leaving only a handful of small Christian realms in the north and lasting up to seven centuries in the Kingdom of Granada; this led to many wars during a long reconquering period across the Iberian Peninsula, which led to the creation of the Kingdom of Leon, Kingdom of Castile, Kingdom of Aragon and Kingdom of Navarre as the main Christian kingdoms to face the invasion.
Following the Moorish conquest, Europeans began a gradual process of retaking the region known as the Reconquista, which by the late 15th century culminated in the emergence of Spain as a unified country under the Catholic Monarchs. Until Aragon had been an independent kingdom, which had expanded toward the eastern Mediterranean, incorporating Sicily and Naples, had competed with Genoa and Venice. In the early modern period, Spain became the world's first global empire and the most powerful country in the world, leaving a large cultural and linguistic legacy that includes more than 570 million Hispanophones, making Spanish the world's second-most spoken native language, after Mandarin Chinese. During the Golden Age there were many advancements in the arts, with world-famous painters such as Diego Velázquez; the most famous Spanish literary work, Don Quixote, was published during the Golden Age. Spain hosts the world's third-largest number of UNESCO World Heritage Sites. Spain is a secular parliamentary democracy and a parliamentary monarchy, with King Felipe VI as head of state.
It is a major developed country and a high income country, with the world's fourteenth largest economy by nominal GDP and sixteenth largest by purchasing power parity. It is a member of the United Nations, the European Union, the Eurozone, the Council of Europe, the Organization of Ibero-American States, the Union for the Mediterranean, the North Atlantic Treaty Organization, the Organisation for Economic Co-operation and Development, Organization for Security and Co-operation in Europe, the Schengen Area, the World Trade Organization and many other international organisations. While not an official member, Spain has a "Permanent Invitation" to the G20 summits, participating in every summit, which makes Spain a de facto member of the group; the origins of the Roman name Hispania, from which the modern name España was derived, are uncertain due to inadequate evidence, although it is documented that the Phoenicians and Carthaginians referred to the region as Spania, therefore the most accepted etymology is a Semitic-Phoenician one.
Down the centuries there have been a number of accounts and hypotheses: The Renaissance scholar Antonio de Nebrija proposed that the word Hispania evolved from the Iberian word Hispalis, meaning "city of the western world". Jesús Luis Cunchillos argues that the root of the term span is the Phoenician word spy, meaning "to forge metals". Therefore, i-spn-ya would mean "the land where metals are forged", it may be a derivation of the Phoenician I-Shpania, meaning "island of rabbits", "land of rabbits" or "edge", a reference to Spain's location at the end of the Mediterranean. The word in question means "Hyrax" due to Phoenicians confusing the two animals. Hispania may derive from the poetic use of the term Hesperia, reflecting the Greek perception of Italy as a "western land" or "land of the setting sun" (Hesperia
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present. As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are uncertain; the name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich. The Oligocene is followed by the Miocene Epoch; the Oligocene is the final epoch of the Paleogene Period. The Oligocene is considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included a global expansion of grasslands, a regression of tropical broad leaf forests to the equatorial belt; the start of the Oligocene is marked by a notable extinction event called the Grande Coupure. By contrast, the Oligocene–Miocene boundary is not set at an identified worldwide event but rather at regional boundaries between the warmer late Oligocene and the cooler Miocene.
Oligocene faunal stages from youngest to oldest are: The Paleogene Period general temperature decline is interrupted by an Oligocene 7-million-year stepwise climate change. A deeper 8.2 °C, 400,000-year temperature depression leads the 2 °C, seven-million-year stepwise climate change 33.5 Ma. The stepwise climate change began 32.5 Ma and lasted through to 25.5 Ma, as depicted in the PaleoTemps chart. The Oligocene climate change was a global increase in ice volume and a 55 m decrease in sea level with a related temperature depression; the 7-million-year depression abruptly terminated within 1–2 million years of the La Garita Caldera eruption at 28–26 Ma. A deep 400,000-year glaciated Oligocene Miocene boundary event is recorded at McMurdo Sound and King George Island. During this epoch, the continents continued to drift toward their present positions. Antarctica became more isolated and developed an ice cap. Mountain building in western North America continued, the Alps started to rise in Europe as the African plate continued to push north into the Eurasian plate, isolating the remnants of the Tethys Sea.
A brief marine incursion marks the early Oligocene in Europe. Marine fossils from the Oligocene are rare in North America. There appears to have been a land bridge in the early Oligocene between North America and Europe, since the faunas of the two regions are similar. Sometime during the Oligocene, South America was detached from Antarctica and drifted north towards North America, it allowed the Antarctic Circumpolar Current to flow cooling the Antarctic continent. Angiosperms continued their expansion throughout the world as tropical and sub-tropical forests were replaced by temperate deciduous forests. Open plains and deserts became more common and grasses expanded from their water-bank habitat in the Eocene moving out into open tracts; however at the end of the period, grass was not quite common enough for modern savannas. In North America, subtropical species dominated with cashews and lychee trees present, temperate trees such as roses and pines were common; the legumes spread, while sedges and ferns continued their ascent.
More open landscapes allowed animals to grow to larger sizes than they had earlier in the Paleocene epoch 30 million years earlier. Marine faunas became modern, as did terrestrial vertebrate fauna on the northern continents; this was more as a result of older forms dying out than as a result of more modern forms evolving. Many groups, such as equids, rhinos and camelids, became more able to run during this time, adapting to the plains that were spreading as the Eocene rainforests receded; the first felid, originated in Asia during the late Oligocene and spread to Europe. South America was isolated from the other continents and evolved a quite distinct fauna during the Oligocene; the South American continent became home to strange animals such as pyrotheres and astrapotheres, as well as litopterns and notoungulates. Sebecosuchians, terror birds, carnivorous metatheres, like the borhyaenids remained the dominant predators. Brontotheres died out in the Earliest Oligocene, creodonts died out outside Africa and the Middle East at the end of the period.
Multituberculates, an ancient lineage of primitive mammals that originated back in the Jurassic became extinct in the Oligocene, aside from the gondwanatheres. The Oligocene was home to a wide variety of strange mammals. A good example of this would be the White River Fauna of central North America, which were a semiarid prairie home to many different types of endemic mammals, including entelodonts like Archaeotherium, running rhinoceratoids, three-toed equids, nimravids and early canids like Hesperocyon. Merycoidodonts, an endemic American group, were diverse during this time. In Asia during the Oligocene, a group of running rhinoceratoids gave rise to the indricotheres, like Paraceratherium, which were the largest land mammals to walk the Earth; the marine animals of Oligocene oceans resembled today's fauna, such as the bivalves. Calcareous cirratulids appeared in the Oligocene; the fossil record of marine mammals is a little spotty during this time, not as well known as the Eocene o
Bay of Biscay
The Bay of Biscay is a gulf of the northeast Atlantic Ocean located south of the Celtic Sea. It lies along the western coast of France from Point Penmarc'h to the Spanish border, the northern coast of Spain west to Cape Ortegal; the south area of the Bay of Biscay washes over the northern coast of Spain and is known as the Cantabrian Sea. The average depth is 1,744 metres and the greatest depth is 4,735 metres; the Bay of Biscay is named after Biscay on the northern Spanish coast standing for the western Basque districts. Its name in other languages is: Asturian: golfu de Biscaya Basque: Bizkaiko golkoa Breton: pleg-mor Gwaskogn French: golfe de Gascogne Galician: golfo de Biscaia Gascon and Occitan: golf de Gasconha Latin: Sinus Biscaiensis Spanish: Golfo de Vizcaya Parts of the continental shelf extend far into the bay, resulting in shallow waters in many areas and thus the rough seas for which the region is known. Large storms occur in the bay during the winter months; the Bay of Biscay is home to some of the Atlantic Ocean's fiercest weather.
Up until recent years it was a regular occurrence for merchant vessels to founder in Biscay storms. The International Hydrographic Organization defines the limits of the Bay of Biscay as "a line joining Cap Ortegal to Penmarch Point"; the southernmost portion is the Cantabrian Sea. The main rivers that empty into the Bay of Biscay are Loire, Garonne, Adour, Bidasoa, Urumea, Urola, Artibai, Oka, Nervión, Agüera, Asón, Pas, Nansa, Sella, Nalón, Esva, Eo, Landro and Sor. In late spring and early summer a large fog triangle fills the southwestern half of the bay, covering just a few kilometers inland; as winter begins, weather becomes severe. Depressions enter from the west frequently and they either bounce north to the British Isles or they enter the Ebro Valley, dry out, are reborn in the form of powerful thunderstorms as they reach the Mediterranean Sea; these depressions cause severe weather at sea and bring light though constant rain to its shores. Sometimes powerful windstorms form if the pressure falls traveling along the Gulf Stream at great speed, resembling a hurricane, crashing in this bay with their maximum power, such as the Klaus storm.
The Gulf Stream enters the bay following the continental shelf's border anti-clockwise, keeping temperatures moderate all year long. The main cities on the shores of the Bay of Biscay are Bordeaux, Biarritz, Nantes, La Rochelle, Donostia-San Sebastián, Santander, Gijón and Avilés; the southern end of the gulf is called in Spanish "Mar Cantábrico", from the Estaca de Bares, as far as the mouth of Adour river, but this name is not used in English. It was named by Romans in the 1st century BC as Sinus Cantabrorum and Mare Gallaecum. On some medieval maps, the Bay of Biscay is marked as El Mar del los Vascos; the Bay of Biscay has been the site of many famous naval engagements over the centuries. In 1592 the Spanish defeated an English fleet during the eponymous Battle of the Bay of Biscay; the Biscay campaign of June 1795 consisted of a series of manoeuvres and two battles fought between the British Channel Fleet and the French Atlantic Fleet off the southern coast of Brittany during the second year of the French Revolutionary Wars.
USS Californian sank here after striking a naval mine on 22 June 1918. In 1920 SS Afrique sank after losing power and drifting into a reef in a storm with the loss of 575 lives. On 28 December 1943, the Battle of the Bay of Biscay was fought between HMS Glasgow and HMS Enterprise and a group of German destroyers as part of Operation Stonewall during World War II. U-667 sank on 25 August 1944 in position 46 ° 00 ′ N 01 ° 30 ′ W. All hands were lost. On 12 April 1970, Soviet submarine K-8 sank in the Bay of Biscay due to a fire that crippled the submarine's nuclear reactors. An attempt to save the sub failed, resulting in the death of forty sailors and the loss of four nuclear torpedoes. Due to the great depth, no salvage operation was attempted; the car ferries from Gijón to Nantes/Saint-Nazaire, Portsmouth to Bilbao and from Plymouth and Poole to Santander provide one of the most convenient ways to see cetaceans in European waters. Specialist groups take the ferries to hear more information. Volunteers and employees of ORCA observe and monitor cetacean activity from the bridge of the ships on Brittany Ferries' Portsmouth to Santander route.
Many species of whales and dolphins can be seen in this area. Most it is one of the few places in the world where the beaked whales, such as the Cuvier's beaked whale, have been observed frequently. Biscay Dolphin Research monitored cetacean activity from the P&O Ferries cruiseferry Pride of Bilbao, on voyages from Portsmouth to Bilbao. North Atlantic Right Whales, one of the most endangered whales, once came to the bay for feeding and for calving as well, but whaling activities by Basque people wiped them out sometime prior to 1850s; the eastern population of this species are considered to be extinct, a
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 located on the western coasts of continents, between 30 and 45 degrees north and south of the equator between oceanic climates towards the poles, semi-arid and arid climates towards the equator. In essence, due to the seasonal shift of the subtropical high-pressure belts with the apparent movement of the Sun, a Mediterranean climate is an intermediate type between these other climates, with winters warmer and drier than oceanic climates and summers imitating sunny weather in semi-arid and arid climates; the resulting vegetation of Mediterranean climates are the garrigue or maquis in the Mediterranean Basin, the chaparral in California, the fynbos in South Africa, the mallee in Australia, the matorral in Chile. Areas with this climate are where the so-called "Mediterranean trinity" of agricultural products have traditionally developed: wheat and olive.
Most large, historic cities of the Mediterranean basin lie within Mediterranean climatic zones, including Algiers, Beirut, İzmir, Marseille, Rome and Valencia. Examples of major cities with Mediterranean climates that lie outside of the historic Mediterranean basin include major examples as Adelaide, Cape Town, Dushanbe, Los Angeles, Perth, San Francisco and Victoria. Under the Köppen climate classification, "hot dry-summer" climates and "cool dry-summer" climates are referred to as "Mediterranean". Under the Köppen climate system, the first letter indicates the climate group. Temperate climates or "C" zones have an average temperature above 0 °C, but below 18 °C, in their coolest months; the second letter indicates the precipitation pattern. Köppen has defined a dry summer month as a month with less than 30 mm of precipitation and with less than one-third that of the wettest winter month. Some, use a 40 mm level; the third letter indicates the degree of summer heat: "a" represents an average temperature in the warmest month above 22 °C, while "b" indicates the average temperature in the warmest month below 22 °C.
Under the Köppen classification, dry-summer climates occur on the western sides of continents. Csb zones in the Köppen system include areas not associated with Mediterranean climates but with Oceanic climates, such as much of the Pacific Northwest, much of southern Chile, parts of west-central Argentina, parts of New Zealand. Additional highland areas in the subtropics meet Cs requirements, though they, are not associated with Mediterranean climates, as do a number of oceanic islands such as Madeira, the Juan Fernández Islands, the western part of the Canary Islands, the eastern part of the Azores. Under Trewartha's modified Köppen climate classification, the two major requirements for a Cs climate are revised. Under Trewartha's system, at least eight months must have average temperatures of 10 °C or higher, the average annual precipitation must not exceed 900 mm. Thus, under this system, many Csb zones in the Köppen system become Do, the rare Csc zones become Eo, with only the classic dry-summer to warm winter, low annual rainfall locations included in the Mediterranean type climate.
During summer, regions of Mediterranean climate are influenced by cold ocean currents which keep the weather in the region dry and pleasant. Similar to desert climates, in many Mediterranean climates there is a strong diurnal character to daily temperatures in the warm summer months due to strong heating during the day from sunlight and rapid cooling at night. In winter, Mediterranean climate zones are no longer influenced by the cold ocean currents and therefore warmer water settles near land and causes clouds to form and rainfall becomes much more likely; as a result, areas with this climate receive all of their precipitation during their winter and spring seasons, may go anywhere from 3 to 6 months during the summer without having any significant precipitation. In the lower latitudes, precipitation decreases in both the winter and summer because they are closer to the Horse latitudes, thus bringing smaller amounts of rain. Toward the polar latitudes, total moisture increases; the rainfall tends to be more evenly distributed throughout the year in Southern Europe, while in the Eastern Mediterranean and in Southern California the summer is nearly or dry.
In places where evapotranspiration is higher, steppe climates tend to prevail, but still follow the weather pattern of the Mediterranean climate. The majority of the regions with Mediterranean climates have mild winters and warm summers; however winter and summer temperatures can vary between different regions with a Mediterranean climate. For instance, in the case of winters and Los Angeles experience mild temperatures in the winter, with frost and snowfall unknown, whereas Tashkent has colder winters with annual frosts and snowfall. Or to consider summer, Athens experiences rather high temperatures in that season. In contrast, San Francisco has cool summers with daily highs around 21 °C due to