Oceanic climate facts for kids

Seattle, a city with an oceanic climate

An oceanic climate, also known as a maritime climate, has cool or mild winters and does not have dry or hot summers. Most places with this type of climate have weather that changes frequently. Most of it is classified as Cfb in the Köppen climate classification with each season having moderate or high rainfall, and warm summers. Cities with this climate include: Dublin, London, Bergen, Bilbao, Paris, Brussels, Amsterdam, Hamburg, Melbourne and Auckland.

There is a subarctic version of it with shorter summers (Cfc), which includes the Faroe Islands. The subtropical highland climate (Cwb and Cwc) is sometimes considered a subtype of the oceanic climate.

Precipitation

Locations with oceanic climates tend to feature frequent cloudy conditions with precipitation, low hanging clouds, and frequent fronts and storms. Thunderstorms are normally few. In most areas with an oceanic climate, precipitation comes in the form of rain for the majority of the year. Most oceanic climate zones, or at least a part of them, however, experience at least one snowfall per year. Snowfall is more frequent and commonplace in the subpolar oceanic climates due to the colder weather in those locations.

Temperature

Overall temperature characteristics of the oceanic climates feature cool temperatures and infrequent extremes of temperature. In the Köppen climate classification, oceanic climates have a mean temperature of 0 °C (32 °F) or higher (or −3 °C (27 °F) or higher) in the coldest month, compared to continental climates where the coldest month has a mean temperature of below 0 °C (32 °F) (or −3 °C (27 °F)). Summers are warm but not hot, with the warmest month having a mean temperature below 22 °C (72 °F). Poleward of the latter is a subtype of it and is the subpolar oceanic climate (Köppen Cfc), with long but relatively mild (for their latitude) winters and cool and short summers (average temperatures of at least 10 °C (50 °F) for one to three months).

Varieties

Marine west coast (Cfb)

Temperate oceanic climates, also known as "marine mild winter" climates or simply oceanic climates, are found either at middle latitudes. They are often found on or near the west coast of continents; hence another name for Cfb, "marine west coast climates". In addition to moderate temperatures year-round, one of the characteristics is the absence of a dry season. Except for western Europe, this type of climate is confined to narrow bands of territory, largely in mid or high latitudes, although it can appear in elevated areas of continental terrain in low latitudes, e.g. plateaus in the subtropics. It exists in both hemispheres between 35° and 60°: at low altitudes between Mediterranean, humid continental, and subarctic climates.

Western sea breezes ease temperatures and moderates the winter, especially if warm sea currents are present, and cause cloudy weather to predominate. Precipitation is constant, especially in colder months, when temperatures are warmer than elsewhere at comparable latitudes. This climate can occur farther inland if no mountain ranges are present or nearby. As this climate causes sufficient moisture year-round without permitting deep snow cover, vegetation typically prospers in this climate. Deciduous trees are predominant in this climate region. However, conifers such as spruce, pine, and cedar are also common in few areas, and fruits such as apples, pears, and grapes can often be cultivated here.

In the hottest month, the average temperature is below 22 °C (72 °F), and at least four months feature average temperatures higher than 10 °C (50 °F). The average temperature of the coldest month must not be colder than −3–0 °C (27–32 °F), or the climate will be classified as continental. The average temperature variations in the year are between 10–15 °C (50–59 °F), with average annual temperatures between 6–13 °C (43–55 °F). Rain values can vary from 50–500 cm (20–197 in), depending on whether mountains cause orographic precipitation. Frontal cyclones can be common in marine west coast regions, with some areas experiencing more than 150 rainy days annually, but strong storms are rare.

Zennor, United Kingdom

Cfb climates are predominant in most of Europe except the northeast, as global temperatures became warmer towards late 20th and early 21st century. However, just a few decades ago, oceanic climate was only present in parts of Western Europe, including northern Spain, northwestern Portugal (mountains), Belgium, Britain, France, Ireland, and the Netherlands. They are the main climate type in New Zealand and the Australian states of Tasmania, Victoria, and southeastern New South Wales (starting from the Illawarra region). In North America, they are found mainly in Washington, Oregon, Vancouver Island, and neighbouring parts of British Columbia, as well as many coastal areas of southeast Alaska. There are pockets of Cfb in most South American countries, mostly in regions of southern Chile and Argentina, parts of the provinces of Chubut, Santa Cruz, and southeast Buenos Aires province in Argentina, the highest elevations of the Brazilian Highlands, and due to variations in rainfall and temperature patterns in some places of the Tropical Andes in Bolivia, Perú, Ecuador, Colombia and Venezuela. In Western Asia, the climate can be found close to sea level on the Black Sea coast of northern Turkey and Georgia, often transitional to humid subtropical. While Cfb zones are rare in Africa, one dominates the coastline of the Eastern Cape in South Africa.

The climate subtype can also be found in Nantucket, Massachusetts (in the immediate west and northwest in transition for humid continental, the remainder of Cape Cod)

Subtropical highland variety (Cfb, Cwb)

Nuwara Eliya, Sri Lanka

The subtropical highland climate is a climate variety often grouped together with oceanic climates which exists in some mountainous or elevated portions of the world in either the subtropics or tropics. Despite the latitude, the higher elevations of these regions mean that the climate shares characteristics with oceanic climates.

Subtropical highland climates with uniform rainfall (Cfb) usually have rainfall spread relatively evenly throughout the year, similar to other oceanic climates but unlike these climates, they have a high diurnal temperature variation and low humidity, owing to their inland location and relatively high elevation. Subtropical highland climates with monsoon influence (Cwb), have distinctive wet summers and dry winters.

In locations outside the tropics, other than the drying trend in the winter, subtropical highland climates tend to be essentially identical to an oceanic climate, with mild summers and noticeably cooler winters, plus, in some instances, some snowfall. In the tropics, a subtropical highland climate typically features spring-like weather year-round. Temperatures there remain relatively constant throughout the year and snowfall is seldom seen due to warmer winters than most oceanic climates.

Areas with this climate feature monthly averages below 22 °C (72 °F) but above −3 °C (27 °F) (or 0 °C (32 °F) using American standards). At least one month's average temperature is below 18 °C (64 °F). Without their elevation, many of these regions would likely feature either humid subtropical or tropical climates.

This type of climate exists in parts of east, south and southeastern Africa, interior southern Africa and elevated portions of eastern Africa as far north as Ethiopia and of western Africa (west region of Cameroon) up to the southwestern Angola highlands also share this climate type. The exposed areas of High Atlas, some mountainous areas across southern Europe, mountainous sections of North America, including parts of the southern Appalachians and the Central America Volcanic Arc. In South America, it can be found mainly in temperate mountainous areas in the Tropical Andes, Venezuelan Coastal Range, the highest elevations of Serra do Mar in Southeastern Brazil, and tepuis of the Guiana Shield. Most of Yunnan and mountainous areas across Southeast Asia, parts of the Himalayas, parts of Sri Lanka, and parts of the Hawaiian Islands of Maui and Hawaii. In the Caribbean, only the peaks in the highest mountain ranges have this climate (including the Blue Mountains in Jamaica and Cerro Maravilla in Puerto Rico), with only Hispaniola's Cordillera Central and Chaîne de la Selle having significant urban settlements under this climate zone, such as cities like Kenscoff in Haiti and Constanza in the Dominican Republic.

Subpolar oceanic and cold subtropical highland varieties (Cfc, Cwc)

Areas with subpolar oceanic climates feature an oceanic climate but are usually located closer to polar regions, with long but relatively mild winters and short, cool summers. As a result of their location, these regions tend to be on the cool end of oceanic climates, approaching to polar regions. 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. Subpolar oceanic climates feature only one to three months of average monthly temperatures that are at least 10 °C (50 °F). As with oceanic climates, none of its average monthly temperatures fall below -3.0 °C (26.6 °F) or 0 °C depending on the isotherm used. Typically, these areas in the warmest month experience daytime maximum temperatures below 17 °C (63 °F), while the coldest month features highs near or slightly above freezing and lows just below freezing while keeping the average warm enough. It typically carries a Cfc designation, though very small areas in Argentina and Chile have summers sufficiently short to be Cwc with fewer than four months over 10 °C (50 °F).

This variant of an oceanic climate is found in parts of coastal Iceland, the Faroe Islands, upland/mountainous parts of Scotland and Northern England, northwestern coastal areas of Norway (most of Lofoten, Vesterålen, warmest part of Tromsø reaching to 71°N on some islands), uplands/highlands in western Norway, the Aleutian Islands of Alaska and northern parts of the Alaskan Panhandle, the southwest of Argentina and Chile, and a few highland areas of Tasmania, and the Australian and Southern Alps. This type of climate is even found in very remote parts of the New Guinea Highlands. 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.

Small areas in Yunnan, Sichuan and parts of Bolivia and Peru have summers sufficiently short to be Cwc with fewer than four months over 10 °C (50 °F). However, due to the high altitudes at these locations, these areas feature Cwc climates. This is the cold variant of the monsoon-influenced subtropical highland climate. El Alto, Bolivia, is one of the few confirmed towns that features this variation of the subtropical highland climate.

Examples

Oceania

• Ashburton, New Zealand (Cfb)
• Auckland, New Zealand (Cfb)
• Christchurch, New Zealand (Cfb)
• Hobart, Tasmania, Australia (Cfb)
• Lithgow, New South Wales, Australia (Cfb)
• Melbourne, Victoria, Australia (Cfb)
• Volcano, Hawaii, United States (Cfb)
• Wabag, Papua New Guinea (Cfb)
• Wellington, New Zealand (Cfb)
• Wollongong, New South Wales, Australia (Cfb, bordering on Cfa)

South America

• Bogotá, Colombia (Cfb)
• Caxias do Sul, Rio Grande do Sul, Brazil (Cfb)
• Chachapoyas, Peru (Cfb)
• Cuenca, Ecuador (Cfb)
• Curitiba, Paraná, Brazil (Cfb)
• La Paz, Bolivia (Cwb, bordering on Cwc)
• Manizales, Colombia (Cfb)
• Mar del Plata, Argentina (Cfb)
• Mucuchíes, Venezuela (Cfb)
• Osorno, Los Lagos Region, Chile (Cfb)
• Puerto Montt, Los Lagos Region, Chile (Cfb)
• Punta del Este, Uruguay (Cfb, bordering on Cfa)
• Quito, Ecuador (Cfb)
• Sucre, Bolivia (Cwb)
• Teresópolis, Rio de Janeiro state, Brazil (Cfb)
• Valdivia, Los Ríos Region, Chile (Cfb)

Southern Indian Ocean

• Île Amsterdam, French Southern and Antarctic Lands (Cfb)
• Île Saint-Paul, French Southern and Antarctic Lands (Cfb)

Images for kids

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  São Joaquim, Brazil

See also

In Spanish: Clima oceánico para niños