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58-443: The period of oscillation is roughly 15–30 years. Positive phases of the IPO are characterized by a warmer than average tropical Pacific and cooler than average northern Pacific. Negative phases are characterized by an inversion of this pattern, with cool tropics and warm northern regions. The IPO had positive phases (southeastern tropical Pacific warm) from 1922 to 1946 and 1978 to 1998, and

116-562: A consequence, the resulting Gulf Stream is a strong ocean current. It transports water at a rate of 30 million cubic metres per second (30 sverdrups ) through the Florida Straits. As it passes south of Newfoundland, this rate increases to 150 sverdrups. The volume of the Gulf Stream dwarfs all rivers that empty into the Atlantic combined, which total 0.6 sverdrups. It is weaker, however, than

174-590: A dry-climate area unsuitable at that time for the growth of bamboo. The invention of thermometers and barometers during the Scientific Revolution allowed for systematic recordkeeping, that began as early as 1640–1642 in England. Early climate researchers include Edmund Halley , who published a map of the trade winds in 1686 after a voyage to the southern hemisphere. Benjamin Franklin (1706–1790) first mapped

232-411: A few decades to as long as millions of years. The climate system receives nearly all of its energy from the sun. The climate system also gives off energy to outer space . The balance of incoming and outgoing energy, and the passage of the energy through the climate system, determines Earth's energy budget . When the incoming energy is greater than the outgoing energy, earth's energy budget is positive and

290-478: A generalized, overall description of the atmosphere or ocean which can be used to characterize the factors which effect the global climate system. El Niño–Southern Oscillation (ENSO) is a coupled ocean-atmosphere phenomenon in the Pacific Ocean responsible for much of the global variability of temperature, and has a cycle between two and seven years. The North Atlantic oscillation is a mode of variability that

348-413: A global network of thermometers , to prehistoric ice extracted from glaciers . As measuring technology changes over time, records of data often cannot be compared directly. As cities are generally warmer than the areas surrounding, urbanization has made it necessary to constantly correct data for this urban heat island effect. Climate models use quantitative methods to simulate the interactions of

406-451: A negative phase between 1947 and 1976. This climatology -related article is a stub . You can help Misplaced Pages by expanding it . This oceanography article is a stub . You can help Misplaced Pages by expanding it . Climatology Climatology (from Greek κλίμα , klima , "slope"; and -λογία , -logia ) or climate science is the scientific study of Earth's climate , typically defined as weather conditions averaged over

464-411: A period of at least 30 years. Climate concerns the atmospheric condition during an extended to indefinite period of time; weather is the condition of the atmosphere during a relative brief period of time. The main topics of research are the study of climate variability , mechanisms of climate changes and modern climate change . This topic of study is regarded as part of the atmospheric sciences and

522-437: A shallow frontal zone , forced by the Gulf Stream, during the cold season . Subtropical cyclones also tend to be generated near the Gulf Stream. About 75% of such systems documented between 1951 and 2000 formed near this warm-water current, with two annual peaks of activity occurring during May and October. Cyclones within the ocean itself form under the Gulf Stream, extending as deep as 3,500 m (11,500 ft) beneath

580-491: A subdivision of physical geography , which is one of the Earth sciences . Climatology includes some aspects of oceanography and biogeochemistry . The main methods employed by climatologists are the analysis of observations and modelling of the physical processes that determine climate. Short term weather forecasting can be interpreted in terms of knowledge of longer-term phenomena of climate, for instance climatic cycles such as

638-409: A year. Another major variable of climate is continentality: the distance to major water bodies such as oceans . Oceans act as a moderating factor, so that land close to it has typically less difference of temperature between winter and summer than areas further from it. The atmosphere interacts with other parts of the climate system , with winds generating ocean currents that transport heat around

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696-546: Is denser and colder (or more precisely, water that is still liquid at a lower temperature). In the North Atlantic Ocean, the water becomes so dense that it begins to sink down through less salty and less dense water. (The convective action is similar to a lava lamp .) This downdraft of cold, dense water becomes a part of the North Atlantic Deep Water , a southgoing stream. Very little seaweed lies within

754-418: Is equatorward. Because of the conservation of potential vorticity caused by the northward-moving winds on the subtropical ridge 's western periphery and the increased relative vorticity of northward-moving water, transport is balanced by a narrow, accelerating poleward current. This flows along the western boundary of the ocean basin, outweighing the effects of friction with the western boundary current, and

812-481: Is known as the Labrador Current . The conservation of potential vorticity also causes bends along the Gulf Stream, which occasionally break off as the Gulf Stream's position shifts, forming separate warm and cold eddies. This overall process, known as western intensification, causes currents on the western boundary of an ocean basin, such as the Gulf Stream, to be stronger than those on the eastern boundary. As

870-524: Is largely driven by thermohaline circulation . Its carrying warm water northeast across the Atlantic makes Western Europe and especially Northern Europe warmer and milder than it otherwise would be. A river of sea water, called the Atlantic North Equatorial Current , flows westwards off the coast of Central Africa. When this current interacts with the northeastern coast of South America, the current forks into two branches. One passes into

928-630: Is mainly contained to the lower atmosphere, the troposphere . The layer of atmosphere above, the stratosphere is also capable of creating its own variability, most importantly the Madden–Julian oscillation (MJO), which has a cycle of approximately 30 to 60 days. The Interdecadal Pacific oscillation can create changes in the Pacific Ocean and lower atmosphere on decadal time scales. Climate change occurs when changes of Earth's climate system result in new weather patterns that remain for an extended period of time. This duration of time can be as brief as

986-471: Is sometimes modeled as a stochastic process but this is generally accepted as an approximation to processes that are otherwise too complicated to analyze. The collection of a long record of climate variables is essential for the study of climate. Climatology deals with the aggregate data that meteorologists have recorded. Scientists use both direct and indirect observations of the climate, from Earth observing satellites and scientific instrumentation such as

1044-491: Is sometimes termed hydroclimatology, in particular when studying the effects of climate change on the water cycle. The study of contemporary climates incorporates meteorological data accumulated over many years, such as records of rainfall, temperature and atmospheric composition. Knowledge of the atmosphere and its dynamics is also embodied in models , either statistical or mathematical , which help by integrating different observations and testing how well they match. Modeling

1102-435: Is the study of climate as related to human history and is thus concerned mainly with the last few thousand years. Boundary-layer climatology concerns exchanges in water, energy and momentum near surfaces. Further identified subtopics are physical climatology, dynamic climatology, tornado climatology , regional climatology, bioclimatology , and synoptic climatology. The study of the hydrological cycle over long time scales

1160-441: Is used for understanding past, present and potential future climates. Climate research is made difficult by the large scale, long time periods, and complex processes which govern climate. Climate is governed by physical principles which can be expressed as differential equations . These equations are coupled and nonlinear, so that approximate solutions are obtained by using numerical methods to create global climate models . Climate

1218-584: The Antarctic Circumpolar Current . Given the strength and proximity of the Gulf Stream, beaches along the East Coast of the United States may be more vulnerable to large sea-level anomalies, which significantly impact rates of coastal erosion . The Gulf Stream is typically 100 km (62 mi) wide and 800 to 1,200 m (2,600 to 3,900 ft) deep. The current velocity is fastest near

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1276-647: The Caribbean Sea , while a second, the Antilles Current , flows north and east of the West Indies . These two branches rejoin north of the Straits of Florida. The trade winds blow westwards in the tropics, and the westerlies blow eastwards at mid-latitudes. This wind pattern applies a stress to the subtropical ocean surface with negative curl across the north Atlantic Ocean. The resulting Sverdrup transport

1334-706: The El Niño–Southern Oscillation (ENSO), the Madden–Julian oscillation (MJO), the North Atlantic oscillation (NAO), the Arctic oscillation (AO), the Pacific decadal oscillation (PDO), and the Interdecadal Pacific Oscillation (IPO). Climate models are used for a variety of purposes from studying the dynamics of the weather and climate system to predictions of future climate. The Greeks began

1392-517: The Köppen climate classification , was developed during the late nineteenth century and is based on vegetation. It uses monthly data concerning temperature and precipitation . There are different types of variability: recurring patterns of temperature or other climate variables. They are quantified with different indices. Much in the way the Dow Jones Industrial Average , which is based on

1450-661: The North Atlantic Current . The process of western intensification causes the Gulf Stream to be a northward-accelerating current off the east coast of North America. Around 40°0′N 30°0′W  /  40.000°N 30.000°W  / 40.000; -30.000 , it splits in two, with the northern stream, the North Atlantic Drift, crossing to Northern Europe and the southern stream, the Canary Current , recirculating off West Africa. The Gulf Stream influences

1508-482: The climate system , such as the widespread melt of glaciers , sea level rise and shifts of flora and fauna. In contrast to meteorology , which emphasises short term weather systems lasting no more than a few weeks, climatology studies the frequency and trends of those systems. It studies the periodicity of weather events over years to millennia, as well as changes of long-term average weather patterns in relation to atmospheric conditions. Climatologists study both

1566-531: The western coastal islands of Scotland . A noticeable effect of the Gulf Stream and the strong westerly winds on Europe occurs along the Norwegian coast . Northern parts of Norway lie close to the Arctic zone, most of which is covered with ice and snow in winter. However, almost all of Norway's coast remains free of ice and snow throughout the year. The warming effect provided by the Gulf Stream has allowed fairly large settlements to be developed and maintained on

1624-656: The Caribbean and then either move in a northward direction and curve towards the eastern coast of the United States or stay on a north-westward track and enter the Gulf of Mexico . Such storms have the potential to create strong winds and extensive damage to the United States' Southeast coastal areas . Hurricane Sandy in 2012 was a recent example of a hurricane tracking along the Gulf Stream and gaining strength. Strong extratropical cyclones have been shown to deepen significantly along

1682-473: The Earth's land surface areas). Topics that climatologists study comprise three main categories: climate variability , mechanisms of climatic change, and modern changes of climate. Various factors affect the average state of the atmosphere at a particular location. For instance, midlatitudes will have a pronounced seasonal cycle of temperature whereas tropical regions show little variation of temperature over

1740-699: The Earth. Any unbalance results in a change of the average temperature of the Earth. Most climate models include the radiative effects of greenhouse gases such as carbon dioxide . These models predict a trend of increase of surface temperatures , as well as a more rapid increase of temperature at higher latitudes. Models can range from relatively simple to complex: Additionally, they are available with different resolutions ranging from >100 km to 1 km. High resolutions in global climate models are computational very demanding and only few global datasets exists. Examples are ICON or mechanistically downscaled data such as CHELSA (Climatologies at high resolution for

1798-648: The Gulf Stream will not shut down in a warming climate. While the Gulf Stream is expected to slow down as the Atlantic Meridional Overturning Circulation (AMOC) weakens, it will not collapse, even if the AMOC were to collapse. Nevertheless, this slowing down will have significant effects, including a rise in sea level along the North American coast, reduced precipitation in the midlatitudes, changing patterns of strong precipitation around Europe and

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1856-400: The atmosphere, oceans, land surface, and ice. 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

1914-483: The climate of the coastal areas of the East Coast of the United States from Florida to southeast Virginia (near 36°N latitude), and to a greater degree, the climate of Northwest Europe. A consensus exists that the climate of Northwest Europe is warmer than other areas of similar latitude at least partially because of the strong North Atlantic Current. It is part of the North Atlantic Gyre . Its presence has led to

1972-552: The climate system is warming. If more energy goes out, the energy budget is negative and earth experiences cooling. Climate change also influences the average sea level . Modern climate change is caused largely by the human emissions of greenhouse gas from the burning of fossil fuel which increases global mean surface temperatures . Increasing temperature is only one aspect of modern climate change, which also includes observed changes of precipitation , storm tracks and cloudiness. Warmer temperatures are causing further changes of

2030-590: The coast of Northern Norway , including Tromsø , the third-largest city north of the Arctic Circle. Weather systems warmed by the Gulf Stream drift into Northern Europe, also warming the climate behind the Scandinavian Mountains . The possibility of a Gulf Stream collapse has been covered by some news publications. The IPCC Sixth Assessment Report addressed this issue specifically, and found that based on model projections and theoretical understanding,

2088-520: The course of the Gulf Stream for use in sending mail from North America to Europe. Francis Galton (1822–1911) invented the term anticyclone . Helmut Landsberg (1906–1985) fostered the use of statistical analysis in climatology. During the early 20th century, climatology mostly emphasized the description of regional climates. This descriptive climatology was mainly an applied science, giving farmers and other interested people statistics about what

2146-605: The current, although seaweed lies in clusters to its east. In April 2018, two studies published in the British scientific journal Nature found the Gulf Stream to be at its weakest for at least 1,600 years. The Gulf Stream is influential on the climate of the Florida peninsula . The portion off the Florida coast, referred to as the Florida Current , maintains an average water temperature of at least 24 °C (75 °F) during

2204-482: The decades that followed, and while the history of climate change science started earlier, climate change only became one of the main topics of study for climatologists during the 1970s and afterward. Various subtopics of climatology study different aspects of climate. There are different categorizations of the sub-topics of climatology. The American Meteorological Society for instance identifies descriptive climatology, scientific climatology and applied climatology as

2262-550: The development of strong cyclones of all types, both within the atmosphere and within the ocean. European discovery of the Gulf Stream dates to the 1512 expedition of Juan Ponce de León , after which it became widely used by Spanish ships sailing from the Caribbean to Spain. A summary of Ponce de León's voyage log on April 22, 1513, noted, "A current such that, although they had great wind, they could not proceed forwards, but backwards and it seems that they were proceeding well; at

2320-558: The end, it was known that the current was more powerful than the wind." Benjamin Franklin became interested in the North Atlantic Ocean circulation patterns. In 1768, while in England, Franklin heard a curious complaint from the Colonial Board of Customs : "Why did it take British packets several weeks longer to reach New York from England than it took an average American merchant ship to reach Newport, Rhode Island , despite

2378-846: The formal study of climate; in fact, the word "climate" is derived from the Greek word klima , meaning "slope", referring to the slope or inclination of the Earth's axis. Arguably the most influential classic text concerning climate was On Airs, Water and Places written by Hippocrates about 400 BCE . This work commented on the effect of climate on human health and cultural differences between Asia and Europe. This idea that climate controls which populations excel depending on their climate, or climatic determinism , remained influential throughout history. Chinese scientist Shen Kuo (1031–1095) inferred that climates naturally shifted over an enormous span of time, after observing petrified bamboos found underground near Yanzhou (modern Yan'an , Shaanxi province),

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2436-481: The future. Some refer to this type of forecasting as pattern recognition, which remains a useful method of estimating rainfall over data voids such as oceans using knowledge of how satellite imagery relates to precipitation rates over land, as well as the forecasting of precipitation amounts and distribution of the future. A variation of this theme, used for medium range forecasting, is known as teleconnections , when systems in other locations are used to help determine

2494-555: The globe. Classification is an important method of simplifying complicated processes. Different climate classifications have been developed over the centuries, with the first ones in Ancient Greece . How climates are classified depends on what the application is. A wind energy producer will require different information (wind) in a classification than someone more interested in agriculture, for whom precipitation and temperature are more important. The most widely used classification,

2552-516: The location of a system within the regime surrounding. One method of using teleconnections are by using climate indices such as ENSO-related phenomena. Gulf Stream The Gulf Stream is a warm and swift Atlantic ocean current that originates in the Gulf of Mexico and flows through the Straits of Florida and up the eastern coastline of the United States, then veers east near 36°N latitude (North Carolina) and moves toward Northwest Europe as

2610-470: The mainland in winter just 30 miles to the north. North of Nantucket Island along the New England coast northward to the eastern Canadian coast the cold Labrador Current is found. The North Atlantic Current of the Gulf Stream, along with similar warm air currents, helps keep Ireland and the western coast of Great Britain a few degrees warmer than the east. However, the difference is most dramatic in

2668-659: The merchant ships leaving from London and having to sail down the River Thames and then the length of the English Channel before they sailed across the Atlantic, while the packets left from Falmouth in Cornwall?" Franklin asked his cousin Timothy Folger, a Nantucket Island whaling captain, for an answer. Folger explained that merchant ships routinely crossed the current—which was identified by whale behaviour, measurement of

2726-406: The nature of climates – local, regional or global – and the natural or human-induced factors that cause climates to change. Climatology considers the past and can help predict future climate change . Phenomena of climatological interest include the atmospheric boundary layer , circulation patterns , heat transfer ( radiative , convective and latent ), interactions between the atmosphere and

2784-413: The normal weather was and how great chances were of extreme events. To do this, climatologists had to define a climate normal , or an average of weather and weather extremes over a period of typically 30 years. While scientists knew of past climate change such as the ice ages , the concept of climate as changing only very gradually was useful for descriptive climatology. This started to change during

2842-566: The ocean's surface. The Gulf Stream periodically forms rings resulting from a meander of the Gulf Stream being closed off from an alternate route distinctive from that meander, creating an independent eddy. These eddies have two types - cold-core rings, which rotate cyclonically (counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere), and warm-core rings, which rotate anticyclonically. These rings have

2900-403: The oceans and land surface (particularly vegetation, land use and topography ), and the chemical and physical composition of the atmosphere. A relative difficult method of forecast, the analog technique requires remembering a previous weather event which is expected to be mimicked by an upcoming event. What makes it a difficult technique is that there is rarely a perfect analog for an event of

2958-434: The stock prices of 30 companies, is used to represent the fluctuations of stock prices in general, climate indices are used to represent the essential elements of climate. Climate indices are generally devised with the twin objectives of simplicity and completeness, and each index typically represents the status and timing of the climate factor it represents. By their very nature, indices are simple, and combine many details into

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3016-447: The surface, with the maximum speed typically about 2.5 m/s (5.6 mph). As it travels north, the warm water transported by the Gulf Stream undergoes evaporative cooling. The cooling is wind-driven; wind moving over the water causes evaporation , cooling the water and increasing its salinity and density. When sea ice forms, salts are left out of the ice, a process known as brine exclusion. These two processes produce water that

3074-511: The three subcategories of climatology, a categorization based on the complexity and the purpose of the research. Applied climatologists apply their expertise to different industries such as manufacturing and agriculture . Paleoclimatology is the attempt to reconstruct and understand past climates by examining records such as ice cores and tree rings ( dendroclimatology ). Paleotempestology uses these same records to help determine hurricane frequency over millennia. Historical climatology

3132-523: The tropics, and stronger storms in the North Atlantic. The warm water and temperature contrast along the edge of the Gulf Stream often increase the intensity of cyclones, tropical or otherwise. Tropical cyclone generation normally requires water temperatures in excess of 26.5 °C (79.7 °F). Tropical cyclone formation is common over the Gulf Stream, especially in July. Storms travel westward through

3190-452: The warm waters of the Gulf Stream, tropical fish are often encountered off the East Coast as they search for food, including several species of Batoidea , Dolphin , Barracuda , and Triggerfish . The Gulf Stream's proximity to Nantucket , Massachusetts , adds to its biodiversity , because it is the northern limit for southern varieties of plant life, and the southern limit for northern plant species, Nantucket being warmer during winter than

3248-532: The water's temperature, and changes in the water's colour—while the mail packet captains ran against it. Franklin had Folger sketch the path of the current on a chart of the Atlantic and add notes on how to avoid the current when sailing from England to America. Franklin then forwarded the chart to Anthony Todd, secretary of the British Post Office. Franklin's Gulf Stream chart was printed in 1769 in London, but it

3306-537: The winter, and often 29 °C (84 °F) in summer and fall. East winds moving over this warm water move warm air from over the Gulf Stream inland, helping to keep temperatures milder across the state than elsewhere across the Southeastern United States during the winter. The Gulf Stream carries a wide variety of tropical fish and organisms northward along the East Coast from Florida to extreme southeast Massachusetts in spring and summer. Following

3364-581: Was mostly ignored by British sea captains. A copy of the chart was printed in Paris circa 1770–1773, and a third version was published by Franklin in Philadelphia in 1786. The Gulf Stream proper is a western-intensified current, driven largely by wind stress . In 1958, oceanographer Henry Stommel noted, "very little water from the Gulf of Mexico is actually in the stream". The North Atlantic Current , in contrast,

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