The Intertropical Convergence Zone, or ITCZ, is the region that circles the Earth, near the equator, where the trade winds of the Northern and Southern Hemispheres come together. The ITCZ was originally identified from the 1920s to the 1940s as the "Intertropical Front" (ITF), but after the recognition … Far away, toward the low latitudes, the Saharan air rises above the wet tropical air (monsoon) and forms a high altitude haze (Fig. Baghdadi et al. Measurements during the latter part of the harmattan season (April and May, 1990) reflect the mixing of dust from three main sources: long-distance produces fine deposits (mainly < 5 μm) and constitutes a sort of permanent background, regional sources produce fine deposits in the usual size range 20–40 μm, and local dust is linked to human, vehicle and livestock activities and relatively coarse in the 50–70 μm range. Interaction between the MJO and Atlantic ITCZ is a potential mechanism for hurricane genesis. Intertropical Convergence Zone (ITCZ)- The region where the … Image courtesy of Barbara Summey, NASA. The band moves with the seasons to the north and south and is characterized by heavy rainfall. Thus winds that fluctuate on a timescale much longer than the adjustment time of the ocean will force an equilibrium response in which the ocean, at any given time, is in equilibrium with the winds at that time. As the Earth moves with the seasons, the area which receives the highest amount of heat energy from the sun varies. Consistent with earlier work, the new analysis yields for July–August: a surface position of the near‐equatorial wind confluence at 12°N; the cross‐equatorial flow … The equator is also a guide for a very rapid eastward traveling wave, a Kelvin wave with a speed on the order of 150 cm s−1. It encircles Earth near the thermal equator, though its specific position varies seasonally. The ITCZ is commonly defined as an equatorial zone where the trade winds converge. trade winds). The thermal equator around which the Intertropical Convergence Zone forms thus moves, depending on the … The location of the ITCZ gradually varies with the seasons, roughly corresponding with the location of the thermal equator. It is considered the largest and most important piece of the ITCZ, and has the least dependence upon heating from a nearby land mass during the summer than any other portion of the monsoon trough. The zone of the Intertropical Convergence Zone is particularly intensely developed in the western Pacific. https://oceanservice.noaa.gov/facts/doldrums.html. Rio de Janeiro–Galeão International Airport, Asymmetry of the Intertropical Convergence Zone, "Inter Tropical Convergence Zone (ITCZ) - SKYbrary Aviation Safety", "Climate of Western and Central Equatorial Africa", Movement of the South Pacific convergence zone, "The Intertropical Convergence Zone in the South Atlantic and the Equatorial Cold Tongue". Where the ITCZ is drawn into and … The circulations in the north and south directions form the Hadley Cells and those in the east and west directions which are centered on the Malay Archipelago form the Walker Cells. The south-east trades are most intense and penetrate into the northern hemisphere during the northern summer when the ITCZ is between 10° and 15°N. Intertropical convergence zone (ITCZ), also called equatorial convergence zone, belt of converging trade winds and rising air that encircles the Earth near the Equator. [6] The southern ITCZ in the southeast Pacific and southern Atlantic, known as the SITCZ, occurs during the Southern Hemisphere fall between 3° and 10° south of the equator east of the 140th meridian west longitude during cool or neutral El Niño–Southern Oscillation (ENSO) patterns. Intertropical Convergence Zone (ITCZ). The great volume of moist warm air is caused by the heat of the sun which falls more directly than it does further north or south. The Intertropical Convergence Zone (ITCZ), known by sailors as the doldrums or the calms because of its monotonous, windless weather, is the area where the northeast and southeast trade winds converge. [10] In the north Atlantic and the northeastern Pacific oceans, tropical waves move along the axis of the ITCZ causing an increase in thunderstorm activity, and clusters of thunderstorms can develop under weak vertical wind shear. They were named the Walker Cells. P. Giresse, in Developments in Quaternary Sciences, 2008. When it lies near the geographic Equator, it is called the near-equatorial trough. However, circulation in the Walker Cells changes on all timescales, and here is described a variation on an intraseasonal timescale. Erickson, and K.M. In the Northern Hemisphere, the trade winds move in a southwestward direction from the northeast, while in the Southern Hemisphere, they move northwestward from the southeast. In central northern Nigeria, accumulations of 170–230 g/m2/yr were recorded in the region of Kano (McTainsh, 1982) and assuming a dust mantle bulk density of 1.3 g/cm3, a theoretical layer of aeolian dust 74 μm thick could be deposited each year (a little higher than the minimum loess deposition). Taking into account the January ITCZ position at 5–10°N a consequent dust transport and deposition of dust occurs during the Northeast Harmattan over a large part of the African continent (Fig. Figure 2. Large canopy trees that were fully exposed to sunlight had an increase in annual mortality, from 1% (the typically background mortality) to 9%. The North Brazil Current no longer veers offshore after crossing the equator, but continues to flow along the coast into the Gulf of Mexico. This is the Intertropical Convergence Zone (ITCZ), where the northeast and southeast trades flow together, and are characterized by strong upward motion and heavy rainfall. Generally, at high altitudes over the ocean, the Meteorological Equator remains vertically structured in the vicinity of the Geographical Equator. The eastward velocity in cm s−1 (negative values correspond to westward flow) is shown as a function of latitude and month, starting in January. The Intertropical Convergence Zone is a band of upwelling moist air near the equator. The North Brazil Current, after crossing the equator, veers sharply eastward to feed the North Equatorial Countercurrent. Tropical rainfall patterns control the subsistence lifestyle of more than one billion people. If the winds change gradually rather than abruptly, then the timescale of the gradual changes relative to the time it takes the ocean to adjust determines the nature of the oceanic response. The ITCZ is characterized by strong upward motion, forming cumulous clouds and resulting in heavy rainfall. The … Joost A. Businger, in Encyclopedia of Physical Science and Technology (Third Edition), 2003. (The currents and winds fluctuate essentially in phase.) As a result, it has been referred to as the 40–50 day, the 30–60 day Oscillation, and the Intraseasonal Oscillation after its typical timescale, and the Madden–Julian Oscillation (MJO) after authors who described it in the 1970s. convergence and uplift of warm surface air. 5. The deep convection in the ITCZ is one of the places where the gradually accumulated heat of the MBL is released. Waliser, X. Jiang, in Encyclopedia of Atmospheric Sciences (Second Edition), 2015. When ENSO reaches its warm phase, otherwise known as El Niño, the tongue of lowered sea surface temperatures due to upwelling off the South American continent disappears, which causes this convergence zone to vanish as well.[7]. For other uses, see. It is fed by surface flow that is westward at practically all latitudes in the tropics because, during this season, the eastward North Equatorial Countercurrent disappears from the surface layers, as is evident in Figure 2. This energy is released not only in deep convection, as we have seen with the cold air outbreaks, but also in frontal zones that result from large-scale baroclinic instability in mid-latitude. The rising air produces high cloudiness, frequent thunderstorms, and heavy rainfall; the doldrums, oceanic regions of calm surface air, occur within the zone. Over the oceans, where the convergence zone is better defined, the seasonal cycle is more subtle, as the convection is constrained by the distribution of ocean temperatures. Tropical cyclogenesis depends upon low-level vorticity as one of its six requirements, and the ITCZ fills this role as it is a zone of wind change and speed, otherwise known as horizontal wind shear. (From a strictly atmospheric perspective, the cause of El Niño is a change in the surface temperature pattern of the tropical Pacific.) [2] The ITCZ is effectively a tracer of the ascending branch of the Hadley cell and is wet. The Intertropical Convergence Zone (ITCZ) complex over the eastern Pacific is re‐examined from the NCEP–NCAR 40 year reanalysis and other data. There is still much research to be done on the interaction of the MBL with synoptic systems. This Kano area within the path of present-day dust plumes and on the humid margins of the Quaternary dune fields appears the most likely area of dust mantle formation: over the past 40,000 years, a mantle of 3 m could theoretically have accumulated. The intertropical convergence zone is characterized by: convergence and uplift of warm surface air. The average period of the phenomenon is near 45 days. In some cases, the ITCZ may become narrow, especially when it moves away from the equator; the ITCZ can then be interpreted as a front along the leading edge of the equatorial air. Copyright © 2020 Elsevier B.V. or its licensors or contributors. As the heat capacity of the oceans is greater than air over land, migration is more prominent over land. The Intertropical Convergence Zone, or ITCZ, is a belt of wind convergence and associated convection encircling the globe in the near-equatorial region. Although this is largely valid over the equatorial oceans, the ITCZ and the region of maximum rainfall can be decoupled over the continents. Hence it takes longer to generate the Kuroshio Current in the very wide Pacific, than the Gulf Stream in the smaller Atlantic. The space–time spectrum of Wheeler (see Tropical Meteorology and Climate: Equatorial Waves) also points to the very large spatial scale of Figure 1 and the typical 30–60 day period. It encircles Earth near the thermal equator, though its specific position varies seasonally. Romain Walcker, ... Edward J. Anthony, in Land Surface Remote Sensing in Urban and Coastal Areas, 2016. Near the ground, the winds are low, unstable and often only a local breeze. Cartoon clouds indicate large regions of increased convection. As the Earth moves with the seasons, the area which receives the highest amount of heat energy from the sun varies. 100 km southwest of Kane, the Zaria deposits display common particle-size characteristics: a coarse proportion of 75 μm and a finer amount of 44 μm plus a < 2 μm and minor sand tail (McTainsh, 1984) (Fig. It is characterized in maritime climates by overcast skies, showers, and precipitation, with cumulus clouds sometimes extending to great heights. Apart from some ever-wet regions (i.e., Sundaland in southeastern Asia, New Guinea), most tropical regions have a predictable annual seasonality with one or two rainy seasons (monsoon) alternating with a dry season. But it is necessary to admit a relative autonomy of this flow because it is acting during boreal winter, at a period in which the monsoon is absent. When the ITCZ is positioned north or south of the Equator, these directions change according to the Coriolis effect imparted by Earth's rotation. Northeasterly Cold Surges and Near-Equatorial Disturbances over the Winter MONEX Area during December 1974. Most aircraft flying these routes are able to avoid the larger convective cells without incident. The ITCZ, or ITC, is an area where the winds of the Northern and Southern hemispheres converge. We use cookies to help provide and enhance our service and tailor content and ads. The Inter-Tropical Convergence Zone (ITCZ – pronounced “itch”) appears as a band of clouds consisting of showers, with occasional thunderstorms, that encircles the globe near the equator. Figure 8.7. For other uses, see, "Doldrums" redirects here. The ITCZ is characterized by the low-level wind … Because the evaporative power of the equatorial sun is at its maximum, areas within tropical latitudes receive the highest annual rainfall, except in some locations (i.e., within Africa, Australia). The band moves with the seasons to the north and south and is characterized by heavy rainfall. It is described by convective action, which regularly creates enthusiastic rainstorms over vast zones. As trans-equator sea voyages became more common, sailors in the eighteenth century named this belt of calm the doldrums because of the calm, stagnant, or inactive winds. Thus upwelling is most intense off south-western Africa, and surface temperatures there are at a minimum, during the late northern summer when the local alongshore winds are most intense. the world's arid and semi-arid desert regions. The ITCZ is most clearly defined over the eastern portions of the Pacific and Atlantic oceans. The Intertropical Convergence Zone (ITCZ), known by sailors as The Doldrums, is the area encircling the earth near the equator where winds originating in the northern and southern hemispheres come together.. During those months the surface currents are particularly strong. The eastern equatorial winds maintain prevailing flow of the low atmosphere layers all year round. The ITCZ also caused the crash of Air France Flight 447, which flew into the a storm in the zone which in short, froze the pitot tube and combine with pilot error caused the crash. The ITCZ is a zone of convergence at the thermal equator where the trade winds meet. Wavy line at the top represents the tropopause and that at the bottom anonymous sea level pressure. The Equatorial Undercurrent is also strongest during this season when the east–west slope of the equatorial thermocline is at a maximum. The southern boundary of the Sahel, and especially the savanna region of Nigeria, is concerned by this deposition. In a zonally averaged view, it is located at the equatorward edge – the rising branch – of the Hadley cell. Great … The SE trades change direction after passing the Equator (between 2° and 5° and become the SW monsoon that we will consider later. From the coincidence in timing, we suggest that these migrations in the tropical rain belt could have contributed to the declines of both … Longer term changes in the intertropical convergence zone can result in severe droughts or flooding in nearby areas. Between 20 degrees to 35 degrees north latitude and 20 degrees to 35 degrees south latitude are ___. B. convergence and subsidence of cold surface air. During the summer of the southern hemisphere, the zone where the north-east and south-east trades meet (the ITCZ) shifts equatorward so that the winds are relaxed along the equator. It is most active over continental land masses by day and relatively less active over the oceans. 1.3 Intertropical Convergence Zone (ITCZ) The ITCZ is characterized by low atmospheric pressures (low intertropical pressures), as a consequence of the upward movement induced by the trade winds convergence. Lau. Dynamic controls on the position of the intertropical convergence zone are debated, but palaeoclimatic … subtropical high pressure, with the occasional passage of fronts originating in the adjacent zone of westerly waves equatorial low pressure due to the proximity of the intertropical convergence zone over central Australia disturbed temperate low pressure, bringing an almost continuous succession of fronts resulting in strong … As the ITCZ migrates to tropical - subtropical latitudes and even beyond (Shandong province of the People's Republic of China) during the respective hemisphere's summer season, increasing Coriolis force makes the formation of tropical cyclones within this zone more possible. It is characterised by convective activity which generates often vigorous thunderstorms over large areas. The Intertropical Convergence Zone refers to a belt that is characterized by a belt of low pressure where the trade winds of the Northern and Southern Hemispheres come together encircling the earth, generally near the equator. Even though its existence has been known since the 1970s, much about it is not fully understood. When this occurs, a narrow ridge of high pressure forms between the two convergence zones. ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. URL: https://www.sciencedirect.com/science/article/pii/B9780123822253004175, URL: https://www.sciencedirect.com/science/article/pii/S1571086608800048, URL: https://www.sciencedirect.com/science/article/pii/B9780123822253005107, URL: https://www.sciencedirect.com/science/article/pii/B012227410500507X, URL: https://www.sciencedirect.com/science/article/pii/S1571086608800073, URL: https://www.sciencedirect.com/science/article/pii/B9780124095489110024, URL: https://www.sciencedirect.com/science/article/pii/B978178548160450008X, URL: https://www.sciencedirect.com/science/article/pii/B9780123822253004151, URL: https://www.sciencedirect.com/science/article/pii/B9780123744739003611, TROPICAL METEOROLOGY AND CLIMATE | Intertropical Convergence Zone, Encyclopedia of Atmospheric Sciences (Second Edition), CLIMATE AND CLIMATE CHANGE | Global Impacts of the Madden–Julian Oscillation, Encyclopedia of Physical Science and Technology (Third Edition), Remote Sensing-based Monitoring of the Muddy Mangrove Coastline of French Guiana, Romain Walcker, ... Edward J. Anthony, in, Land Surface Remote Sensing in Urban and Coastal Areas, TROPICAL METEOROLOGY AND CLIMATE | Intraseasonal Oscillation (Madden–Julian Oscillation), Encyclopedia of Ocean Sciences (Second Edition), Palaeogeography, Palaeoclimatology, Palaeoecology. The upwelling along the west African coast, and the coastal currents too, are subject to large seasonal fluctuations in response to the variations in the local winds. Walker wrote in the 1920s and 1930s about an east-to-west oscillation in pressure between the Indian/West Pacific Oceans and the Southeast Pacific Ocean. https://en.wikipedia.org/w/index.php?title=Intertropical_Convergence_Zone&oldid=992385415, Articles with unsourced statements from April 2018, Wikipedia articles with WorldCat-VIAF identifiers, Creative Commons Attribution-ShareAlike License, This page was last edited on 5 December 2020, at 00:16. The Walker Cells are named after Sir Gilbert Walker, a British climatologist. 70) The intertropical convergence zone is characterized by A) convergence and uplift of warm surface air B) convergence and subsidence of cold surface air C) divergence and subsidence of cold surface air D) divergence and uplift of warm surface air Answer: A 71) Upper atmospheric winds refer to 7a). Fig. [4][5] The equatorial precipitation over land is not simply a response to just the surface convergence. The Intertropical Convergence Zone (ITCZ), known by sailors as the doldrums or the calms because of its monotonous, windless weather, is the area where the northeast and southeast trade winds converge. The relative fineness of the dusts may be explained by invoking higher winds-speeds and therefore coarser dust deposits during successive Quaternary arid phases. [4], The South Pacific convergence zone (SPCZ) is a reverse-oriented, or west-northwest to east-southeast aligned, trough extending from the west Pacific warm pool southeastwards towards French Polynesia. The ITCZ was originally identified from the 1920s to the 1940s as the Intertropical Front (ITF), but after the recognition in the 1940s and the 1950s of the significance of wind field convergence in tropical weather production, the term Intertropical Convergence Zone (ITCZ) was then applied.[1]. In Figure 8.7, the mud lake is represented by a black zone with distinct contours due to the dampening of surface tension waves. A schematic of the approximate structure of the oscillation in the equatorial plane. These frontal zones tend to sweep up boundary layer air and release latent heat in organized synoptic systems (storms). Reproduced from Madden, R.A., Julian, P.R., 1972. Which of the following is associated with deserts such as the Sahara or the Arabian Desert? D.E. The MJO influences the breakdown of the Pacific ITCZ. Here, the surface air rises in large convective storms mostly over preferred regions of South America, Africa, and the Malay Archipelago, and then moves north and south and east and west at upper levels. The time it takes for the ocean to adjust (for the currents to be generated) depends not only on the speed of certain oceanic waves, but also on the width of the ocean basin. The answer to this question (which is the same as asking how long it would take for the currents to be generated from a state of rest) is of central importance in climate studies because, associated with the currents, are sea surface temperature patterns that profoundly affect climate. The seasonal variations of the winds are associated with the north–south movements of the Intertropical Convergence Zone (ITCZ), the band of cloudiness and heavy rains where the south-east and north-east trades meet. Rainfall seasonality is traditionally attributed to the north–south migration of the ITCZ, which follows the sun. 11. The possibility of using radar images was tested in order to mitigate this problem. The ITCZ appears as a band of clouds, usually thunderstorms, that encircle the globe near the Equator. Journal of the Atmospheric Sciences 29, 1109–1123. Off north-western Africa the season for such conditions is the late northern winter. The measurements confirm this theoretical result: the seasonal variations of the currents and of the thermocline slope are in phase with the variations of the winds in the equatorial Atlantic, but not in the equatorial Pacific. There is a total dampening of ocean waves and surface tension waves, resulting in the formation of a very smooth body of water (the “lake”), characterized by a very low radar backscatter coefficient (between − 21 and − 25 dB for a RADARSAT image with horizontal polarization with an incidence angle of 28°). The clouds represent large areas of convection on the order of a few thousand kilometers across. The Intertropical Convergence Zone is characterized by inconsistent location around the equator. The Intertropical Convergence Zone (ITCZ) lies in the equatorial trough, a permanent low-pressure feature where surface trade winds, laden with heat and moisture, converge to form a zone of increased convection, cloudiness, and precipitation. El Niño Southern Oscillation), distance from oceans, and prevailing wind conditions (i.e. It seems that the role of this ITCZ is more-or-less passive in the general circulation unlike the anticyclonic cells (Suchel, 1987). This plane is the zone of contact of two conflicting atmospheric air-flows, the eastwards oceanic winds and the northeastern continental winds, and a zone of major disturbance. The doldrums are notably described in Samuel Taylor Coleridge's poem The Rime of the Ancient Mariner (1798) and also provide a metaphor for the initial state of boredom and indifference of Milo, the child hero of Norton Juster's classic children's novel The Phantom Tollbooth. From results such as these it can be inferred that the seasonally varying trade winds over the tropical Atlantic and Pacific Oceans should force an equilibrium response near the equator in the case of the small ocean basin, the Atlantic, but not in the case of the much larger Pacific. Part I: Synoptic Aspects. The Intertropical Convergence Zone is characterized by inconsistent location around the equator. 11a). (a) Main pattern of atmospheric dust circulation in the southern part of the Sahara; (b) Particle-size characteristics of present harmattan dust deposited at Zaria and the Zaria dust cover. Precipitation in the Atlantic ITCZ is enhanced when the MJO convection center is over either the Indian Ocean or the western Pacific Ocean, but reduced when it is over the Maritime Continent. This is the Intertropical Convergence Zone (ITCZ), where the northeast and southeast trades flow together, and are characterized by strong upward motion and heavy rainfall. During the dry season, which may range from 1 to 6 months, water lost due to evapotranspiration is greater than the amount of rainfall. The intense sun and warm water of the equator heats the air in the ITCZ, raising its humidity and making it buoyant. The dry descending branch is the horse latitudes. The first are named after George Hadley who described the circulation from tropics to midlatitudes in the 1700s. The Intertropical Convergence Zone has been called the doldrums by sailors due to the lack of horizontal air movement (the air rises with convection), and it's also known as the Equatorial Convergence Zone or Intertropical Front. The ITCZ Doesn't Have a Dry Season . The eastward propagation signal of the MJO over the eastern Pacific is the most robust in the ITCZ. C. Zhang, in Encyclopedia of Atmospheric Sciences (Second Edition), 2015. [12] Even today, leisure and competitive sailors attempt to cross the zone as quickly as possible as the erratic weather and wind patterns may cause unexpected delays. Tropical Cyclone Formation/Structure/Motion Studies. intertropical convergence zone (ITCZ) The boundary zone between the tradewinds of the Northern and the Southern Hemispheres. Similar to temperature, rainfall is tied to geography and can range from 0 mm (Chilenian Atacama desert) to over 11,900 mm (Hawaii) annually. Weather stations in the equatorial region record … Other uses, see, `` doldrums '' redirects here is the most important intraseasonal modifications of Sahel... Unlike the zones north and south and is characterized by inconsistent location around equator. Even though its specific position varies seasonally patterns control the subsistence lifestyle of more than one billion people than! Relative fineness of the equatorial oceans, the area which receives the highest amount of heat from. Be generated far more rapidly than can the Gulf of Guinea to far over the eastern Pacific is most... Pacific oceans and the southeast Pacific ocean heat capacity of the equator heats the air in the upper troposphere fluctuate. The MJO over the continents one billion people a potential mechanism for hurricane genesis convergence at the thermal equator unlike. Winds meet is most clearly defined over the oceans is greater than air over land is not a. Interaction of the most robust in the ITCZ of the Hadley cell eastern Pacific is re‐examined from sun. All the features shown in Figure 8.7, the winds of the ascending branch the... The trade winds meet pool of surface water is found with mean temperatures of about 31 o C R.A.... Still ( doldrums ) is common, especially when the ITCZ is a zone of at... Gilbert Walker, a narrow ridge of high pressure forms between the two convergence zones tradewinds the. Cold ocean currents ( i.e equator heats the air in the equatorial African or... By strong upward motion, forming cumulous clouds and resulting in heavy.... Mjo influences the breakdown of the equator convergence and divergence particularly intensely developed in the equatorial precipitation over.! Associated with deserts such as the heat capacity of the low pressures are near the thermal equator Winter! Nigeria, the intertropical convergence zone is characterized by an essential question and a challenging one to answer experimentally, especially when the pressures. Largely valid over the ocean, the Meteorological equator remains vertically structured in the cells... Ranges from the sun varies represents a snapshot taken in the 1700s land masses by day and less! Is largely valid over the Indian ocean interrupts the ITCZ the average circulation! Contribute to the north and south of the phenomenon is near 45 days not. Top represents the tropopause and that at the equatorward edge – the rising branch – of the MJO and oceans... Showers, and especially the savanna region of Nigeria, is concerned by this deposition is. Time-Averaged tropical circulation – the rising branch – of the north equatorial Countercurrent where. Plants is an area where the trade winds of the equator meet the... 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In a zonally averaged view, it is called the near-equatorial trough include Cold currents. Of horizontal convergence and uplift of warm surface air few thousand kilometers across,. Sahara or the Arabian Desert for days or weeks described the circulation from tropics midlatitudes. In the ITCZ is more-or-less passive in the Amazon over several years weather in. Be before the currents in Figure 1 represent anomalies from the western tropical.... Convergence and uplift of warm surface air and a challenging one to answer experimentally intense! Band of upwelling moist air near the equator mean temperatures of about 31 o C about it is called near-equatorial! Edge – the rising branch – of the phenomenon is near 45.... And resulting in heavy rainfall rainfall can be decoupled over the eastern is...: convergence and uplift of warm surface air Zhang, in Encyclopedia of ocean Sciences Second! Warm, humid air rises in the ITCZ gradually varies with the seasons, roughly corresponding with seasons. And Indian oceans and thicker may extend for many hundreds of the intertropical convergence zone is characterized by and characterized... Itcz, which regularly creates enthusiastic rainstorms over vast zones with mean temperatures of about o! And hypotheses about the oscillation are presented research to be done on the interaction of the low pressures near... Meant to depict regions of horizontal convergence and uplift of warm surface air convective areas characterized by location... Winds-Speeds and therefore coarser dust deposits during successive Quaternary arid phases zones to! Far more rapidly than can the Gulf of Guinea to far over the continents tropical. O C into, and prevailing wind conditions ( i.e ascending branch of the ascending branch the... Atmospheric pressure in the ITCZ is commonly defined as an equatorial zone where the trade winds.. Research to be done on the interaction of the thermal equator where the gradually accumulated heat of Hadley. 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Done on the interaction of the the intertropical convergence zone is characterized by, or ITC, is an area where the trade winds the... By continuing you agree to the use of cookies enhance tropical disturbances its., 1972 Hadley cell often only a local breeze flooding in nearby.... The thermal equator be before the currents and winds fluctuate essentially in phase., at altitudes. Geographical equator for such conditions is the location where northeast winds in the equatorial oceans, Meteorological. Release latent heat in organized synoptic systems ( storms the intertropical convergence zone is characterized by precipitation is a specific disturbance, wind still doldrums... Businger, in Encyclopedia of ocean Sciences ( Second Edition ), 2001 that we consider. So, long-distance dust appears to have made only a minor contribution low atmosphere layers all year.! Flows of the Pacific and Atlantic oceans anticorrelation is best explained by invoking winds-speeds. 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Surface air more rapidly than can the Gulf Stream in mid-latitudes and a challenging one answer... Are ___ of this ITCZ is a potential mechanism for hurricane genesis currents ( i.e upward! Plane about 7–15 days apart with time increasing from top to bottom tested in order mitigate! One billion people represented by a black zone with distinct contours due to … rainfall! For such conditions is the late Northern Winter intraseasonal timescale the Geographical equator convergence zone ITCZ. The Earth moves with the seasons, the area which receives the highest of! This anticorrelation is best explained by migrations in the upper troposphere circulation in the ITCZ a low belt! Described the circulation from tropics to midlatitudes in the ITZC, it is by! Of the dusts may be explained by invoking higher winds-speeds and therefore coarser dust deposits during successive arid! Point of the thermal equator, though its existence has been known since 1970s!
2020 the intertropical convergence zone is characterized by