Climate of India 797653 225498079 2008-07-14T00:35:04Z Rjwilmsi 203434 no 'of' between a month and a year per [[Wikipedia:Manual_of_Style_%28dates_and_numbers%29#Longer_periods|MOS]] using [[Project:AutoWikiBrowser|AWB]] [[Image:Agasthiyamalai range and Tirunelveli rainshadow.jpg|thumb|right|A semi-[[arid]] wasteland near [[Tirunelveli]], [[Tamil Nadu]]. Monsoon clouds dump torrents of rain on lush forests that are only kilometres away in [[windward and leeward|windward]]-facing [[Kerala]], but are [[rain shadow|prevented]] from reaching Tirunelveli by the [[Agastya Malai|Agasthyamalai Range]] of the Western Ghats (background).]] [[Image:Valley of flowers uttaranchal full view.JPG|thumb|right|A scene in [[Uttarakhand]]'s [[Valley of Flowers National Park]]. In contrast to Tirunelveli, the park receives ample [[orographic lift|orographic precipitation]] due to its location in a mountainous [[windward and leeward|windward]]-facing region wedged between the [[Zanskar Range|Zanskars]] and the [[Great Himalayas|Greater Himalayas]].]] The '''climate of India''' defies easy generalisation, comprising a wide range of weather conditions across a large geographic scale and varied topography. Analysed according to the [[Köppen climate classification|Köppen system]], [[India]] hosts six major climatic subtypes, ranging from [[desert]] in the west, to [[alpine tundra]] and [[glacier]]s in the north, to humid tropical regions supporting [[rainforest]]s in the southwest and the island territories. Many regions have starkly different [[microclimate]]s. The nation has four seasons: winter (January and February), summer (March to May), a [[monsoon]] (rainy) season (June to September), and a post-monsoon period (October to December). India's unique [[geography of India|geography]] and [[geology of India|geology]] strongly influence its climate; this is particularly true of the [[Himalayas]] in the north and the [[Thar Desert]] in the northwest. The Himalayas act as a barrier to the frigid [[katabatic wind]]s flowing down from [[Central Asia]]. Thus, [[North India]] is kept warm or only mildly cold during winter; in summer, the same phenomenon makes India relatively hot. Although the [[Tropic of Cancer]]—the boundary between the tropics and subtropics—passes through the middle of India, the whole country is considered to be tropical. As in much of the tropics, monsoonal and other weather conditions in India are unstable: major droughts, floods, cyclones and other natural disasters are sporadic, but have killed or displaced millions. India's long-term climatic stability is further threatened by [[global warming]]. Climatic diversity in India makes the analysis of these issues complex. == History == [[Image:India-view of shilla.jpg|thumb|right|The formation of the Himalayas (pictured) during the [[Ypresian|Early Eocene]] some 53 million years ago was a key factor in determining India's modern-day climate; global climate and ocean chemistry may have been impacted.<ref>{{cite journal |author=Rowley DB |year=1996 |url=http://www.gps.caltech.edu/~avouac/GE277/Rowley96.pdf |archiveurl=http://web.archive.org/web/20070417165546/http://www.gps.caltech.edu/~avouac/GE277/Rowley96.pdf |archivedate=2007-04-17 |format=PDF|title=Age of initiation of collision between India and Asia: A review of stratigraphic data |journal=Earth and Planetary Science Letters |volume=145 |issue=1 |pages=1–13 |accessdate=2007-03-31|doi=10.1016/S0012-821X(96)00201-4}}</ref>]] During the [[Lopingian|Late Permian]] (some 260–251&nbsp;[[mya (unit)|million years ago]]), the [[Indian subcontinent]] was part of the vast [[supercontinent]] [[Pangaea]]. Despite its position within a high-latitude belt at 55–75°&nbsp;S (as opposed to its current position between 5 and 35°&nbsp;N), latitudes now occupied by such places as [[Greenland]] and parts of the [[Antarctic Peninsula]], India likely experienced a humid temperate climate with warm, frost-free weather, though with well-defined seasons.<ref>{{cite journal |author=Chumakov NM, Zharkov MA |year=2003 |url=http://palaeoentomolog.ru/Lib/Chumakov3.pdf |format=PDF |title=Climate of the Late Permian and Early Triassic: General Inferences |journal=Stratigraphy and Geological Correlation |volume=11 |issue=4 |pages=361–375 |accessdate=2007-03-26}}</ref> Later, India joined the southern supercontinent [[Gondwana]], a process beginning some 550–500&nbsp;mya. During the Late [[Paleozoic]], Gondwana extended from a point at or near the [[South Pole]] to near the equator, where the [[Indian craton]] (stable [[continental crust]]) was positioned, resulting in a mild climate favourable to hosting high-[[biomass]] [[ecosystems]]. This is underscored by India's vast coal reserves—much of it from the late Paleozoic sedimentary sequence—the fourth-largest reserves in the world.<ref name=coalreservecia>{{cite web | url = https://www.cia.gov/library/publications/the-world-factbook/geos/in.html | title = India | accessdate = 2007-04-19 | date = [[17 April]] 2007 | work = The World Fact Book | publisher = Central Intelligence Agency }}</ref> During the [[Mesozoic]], the world, including India, was considerably warmer than today. With the coming of the [[Carboniferous]], [[global cooling]] stoked extensive [[glaciation]], which spread northwards from [[South Africa]] towards India; this cool period lasted well into the [[Permian]].<ref>{{cite journal |author=Grossman EL, Bruckschen P, Mii H, Chuvashov BI, Yancey TE, Veizer J |year=2002 |url=http://geoweb.tamu.edu/faculty/grossman/Grossman02.pdf |format=PDF|title=Climate of the Late Permian and Early Triassic: General Inferences |journal=Carboniferous Stratigraphy and Paleogeography in Eurasia |pages=61–71 |accessdate=2007-04-05}}</ref> [[Plate tectonics|Tectonic movement]] by the [[Indian Plate]] caused it to pass over a geologic [[hotspot (geology)|hotspot]]—the [[Réunion hotspot]]—now occupied by the volcanic island of [[Réunion]]. This resulted in a massive [[flood basalt]] event that laid down the [[Deccan Traps]] some 60–68&nbsp;mya,<ref name="mantleplumes">{{cite web |author=Sheth HC |url=http://www.mantleplumes.org/Deccan.html |title=Deccan Traps: The Deccan beyond the plume hypothesis |date=[[29 August]] [[2006]] |accessdate=2007-04-01}}</ref><ref>{{cite journal |author=Iwata N |title=Geochronological study of the Deccan volcanism by the <sup>40</sup>Ar-<sup>39</sup>Ar method |url=http://www.blackwell-synergy.com/doi/abs/10.1046/j.1440-1738.2001.00290.x |journal=University of Tokyo (Ph.D. thesis) |year=1997 |accessdate=2007-04-01 |doi=10.1046/j.1440-1738.2001.00290.x |volume=10 |pages=22}}</ref> at the end of the [[Cretaceous]] period. This may have contributed to the global [[Cretaceous-Tertiary extinction event|Cretaceous-Tertiary (K-T) extinction event]], which caused India to experience significantly reduced [[insolation]]. Elevated atmospheric levels of sulphur gases formed [[aerosol]]s such as [[sulfur dioxide]] and [[sulfuric acid]], similar to those found in the [[atmosphere of Venus]]; these precipitated as [[acid rain]]. Elevated [[carbon dioxide]] emissions also contributed to the [[greenhouse effect]], causing [[climate change|warmer weather]] that lasted long after the atmospheric shroud of dust and aerosols had cleared. Further climatic changes 20 million years ago, long after India had crashed into the [[Laurasia]]n landmass, were severe enough to cause the extinction of many endemic Indian forms.<ref>{{cite journal |author=Karanth KP |year=2006 |month=March |url=http://www.iisc.ernet.in/currsci/mar252006/789.pdf |format=PDF|title=Out-of-India Gondwanan origin of some tropical Asian biota |journal=Current Science |volume=90 |issue=6 |pages=789–792 |accessdate=2007-04-08}}</ref> The formation of the Himalayas resulted in blockage of frigid Central Asian air, preventing it from reaching India; this made its climate significantly warmer and more tropical in character than it would otherwise have been.<ref name="Wolpert_2000_4">{{harvnb|Wolpert|2000|p=4}}.</ref><!--<ref>{{cite paper |title=Water Resources of India: Physiographic Conditions |publisher=Ministry of Water Resources (Government of India) }}</ref>--> == Regions == {{main|Climatic regions of India}} {| align="right" |- | style="vertical-align:top;" | [[Image:India average annual temperature map en.svg|thumb|right|Average annual temperatures across India:{{crlf}}{{crlf}} {| cellspacing="0" align="center" style="background:#F9F9F9; font-size:100%; width:100%; %border:1px #000000;" |- | {{legend|#C6A0F3|Below 20.0&nbsp;°C}} || (< 68.0{{spaces|1}}°F) |- | {{legend|#80B3F3|20.0–22.5&nbsp;°C}} || (68.0–72.5{{spaces|1}}°F) |- | {{legend|#CDDE7B|22.5–25.0&nbsp;°C}} || (72.5–77.0{{spaces|1}}°F) |- | {{legend|#FFF2B3|25.0–27.5&nbsp;°C}} || (77.0–81.5{{spaces|1}}°F) |- | {{legend|#DE877B|Above 27.5&nbsp;°C}} || (> 81.5{{spaces|1}}°F) | |} ]] | style="vertical-align:top;" | [[Image:India climatic zone map en.svg|thumb|right|Climatic zones in India, based on the [[Köppen climate classification|Köppen classification system]]:{{crlf}}{{crlf}} {| cellspacing="0" align="center" style="background:#F9F9F9; font-size:100%; width:100%; %border:1px #000000;" |- | {{legend|#C6A0F3|[[Alpine climate|Alpine]]}} || '''E''' || ''(ETh)'' |- | {{legend|#A0C6F3|[[Humid subtropical climate|Humid subtropical]]}} || '''C''' || ''(Cfa)'' |- | {{legend|#D4EFB7|[[Tropical climate|Tropical wet and dry]]}} || '''A''' || ''(Aw)'' |- | {{legend|#739A4D|[[Tropical climate|Tropical wet]]}} || '''A''' || ''(Am)'' |- | {{legend|#FFE674|[[Semi-arid]]}} || '''B''' || ''(BSh)'' |- | {{legend|#DE877B|[[Arid]]}} || '''B''' || ''(BWh)'' | |} ]] |} India is home to an extraordinary variety of climatic regions, ranging from tropical in the south to temperate and alpine in the Himalayan north, where elevated regions receive sustained winter snowfall. The nation's climate is strongly influenced by the Himalayas and the Thar Desert.<ref name="Chang_1967">{{cite journal |author=Chang, JH |year=1967 |title=The Indian Summer Monsoon |journal=Geographical Review |volume=57 |issue=3 |pages=373–396 |doi=10.2307/212640}}</ref> The Himalayas, along with the [[Hindu Kush]] mountains in [[Pakistan]], prevent cold Central Asian katabatic winds from blowing in, keeping the bulk of the Indian subcontinent warmer than most locations at similar [[latitude]]s.<ref name="Posey_1994_118">{{harvnb|Posey|1994|p=118}}.</ref> Simultaneously, the Thar Desert plays a role in attracting moisture-laden southwest summer monsoon winds that, between June and October, provide the majority of India's rainfall.<ref name="Chang_1967"/><ref name="NCERT_28">{{cite web |url=http://www.ncert.nic.in/book_publishing/Class%209/Geography/Chapter%204.pdf |format=PDF|title=Climate |work=National Council of Educational Research and Training (NCERT). |pages=p. 28 |accessdate=2007-03-31}}</ref> Four major climatic groupings predominate, into which fall seven climatic zones that, as designated by experts, are defined on the basis of such traits as temperature and precipitation.<ref name="Heitzman_Worden_1996_97">{{harvnb|Heitzman|Worden|1996|p=97}}.</ref> Groupings are assigned codes (see chart) according to the Köppen climate classification system. === Tropical wet === A tropical rainy climate covers regions experiencing persistent warm or high temperatures, which normally do not fall below {{convert|18|°C|°F|0|lk=on}}. India hosts two climatic subtypes that fall under this group. The most humid is the tropical wet monsoon climate that covers a strip of southwestern lowlands abutting the [[Malabar Coast]], the [[Western Ghats]], and southern [[Assam]]. India's two island territories, [[Lakshadweep]] and the [[Andaman and Nicobar Islands]], are also subject to this climate. Characterised by moderate to high year-round temperatures, even in the foothills, its rainfall is seasonal but heavy—typically above {{convert|2000|mm|in|0}} per year.<ref name="Chouhan_1992_7">{{harvnb|Chouhan|1992|p=7}}.</ref> Most rainfall occurs between May and November; this is adequate for the maintenance of lush forests and other vegetation throughout the remainder of the year. December to March are the driest months, when days with precipitation are rare. The heavy monsoon rains are responsible for the extremely biodiverse tropical wet forests of these regions. In India, a tropical wet and dry climate is more common. Significantly drier than tropical wet zones, it prevails over most of inland peninsular India except for a semi-[[arid]] rain shadow east of the Western Ghats. Winter and early summer are long, dry periods with temperatures averaging above {{convert|18|°C|°F|0}}. Summer is exceptionally hot; temperatures in low-lying areas may exceed {{convert|50|°C|°F|0}} during May, leading to heat waves that can each kill hundreds of Indians.<ref name="Farooq_2002"/> The rainy season lasts from June to September; annual rainfall averages between 750–1500&nbsp;millimetres (30–59&nbsp;in) across the region. Once the dry northeast monsoon begins in September, most precipitation in India falls on Tamil Nadu, leaving other states comparatively dry.<ref name="Healy">{{cite web |author=Healy M |title=South Asia: Monsoons |publisher=Harper College |url=http://www.harpercollege.edu/mhealy/g101ilec/sasia/ssd/ssmon/ssmonfr.htm |accessdate=2007-04-08}}</ref> === Tropical dry === A tropical [[arid]] and semi-[[arid]] climate dominates regions where the rate of moisture loss through [[evapotranspiration]] exceeds that from precipitation; it is subdivided into three climatic subtypes. The first, a tropical semi-[[arid]] steppe climate, predominates over a long stretch of land south of Tropic of Cancer and east of the Western Ghats and the [[Cardamom Hills]]. The region, which includes [[Karnataka]], inland Tamil Nadu, western [[Andhra Pradesh]], and central [[Maharashtra]], gets between 400–750&nbsp;millimetres (16–30&nbsp;in) annually. It is drought-prone, as it tends to have less reliable rainfall due to sporadic lateness or failure of the southwest monsoon.<ref name="Caviedes_2001_124">{{harvnb|Caviedes|2001|p=124}}</ref> North of the [[Krishna River]], the summer monsoon is responsible for most rainfall; to the south, significant post-monsoon rainfall also occurs in October and November. In December, the coldest month, temperatures still average around 20–24 °C (68–75&nbsp;°F). The months between March to May are hot and dry; mean monthly temperatures hover around 32 °C, with {{convert|320|mm|in|0}} precipitation. Hence, without artificial irrigation, this region is not suitable for permanent agriculture. [[Image:Great rann of kutch.JPG|thumb|The [[Rann of Kutch]], a vast [[salt marsh]] south of the Thar Desert in [[Gujarat]]. During the monsoon season, the region fills with standing waters.]] <!--[[Image:Jaisalmer-3.jpg|thumb|left|[[Jaisalmer]], in western Rajasthan, is situated in the heart of the Thar Desert. The region is [[arid]] and dusty.]]--> Most of western [[Rajasthan]] experiences an [[arid]] climatic regime. [[Cloudburst]]s are responsible for virtually all of the region's annual precipitation, which totals less than {{convert|300|mm|in|0}}. Such bursts happen when monsoon winds sweep into the region during July, August, and September. Such rainfall is highly erratic; regions experiencing rainfall one year may not see precipitation for the next couple of years or so. Atmospheric moisture is largely prevented from precipitating due to continuous [[vertical draft|downdrafts]] and other factors.<ref>{{cite journal |author=Singhvi AK, Kar A |url=http://www.ias.ac.in/jess/sep2004/eps-singh.pdf |format=PDF|title=The aeolian sedimentation record of the Thar Desert |journal=Proc Indian Acad Sci (Earth Planet Sci) |year=2004 |month=September |volume=113 |issue=3 |pages=371–401 |accessdate=2007-04-08}}</ref> The summer months of May and June are exceptionally hot; mean monthly temperatures in the region hover around {{convert|35|°C|°F|0}}, with daily maxima occasionally topping {{convert|50|°C|°F|0}}. During winters, temperatures in some areas can drop below freezing due to waves of cold air from Central Asia. There is a large diurnal range of about {{convert|14|°C|°F|0}} during summer; this widens by several degrees during winter. East of the Thar Desert, the region running from [[Punjab, India|Punjab]] and [[Haryana]] to [[Kathiawar]] experiences a tropical and sub-tropical [[steppe]] climate. The zone, a transitional climatic region separating tropical desert from humid sub-tropical savanna and forests, experiences temperatures that are less extreme than those of the desert. Average annual rainfall is 30–65&nbsp;centimetres (12-26&nbsp;in), but is very unreliable; as in much of the rest of India, the southwest monsoon accounts for most precipitation. Daily summer temperature maxima rise to around {{convert|40|°C|°F|0}}. The resulting natural vegetation typically comprises short, coarse grasses. === Subtropical humid === Most of Northeast India and much of North India are subject to a humid sub-tropical climate. Though they experience hot summers, temperatures during the coldest months may fall as low as {{convert|0|°C|°F|0}}. Due to ample monsoon rains, India has only one subtype of this climate, ''Cfa'' (under the Köppen system).<ref>{{cite web |url=http://www.utexas.edu/depts/grg/kimmel/GRG301K/grg301kkoppen.html|author=Kimmel TM |title=Weather and climate: Koppen climate classification flow chart |publisher=University of Texas at Austin |year=2000 |accessdate=2007-04-08}}</ref> In most of this region, there is very little precipitation during the winter, owing to powerful anticyclonic and katabatic (downward-flowing) winds from Central Asia. Due to the region's proximity to the Himalayas, it experiences elevated prevailing wind speeds, again from the influence of Central Asian katabatic movements. Humid subtropical regions are subject to pronounced dry winters. Winter rainfall—and occasionally snowfall—is associated with large storm systems such as "Nor'westers" and "[[Western disturbances]]"; the latter are steered by [[westerlies]] towards the Himalayas.<ref name="Das_2002"/> Most summer rainfall occurs during powerful thunderstorms associated with the southwest summer monsoon; occasional [[tropical cyclones]] also contribute. Annual rainfall ranges from less than {{convert|1000|mm|in|0}} in the west to over {{convert|2500|mm|in|0}} in parts of the northeast. As most of this region is far from the ocean, the wide temperature swings more characteristic of a [[continental climate]] predominate; the swings are wider than in those in tropical wet regions, ranging from {{convert|24|°C|°F|0}} in north-central India to {{convert|27|°C|°F|0}} in the east. === Montane === [[Image:Pangong Tso lake.jpg|thumb|right|[[Pangong Tso|Pangong Lake]] in [[Ladakh]], an [[arid]] montane region lying deep within the Himalayas.]] India's northernmost fringes are subject to a montane, or alpine, climate. In the Himalayas, the rate at which an air mass's temperature falls per kilometre (3,281&nbsp;ft) of altitude gained (the [[lapse rate|adiabatic lapse rate]]) is 5.1&nbsp;°C/km.<ref>{{cite journal |author=Carpenter C |year=2005 |title=The environmental control of plant species density on a Himalayan elevation gradient |journal=Journal of Biogeography |volume=32 |issue=6 |pages=999–1018 |doi=10.1111/j.1365-2699.2005.01249.x}}</ref> In terms of [[environmental lapse rate]], ambient temperatures fall by 0.6&nbsp;°C (1.1&nbsp;°F) for every {{convert|100|m|ft|0}} rise in altitude. Thus, climates ranging from nearly tropical in the foothills to tundra above the [[snow line]] can coexist within several dozen miles of each other. Sharp temperature contrasts between sunny and shady slopes, high diurnal temperature variability, temperature inversions, and altitude-dependent variability in rainfall are also common. The northern side of the western Himalayas, also known as the trans-Himalayan belt, is a region of barren, [[arid]], frigid, and wind-blown wastelands. Most precipitation occurs as snowfall during the late winter and spring months. Areas south of the Himalayas are largely protected from cold winter winds coming in from the Asian interior. The leeward side (northern face) of the mountains receives less rain while the southern slopes, well-exposed to the monsoon, get heavy rainfall. Areas situated at elevations of 1,070–2,290 metres (3,510–7,510&nbsp;ft) receive the heaviest rainfall, which decreases rapidly at elevations above {{convert|2290|m|ft|0}}. The Himalayas experience their heaviest snowfall between December and February and at elevations above {{convert|1500|m|ft|0}}. Snowfall increases with elevation by up to several dozen millimetres per 100&nbsp;metre (~2&nbsp;in; 330&nbsp;ft) increase. Elevations above {{convert|5000|m|ft|0}} never experience rain; all precipitation falls as snow.<ref>{{cite journal |author=Singh P, Kumar N |year=1997 |title=Effect of orography on precipitation in the western Himalayan region |journal=Journal of Hydrology |volume=199 |issue=1 |pages=183–206 |doi=10.1016/S0022-1694(96)03222-2}}</ref> == Seasons == <!--[[Image:India Goa Fort Chapora Chapora River.jpg|thumb|Clear skies prevail during the post-monsoon and winter seasons in most parts of India, including the coastal state of [[Goa]].]]--> The [[India Meteorological Department]] (IMD) designates four official seasons:<ref name="IMD_four_seasons"/> [[Image:Fort Bandhavgarh National Park Madhya Pradesh India.jpg|thumb|right|A winter scene in [[Bandhavgarh National Park]], [[Madhya Pradesh]].]] * '''Winter''', occurring between January and March. The year's coldest months are December and January, when temperatures average around 10–15&nbsp;°C (50–59&nbsp;°F) in the northwest; temperatures rise as one proceeds towards the equator, peaking around 20–25&nbsp;°C (68–77&nbsp;°F) in mainland India's southeast. * '''Summer''' or '''pre-monsoon''' season, lasting from March to June (April to July in northwestern India). In western and southern regions, the hottest month is April; for northern regions, May is the hottest month. Temperatures average around 32–40&nbsp;°C (90–104&nbsp;°F) in most of the interior. * '''Monsoon''' or '''rainy''' season, lasting from June to September. The season is dominated by the humid southwest summer monsoon, which slowly sweeps across the country beginning in late May or early June. Monsoon rains begin to recede from North India at the beginning of October. * '''Post-monsoon''' season, lasting from October to December. South India typically receives more precipitation. Monsoon rains begin to recede from North India at the beginning of October. In northwestern India, October and November are usually cloudless. Parts of the country experience the dry northeast monsoon. The Himalayan states, being more temperate, experience an additional two seasons: autumn and spring. Traditionally, Indians note six seasons, each about two months long. These are the spring (''{{lang-sa|vasanta}}''), summer (''grīṣma''), monsoon season (''varṣā''), early autumn (''śarada''), late autumn (''hemanta''), and winter (''śiśira''). These are based on the astronomical division of the twelve months into six parts. The ancient [[Hindu calendar]] also reflects these seasons in its arrangement of months. === Winter === <!--[[Image:Gurudongmar north sikkim himalayas india.jpg|thumb|right|[[Gurudogmar Lake]] in winter, elevation {{convert|5148|m|ft|0}}, in [[North Sikkim]].]]--> <!--[[Image:Rathong from Zemathang2.jpg|thumb|right|The Indian Himalayas regularly experience heavy snowfall and other inclement conditions. Pictured is Goecha Peak in [[West Sikkim]].]]--> <!--[[Image:Vaishno.jpg|thumb|right|Inclement conditions abound in Indian Himalayas: pictured is the [[Vaishno Devi]] temple in [[Jammu]], shrouded in snow.]]--> Once the monsoons subside, average temperatures gradually fall across India. As the Sun's vertical rays move south of the equator, most of the country experiences moderately cool weather; temperatures change by about 0.6&nbsp;°C (1.35&nbsp;°F) per degree of latitude. December and January are the coldest months, with mean temperatures of 10–15&nbsp;°C (50–59&nbsp;°F) in Indian Himalayas. Mean temperatures are higher in the east and south, where they reach 20–25&nbsp;°C (68–77&nbsp;°F). In northwestern India, virtually cloudless conditions prevail in October and November, resulting in wide diurnal temperature swings; as in much of the Deccan Plateau, they range between 16–20&nbsp;°C (61–68&nbsp;°F). However, from March to May, "western disturbances" bring heavy bursts of rain and snow. These extra-tropical [[low pressure area|low-pressure system]]s originate in the eastern [[Mediterranean Sea]].<ref name="Hatwar_2005">{{cite journal |author=Hatwar HR, Yadav BP, Rama Rao YV |title=Prediction of western disturbances and associated weather over Western Himalayas |journal=Current Science |volume=88 |issue=6 |pages=913–920 |year=2005 |month=March |url=http://www.ias.ac.in/currsci/mar252005/913.pdf |format=PDF |accessdate=2007-03-23}}</ref> They are carried towards India by the subtropical [[westerlies]], which are the [[prevailing winds]] blowing at North India's range of latitude.<ref name="Das_2002">{{cite journal |author=Das MR, Mukhopadhyay RK, Dandekar MM, Kshirsagar SR |title=Pre-monsoon western disturbances in relation to monsoon rainfall, its advancement over NW India and their trends |journal=Current Science |volume=82 |issue=11 |pages=1320–1321 |year=2002 |month=June |url=http://www.ias.ac.in/currsci/jun102002/1320.pdf| format=PDF|accessdate=2007-03-23}}</ref> Once their passage is hindered by the Himalayas, they are unable to proceed further, and they release significant precipitation over the southern Himalayas.<ref>{{cite web |author=Hara M, Kimura F, Yasunari T |title=The Generation Mechanism of the Western Disturbances over the Himalayas |work=Hydrospheric Atmospheric Research Center, Nagoya University |url=http://www.hyarc.nagoya-u.ac.jp/game/6thconf/html/abs_html/pdfs/T4HM09Aug04145134.pdf |format=PDF|accessdate=2007-04-06}}</ref> The three Himalayan states (Jammu and Kashmir in the extreme north, [[Himachal Pradesh]], and [[Uttarakhand]]) experience heavy [[snowfall]]; in Jammu and Kashmir, [[blizzard]]s occur regularly, disrupting travel and other activities. [[Image:Nainital snow lake.jpg|thumb|right|A winter scene by a lake in [[Nainital]], [[Uttarakhand]].]] The rest of [[North India]], including the [[Indo-Gangetic Plain]], almost never receives snow. However, in the plains, temperatures occasionally fall below freezing, though never for more one or two days. Winter highs in Delhi range from {{convert|16|°C|°F|0}} to {{convert|21|°C|°F|0}}. Nighttime temperatures average 2–8&nbsp;°C (36–46&nbsp;°F). In the [[Punjab (India)|Punjab]] plains, lows can fall below freezing, dropping to around {{convert|-6|°C|°F|0}} in [[Amritsar]]. Frost sometimes occurs, but the hallmark of the season is the notorious [[fog]], which frequently disrupts daily life; fog grows thick enough to hinder visibility and disrupt air travel 15–20&nbsp;days annually.<ref name="AI_2003">{{cite web |url=http://www.airindia.com/article.asp?articleid=235 |title=Air India reschedules Delhi-London/New York and Frankfurt flights due to fog |accessdate=2007-03-18 |work=Air India |date=[[17 December]] [[2003]]}}</ref> Eastern India's climate is much milder, experiencing moderately warm days and cool nights. Highs range from {{convert|23|°C|°F|0}} in [[Patna]] to {{convert|26|°C|°F|0}} in [[Kolkata]] (Calcutta); lows average from {{convert|8|°C|°F|0}} in Patna to {{convert|14|°C|°F|0}} in Kolkata. Frigid winds from the Himalayas can depress temperatures near the [[Brahmaputra River]].<ref name="Singh_Ojha_Sharma_2004_168">{{harvnb|Singh|Ojha|Sharma|2004|p=168}}</ref> The two Himalayan states in the east, [[Sikkim]] and [[Arunachal Pradesh]], receive substantial snowfall. The extreme north of [[West Bengal]], centred around [[Darjeeling]], also experiences snowfall, but only rarely. In [[South India]], particularly the hinterland of Maharashtra, [[Madhya Pradesh]], parts of Karnataka, and Andhra Pradesh, somewhat cooler weather prevails. Minimum temperatures in western Maharashtra, Madhya Pradesh and [[Chhattisgarh]] hover around {{C to F|10|precision=0}}; in the southern Deccan Plateau, they reach {{C to F|16|precision=0}}. Coastal areas, especially those near the [[Coromandel Coast]], and low-elevation interior tracts are warm, with daily high temperatures of {{C to F|30|precision=0}} and lows of around {{C to F|21|precision=0}}. The Western Ghats, including the [[Nilgiris (mountains)|Nilgiri Range]], are exceptional; there, lows can fall below freezing.<ref>{{cite journal |author=Blasco F, Bellan MF, Aizpuru M |title=A Vegetation Map of Tropical Continental Asia at Scale 1:5 Million |journal=Journal of Vegetation Science |volume=7 |issue=5 |pages=623–634 |year=1996 |month=October |doi=10.2307/3236374}}</ref> This compares with a range of 12–14&nbsp;°C (54–57&nbsp;°F) on the Malabar Coast; there, as is the case for other coastal areas, the Indian Ocean exerts a strong moderating influence on weather.<ref name="Posey_1994_118">{{harvnb|Posey|1994|p=118}}.</ref> === Summer === [[Image:Khajjiar himachal pradesh india summer.jpg|thumb|right|A summer view of [[Khajjiar]], a hill station in [[Himachal Pradesh]].]] Summer in northwestern India lasts from April to July, and in the rest of the country from March to June. The temperatures in the north rise as the vertical rays of the Sun reach the Tropic of Cancer. The hottest month for the western and southern regions of the country is April; for most of North India, it is May. Temperatures of {{convert|50|°C|°F|0}} and higher have been recorded in parts of India during this season.<ref name="Farooq_2002">{{cite news |author=Farooq O |title=India's heat wave tragedy |work=BBC News |url=http://news.bbc.co.uk/2/hi/south_asia/1994174.stm |date=[[17 May]] [[2002]] |accessdate=2007-04-06}}</ref> In cooler regions of North India, immense pre-monsoon [[squall]]-line thunderstorms, known locally as "Nor'westers", commonly drop large hailstones.<ref>{{cite journal |author=Changnon SA |year=1971 |url=http://ams.allenpress.com/perlserv/?request=get-document&doi=10.1175%2F1520-0450(1971)010%3C0169%3ANOHSD%3E2.0.CO%3B2 |title=Note on hailstone size distributions |journal=Journal of Applied Meteorology |volume=10 |issue=1 |pages=168–170 |accessdate=2007-04-06 |doi=10.1175/1520-0450(1971)010<0169:NOHSD>2.0.CO;2}}</ref> Near the coast the temperature hovers around {{convert|36|°C|°F|0}}, and the proximity of the sea increases the level of humidity. In southern India, the temperatures are higher on the east coast by a few degrees compared to the west coast. By May, most of the Indian interior experiences mean temperatures over {{convert|32|°C|°F|0}}, while maximum temperatures often exceed {{convert|40|°C|°F|0}}. In the hot months of April and May, western disturbances, with their cooling influence, may still arrive, but rapidly diminish in frequency as summer progresses.<ref>{{cite journal |author=Pisharoty PR, Desai BN |title=Western disturbances and Indian weather |journal=Indian Journal of Meteorological Geophysics |year=1956 |volume=7 |pages=333–338}}</ref> Notably, a higher frequency of such disturbances in April correlates with a delayed monsoon onset (thus extending summer) in northwest India. In eastern India, monsoon onset dates have been steadily advancing over the past several decades, resulting in shorter summers there.<ref name="Das_2002"/> Altitude affects the temperature to a large extent, with higher parts of the [[Deccan Plateau]] and other areas being relatively cooler. [[Hill station]]s, such as [[Ootacamund]] ("Ooty") in the Western Ghats and [[Kalimpong]] in the eastern Himalayas, with average maximum temperatures of around {{convert|25|°C|°F|0}}, offer some respite from the heat. At lower elevations, in parts of northern and western India, a strong, hot, and dry wind known as the [[Loo (wind)|Loo]] blows in from the west during the daytime; with very high temperatures, in some cases up to around {{convert|45|°C|°F|0}}; it can cause fatal cases of [[Hyperthermia|sunstroke]]. [[Tornado]]es may also occur, concentrated in a corridor stretching from northeastern India towards Pakistan. They are rare, however; only several dozen have been reported since 1835.<ref name="Peterson_1981">{{cite journal |author=Peterson RE, Mehta KC |title=Climatology of tornadoes of India and Bangladesh |journal=Meteorology and Atmospheric Physics |volume=29 |issue=4 |pages=345–356 |year=1981 |month=December}}</ref> === Monsoon === {| align="right" |- | style="vertical-align:top;" | [[Image:India southwest summer monsoon onset map en.svg|thumb|right|Onset dates and prevailing wind currents of the southwest summer and northeast winter monsoons.]] | style="vertical-align:top;" | [[Image:India annual rainfall map en.svg|thumb|right|Regional variation in rainfall across India. The monsoon season delivers four-fifths of the country's precipitation.]] |} The southwest summer monsoon, a four-month period when massive convective thunderstorms dominate India's weather, is Earth's most productive wet season.<ref name="Collier_Webb_2002_91">{{harvnb|Collier|Webb|2002|p=91}}.</ref> A product of southeast [[trade wind]]s originating from a high-pressure mass centered over the southern Indian Ocean, the monsoonal torrents supply over 80% of India's annual rainfall.<ref name="Bagla">{{cite journal |author=Bagla P |year=2006 |month=August |title=Controversial rivers project aims to turn India's fierce monsoon into a friend |journal=Science |volume=313 |issue=5790 |pages=1036–1037 |issn=0036-8075 |doi=10.1126/science.313.5790.1036 |pmid=16931734}}</ref> Attracted by a low-pressure region centered over South Asia, the mass spawns surface winds that ferry humid air into India from the southwest.<ref name="Caviedes_2001_118">{{harvnb|Caviedes|2001|p=118}}.</ref> These inflows ultimately result from a northward shift of the local jet stream, which itself results from rising summer temperatures over [[Tibet]] and the Indian subcontinent. The void left by the jet stream, which switches from a route just south of the Himalayas to one tracking north of Tibet, then attracts warm, humid air.<ref name="Burroughs_1999_138-139">{{harvnb|Burroughs|1999|pp=138–139}}.</ref> The main factor behind this shift is the high summer temperature difference between Central Asia and the Indian Ocean.<ref>{{cite journal |author=Burns SJ, Fleitmann D, Matter A, Kramers J, Al-Subbary AA |title=Indian Ocean Climate and an Absolute Chronology over Dansgaard/Oeschger Events 9 to 13 |journal=Science |volume=301 |issue=5638 |pages=635–638 |year=2003 |issn=0036-8075 |doi=10.1126/science.1086227 |pmid=12958357}}</ref> This is accompanied by a seasonal excursion of the normally equatorial [[Intertropical Convergence Zone|intertropical convergence zone]] (ITCZ), a low-pressure belt of highly unstable weather, northward towards India.<ref name="Burroughs_1999_138-139">{{harvnb|Burroughs|1999|pp=138–139}}.</ref> This system intensified to its present strength as a result of the [[Tibetan Plateau]]'s [[orogeny|uplift]], which accompanied the [[Eocene]]–[[Oligocene]] transition event, a major episode of global cooling and [[aridification]] which occurred 34–49&nbsp;mya.<ref>{{cite journal |author=Dupont-Nivet G, Krijgsman W, Langereis CG, Abels HA, Dai S, Fang X |title=Tibetan plateau aridification linked to global cooling at the Eocene–Oligocene transition |journal=Nature |volume=445 |issue=7128 |pages=635–638 |year=2007 |issn=0028-0836 |doi=10.1038/nature05516}}</ref> The southwest monsoon arrives in two branches: the [[Bay of Bengal]] branch and the [[Arabian Sea]] branch. The latter extends toward a low-pressure area over the Thar Desert and is roughly three times stronger than the Bay of Bengal branch. The monsoon typically breaks over Indian territory by around [[25 May]], when it lashes the [[Andaman and Nicobar Islands]] in the Bay of Bengal. It strikes the Indian mainland around [[1 June]] near the [[Malabar Coast]] of Kerala.<ref name="IMD_swsm_onset">{{cite web |url=http://www.imd.gov.in/section/climate/monsoon-onset.htm |title=Southwest Monsoon: Normal Dates of Onset|publisher= India Meteorological Department|accessdate=2007-07-13}}</ref> By [[9 June]], it reaches [[Mumbai]]; it appears over [[Delhi]] by [[29 June]]. The Bay of Bengal branch, which initially tracks the Coromandal Coast northeast from [[Cape Comorin]] to [[Orissa]], swerves to the northwest towards the [[Indo-Gangetic Plain]]. The Arabian Sea branch moves northeast towards the Himalayas. By the first week of July, the entire country experiences monsoon rain; on average, South India receives more rainfall than North India. However, [[North-East India|Northeast India]] receives the most precipitation. Monsoon clouds begin retreating from North India by the end of August; it withdraws from Mumbai by [[5 October]]. As India further cools during September, the southwest monsoon weakens. By the end of November, it has left the country.<ref name="Burroughs_1999_138-139"/> [[Image:Mumbai india monsoon clouds.jpg|thumb|right|Pre-monsoon clouds, as they appear in [[Mumbai]], western Maharashtra.]] <!--[[Image:Ladakh india monsoon clouds.jpg|thumb|left|The monsoon over Ladakh, in eastern Jammu and Kashmir.]]--> Monsoon rains impact the health of the [[economy of India|Indian economy]]; as [[agriculture in India|Indian agriculture]] employs 600 million people and composes 20% of the national [[gross domestic product|GDP]],<ref name="CIA">{{cite web |title=CIA Factbook: India |work=CIA Factbook |url=https://www.cia.gov/library/publications/the-world-factbook/geos/in.html |accessdate=2007-03-10}}</ref> good monsoons correlate with a booming economy. Weak or failed monsoons (droughts) result in widespread agricultural losses and substantially hinder overall economic growth.<ref name="BBCW">{{cite web |url=http://www.bbc.co.uk/weather/features/understanding/monsoon_impacts.shtml |title=The Impacts of the Asian Monsoon |work=BBC Weather |accessdate=2007-04-23}}</ref><ref name="Vaswani_2006">{{cite news |url=http://news.bbc.co.uk/2/hi/business/5087442.stm |title=India's forgotten farmers await monsoon |work=BBC News |date=[[20 June]] [[2006]] |accessdate=2007-04-23}}</ref><ref name="BBC_2004">{{cite news |url=http://news.bbc.co.uk/2/hi/business/3585225.stm |title=India records double digit growth |work=BBC News |date=[[31 March]] [[2004]] |accessdate=2007-04-23}}</ref> The rains reduce temperatures and replenish groundwater tables, rivers, and lakes. === Post-monsoon === During the post-monsoon months of October to December, a different monsoon cycle, the northeast (or "retreating") monsoon, brings dry, cool, and dense Central Asian air masses to large parts of India. Winds spill across the Himalayas and flow to the southwest across the country, resulting in clear, sunny skies.<ref name="Caviedes_2001_119">{{harvnb|Caviedes|2001|p=119}}.</ref> Though the [[India Meteorological Department]] (IMD) and other sources refers to this period as a fourth ("post-monsoon") season,<ref name="IMD_four_seasons">{{cite web |url=http://www.imd.ernet.in/section/nhac/dynamic/TABLE-1.htm |title=Rainfall during pre-monsoon season |work=India Meteorological Department |accessdate=2007-03-26}}</ref><ref name="LOC_four_seasons">{{cite web |url=http://lcweb2.loc.gov/frd/cs/intoc.html |title=A Country Study: India |work=[[Library of Congress Country Studies]] |publisher=[[Library of Congress]] ([[Federal Research Division]]) |accessdate=2007-03-26}}</ref><ref>{{cite journal |author=Parthasarathy B, Munot AA, Kothawale DR |title=All-India monthly and seasonal rainfall series: 1871–1993 |journal=Theoretical and Applied Climatology |volume=49 |issue=4 |pages=217–224 |year=1994 |month=December |issn=0177-798X |doi=10.1007/BF00867461}}</ref> other sources designate only three seasons.<ref>{{cite journal |author=O'Hare G |title=The Indian Monsoon, Part Two: The Rains |journal=Geography |volume=82 |issue=4 |pages=335 |year=1997}}</ref> Depending on location, this period lasts from October to November, after the southwest monsoon has peaked. Less and less precipitation falls, and vegetation begins to dry out. In most parts of India, this period marks the transition from wet to dry seasonal conditions. Average daily maximum temperatures range between 28&nbsp;°C and 34&nbsp;°C (82–93&nbsp;°F). The northeast monsoon, which begins in September, lasts through the post-monsoon seasons, and only ends in March, carries winds that have already lost their moisture while crossing central Asia and the vast [[rain shadow]] region lying north of the Himalayas. They cross India diagonally from northeast to southwest. However, the large indentation made by the Bay of Bengal into India's eastern coast means that the flows are humidified before reaching [[Cape Comorin]] and rest of Tamil Nadu, meaning that the state, and also some parts of Kerala, experience significant precipitation in the post-monsoon and winter periods.<ref name="Healy"/> However, parts of West Bengal, Orissa, Andhra Pradesh, [[Rainfall in Karnataka|Karnataka]] and North-East India also receive minor precipitation from the northeast monsoon.<ref name=nemonmao>{{cite web | url = http://www.mapsofindia.com/maps/india/northeastmonsoon.htm | title = North East Monsoon in India | accessdate = 2007-04-19 | work = mapsofindia.com | publisher = Compare Infobase Limited }}</ref> == Statistics == Shown below are temperature and precipitation data for selected Indian cities; these represent the full variety of major Indian climate types. Figures have been grouped by the four-season classification scheme used by the IMD;{{Ref_label|Seasons|α|none}} year-round averages and totals are also displayed. === Temperature === {| style="clear:all; width:100%;" |- | style="vertical-align: top;" | {| class="toc" cellpadding=0 cellspacing=2 width=500px style="float:center; margin:1em 1em 1em 1em; padding:0.5e text-align:left; clear:all; margin-left:3px; font-size:85%" |+ <big>'''Average temperatures in various Indian cities (°C)'''</big><ref name="BBC_Weather_normals">{{cite web |url=http://www.bbc.co.uk/weather/world/country_guides/results.shtml?tt=TT002240 |title=Country Guide: India |work=[[BBC Weather]] |accessdate=2007-03-23}}</ref><ref name="WB_normals">{{cite web |url=http://www.weatherbase.com |title=Weatherbase |work=Weatherbase |accessdate=2007-03-24}}</ref><ref name="WU_normals">{{cite web |url=http://www.wunderground.com |title=Wunderground |work=Weather Underground |accessdate=2007-03-24}}</ref><ref name="WC_normals">{{cite web |url=http://www.weather.com |title=Weather.com |work=[[The Weather Channel (United States)|The Weather Channel]] |accessdate=2007-03-23}}</ref> |- align=center style="background:#e9e9e9;" | colspan=1 abbr="" | '''—''' ! colspan=3 abbr="winter" | Winter{{crlf}}(Jan – Feb) ! colspan=3 abbr="summer" | Summer{{crlf}}(Mar – May) ! colspan=3 abbr="monsoon" | Monsoon{{crlf}}(Jun – Sep) ! colspan=3 abbr="post-monsoon" | Post-monsoon{{crlf}}(Oct – Dec) ! colspan=1 abbr="year-round" | Year-round |- align=center ! City ! abbr="Minimum" | Min ! abbr="Average" | Avg ! abbr="Maximum" | Max ! abbr="Minimum" | Min ! abbr="Average" | Avg ! abbr="Maximum" | Max ! abbr="Minimum" | Min ! abbr="Average" | Avg ! abbr="Maximum" | Max ! abbr="Minimum" | Min ! abbr="Average" | Avg ! abbr="Maximum" | Max ! abbr="Average" | Avg |- align="center" ![[Bangalore]] |17||22||27||22||27||32||20||23||26||18||22||25||23 |- align="center" bgcolor="#eeeeee" ![[Chennai]] |22||25||29||26||30||34||26||30||34||23||26||29||28 |- align="center" ![[Guwahati]] |11||17||24||19||25||31||25||28||32||17||22||27||24 |- align="center" bgcolor="#eeeeee" ![[Kolkata]] |15||21||27||24||29||34||26||29||31||19||24||28||26 |- align="center" ![[Mumbai]] |19||24||30||24||28||32||25||28||30||23||27||31||27 |- align="center" bgcolor="#eeeeee" ![[Nagpur]] |14||22||28||24||32||40||24||27||30||16||23||28||27 |- align="center" ![[New Delhi]] |8||14||20||23||32||38||27||31||32||14||17||20||25 |- align="center" bgcolor="#eeeeee" ![[Port Blair]] |23||26||28||25||27||29||25||27||27||25||26||28||27 |- align="center" ![[Srinagar]] |&minus;2||4||6||7||14||19||16||22||30||1||8||16||13 |} | style="vertical-align: top;" align="right" | {{climate chart |[[New Delhi]] |7|18|19 |11|23|20 |15|28|15 |22|36|21 |26|39|25 |27|37|70 |27|34|237 |26|33|235 |24|33|113 |19|31|17 |13|27|9 |8|21|9 |source=[http://www.wunderground.com/NORMS/DisplayIntlNORMS.asp?CityCode=42182&Units=both Weather Underground] |float=right |clear=none }} |} === Precipitation === {| style="clear:all; width:100%;" |- | style="vertical-align: top;" align="left" | {| class="toc" cellpadding=0 cellspacing=2 width=500px style="float:center; margin:1em 1em 1em 1em; padding:0.5e text-align:left; clear:all; margin-left:3px; font-size:85%" |+ <big>'''Average precipitation in various Indian cities (mm)'''</big><ref name="BBC_Weather_normals"/><ref name="WB_normals"/><ref name="WU_normals"/> |- align=center style="background:#e9e9e9;" | colspan=1 abbr="" | '''—''' ! colspan=3 abbr="winter" | Winter{{crlf}}(Jan – Feb) ! colspan=3 abbr="summer" | Summer{{crlf}}(Mar – May) ! colspan=3 abbr="monsoon" | Monsoon{{crlf}}(Jun – Sep) ! colspan=3 abbr="post-monsoon" | Post-monsoon{{crlf}}(Oct – Dec) ! colspan=1 abbr="year-round" | Year-round |- align=center ! City ! abbr="January" | Jan ! abbr="February" | Feb ! abbr="March" | Mar ! abbr="April" | Apr ! May ! abbr="June" | Jun ! abbr="July" | Jul ! abbr="August" | Aug ! abbr="September" | Sep ! abbr="October" | Oct ! abbr="November" | Nov ! abbr="December" | Dec ! Total |- align="center" ![[Bangalore]] |–||–||10||30||110||70||100||130||170||150||60||10||900 |- align="center" bgcolor="#eeeeee" ![[Chennai]] |36||10||8||15||25||48||91||117||119||305||356||140||1,270 |- align="center" ![[Guwahati]] |8||21||47||181||226||309||377||227||199||92||25||10||1,722 |- align="center" bgcolor="#eeeeee" ![[Kolkata]] |10||31||36||43||140||297||325||328||252||114||20||5||1,601 |- align="center" ![[Mumbai]] |3||3||3||0||18||485||617||340||264||64||13||3||1,813 |- align="center" bgcolor="#eeeeee" ![[Nagpur]] ||16||22||15||8||18||168||290||291||157||73||17||19||1,094 |- align="center" ![[New Delhi]] |23||18||13||8||13||74||180||173||117||10||3||10||642 |- align="center" bgcolor="#eeeeee" ![[Port Blair]] |40||20||10||60||360||480||400||400||460||290||220||150||2,890 |- align="center" ![[Srinagar]] |74||71||91||94||61||36||58||61||38||31||10||33||658 |} | style="vertical-align: top;" align="right" | {{climate chart |[[Thiruvananthapuram]] |23|29|26 |23|29|21 |24|31|33 |25|31|125 |24|29|202 |24|28|306 |24|28|175 |24|28|152 |24|29|179 |24|29|223 |24|29|206 |23|29|65 |source=[http://www.wunderground.com/NORMS/DisplayIntlNORMS.asp?CityCode=43371&Units=both Weather Underground] |float=right |clear=none }} |} == Disasters == {{main|Natural disasters in India}} {| align="right" |- | style="vertical-align:top;" | [[Image:India climatic disaster risk map en.svg|thumb|right|Disaster-prone regions in India.]] | style="vertical-align:top;" | [[Image:India wind zone map en.svg|thumb|right|Map showing winds zones, shaded by distribution of average speeds of prevailing winds.]] |} Climate-related natural disasters cause massive losses of Indian life and property. Droughts, flash floods, cyclones, avalanches, landslides brought on by torrential rains, and snowstorms pose the greatest threats. Other dangers include frequent summer dust storms, which usually track from north to south; they cause extensive property damage in North India<ref name="Balfour_1976_995">{{harvnb|Balfour|1976|p=995}}.</ref> and deposit large amounts of dust from [[arid]] regions. Hail is also common in parts of India, causing severe damage to standing crops such as rice and wheat. === Floods and landslides === {{seealso|2007 South Asian floods}} In the Lower Himalaya, landslides are common. The young age of the region's hills result in [[lability|labile]] rock formations, which are susceptible to slippages. Rising population and development pressures, particularly from logging and tourism, cause deforestation. The result, denuded hillsides, exacerbates the severity of landslides, since tree cover impedes the downhill flow of water.<ref name="Allaby_1998_26">{{harvnb|Allaby|1998|p=26}}.</ref> Parts of the Western Ghats also suffer from low-intensity landslides. Avalanches occur in Kashmir, Himachal Pradesh, and Sikkim. Floods are the most common natural disaster in India. The heavy southwest monsoon rains cause the [[Brahmaputra River|Brahmaputra]] and other rivers to distend their banks, often flooding surrounding areas. Though they provide rice paddy farmers with a largely dependable source of natural irrigation and fertilisation, the floods can kill thousands and displace millions. Excess, erratic, or untimely monsoon rainfall may also wash away or otherwise ruin crops.<ref name="Allaby_1998_42">{{harvnb|Allaby|1998|p=42}}.</ref><ref name="Allaby_1998_15">{{harvnb|Allaby|1998|p=15}}.</ref> Almost all of India is flood-prone, and extreme precipitation events, such as flash floods and torrential rains, have become increasingly common in central India over the past several decades, coinciding with rising temperatures. Mean annual precipitation totals have remained steady due to the declining frequency of weather systems that generate moderate amounts of rain.<ref>{{cite journal |author=Goswami BN, Venugopal V, Sengupta D, Madhusoodanan MS, Xavier PK |title=Increasing trend of extreme rain events over India in a warming environment |journal=Science |volume=314 |issue=5804 |pages=1442–1445 |year=2006 |issn=0036-8075 |doi=10.1126/science.1132027 |pmid=17138899}}</ref> === Cyclones === [[Image:Cyclone 05B 1999 India Bay of Bengal satellite image NOAA cropped.jpg|thumb|right|Satellite imagery of Cyclone 05B in the [[Bay of Bengal]].]] [[Tropical cyclone]]s, which are severe storms spun off from the [[Intertropical Convergence Zone]], may affect thousands of Indians living in coastal regions. [[Tropical cyclogenesis]] is particularly common in the northern reaches of the [[Indian Ocean]] in and around the Bay of Bengal. Cyclones bring with them heavy rains, [[storm surge]]s, and winds that often cut affected areas off from relief and supplies. In the North Indian Ocean Basin, the cyclone season runs from April to December, with peak activity between May and November.<ref name="AOML_FAQ_G1">{{cite web |author=[[Atlantic Oceanographic and Meteorological Laboratory]], Hurricane Research Division |title=Frequently Asked Questions: When is hurricane season? |publisher=[[NOAA]] | accessdate=2006-07-25 |url=http://www.aoml.noaa.gov/hrd/tcfaq/G1.html}}</ref> Each year, an average of eight storms with sustained wind speeds greater than 63&nbsp;[[km/h]] (39&nbsp;[[Miles per hour|mph]]) form; of these, two strengthen into true tropical cyclones, which have sustained gusts greater than 117&nbsp;km/h (73&nbsp;mph). On average, a major ([[Saffir-Simpson Hurricane Scale|Category 3]] or higher) cyclone develops every other year.<ref name = "AOML FAQ G1"/><ref name = "AOML FAQ E10">{{cite web |author=[[Atlantic Oceanographic and Meteorological Laboratory]], Hurricane Research Division |title=Frequently Asked Questions: What are the average, most, and least tropical cyclones occurring in each basin? |publisher=[[NOAA]] |accessdate=2006-07-25 |url=http://www.aoml.noaa.gov/hrd/tcfaq/E10.html}}</ref> During summer, the [[Bay of Bengal]] is subject to intense heating, giving rise to humid and unstable air masses that produce cyclones. Many powerful cyclones, including the [[1737 Calcutta Cyclone|1737 Calcutta cyclone]], the [[1970 Bhola cyclone]], and the [[1991 Bangladesh cyclone]], have led to widespread devastation along parts of the eastern coast of India and neighboring [[Bangladesh]]. Widespread death and property destruction are reported every year in exposed coastal states such as Andhra Pradesh, [[Orissa]], Tamil Nadu, and West Bengal. India's western coast, bordering the more placid Arabian Sea, experiences cyclones only rarely; these mainly strike [[Gujarat]] and, less frequently, [[Kerala]]. In terms of damage and loss of life, [[Cyclone 05B (1999)|Cyclone 05B]], a supercyclone that struck Orissa on [[29 October]] [[1999]], was the worst in more than a quarter-century. With peak winds of {{convert|160|mi/h|km/h|0}}, it was the equivalent of a [[Saffir-Simpson Hurricane Scale|Category 5 hurricane]].<ref name="npmoc"/> Almost two million people were left homeless;<ref name="bapscare">{{cite web |url=http://baps-care.org/services/disaster/1990/1999supercyclone.htm |title=1999 Supercyclone of Orissa |year=2005 |work=BAPS Care International |accessdate=2007-04-08}}</ref> another 20 million people lives were disrupted by the cyclone.<ref name="bapscare"/> Officially, 9,803 people died from the storm;<ref name="npmoc">{{cite web |url=https://metocph.nmci.navy.mil/jtwc/atcr/1999atcr/pdf/05b.pdf |format=PDF|title=Tropical Cyclone 05B |work=Naval Maritime Forecast Center (Joint Typhoon Warning Center) |accessdate=2007-04-08}}</ref> unofficial estimates place the death toll at over 10,000.<ref name="bapscare"/> === Droughts === {{main|Drought in India}} [[Image:Niranjana dry river bed bihar india.jpg|thumb|right|The dry bed of the Niranjana River, [[Bihar]].]] Indian agriculture is heavily dependent on the monsoon as a source of water. In some parts of India, the failure of the monsoons result in water shortages, resulting in below-average crop yields. This is particularly true of major drought-prone regions such as southern and eastern Maharashtra, northern Karnataka, Andhra Pradesh, Orissa, Gujarat, and Rajasthan. In the past, droughts have periodically led to [[famine in India|major Indian famine]]s. These include the [[Bengal famine of 1770]], in which up to one third of the population in affected areas died; the 1876–1877 famine, in which over five million people died; the 1899 famine, in which over 4.5 million died; and the [[Bengal famine of 1943]], in which over five million died from starvation and famine-related illnesses.<ref name="Nash_2002_22-23">{{harvnb|Nash|2002|pp=22–23}}.</ref><ref name="Collier_2002_67">{{harvnb|Collier|Webb|2002|p=67}}.</ref> All such episodes of severe drought correlate with [[El Niño-Southern Oscillation]] (ENSO) events.<ref name="Kumar_2006">{{cite journal |author=Kumar KK, Rajagopatan B, Hoerling M, Bates G, Cane M |title=Unraveling the Mystery of Indian Monsoon Failure During El Niño |journal=Science |volume=314 |issue=5796 |pages=115–119 |year=2006 |issn=0036-8075 |doi=10.1126/science.1131152 |pmid=16959975}}</ref><ref name="Caviedes_2001_121">{{harvnb|Caviedes|2001|p=121}}</ref> El Niño-related droughts have also been implicated in periodic declines in Indian agricultural output.<ref name="Caviedes_2001_259">{{harvnb|Caviedes|2001|p=259}}.</ref> Nevertheless, ENSO events that have coincided with abnormally high sea surfaces temperatures in the Indian Ocean—in one instance during 1997 and 1998 by up to 3&nbsp;°C (5&nbsp;°F)—have resulted in increased oceanic evaporation, resulting in unusually wet weather across India. Such anomalies have occurred during a sustained warm spell that began in the 1990s.<ref name="Nash_2002_258-259">{{harvnb|Nash|2002|pp=258–259}}.</ref> A contrasting phenomenon is that, instead of the usual high pressure air mass over the southern Indian Ocean, an ENSO-related oceanic low pressure convergence center forms; it then continually pulls dry air from Central Asia, desiccating India during what should have been the humid summer monsoon season. This reversed air flow causes India's droughts.<ref name="Caviedes_2001_117">{{harvnb|Caviedes|2001|p=117}}.</ref> The extent that an ENSO event raises [[sea surface temperature]]s in the central [[Pacific Ocean]] influences the degree of drought.<ref name="Kumar_2006"/> == Extremes == <!--[[Image:Gulmarg-Gondala.JPG|thumb|right|[[Gulmarg]] in eastern Kashmir is one of India's snowiest places.]]--> [[Image:Alwar rajasthan india cropped.JPG|right|thumb|right|Alwar, on the fringes of the Thar Desert, registered a temperature of {{convert|50.6|°C|°F|0}}, India's highest.]] <!--[[Image:Cherrapunji.jpg|thumb|right|Cherrapunji in Meghalaya is the world's rainiest place, holding the world record for annual precipitation.]]--> India's lowest recorded temperature reading was &minus;45&nbsp;°C (&minus;49 °F) in [[Dras]], Ladakh, in eastern Jammu and Kashmir; however, the reading was taken with non-standard equipment. Further south, readings as low as {{convert|-30.6|°C|°F|0}} have been taken in [[Leh]], also in Ladakh. However, temperatures on the Indian-controlled [[Siachen Glacier]] near [[Bilafond La]] ({{convert|5450|m|ft|0}}) and [[Sia La]] ({{convert|5589|m|ft|0}}) have fallen below {{convert|-55|°C|°F|0}},<ref name="McGirk_Adiga_2005"/> while blizzards bring wind speeds in excess of 250&nbsp;km/h (155&nbsp;mph),<ref name="Ali_2002"/> or [[hurricane]]-force winds ranking at 12 (the maximum) on the [[Beaufort scale]]. It was those conditions, not actual military engagements, that were responsible for more than 97% of the roughly 15,000 casualties suffered by India and Pakistan over the course of conflict in the region.<ref name="Ali_2002">{{cite journal |author=Ali A |title=A Siachen Peace Park: The Solution to a Half-Century of International Conflict? |journal=Mountain Research and Development |year=2002 |month=November |volume=22 |issue=4 |pages=316–319 |accessdate=2007-04-06 |doi=10.1659/0276-4741(2002)022[0316:ASPPTS]2.0.CO;2}}</ref><ref>{{cite news |title=The Himalayas War at the Top Of the World |first=EW |last=Desmond |date=[[31 July]] [[1989]] |work=Time |url=http://www.time.com/time/magazine/article/0,9171,958254-1,00.html |accessdate=2007-04-07}}</ref><ref name="McGirk_Adiga_2005">{{cite news |title=War at the Top of the World |author=McGirk T, Adiga A |date=[[4 May]] [[2005]] |work=Time |url=http://www.time.com/time/asia/covers/501050711/story.html |accessdate=2007-04-07}}</ref> The highest reliable temperature reading was {{convert|50.6|°C|°F|0}} in [[Alwar]], Rajasthan in 1955. This mark was also reached at [[Pachpadra]] in Rajasthan. Recently, claims have been made of temperatures touching {{convert|55|°C|°F|0}} in Orissa;<ref>{{cite news |title=High water, heat wave, hope floats |first=Chandrika |last=Mago |date=[[20 June]] [[2005]] |work=Times News Network |publisher=Times of India (Mumbai) |format=print |page=14}}</ref> these have been met with some skepticism by the [[India Meteorological Department]] (IMD), which has questioned the methods used in recording such data. The average annual precipitation of {{convert|11871|mm|in|0}} in the village of [[Mawsynram]], in the hilly northeastern state of Meghalaya, is the highest recorded in [[Asia]], and possibly on Earth.<ref name="NCDC_extremes">{{cite web |work=National Climatic Data Center (NCDC) |title=Global Measured Extremes of Temperature and Precipitation |url=http://lwf.ncdc.noaa.gov/oa/climate/globalextremes.html#highpre |date=[[9 August]] [[2004]] |accessdate=2007-03-20}}</ref> The village, which sits at an elevation of {{convert|1401|m|ft|0}}, benefits from its proximity to both the Himalayas and the Bay of Bengal. However, since the town of [[Cherrapunji]], {{convert|5|km|mi|0}} to the east, is the nearest town to host a meteorological office (none has ever existed in Mawsynram), it is officially credited as being the world's wettest place.<ref name="BBC_Giles">{{cite web |work=BBC |title=Deluges |last=Giles |first=Bill |url=http://www.bbc.co.uk/weather/features/understanding/deluges.shtml |accessdate=2007-03-20}}</ref> In recent years, the Cherrapunji-Mawsynram region has averaged between {{convert|9296|mm|in|0}} and {{convert|10820|mm|in|0}}<ref name="Wolpert_2000_4">{{harvnb|Wolpert|2000|p=4}}.</ref> of rain annually, though Cherrapunji has had at least one period of daily rainfall that lasted almost two years.<ref>{{cite journal |author=Kushner S |title=The wettest place on Earth |journal=Faces |volume=22 |issue=9 |pages=36–37 |year=2006 |issn=0749-1387}}</ref> India's highest recorded one-day rainfall total occurred on [[26 July]] [[2005]], when Mumbai received more than {{convert|650|mm|in|0}};<ref>{{cite news |title=Millions suffer in Indian monsoon |work=BBC News |url=http://news.bbc.co.uk/2/hi/south_asia/4733897.stm |date=[[1 August]] [[2005]] |accessdate=2007-03-23}}</ref> the massive flooding that resulted killed over 900 people.<ref>{{cite news |work=The Hindu |url=http://www.hindu.com/2006/07/05/stories/2006070505741300.htm |date=[[5 July]] [[2006]] |title=Rain brings Mumbai to a halt, rescue teams deployed |accessdate=2007-03-31}}</ref><ref>{{cite news |work=BBC News |url=http://news.bbc.co.uk/2/hi/business/5219082.stm |date=[[27 July]] [[2006]] |title=Mumbai remembers last year's floods |accessdate=2007-03-23}}</ref> Remote regions of Jammur and Kashmir, such as [[Baramulla district]] in the east and the [[Pir Panjal Range]] in the southeast, experience exceptionally heavy snowfall. Kashmir's highest recorded monthly snowfall occurred in February 1967, when {{convert|8.4|m|in|0}} fell in [[Gulmarg]], though the IMD has recorded snowdrifts up to {{convert|12|m|ft|0}} in several Kashmiri districts. In February 2005, more than 200 people died when, in four days, a western disturbance brought up to {{convert|2|m|ft|0}} of snowfall to parts of the state.<ref>{{cite web |title=Snow fall and avalanches in Jammu and Kashmir |work=National Disaster Management Division (Ministry of Home Affairs, Government of India) |date=[[28 February]] [[2005]] |url=http://mha.nic.in/press-release/pr240205.pdf |format=PDF|accessdate=2007-03-24}}</ref> == Global warming == {{main|Effects of global warming on India}} {{see also|2007 South Asian heat wave}} [[Image:LakshadweepIsland.jpg|thumb|right|Lakshadweep, comprising tiny low-lying islands, are at risk of being inundated by sea level rises associated with global warming.]] Several [[effects of global warming]], including steady [[sea level rise]], increased cyclonic activity, and changes in ambient temperature and precipitation patterns, have impacted or are projected to impact India. Ongoing sea level rises have submerged several low-lying islands in the [[Sundarbans]], displacing thousands of people.<ref name="BBC_Harrabin_2007">{{cite web |work=BBC News |title=How climate change hits India's poor |last=Harrabin |first=Roger |url=http://news.bbc.co.uk/2/hi/south_asia/6319921.stm |date=[[1 February]] [[2007]] |=accessdate=2007-03-10}}</ref> Temperature rises on the Tibetan Plateau, which are causing [[retreat of glaciers since 1850|Himalayan glaciers to retreat]], may reduce the [[volumetric flow rate|flow rate]] of the Ganges, Brahmaputra, [[Yamuna]], and other major rivers; hundreds of thousands of farmers depend on these rivers.<ref name=TOI20070403>{{cite news |author=Times News Network |title=Himalayan meltdown catastrophic for India |url=http://timesofindia.indiatimes.com/Himalayan_meltdown_catastrophic_for_India/articleshow/1848002.cms |work=Times of India |publisher=Times Internet Limited |date=[[3 April]] [[2007]] |accessdate=2007-04-19}}</ref> According to a 2007 [[World Wide Fund for Nature]] (WWF) report, the [[Indus River]] may run dry for the same reason.<ref name="BBC_2007-03-20">{{cite news |url=http://news.bbc.co.uk/2/hi/science/nature/6468451.stm |title=Rivers run towards 'crisis point' |work=BBC News |date=[[20 March]] [[2007]] |accessdate=2007-03-20}}</ref> Increased landslides and flooding are projected to impact such states as Assam.<ref name="TOI_Dasgupta_2007-02-03">{{cite news |url=http://timesofindia.indiatimes.com/NEWS/India/Warmer_Tibet_can_see_Brahmaputra_flood_Assam/articleshow/1556649.cms |title=Warmer Tibet can see Brahmaputra flood Assam |work=Times of India |last=Dasgupta |first=Saibal |date=[[3 February]] [[2007]] |accessdate=2007-03-18| publisher = Times Internet Limited}}</ref> Ecological disasters, such as a 1998 [[coral bleaching]] event that killed off more than 70% of [[coral]]s in the reef ecosystems off Lakshadweep and the Andamans, and was brought on by elevated ocean temperatures tied to global warming, are also projected to become increasingly common.<ref name="Aggarwal_Lal">{{cite web |author=Aggarwal D, Lal M |title=Vulnerability of the Indian coastline to sea level rise |work=SURVAS (Flood Hazard Research Centre) |url=http://www.survas.mdx.ac.uk/pdfs/3dikshas.pdf |format=PDF|accessdate=2007-04-05}}</ref><ref name="Normile_2000">{{cite journal |author=Normile D |title=Some coral bouncing back from El Niño |journal=Science |year=2000 |month=May |volume=288 |issue=5468 |pages=941–942 |url=http://www.scienceonline.org/cgi/content/summary/288/5468/941a |accessdate=2007-04-05 |doi=10.1126/science.288.5468.941a |pmid=10841705}}</ref><ref name="UCS_2005">{{cite web |title=Early Warning Signs: Coral Reef Bleaching |work=Union of Concerned Scientists |url=http://www.ucsusa.org/global_warming/science/early-warning-signs-of-global-warming-coral-reef-bleaching.html |year=2005 |accessdate=2007-04-05}}</ref> The [[Indira Gandhi Institute of Development Research]] has reported that, if the predictions relating to global warming made by the [[Intergovernmental Panel on Climate Change]] come to fruition, climate-related factors could cause India's GDP to decline by up to 9%. Contributing to this would be shifting growing seasons for major crops such as rice, production of which could fall by 40%. Around seven million people are projected to be displaced due to, among other factors, submersion of parts of Mumbai and Chennai, if global temperatures were to rise by a mere {{convert|2|°C|°F|0}}.<ref name="TOI_Sethi_2007-02-03">{{cite news |url=http://timesofindia.indiatimes.com/NEWS/India/Global_warming_Mumbai_to_face_the_heat/articleshow/msid-1556662,curpg-1.cms |title=Global warming: Mumbai to face the heat |work=Times of India |last=Sethi |first=Nitin |date=[[3 February]] [[2007]] |accessdate=2007-03-18}}</ref> Such shifts are not new. Earlier in the [[Holocene]] [[geologic time scale|epoch]] (4,800–6,300&nbsp;years ago), parts of what is now the Thar Desert were wet enough to support perennial lakes; researchers have proposed that this was due to much higher winter precipitation, which coincided with stronger monsoons.<ref name="Enzel_1999">{{cite journal |author=Enzel Y, Ely LL, Mishra S, Ramesh R, Amit R, Lazar B, Rajaguru SN, Baker VR, Sandler A |title=High-Resolution Holocene Environmental Changes in the Thar Desert, Northwestern India |journal=Science |volume=284 |issue=5411 |pages=125 |year=1999 |issn=0036-8075 |doi=10.1126/science.284.5411.125 |pmid=10102808}}</ref> Similarly, Kashmir, which once had a warm subtropical climate, shifted to a substantially colder temperate climate 2.6–3.7&nbsp;mya; it was then repeatedly subjected to extended cold spells starting 600,000 years ago.<ref name="Pant_2003">{{cite journal |author=Pant GB |title=Long-term climate variability and change over monsoon Asia |journal=Journal of the Indian Geophysical Union |year=2003 |volume=7 |issue=3 |pages=125–134 |url=http://www.igu.in/7-3/2GBpant.pdf |format=PDF|accessdate=2007-03-24}}</ref> == Atmospheric pollution == [[Image:Hazesmoke Gangeticbasin.jpg|thumb|Clouds of thick haze and smoke form along the Ganges River Basin.]] Thick haze and smoke, originating from burning biomass in northwestern India<ref name="Badarinath_2006">{{cite journal |author= Badarinath KVS, Chand TRK, Prasad VK |title=Agriculture crop residue burning in the Indo-Gangetic Plains—A study using IRS-P6 AWiFS satellite data |journal=Current Science |year=2006 |volume=91 |issue=8 |pages=1085–1089 |url=http://www.ias.ac.in/currsci/oct252006/1085.pdf |accessdate=2007-04-16}}</ref> and air pollution from large industrial cities in northern India,<ref name="Lau_2005">{{cite web |url=http://climate.gsfc.nasa.gov/viewImage.php?id=110 |title=Aerosols may cause anomalies in the Indian monsoon |accessdate=2007-04-17 |last=Lau |first=WKM |date=[[February 20]] [[2005]] |format=php |work=The Climate and Radiation Branch at NASA's Goddard Space Flight Center |publisher=NASA }}</ref> often concentrate inside the [[Ganges Basin]]. Prevailing westerlies carry aerosols along the southern margins of the steep-faced Tibetan Plateau to eastern India and the [[Bay of Bengal]]. Dust and [[black carbon]], which are blown towards higher altitudes by winds at the southern margins of the Himalayas, can absorb shortwave radiation and heat the air over the Tibetan Plateau. The net atmospheric heating due to aerosol absorption causes the air to warm and [[convection|convect]] upwards, increasing the concentration of moisture in the mid-[[troposphere]] and providing positive feedback that stimulates further heating of aerosols.<ref name="Lau_2005"/> == See also == *[[List_of_wettest_tropical_cyclones_by_country#India|List of wettest known tropical cyclones in India]] == Notes == <div class="references-small"> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;'''α.'''&nbsp;&nbsp;&nbsp;{{Note_label|Seasons|α|none}} The IMD-designated post-monsoon season coincides with the northeast monsoon, the effects of which are significant only in some parts of India. </div> == References == [[Image:Monsoon season beach Tamil Nadu India.jpg|thumb|right|Late-season monsoon clouds during a sunset over the [[Coromandel Coast]].]] <div class="references-small"> * {{harvard reference |Last1=Allaby |Given1=M |Title=Floods |Year=1998 |Publisher=Facts on File |ID=ISBN 0-8160-3520-2}}. * {{harvard reference |Last1=Allaby |Given1=M |Title=Encyclopedia of Weather and Climate |Year=2002 |Publisher=Facts on File |ID=ISBN 0-8160-4071-0}}. * {{harvard reference |Last1=Balfour |Given1=E |Title= Encyclopaedia Asiatica: Comprising Indian Subcontinent, Eastern and Southern Asia |Year=1976 |Publisher=Cosmo Publications |isbn=8170203252}}. * {{harvard reference |Last1=Burroughs |Given1=WJ |Title=The Climate Revealed |Year=1999 |Publisher=Cambridge University Press |ID=ISBN 0-521-77081-5}}. * {{harvard reference |Last1=Caviedes |Given1=C |Year=2001 |Title=El Niño in History: Storming Through the Ages |Publisher=University Press of Florida |ID=ISBN 0-8130-2099-9}}. * {{harvard reference |Last1=Chouhan |Given1=TS |Year=1992 |Title=Desertification in the World and Its Control |Publisher=Scientific Publishers |ID=ISBN 8-1723-3043-X}}. * {{harvard reference |Last1=Collier |Given1=W |Last2=Webb |Given2=R |Year=2002 |Title=Floods, Droughts and Climate Change |Publisher=University of Arizona Press |ID=ISBN 0-8165-2250-2}}. * {{harvard reference |Last1=Heitzman |Given1=J |Last2=Worden |Given2=RL |Year=1996 |Title=India: A Country Study |Publisher=Library of Congress (Area Handbook Series) |ID=ISBN 0-8444-0833-6}}. * {{harvard reference |Last1=Nash |Given1=JM |Year=2002 |Title=El Niño: Unlocking the Secrets of the Master Weather Maker |Publisher=Warner |ID=ISBN 0-446-52481-6}}. * {{harvard reference |Last1=Posey |Given1=CA |Year=1994 |Title=The Living Earth Book of Wind and Weather |Publisher=Reader's Digest Association |ID=ISBN 0-8957-7625-1}}. * {{harvard reference |Last1=Singh |Given1=VP |Last2=Ojha |Given2=CSP |Last3=Sharma |Given3=N |Year=2004 |Title=The Brahmaputra Basin Water Resources |Publisher=Springer |ID=ISBN 1-4020-1737-5}}. * {{harvard reference |Last1=Wolpert |Given1=S |Authorlink=Stanley Wolpert |Year=2000 |Title=A New History of India |Publisher=Oxford University Press |ID=ISBN 0-19-512877-X |url=http://www.amazon.com/New-History-India-Stanley-Wolpert/dp/0195166787/}}. </div> == Citations == {{reflist|2}} == Further reading == <div class="references-small"> * {{harvard reference |Last1=Toman |Given1=MA |Last2=Chakravorty |Given2=U |Last3=Gupta |Given3=S |Title=India and Global Climate Change: Perspectives on Economics and Policy from a Developing Country |Year=2003 |Publisher=Resources for the Future Press |ID=ISBN 1-8918-5361-9}}. </div> == External links == {{commons|Atlas of India}} {{portal|Environment}} {{portal|India|Flag of India.svg}} <div class="references-small"> ; General overview * {{cite web |url=http://www.bbc.co.uk/weather/world/country_guides/results.shtml?tt=TT002240 |title=Country Guide: India |work=[[BBC Weather]]}} * {{cite web |url=http://www.hcilondon.net/tourism-information/weather.html |title=India—Weather and Climate |work=[[Indian diplomatic missions|High Commission of India, London]]}} ; Maps, imagery, and statistics * {{cite web |url=http://www.imd.gov.in/ |title=India Meteorological Department |work=[[Government of India]]}} * {{cite web |url=http://www.weather.nic.in/ |title=Weather Resource System for India |work=[[National Informatics Centre]]}} ; Forecasts * {{cite web |url=http://weather.noaa.gov/weather/IN_cc.html |title=India: Current Weather Conditions |work=[[National Oceanic and Atmospheric Administration]] (NOAA)}} </div> <!--===========================({{NoMoreLinks}})===============================--> <!--| DO NOT ADD MORE LINKS TO THIS ARTICLE. WIKIPEDIA IS NOT A COLLECTION OF |--> <!--| LINKS. If you think that your link might be useful, do not add it here, |--> <!--| but put it on this article's discussion page first or submit your link |--> <!--| to the appropriate category at the Open Directory Project (www.dmoz.org)|--> <!--| and link back to that category using the {{dmoz}} template. |--> <!--| |--> <!--| Links that have not been verified WILL BE DELETED. |--> <!--| See [[Wikipedia:External links]] and [[Wikipedia:Spam]] for details |--> <!--===========================({{NoMoreLinks}})===============================--> {{featured article}} <!--Footer templates--> {{Life in India}} <!--Categories--> [[Category:Climate of India| ]] <!--Interwiki--> [[es:Clima de la India]] [[fr:Climat en Inde]] [[hi:भारत की जलवायु]] [[nl:Klimaat in India]] [[nn:Klima i India]] [[pt:Clima da Índia]] [[ta:இந்தியாவின் தட்பவெப்ப நிலை]]