{"id":80743,"date":"2026-01-03T18:31:59","date_gmt":"2026-01-03T13:01:59","guid":{"rendered":"https:\/\/vajiramandravi.com\/current-affairs\/?p=80743"},"modified":"2026-01-03T18:42:33","modified_gmt":"2026-01-03T13:12:33","slug":"jet-streams","status":"publish","type":"post","link":"https:\/\/vajiramandravi.com\/current-affairs\/jet-streams\/","title":{"rendered":"Jet Streams, Characteristics, Types, Formation, Impact"},"content":{"rendered":"<p><span style=\"font-weight: 400;\">Jet Streams are narrow, fast-moving air currents in the upper atmosphere that influence global weather and climate. They are found at high altitudes, flow mainly from west to east, and follow a wavy path called Rossby waves. Based on location and season, they are classified into Polar, Subtropical, Tropical Easterly, and Polar Night Jets, each affecting rainfall, storms, and monsoon patterns differently.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The detailed article on Jet Streams has been discussed below for a better understanding of the concepts.<\/span><\/p>\n<h2><b>Jet Streams<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">Jet streams are <\/span><b>fast-flowing winds in the upper atmosphere<\/b><span style=\"font-weight: 400;\"> that move mainly from west to east and influence weather patterns across the globe. They form due to the <\/span><b>temperature difference between the equator and the poles<\/b><span style=\"font-weight: 400;\"> and are strongest at high altitudes. Jet streams <\/span><b>guide storms, cyclones, and rainfall<\/b><span style=\"font-weight: 400;\">, and their position shifts with the seasons. Changes in their strength or path can cause <\/span><b>extreme weather events<\/b><span style=\"font-weight: 400;\"> like heatwaves, floods, or cold waves.<\/span><\/p>\n<p><strong>Also Read: <a href=\"https:\/\/vajiramandravi.com\/upsc-exam\/environment\/\" target=\"_blank\">Environment<\/a><\/strong><\/p>\n<h2><b>Jet Streams Characteristics<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">The characteristics of Jet Streams have been shared below.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Jet Streams are found at <\/span><b>high altitudes in the upper troposphere and lower stratosphere<\/b><span style=\"font-weight: 400;\">, mainly between <\/span><b>20\u00b0 latitude and the polar regions<\/b><span style=\"font-weight: 400;\">, at about <\/span><b>9\u201316 km height<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Blow primarily from <\/span><b>west to east (westerlies)<\/b><span style=\"font-weight: 400;\"> due to Earth\u2019s rotation and pressure gradient forces.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Possess <\/span><b>very high wind speeds<\/b><span style=\"font-weight: 400;\">, generally ranging from <\/span><b>150 to over 300 km\/h<\/b><span style=\"font-weight: 400;\">, with maximum speed at the <\/span><b>jet core<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Strength of jet streams increases in <\/span><b>winter<\/b><span style=\"font-weight: 400;\"> because of a greater temperature difference between polar and tropical air.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Follow a <\/span><b>wavy path known as Rossby waves<\/b><span style=\"font-weight: 400;\">, instead of a straight flow, influencing weather systems.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Show <\/span><b>seasonal shifting<\/b><span style=\"font-weight: 400;\">, moving northward in summer and southward in winter, extending closer to the equator during winter.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Form due to a <\/span><b>strong thermal gradient<\/b><span style=\"font-weight: 400;\"> between cold polar air and warm tropical air masses.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Exhibit <\/span><b>strong vertical and horizontal wind shear<\/b><span style=\"font-weight: 400;\">, leading to clear-air turbulence that affects aircraft.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Are <\/span><b>circumpolar in nature<\/b><span style=\"font-weight: 400;\">, encircling the Earth in both hemispheres, though their paths are irregular and dynamic.<\/span><\/li>\n<\/ul>\n<h2><b>Types of Jet Streams<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">Based on their location, altitude, and seasonal behavior, jet streams are broadly classified into permanent (zonal) jet streams and seasonal or temporary jet streams.<\/span><\/p>\n<h3><b>Permanent (Zonal) Jet Streams<\/b><\/h3>\n<ol>\n<li><b> Polar Jet Stream (Polar Front Jet)<\/b><\/li>\n<\/ol>\n<p><span style=\"font-weight: 400;\">The Polar Jet Stream is located in the mid-latitudes, around 45\u00b0\u201360\u00b0, where cold polar air meets warm tropical air. It is strongest during winter, shows large meanders, and is a major driver of mid-latitude weather systems and storms.<\/span><\/p>\n<ol start=\"2\">\n<li><b> Subtropical Jet Stream<\/b><\/li>\n<\/ol>\n<p><span style=\"font-weight: 400;\">The Subtropical Jet Stream occurs near 30\u00b0\u201335\u00b0 latitudes and is generally weaker and more stable than the polar jet. It is often associated with descending air and relatively stable or fair weather conditions in subtropical regions.<\/span><\/p>\n<h3><b>Seasonal and Temporary Jet Streams<\/b><\/h3>\n<ol>\n<li><b> Tropical Easterly Jet (TEJ)<\/b><\/li>\n<\/ol>\n<p><span style=\"font-weight: 400;\">The Tropical Easterly Jet develops during summer over India and Africa due to intense heating of the Tibetan Plateau. It flows from east to west and is crucial for strengthening monsoon circulation and rainfall.<\/span><\/p>\n<ol start=\"2\">\n<li><b> Polar Night Jet<\/b><\/li>\n<\/ol>\n<p><span style=\"font-weight: 400;\">The Polar Night Jet forms in the stratosphere over polar regions during winter because of extreme temperature differences. It is distinct from the polar front jet and mainly influences upper-atmospheric circulation.<\/span><\/p>\n<ol start=\"3\">\n<li><b> Low-Level Jet Streams (e.g., Somali Jet)<\/b><\/li>\n<\/ol>\n<p><span style=\"font-weight: 400;\">Low-level jet streams occur in the lower troposphere, with the Somali Jet being a notable example. It transports large amounts of moisture towards the Indian subcontinent, playing an important role in monsoon rainfall.<\/span><\/p>\n<p><strong>Also Read: <a href=\"https:\/\/vajiramandravi.com\/upsc-exam\/western-disturbances-in-india\/\" target=\"_blank\">Western Disturbances<\/a><\/strong><\/p>\n<h2><b>Formation of Jet Streams<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">Jet streams are formed due to the uneven heating of the Earth\u2019s surface, which creates strong temperature and pressure differences between the equator and the poles. These differences, combined with Earth\u2019s rotation, lead to the development of fast-moving winds in the upper atmosphere.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The equatorial region receives more solar energy than the polar regions, creating a thermal gradient between warm and cold air masses.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Warm air rises and moves poleward in the upper atmosphere, while cold air moves equatorward near the surface.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">This movement of air generates <\/span><b>pressure differences<\/b><span style=\"font-weight: 400;\"> at higher altitudes.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Air flows from high-pressure to low-pressure zones, accelerating in the process.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Due to the <\/span><b>Coriolis force<\/b><span style=\"font-weight: 400;\">, moving air is deflected, resulting in a dominant <\/span><b>west-to-east flow<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Jet streams form near the <\/span><b>tropopause<\/b><span style=\"font-weight: 400;\">, where temperature contrasts are strongest.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">During winter, increased temperature differences make jet streams stronger and faster.<\/span><\/li>\n<\/ul>\n<h2><b>Latitudinal and Seasonal Shifting of Jet Streams<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">Jet Streams do not remain fixed at one location and shift both latitudinally and seasonally in response to changes in solar heating. Their position and strength vary throughout the year, strongly influencing weather and climate patterns.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Jet streams move northward during summer as the Sun\u2019s direct rays shift toward higher latitudes.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">In winter, they shift southward toward the equator due to the expansion of cold polar air.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Winter jet streams are stronger and more extensive because of a sharper temperature contrast between polar and tropical regions.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">During summer, the temperature gradient weakens, causing jet streams to weaken and move poleward.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Seasonal shifting affects the paths of cyclones and storm systems.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Irregular or delayed shifting can lead to extreme weather events such as heatwaves, cold waves, or heavy rainfall.<\/span><\/li>\n<\/ul>\n<h2><b>Jet Streams and Cyclone Formation<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">Jet Streams play a crucial role in the formation, intensification, and movement of cyclones by controlling upper-air circulation. Their position and strength determine how cyclonic systems develop and travel.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Jet streams help in <\/span><b>upper-level divergence<\/b><span style=\"font-weight: 400;\">, which removes air from the top of a developing cyclone and allows surface pressure to fall.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Strong jet streams provide the necessary <\/span><b>energy and ventilation<\/b><span style=\"font-weight: 400;\"> for cyclones to intensify.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Cyclones often move along the <\/span><b>path guided by jet streams<\/b><span style=\"font-weight: 400;\">, which act as steering currents.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">A fast-moving jet stream can cause cyclones to <\/span><b>intensify rapidly and move quickly<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Weak or blocked jet streams may result in <\/span><b>slow-moving cyclones<\/b><span style=\"font-weight: 400;\">, leading to prolonged rainfall and flooding.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Interaction between jet streams and low-pressure systems is essential for the <\/span><b>development of temperate cyclones<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<\/ul>\n<h2><b>Influence of Jet Streams on Indian Monsoon<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">Jet Streams have a decisive influence on the onset, strength, and distribution of monsoon rainfall over the Indian subcontinent. Their seasonal shifting controls the large-scale atmospheric circulation associated with the monsoon.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">During summer, the <\/span><b>Subtropical Westerly Jet Stream shifts north of the Himalayas<\/b><span style=\"font-weight: 400;\">, allowing warm, moist monsoon winds to enter India.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The development of the <\/span><b>Tropical Easterly Jet (TEJ)<\/b><span style=\"font-weight: 400;\"> over India strengthens upper-level divergence and supports active monsoon conditions.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">A strong TEJ is associated with <\/span><b>good and widespread monsoon rainfall<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">If the westerly jet fails to shift northward, it can <\/span><b>delay the onset of the monsoon<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<\/ul>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Variations in jet stream position and strength may cause <\/span><b>breaks in monsoon rainfall or regional droughts<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<\/ul>\n<h2><b>Impact of Jet Streams on Aviation<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">Jet Streams play an important role in aviation by affecting flight speed, fuel use, and safety. Aircraft flying in the direction of jet streams can save time and fuel, while flying against them increases travel time. Strong jet streams often cause clear-air turbulence, which can be dangerous as it is hard to detect. Therefore, pilots carefully plan flight routes using jet stream forecasts to ensure safe and efficient air travel.<\/span><\/p>\n<h2><b>Changes in Jet Streams due to Global Warming<\/b><\/h2>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Global warming is causing <\/span><b>faster warming of polar regions<\/b><span style=\"font-weight: 400;\"> compared to the tropics, a phenomenon known as <\/span><b>polar amplification<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">This reduces the <\/span><b>temperature (thermal) gradient<\/b><span style=\"font-weight: 400;\"> between the equator and the poles, which is the main driving force of jet streams.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">A weaker thermal gradient leads to <\/span><b>weaker jet streams<\/b><span style=\"font-weight: 400;\"> with reduced wind speeds.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Jet streams are becoming <\/span><b>more wavy and irregular<\/b><span style=\"font-weight: 400;\">, showing larger Rossby wave amplitudes.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Increased waviness causes <\/span><b>weather systems to move slowly or remain stationary<\/b><span style=\"font-weight: 400;\"> over a region.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">This results in <\/span><b>prolonged extreme weather events<\/b><span style=\"font-weight: 400;\"> such as heatwaves, cold spells, floods, and droughts.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Weaker and unstable jet streams can lead to <\/span><b>frequent blocking patterns<\/b><span style=\"font-weight: 400;\">, disrupting normal weather flow.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Changes in jet stream behavior are affecting <\/span><b>monsoon patterns and mid-latitude storm tracks<\/b><span style=\"font-weight: 400;\">.<\/span><\/li>\n<\/ul>\n<h2><b>Jet Streams UPSC Prelims PYQs<\/b><\/h2>\n<ol>\n<li><span style=\"font-weight: 400;\"> Consider the following statements: (2020, UPSC CSE Prelims)<\/span><\/li>\n<\/ol>\n<ol>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Jet streams occur in the Northern Hemisphere only.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Only some cyclones develop an eye.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The temperature inside the eye of a cyclone is nearly 10\u00b0C lesser than that of the surroundings.<\/span><\/li>\n<\/ol>\n<p><span style=\"font-weight: 400;\">Which of the statements given above is\/are correct?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">(a) 1 and 2 only<\/span><\/p>\n<p><span style=\"font-weight: 400;\">(b) 2 and 3 only<\/span><\/p>\n<p><span style=\"font-weight: 400;\">(c) 3 only<\/span><\/p>\n<p><span style=\"font-weight: 400;\">(d) 1, 2 and 3<\/span><\/p>\n<p><b>Answer: (b)<\/b><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Know about jet streams, their types, characteristics, formation, seasonal shifts, and how they affect weather, cyclones, monsoon, aviation, and climate.<\/p>\n","protected":false},"author":27,"featured_media":80862,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[786],"tags":[4548],"class_list":{"0":"post-80743","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-general-studies","8":"tag-jet-streams","9":"no-featured-image-padding"},"acf":[],"_links":{"self":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/80743","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/users\/27"}],"replies":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/comments?post=80743"}],"version-history":[{"count":0,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/80743\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media\/80862"}],"wp:attachment":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media?parent=80743"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/categories?post=80743"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/tags?post=80743"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}