mausam vigyaan

vaayuvegamaapi

rituvijnyaaan ya mausam vigyaan (Meteorology) kai vidhaaon ko samete hue vigyaan hai jo vaayumandal ka adhyayan karta hai. mausam vigyaan mein mausam ki prakriya evam mausam ka poorvaanumaan adhyayan ke kendrabindu hote hain. mausam vigyaan ka itihaas hajaaron varsh puraana hai kintu atthaarahaveen shati tak ismein khaas pragati naheen ho saki thi. unneesaveen shati mein vibhinn deshon mein mausam ke aakadon ke prekshan se ismein gati aayi. beesaveen shati ke uttaraardh mein mausam ki bhavishyavaani ke liye computer ke istemaal se is kshetr mein kraanti aa gayi.

mausam vigyaan ke adhyayan mein pruthvi ke vaayumandal ke kuchh charon (variables) ka prekshan bahut mahatva rakhata hai; ye char hain - taap, hava ka daab, jal vaashp ya aardrata aadi. in charon ka maan va inke parivartan ki dar (samay aur doori ke saapeksh) bahut had tak mausam ka nirdhaaran karte hain.

rituvijnyaaan vaayumandal ka vigyaan hai. aadhunik rituvijnyaaan mein vaayumandal mein honevaali bhautik ghatnaaon ka tatha unase sambaddh upalagole (lithosfiyr) aur jalagole (haaidrosfiyr) ki ghatnaaon ka adhyayan kiya jaata hai. rituvijnyaaan ke vishay ka varnan, jahaaain tak usaka sambandh nichle vaayumandal ki mausami ghatnaaon se hain, adhiktam suvidhaapoorvak nimnalikhit chaar bhaagon mein kiya ja sakta hai:

(1) yaantrik rituvijnyaaan (fijikl aur daainaimikl meetiarauloji) jiska sambandh un prekshanayantron tatha prekshanavidhiyon se hai jinke dvaara vaayumandal ki rituprabhaavak avasthaaon ki soochana praapt ki jaati hai.

(2) bhautik tatha gatik rituvijnyaaan (fijikl aur daainaimikl meetiarauloji) jismein prekshit ritu sambandhi ghatnaaon ka gunaatmak tatha paarimaanik (kvaantitetiv) vivechan kiya jaata hai.

(3) sankshipt rituvijnyaaan (sinaushtik meetiarauloji) jo mukhyat: ritu ke poorvaanumaan ke liye sankshipt aartav (ritu sambandhi) maanachitron dvaara sankshipt aartav prekshanon ke adhyayan se sambandh rakhata hai.

(4) jalavaayu-tatv (klaaimaitauloji) jismein sansaar ke sab bhaagon ke aartav prekshanon ka saankhyikeeya (staitistikl) adhyayan hota hai aur uske dvaara un prasaamaanya tatha madhyamaan (ausat) paristhitiyon ka theek-theek pata lagaaya jaata hai jiske dvaara jalavaayu ka varnan kiya ja sakta hai.

ritu sambandhi prekshanon mein, jinse vaayumandal ki dasha ka gyaan milta hai, nimnalikhit baatein dekhi jaati hain :

taap

vaayu ka taap taapamaapi (tharamaameetar) dvaara naapa jaata hai. is tharamaameetar ko saur vikirnon se aprabhaavit rakha jaata hai. vaayu ki aardrata gyaat karne ke liye geele taapamaapi (vet balb tharamaameetar) ka upayog kiya jaata hai. is tharamaameetar ke balb par geele malamal ke kapde ki ikahari tah lipti rahati hai. aardrata ki maatra sookhe tharamaameetar tatha geele tharamaameetar ke paathayaankon se nikaali jaati hai.

vaayudaab

yeh vaayudaabamaapi (bairomeetar) dvaara maapa jaata hai aur isse pruthvi par vaayu ka bhaar (prati ikaai kshetrafal) vidit hota hai.

pavan

pavan ki disha tatha veg ka prekshan kiya jaata hai. disha vah li jaati hai jis or se pavan aata hai aur diksoochak ke 16 athva 32 binduon mein ankit ki jaati hai. veg pavan-vegamaapi (ainimomeetar) dvaara maapa jaata hai aur meal prati ghanta ya kilometer prati ghanta ya meter prati second mein vyakt kiya jaata hai.

aardrata

aardrata se vaayumandal mein jalavaashp ki maatra ka gyaan hota hai aur, jaisa pehle kaha ja chuka hai, yeh sookhe tatha geele tharamaameetaron dvaara naapi jaati hai.

sanghanan ke roop (kandeinseshan faarms)

ismein vaayumandaleeya sanghanan ke sab prakaar ke drav evam thos utpaadan sanmilit hain. baadalon ki maatra tatha unke prakaar, kuhara tatha varsha, him (barf), ola aadi, ka prekshan kiya jaata hai. pratyek prakaar ka baadal aakaash ke jitne bhaag mein vyaapt ho utane ko poore aakaash ke dashaanshon mein vyakt kiya jaata hai. jo sanghanan kan kaafi bade hote hain ve varsha ke roop mein pruthvi par girte hain.

drushyata (vijibiliti)

us kshaitij doori ko kehte hain jahaaain tak ki badi aur spasht vastueain dikhaai de sakti hon.

chhaadan (seeling)

oordhvaadhar drushyata (vartikl vijibiliti) se sambandh rakhati hai aur meghatal ki ooainchaai se maapi jaati hai.

praacheen kaal se hi manushya ritu tatha jalavaayu ki anek ghatnaaon se prabhaavit hota raha hai. vaayuvijnyaaan ke praacheenatam granth airistautal (384-322 E.poo.) rachit 'meetiarolaujika' tatha unke shishyon ki pavan tatha ritu sambandhi rachanaaeain hain. airistautal ke pashchaat‌ agale do hajaar varsho mein rituvijnyaaan ki adhik pragati naheen hui. 17veen tatha 18veen shataabdi mein mukhyat: yantraprayog tatha gas aadi ke niyam sthaapit hue. isi kaal mein taapamaapi ka aavishkaar san‌ 1607 mein gaileeliyon geleeli ne kiya aur eveinjeelista taureeseli ne san‌ 1643 mein vaayu daabamaapi yantr ka aavishkaar kiya. in aavishkaaron ke pashchaat‌ san‌ 1659 mein vaayal ke niyam ka aavishkaar hua. san‌ 1735 mein George haidale ne vyaapaarik vaayu (traid vind) ki vyaakhya prastut ki tatha usamein haidale ne vyaapaarik vaayu (trade vind) ki vyaakhya prastut ki tatha usamein sabse pehle vaayumandaleeya pavanon par pruthvi ke chakkar ke prabhaav ko sammilit kiya. jab san‌ 1783 mein aintoni levosiye ne vaayunmadal ki vaastavik prakruti ka gyaan praapt kar liya aur san‌ 1800 mein John daultan ne vaayumandal mein jalavaashp ke parivrtanon par aur vaayu ke prasaar tatha vaayumandaleeya sanghanan ke sambandh par prakaash daala tabhi aadhunik rituvijnyaaan ka aadhaar sthaapit ho gaya. 19veen shataabdi mein vikaas adhiktar sankshipt rituvijnyaaan ke kshetr mein hua. anek deshon ne rituvaijnyaaanik sansthaaeain sthaapit ki aur ritu vedhashaalaaeain kholeen. is kaal mein ritu poorvaanumaan ki disha mein bhi paryaapt vikaas hua. 20 veen shataabdi ke poorvaardh mein 20 kilometer ki ooainchaai tak vaayu ke veg tatha disha aadi ke prekshanon ke badh jaane ke kaaran jo soochanaaeain rituvisheshajnyaon ko praapt hone lageen unase rituvijnyaaan ki adhik unnati hui. oopari vaayu ke aise prekshanon se rituvijnyaaan ki anek samasyaaon ko samajhne mein bahut adhik sahaayata mili.

pratham vishvayuddh kaal mein vaayumandaleeya sthitiyon ke adhik aur sheeghratam prekshanon ki aavashyakta hui jiski poorti ke liye vaayuyaan dvaara ritulekhi yantr (meetiarograaf) oopar le jaane ki vyavastha ki gayi. anya mahatvapoorn pragatiyaaain jo pratham vishvayuddh kaal mein hui ve Norway desh ke rituvisheshajnya vi.barakaneej H. solavarg tatha J. barakaneej dvaara dhraveeya agrasiddhaant (polar frant theory) ke tatha chakravaaton ki utpatti ke tarang siddhaant ke parinaam hain.

dviteeya vishvayuddh kaal mein mukhyat: adhik ooainchaai par udnevaale vaayuyaanon ke upayog ke liye ritu sambandhi soochanaaon ki maaaing aur badh gayi aur is maaaing ki poorti ke nirmitt vibhinn ooainchaaiyon par vaayu ke veg tatha disha aadi ke gyaan ke liye raadaar pravidhi (raadaar tekaneek) ka vikaas hua.

nichle vaayumandal ki sookhi vaayu mein anek gaison ka mishran hota hai jinmein mukhyat: naaitrojan 78 pratishat, aaksijn 21 pratishat, aaragan 0.93 pratishat aur kaarban daaiaaksaaid 0.03 pratishat hoti hain. in gaison ke atirikt kuchh anya gaisein bhi hoti hain, jaise haaidrojan tatha ojon. pavanon dvaara nichle vaayumandal ke lagaataar mishran se tatha oordhvaadhar sanvahan (kanavekshan) se sookhi hava ka mishran itna aparivrti rahata hai ki kam se kam 20 kilometer ki ooainchaai tak to sookhi hava ka anubhaar 28.96 par sthir rahata hai; arthaat‌ vaayu ka ghanatv 1.276 (10)3 gram prati ghan sein. hota hai, jab vaayu daab 1,000 mileebaar ho aur taap 0° seinteegred ho.

vaayumandal mein ojon ki upasthiti faaular tatha strat ne varnakramadarshi yantr (spektrauskop) dvaara pramaanit ki thi. daubasan ke prekshanon se bhi yeh baat siddh ho gayi hai tatha yeh gyaan bhi praapt hua hai ki ojon bhootal se lagbhag 30 se 40 kilometer ki ooainchaai par ek seemit star mein pai jaati hai. in ooainchaai par ojon ki upasthiti mausami paristhitiyon ke liye kuchh mahatvapoorn hai. daubasan ki khoj se pata laga hai ki 10 kilometer ooainchaai par ki vaayudaab mein aur ojon ki maatra mein ghanishth sambandh hai.

vaayumandal mein keval jalavaashp hi aisa avayav hai jiski bhautik avastha ka parivartan saamaanya vaayumandaleeya paristhitiyon mein hota rahata hai. at: vaayumandal mein jalavaashp ki pratishat aayatan maatra bahut ghatati badhti rahati hai. vaayumandal mein jalavaashp ka ghatna badhna rituvijnyaaan ke liye atyant mahatvapoorn hai. jal ka vaashpeekaran tatha sanghanan isliye mahatvapoorn hai ki na keval inse ek sthaan se doosare sthaan ko jal ka parivhan hota hai, varan‌ isliye bhi ki jal ke vaashpeekaran ke liye gupt ushma ke avashoshan ki aavashyakta hoti hai. yeh ant mein pun: prakat hokar vaayu ko tab ushn karne ke kaam mein aati hai jab jalavaashp ka fir se jalabindu tatha him mein sanghanan hota hai.

yadyapi naaitrojan gas amoniya, naaitrik aml tatha naaitreton ka mukhya avayav hai aur ye padaarth baarood aadi mein bahut mahatva rakhate hain, tathaapi vaayumandal mein yeh gas bilkul nishkriya rahati hai. yeh to vaayumandal ke adhik mahatvapoorn avayav aaksijn gas ko, jo vaayumandal ka lagbhag paaainchavaaain bhaag hoti hai, keval tanu kar deti hai.

kisi bhi sthaan ki vaayudaab vahaaain ke oopar ki vaayu ke bhaar se utpann hoti hai, isliye do vibhinn ooainchaaiyon ki vaayudaabon ka antar in donon ooainchaaiyon ke beech ki hava ke ekaank anuprasth kaat (kraus sekshan) ke bhaar ke baraabar hota hai. yadi yeh daab ka antar beech ki hava ke bhaar se yathaarth roop mein santulit na ho to us vaayustar ko oopar ki or ya neeche ki or tvaran (aikselareshan) praapt hota hai. jis paristhiti mein daab ka antar aur vaayu ka bhaar santulit ho, athva yon kahiye ki gurutvajanit tvaran ke atirikt koi anya oordhvaadhar tvaran vidyamaan na ho, vah dravasthaitik santulan (haaidrostaitik ikvilibriym) ki paristhiti kahalaati hai. yeh paristhiti kisi bhi star par ooainchaai ke saath daabaparivrtan ki dar ka parichay deti hai. yadi do daabastaron ke beech ka daab antar (dp) ho aur donon staron ke beech oordhvaadhar doori (dz) ho, ghanatv (p) ho aur gurutvajanit tvaran (g) ho, to

dp/dz = -pMg/(RT)

is sameekaran ko dravasthaitik sameekaran kehte hain.

gurutvajanit tvaran vibhinn akshaansh (laitityood) tatha ooainchaai ke kaaran thoda sa hi ghatata badhta hai, kintu daab, taap tatha nami ke kaaran vaayu ka ghanatv adhik maatra mein ghatata badhta hai. isliye vaayumandal mein oordhvaadhar daabapravanata (vartikl preshar grediyant) atyant parivrtanasheel hoti hai.

68 kimi ke neeche daab ki ganana ke liye do sootr prayog mein laaye jaate hain. pehle sootr ka prayog tab kiya jaata hai jab maanak taapamaan lesp dar (Lapse Rate) shoonya na ho. doosare ka prayog tab karte hain jab maanak taap leps dar (standard temperature lapse rate) shoonya ho.

pehla sameekaran:

${\displaystyle {P}=P_{b}\cdot \left[{\frac {T_{b}}{T_{b}+L_{b}\cdot (h-h_{b})}}\right]^{\textstyle {\frac {g_{0}\cdot M}{R^{*}\cdot L_{b}}}}}$

doosra sameekaran:

${\displaystyle P=P_{b}\cdot \exp \left[{\frac {-g_{0}\cdot M\cdot (h-h_{b})}{R^{*}\cdot T_{b}}}\right]}$

jahaaain

${\displaystyle P_{b}}$ = Static pressure (pascals)

${\displaystyle T_{b}}$ = Standard temperature (K)

${\displaystyle L_{b}}$ = Standard temperature lapse rate -0.0065 (K/m) in ISA

${\displaystyle h}$ = Height above sea level (meters)

${\displaystyle h_{b}}$ = Height at bottom of layer b (meters; e.g., ${\displaystyle h_{1}}$ = 11,000 meters)

${\displaystyle R^{*}}$ = Universal gas constant for air: 8.31432 N·aam /(mol·aK)

${\displaystyle g_{0}}$ = Gravitational acceleration (9.80665 m/s²)

${\displaystyle M}$ = Molar mass of Earth's air (0.0289644 kg/mol)

Or converted to English units:^[1]

jahaaain

${\displaystyle P_{b}}$ = Static pressure (inches of mercury, inHg)

${\displaystyle T_{b}}$ = Standard temperature (K)

${\displaystyle L_{b}}$ = Standard temperature lapse rate (K/ft)

${\displaystyle h}$ = Height above sea level (ft)

${\displaystyle h_{b}}$ = Height at bottom of layer b (feet; e.g., ${\displaystyle h_{1}}$ = 36,089 ft)

${\displaystyle R^{*}}$ = Universal gas constant; using feet, kelvins, and (SI) moles: 8.9494596×a10⁴ lb·aaft²/(lbmol·aK·aas²)

${\displaystyle g_{0}}$ = Gravitational acceleration (32.17405 ft/s²)

${\displaystyle M}$ = Molar mass of Earth's air (28.9644 lb/lbmol)

ooainchaai maapane ki praamanik vidhi yeh hai ki oopar diye hue sootr dvaara daab tatha taap maapakar ooainchaai ka antar praapt kiya jaae aur yadi yathaarthata ki aavashyakta ho to aardrata ki maatra ko bhi kaam mein laaya jaae. praamaanik tungataamaapi (aaltimeetar) isi sootr par aadhaarit hai.

din ke samay soorya se garami milne aur raat mein vikirn dvaara pruthvi ke thandi hone se vaayu ke taap mein dainik parivartan utpann hota hai. nyoonatam taap sooryodaya se kuchh pehle hota hai aur adhiktam taap teesare pahar mein hota hai. vaayu ke taap ka yeh dainik parivartan bhootal ke oopar se mukt vaayumandal mein sheeghrata se ghatata hai. pruthvi ke adhiktar bhaagon mein 5,000 foot se adhik ki ooainchaaiyon par tatha registaani pradeshon mein 10,000 foot ki ooainchaai par taap ka dainik paraas (range) 2° ya 3° seinteegred se adhik naheen paaya gaya hai.

bhootal tatha vaayumandal ko garami lagbhag poornataya sooryavikirn se hi milti hai. anya aakaasheeya pindon se garami bahut hi kam maatra mein milti hai. saur oorja ki maapein smithsoniyn sanstha ki taara-bhautiki-vedhashaala mein tatha anya kai parvatashikhron par sthit vedhashaalaaon mein niyamit roop se ki jaati hai aur in maapon ki yathaarthata ek pratishat se utkrusht hoti hai. pruthvi aur soorya ki madhyamaanasaur doori par yeh saur aatapan oorja vaayumandal mein pravisht hokar anshat: avasheshit hone ke pehle lagbhag 1.94 gram kalari prati minute varg seinteemeetar hoti hai; yahaaain pratibandh yeh hai ki soorya ki kirnein us varg seinteemeetar par abhilanbat: padein. is maatra ko saur niytaank (solar kaunstaint) kehte hain. saur niytaank ke maan mein pai gayi aniyamit ghat badh ek pratishat se bhi kam rahati hain; ye prekshanatrutiyon ke kaaran ho sakti hain. in aniyamit uchchaavachanon ke atirikt ek vaastavik aur bada uchchaavachan bhi paaya gaya hai jo gyaarah varsheeya soorya-kalank-chakr mein lagbhag pratishat tak ka deerghakaalik uchchaavachan aur bhi ho sakta hai. parantu ye sab uchchaavachan itne laghu hain ki vaayumandaleeya ushm santulan ke sambandh mein yeh maan liya ja sakta hai ki pruthvi par saur oorja 1.94 gram kalari prati varg seinteemeetar prati minute padti hai. anumaan kiya gaya hai ki saur oorja ka 43 pratishat bhaag paraavartit tatha prakeernit tatha prakeernan karne ki sammilit shakti ko ailabedo kehte hain. yeh 43 pratishat hai. shesh 57 pratishat oorja, jo prabhaavakaari aatapan hai, bhootal tatha vaayumandal ko ausatan 57 ushma ikaaiyaaain pradaan karta hai. in 57 ushma ikaaiyon mein se keval ek laghu bhaag ka (adhik se adhik 14 ikaaiyon ka) vaayumandal, mukhyat: nichle staron mein jalavaashp dvaara aur kuchh kam parimaan mein oopari samataap mandal (straitosfiyr) mein ojon dvaara, avashoshan kar leta hai.

vaayumandal mein vaashpan tatha sanghanan ka kaaran hai vaayu ki jalavaashp grahan karne ki shakti mein kami beshi, arthaat‌ aardr vaayu ka garam ya sheetal hona. saadhaaranat: vaayumandal mein jalavaashp-maatra santrupt maatra se kam hoti hai, visheshakar bhootal ke sameep jahaaain vaayumandal ka prabhaavakaari aatapan adhiktam hota hai.

vaashpan

vaayu mein nami ka adhik bhaag, jo vaayumandal mein jalavaashpachakr ko chalaata rahata hai, vaashpan se praapt hota hai. jaise-jaise jal vaashpit hota hai, taise taise vah vaayumandal mein visrit hota rahata hai. vaayumandal mein vaashpan dvaara honevaali mausami kriyaaeain apekshaakrut mahatvapoorn naheen hoteen. drushya bhaap ki uttapati bhi vaashpan dvaara honevaali mausami kriya hai. garam jal ki satah se sheeghrataapoorvak vaashpan hone ke kaaran bahut thandi athva apekshaakrut thandi aardr vaayu ekdam ati santrupt ho jaati hai. iska parinaam yeh hota hai ki drushya bhaap ke roop mein nami ka turant sanghanan ho jaata hai jiske kaaran sthir hava mein ghana kohara ban jaata hai.

vaayumandaleeya sanghanan

sanghanan kisi khuli satah par us samay hota hai jab us satah ka taap aaspaas ki vaayu ke osaank (dayoo point) ke taap se kam hota hai. is prakaar ke sanghanan ke udaaharan garam mausam mein paae jaate hain. jaise, yadyapi vaayu ki aapekshik aardrata sau pratishat se paryaapt kam rahane par bhi barf ke paani se bhare gilaas ke baahar vaayu ka vaashp sanghanit ho jaata hai usi prakaar svachh prashaant raatri mein os ka sanghanan un bhootalasthit vastuon par ho jaata hai jo apni ooshma ke vikirn ke kaaran aaspaas ki vaayu ke osaank se nimn taap tak thandi ho jaati hain, paala un satahon par jamata hai jo hinmaak se bhi adhik thandi ho jaati hain, chaahe mukt vaayu ka taap himaank se kaafi ooaincha ki kyon na ho.

jab vaayumandal ke bheetar chhote chhot jalabinduon ke roop mein sanghanan hota hai to prashn yeh uthata hai ki yeh prakram kis prakaar praarambh hota hai. prayog se siddh hua hai ki poornat: ashuddhiheen vaayu mein sanghanan jalabindu ke roop mein naheen hota, chaahe usamein vaashpadaab santrupti daab se das guni hi kyon na ho. prateet hota hai ki jalavaashp ka sanghanan praarambh karne ke liye kisi prakaar ke kanon ki aavashyakta hoti hai jo shuddh vaayu mein upasthit naheen hote. is prakaar ke kan ko sanghanan naabhik kehte hain. pareekshan se gyaat hua hai ki vaayu mein jalaakarshi padaarthon ke nanhein kan, jaise samudri namak ke kan, sanghanan naabhikon ka kaarya karte hain. jin sthaanon mein kaarkhaanon ka dhuaaain vaayumandal ko dooshit kar deta hai, vahaaain dhueain ke gandhak, faasaforas aadi padaartho ke aaksaaid ke nanhein kan sanghanan naabhik ban jaate hain.

saadhaaranat: nichle kshobhamandal (trauposfiyr) ke kuhare aur baadalon mein prati ghan seinteemeetar sau se das hajaar tak nanhein jalabindu hote hain. baadalon mein vashabindu athva doosare varshanakan kis prakaar nirmit hote hain, yeh vishay abhi sanshayayukt hai. kadaachit‌ ye bahut se chhote-chhote meghakanon ke sanyojan dvaara bante hain. sanyojan vaayu ki dhaaraaon ke milne aur vaayu ke math uthane se hota hoga. bade bade binduonvaali teevr varsha ke baare mein sveekrut siddhaant yeh hai ki ye bindu tab bante hain jab himmanibh baadalon ke oopari bhaagon mein pahuainch jaate hain jahaaain ati sheet (sooparakoold) jalakaran vidyamaan rahate hain. is siddhaant ka pratipaadan ti vargaraan ne kiya tha.

moolat: vaayumandal ka saamaanya sanchaar bhoomadhyeeya tatha dhraveeya deshon ke beech kshaitij taapapravanata (grediyant) ke kaaran utpann hota hai. ek prakaar ke vaayumandal ka saamaanya sanchaar vaayumandal ki halachal ka tatha usaki kriyaaon ka ek vyaapak vihangam chitr hai. yadi deerghakaal ke dainik mausami nakshon ka pareekshan kiya jaae to yeh gyaat hota hai ki unamein pravaah ke roop do prakaar ke hote hain :

(1) alpajeevi sheeghragaami pratichkravaat (aintisaaiklon) tatha avadaab (dipreshan). is prakaar ke bhainvar praarambh hone ke baad ek din se lekar ek maas tak ke kaal mein samaapt hote hain aur fir nakshon se bilkul adrushya ho jaate hain. ye gaun sanchaar naam se prasiddh hain.

(2) deerghajeevi tatha dheere-dheere chalanevaale bhainvar. ye bhi pratichkravarti athva chakravaati prakaar ke hote hain, parantu deergh kaal tak lagbhag nishchal rahate hain. ye praathamik sanchaar kahalaate hain. chitr 1 aur 2 mein January aur July ke maheenon mein pruthvi par ausat samudrastareeya daabarekhaaeain di gayi hain. yeh spasht hai ki donon chitron mein dakshini golaardh ki kuchh baatein ek jaisi hain.

(k) donon maheenon mein pruthvi ke samast bhoomadhyarekheeya pradesh mein ek apekshaakrut alp, kintu atyant ekasamaan, daab ka akhand katibandh hai. January maas mein yeh katibandh bhoomadhyarekha ke kuchh uttar ki or hai, parantu July maas mein ya to theek us rekha par hai ya thoda dakshin ki or. yeh alp-daab-katibandh prashaant tatha ushn mausam ka katibandh hai jo samudra par doldram ke naam se prasiddh hai. is poore katibandh ko ham bhoomadhyarekheeya alp-daab-katibandh kah sakte hain.

(kh) uposhn (sab-traupikl) deshon mein (lagbhag 30° dakshin akshaansh ke nikat) H chauda akhand adhik daab ka katibandh January aur July donon hi maason mein hota hai, parantu January maas mein Australia tatha dakshin Africa ke oopar yeh chhote chhote alpadaab kshetron dvaara thoda vichhinn ho jaata hai. yeh chauda katibandh uposhnavalayik adhidaab katibandh kahalaata hai jo donon golaardho mein saamaanya sanchaar ka ek sthaayi svaroop hai.

(g) uposhnavalayik adhidaab katibandh ke dakshin mein vaayudaab dakshin ki or baraabar girti jaati hai aur antaarkatika mahaadveep ke oopar nyoonatam ho jaati hai.

uttari golaardh mein nimnalikhit teen praathamik daabakshetron ka parichay milta hai:

(1) bhoomadhyarekheeya alpadaab katinbadh, jo donon golaardhon mein samaan roop se vidyamaan rahata hai.

(2) uposhnavalayik adhi-daab-katibandh is golaardh mein poornataya bhinn prakaar ka hai. January maas mein yeh samudron par lagbhag 25°-35° uttar mein rahata hai. parantu mahaadveepon ke oopar ooainche akshaanshon mein iska sambandh bahut adhik daab ki pranaaliyon se rahata hai. ye daabapranaaliyaaain lakshan mein ekdam bhinn hoti hain aur isliye uposhnavalayik adhi-daab-katibandh ko samudron tak hi seemit samajhna uchit hai.

(3) January maas ke nakshe par upottaradhruveeya (sab-aarkatik) alpadaab-katibandh spashtataya dikhaai deta hai. is katibandh mein do bade alpadaab kshetr aaisalaind tatha alooshiyn dveepon par hain, jo kramaanusaar uttaratam atalaantik mahaasaagar par tatha uttaratam paisifik mahaasaagar par vistrut hain. in donon kshetron ke beech mein dhruv par apekshataya adhik daab ka ek kshetr hai. greeshm ritu mein ye alpadaab bahut ksheen hote hain. alooshiyn kshetr to gaayab ho jaata hai. dhruvon par vaayudaab apekshaakrut adhik rahati hai. uposhnavalayik adhidaab katibandh tatha upadhruveeya alpadaab katibandh ki akhandata mein vichhinnata naveen tatha agyaat tatvon ke kaaran hoti hai jinka dakshini golaardh mein abhaav hai.

gaun sanchaar chaahe pratichkravaati hon ya chakravaati, unka lakshan yeh hai ki ek ya adhik samadaab rekhaaeain adhidaab keindron ya alpadaab keindron ko chaaron or se gherakar band kar deti hain. is prakaar adhidaab kshetr tatha alpadaab kshetr kramaanusaar vaayumandal ke bhaar ki adhikta athva nyoonata ke sthaaneeya kshetr hote hain. gaun sanchaar do prakaar ke hote hain : (1) pratyakshat: ushmeeya (tharmali direct) aur (2) gatik (daainaimik) athva pranodit (forsd). pratyakshat: ushmeeya adhidaab tatha alpadaab nichle vaayumandal ke kisi sthaanavishesh ke thanda ya garam hone se nirmit hote hain. gatik adhidaab tatha alpadaab donon hi saamaanya sanchaar ki vaayudhaaraaon ki paarasparik yaantrik (mikainikl) kriyaaon ke kaaran nirmit hote hain. pratyakshat: ushmeeya gaun sanchaaron mein paavas (monsoon) tatha ushnavalayik prabhanjan (hareeken) sanmmilit hain.

monsoon shabd ritusoochak arabi shabd se nikla hai aur aarambh mein arab samudra ke un pavanon ke liye iska vyavahaar kiya jaata tha jo lagbhag chhah maheene uttar-poorv se aur chhah maheene dakshin-pashchim se chalti hain. ab yeh shabd kuchh anya pavanon ke liye bhi laagoo ho gaya hai jo varsh ki vibhinn dishaaon mein pratikool dishaaon se deerghakaalik tatha niyamit roop se chalti hain. in pavanon ke chalne ka praathamik kaaran thal tatha samudri kshetron ke taapon ka ritujanit antar hai. ye pavan thalasameer tatha jalasameer ke sadrush hi hote hain parantu inki avadhi ek din ke bajaae ek varsh ki hoti hai aur ye seemit kshetron ke bajaae bahut vistrut kshetron par chalte hain. monsoon ko hindi mein paavas kehte hain.

bhoomadhyarekha ke sameep taap ke ritujanit parivartan saamaanyat: paavas ke vikaas ke liye bahut chhote hote hain. ooainche akshaanshon mein, jahaaain pachhuva pavan chalta hai aur dhruveeya pradeshon mein, thal aur samudra ke taap ki vibhinnata se bane vaataghat (kavind kaumponeint) pruthveevyaapi pavanasanchaaron ko keval thoda sa hi badalne mein samarth hote hain. aisi paristhiti mein paavas ke vikaas ke liye sabse adhik anukool pradesh ushnaavalaya ke sameep madhya akshaanshon mein hote hain. sthal ki or chalanevaale pavanon mein vidyamaan aardrata ki maatra ka tatha sthal ki rooparekha ka paavasavarsha par atyant prabhaav padta hai. vibhinn ghatnaaon ki uparyukt sangati ke kaaran paavas ka adhiktam vikaas poorv tatha dakshin Asia par hota hai aur in pradeshon ke bahut se bhaagon mein dakshin-pashchim se chalanevaale greeshm ritu ke vrushtimaan paavasapavan jalavaayu ke mahatvapoorn ang hain. paavasaparisthiti uttar Australia mein, pashchimi, dakshini tatha poorvi Africa ke bhaagon mein aur uttari Africa tatha chili ke bhaagon mein bhi utpann hoti hai, parantu bahut kam maatra mein.

Bhaarat mein paavas achaanak tatha naatakeeya roop se aata hai. iski utpatti dakshin bhaarateeya vyaapaarik pavanon se hoti hai. ye June maas ke aarambh mein bhoomadhyarekha ke aarapaar chalana aarambh kar dete hain aur mukhyat: rekhaansh 80° poorv ke tatha lagbhag rekhaansh 5° uttar par Bhaarat desh ki or mud jaate hain. June maas ke madhya mein Bhaarat ke pashchimi kinaare par pahuainchakar paavas dakshin pradesh ko paar kar leta hai aur fir bhaaratavarsh, barma tatha Bengal ki khaadi ke sab bhaagon mein pahuainch jaata hai. dakshin pradesh ke dakshini bhaagon ke atirikt, jahaaain pashchimi ghaaton ki pahaadiyon ki aad ke kaaran ye pavan pahuainch naheen paate, monsoon kaal mein Bhaarat ke sab bhaagon mein bhaari varsha hoti hai. yeh varsha lagbhag poornataya sanvahaneeya (kanavektiv) hoti hai. iski pragati ke liye mukhyat: bhootal ki tapan tatha usaki ooainchaai se vaashp ka jal mein roopaantarit hona niyantrit hota hai. bhoomitl ki uthaan ka prabhaav pashchimi ghaaton mein, khaasi ki pahaadiyon mein, araakaan ki chotiyon mein tatha himaalaya parvat par bhali bhaaainti dikhaai padta hai. in bhaagon mein atyadhik varsha hoti hai. kabhi kabhi gangaaghaati ki droni mein bahut der tak vistrut varsha hoti rahati hai. yeh lagaataar varsha praaya: un uthale avadaabon ke kaaran hoti hai jo mukhya paavasi alpadaab ki or pashchim disha mein mand gati se chalti hain. bhaarateeya paavas ki shakti bahut ghatati badhti rahati hai. jab paavas teevr hota hai to Bhaarat ke adhiktam bhaagon mein varsha ausat se bahut adhik ho jaati hai aur jab paavas halka hota hai to varsha nyoon hoti hai. paavas ka uttar ki or badhna himaalaya pahaad ke kaaran seemit ho jaata hai, parantu paavas ka pravaah barma, Thailand, indocheen tatha dakshin cheen mein bahut pravichhinn rahata hai. is praayadveep ke aksh ke nikat sthit ooainchi pahaadiyaaain (jo Bhaarat-yoonan-vaayumaarg par koobad ke naam se kukhyaat hai) ghane sanvahan baadalon se dhaki rahati hain aur yahaaain bahudha varsha hoti rahati hai.

paavas ke aaranbhakaal mein varsha ki maatra aur baaranbaarata mein bhaari uttaar chadhaav hote rahate hain jo bhaarateeya krushak jeevan ke liye atyant mahatvapoorn hain. isliye is desh mein saankhyikeeya deerghaparaas ritu poorvaanumaan (staitistikl lauङaareinj forakaasting) ke vikaas ki or adhik dhyaan diya gaya hai aur saankhyikeeya reetiyon ka bhaarateeya paavas ke alpakaalik parivrtanon ke sambandh mein upayog kiya ja raha hai. Bhaarat mein is prakaar se kiye hue ritu vishyak poorvaanumaan haal ke varsho mein paryaapt roop se theek siddh hue hain.

• aar.dablyoo. lauङaali : meetiorauloji, thyoratikl aind aplaayad (1944);
• H.si.vilet : deskriptiv meetiorauloji (1944)

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• Bhaarat ka mausam vibhaag (hindi mein)
• Bhaarat ka mausam vibhaag (puraana link)
• ki‍asaanon ke li‍ae krushi mausam salaah seva
• [http://metnet.imd.gov.in/imdrajbhasha/docs/3_Chennai_H_Sem.pdf mausam vigyaan ka vikaas, aadikaal se aadhunik kaal tak)
• Air Quality Meteorology - Online course that introduces the basic concepts of meteorology and air quality necessary to understand meteorological computer models. Written at a bachelor's degree level.
• The GLOBE Program - (Global Learning and Observations to Benefit the Environment) An international environmental science and education program that links students, teachers, and the scientific research community in an effort to learn more about the environment through student data collection and observation.
• Glossary of Meteorology - From the American Meteorological Society, an excellent reference of nomenclature, equations, and concepts for the more advanced reader.
• JetStream - An Online School for Weather - National Weather Service
• The Weather Guide - Weather Tutorials and News at About.com
• Meteorology Education and Training (MetEd) - The COMET Program
• The World Weather 2010 Project The University of Illinois at Urbana-Champaign
• NOAA Weather Navigator Plot and download archived data from thousands of worldwide weather stations
• Ogimet - online data from meteorological stations of the world, obtained through NOAA free services
• Solar Eclipse Meteorological Measurement