Nthawi zambiri mvula yamkuntho imagwirizanitsidwa ndi mvula yamphamvu, mphepo yamkuntho, kapena chimphepo. Izi sizowona kwenikweni: mvula yamkuntho si mphepo yamkuntho, koma ndi kayendedwe ka mphepo kudera linalake. Zotsatira zake, pakhoza kukhala mvula yambiri yachilimwe ndi chilala nthawi zina pachaka.
Nyuzipepala ya National Weather Service inanena kuti mphepo yamkuntho (kuchokera ku Arabic mawsim, kutanthauza “nyengo”) chifukwa cha kusiyana kwa kutentha kwa nthaka ndi nyanja. Dzuwa limatenthetsa nthaka ndi madzi mosiyana, ndipo mpweya umayamba "kukoka nkhondo" ndikugonjetsa mpweya wozizira, wonyowa wochokera m'nyanja. Kumapeto kwa nyengo ya monsoon, mphepo imabwerera m’mbuyo.
Mvula yamvula nthawi zambiri imabwera m'miyezi yachilimwe (April mpaka September) ikubweretsa mvula yambiri. Pafupifupi, pafupifupi 75% ya mvula yapachaka ku India komanso pafupifupi 50% kudera la North America (malinga ndi kafukufuku wa NOAA) imagwa m'nyengo yachilimwe. Monga tafotokozera pamwambapa, mvula yamkuntho imabweretsa mphepo yam'nyanja kumtunda.
Dry monsoons amapezeka mu October-April. Miyezi yowuma imabwera ku India kuchokera ku Mongolia ndi kumpoto chakumadzulo kwa China. Iwo ali amphamvu kwambiri kuposa anzawo a chilimwe. Edward Guinan, pulofesa wa sayansi ya zakuthambo ndi zakuthambo, ananena kuti mvula ya m’nyengo yachisanu imayamba pamene “dziko limazizira kwambiri kuposa madzi ndipo mphamvu yamphamvu imachuluka padziko, n’kuchititsa kuti mpweya wa panyanja utuluke.” Chilala chikubwera.
Chaka chilichonse ma monsoons amachita mosiyana, kubweretsa mvula yopepuka kapena yamphamvu, komanso mphepo za liwiro losiyanasiyana. Indian Institute of Tropical Meteorology yapanga zambiri zosonyeza mvula zapachaka zaku India pazaka 145 zapitazi. Kuchuluka kwa ma monsoons, zimakhala, zimasiyana zaka 30-40. Zomwe zakhala zikuchitika kwa nthawi yayitali zikuwonetsa kuti pali nthawi za mvula yofooka, imodzi mwa izi idayamba mu 1970, ndipo pali yamphamvu. Zolemba zamakono za 2016 zidawonetsa kuti kuyambira pa Juni 1 mpaka Seputembala 30, mvula idafika 97,3% yanthawi zonse.
Mvula yamphamvu kwambiri inagwa ku Cherrapunji, m’chigawo cha Meghalaya ku India, pakati pa 1860 ndi 1861, pamene mvula ya 26 mm inagwa m’derali. Dera lomwe lili ndi chiwopsezo chachikulu kwambiri pachaka (zowonera zidachitika zaka 470) lilinso m'chigawo cha Meghalaya, komwe pafupifupi 10 mm yamvula idagwa.
Malo omwe ma monsoons amapezeka ndi madera otentha (kuyambira 0 mpaka 23,5 madigiri kumpoto ndi kummwera kwa latitude) ndi subtropics (pakati pa 23,5 ndi 35 madigiri kumpoto ndi kummwera). Ma monsoons amphamvu kwambiri amawonedwa, monga lamulo, ku India ndi South Asia, Australia ndi Malaysia. Monsoons amapezeka kumadera akumwera kwa North America, ku Central America, kumpoto kwa South America, komanso ku West Africa.
Monsoon amachita mbali yofunika kwambiri m'madera ambiri padziko lapansi. Ulimi m'mayiko ngati India umadalira kwambiri nyengo yamvula. Malinga ndi National Geographic, zopangira magetsi opangira magetsi pamadzi zimakonzanso ntchito yawo malinga ndi nyengo yamvula.
Nyengo zamvula zapadziko lapansi zikangogwa mvula yochepa, mbewu sizimapeza chinyezi chokwanira ndipo ndalama zaulimi zimachepa. Kupanga magetsi kukuchepa, zomwe zimangokwanira zosowa zamakampani akuluakulu, magetsi amakhala okwera mtengo ndipo amakhala osafikirika kwa mabanja osauka. Chifukwa cha kusowa kwa zakudya zomwe zimagulitsidwa, katundu wochokera kumayiko ena akuwonjezeka.
Pa nthawi ya mvula yambiri, kusefukira kwa madzi kumatheka, zomwe zimawononga osati mbewu zokha, komanso kwa anthu ndi nyama. Mvula yochuluka imapangitsa kuti matenda afalikire: kolera, malungo, komanso matenda a m'mimba ndi maso. Ambiri mwa matendawa amafalitsidwa ndi madzi, ndipo malo odzaza madzi olemedwa sangakwanitse kuthira madzi akumwa ndi zofunika zapakhomo.
Dongosolo la ku North America monsoon limayambitsanso kuyamba kwa nyengo yamoto kumwera chakumadzulo kwa United States ndi kumpoto kwa Mexico, lipoti la NOAA likuti, chifukwa cha kuwonjezeka kwa mphezi chifukwa cha kusintha kwa kutentha ndi kutentha. M'madera ena, zikwi makumi zikwi za mphezi zimachitika usiku umodzi, zomwe zimayambitsa moto, kulephera kwa magetsi komanso kuvulala koopsa kwa anthu.
Gulu la asayansi ochokera ku Malaysia likuchenjeza kuti chifukwa cha kutentha kwa dziko, kuwonjezeka kwa mvula m'nyengo ya chilimwe kuyenera kuyembekezera zaka 50-100 zikubwerazi. Mipweya yotentha yotentha, monga carbon dioxide, imathandiza kusunga chinyezi chochuluka mumpweya, chomwe chimagwa m’madera amene madzi osefukira kale amagwa. M’nyengo yamvula yamvula, nthaka idzauma kwambiri chifukwa cha kutentha kwa mpweya.
Pakanthawi kochepa, mvula m'nyengo yachilimwe imatha kusintha chifukwa cha kuipitsidwa kwa mpweya. El Niño (kusinthasintha kwa kutentha pamwamba pa nyanja ya Pacific) imakhudzanso mvula yamkuntho ya ku India m’kanthawi kochepa komanso kotalika, akutero ofufuza a pa yunivesite ya Colorado ku Boulder.
Zinthu zambiri zimatha kuyambitsa ma monsoon. Asayansi akuchita zonse zomwe angathe kuti adziŵe mvula yamtsogolo ndi mphepo - pamene tikudziwa zambiri za khalidwe la monsoon, ntchito yokonzekera idzayamba mwamsanga.
Pamene pafupifupi theka la anthu aku India amalembedwa ntchito zaulimi ndipo agronomy amatenga pafupifupi 18% ya GDP ya India, nthawi ya monsoon ndi mvula imatha kukhala yovuta kwambiri. Koma, kafukufuku wopangidwa ndi asayansi amatha kumasulira vutoli kukhala yankho lake.