Wake waba sebhishi ngosuku olunelanga? Ngosuku olunelanga, kuhlale kunomoya ovunguzayo usuka olwandle uye ezweni elisebhishi. Kungani kuhlale kunomoya ogwini futhi kungani umoya wolwandle (umoya ovunguzayo usuka olwandle uye ezweni) uvela emini, kanye nomoya womhlaba (umoya ovunguzayo usuka ezweni uye olwandle) uvela ebusuku? Kungani amafu ehlela ezintabeni ngesikhathi semvula? Kungani umoya uzwakala upholile? Izimpendulo zale mibuzo zihlobene nokushisa okuqondile komhlaba nolwandle, ukwanda, ukuminyana kanye nokudluliselwa kokushisa nge-convection (ukudluliselwa kokushisa). Ngokuqonda lesi sihloko kahle nangokufanele, ungaphendula imibuzo engenhla kanye neminye imibuzo ongase uyibuze kamuva.
Ukudluliselwa kokushisa ngokuqhutshwa komoya ngokuvamile kwenzeka ezintweni eziqinile noma kusukela ezintweni eziqinile kuya ezintweni eziwuketshezi (izinto eziwuketshezi kuya ezintweni eziqinile) noma kusukela ezintweni eziqinile kuya ezintweni zegesi (izinto zegesi kuya ezintweni eziqinile). ukudluliselwa kokushisa nge-convection ngokuvamile kwenzeka koketshezi (isib. amanzi) kanye namagesi (isib. umoya).
Ukudluliselwa kokushisa kwe-Convection kuwukudluliselwa kokushisa okuhambisana nokuhamba kwezinto. Ukuze uqonde kangcono ukudluliselwa kokushisa kwe-convection, cabanga ngecala, njengamanzi afudunyezwa ngomlilo. Lapho amanzi esitsheni efudunyezwa ngomlilo, ukushisa kuhamba kusuka emlilweni (izinga lokushisa eliphezulu) kuya esitsheni (izinga lokushisa eliphansi) ngokuqhutshwa kanye nemisebe. Ukushisa bese kuhamba kusuka esitsheni (izinga lokushisa eliphakeme) kuya emanzini aseduze nesitsha (izinga lokushisa eliphansi) ngokuqhutshwa. Okwengeziwe ukushisa imbangela shu Amanzi aseduze nesitsha ayanda. Ukwenyuka kwezinga lokushisa kwamanzi kubangela ukuthi amanzi ande noma umthamo wamanzi ukhuphuke. Ngenxa yokuthi umthamo wamanzi uyanda, ukuminyana Amanzi ayancipha. Amanzi aseduze nephansi kwesitsha anokushisa okuphezulu kunamanzi angaphezulu kwaso. Ngamanye amazwi, amanzi aseduze nephansi kwesitsha anomthamo omkhulu nobuningi obuncane, kuyilapho amanzi angaphezulu kwawo enomthamo omncane nobuningi obukhulu. Umehluko wobuningi ubangela ukuthi amanzi ebusweni besitsha, esinobukhulu obukhulu, ahambe phansi kanti amanzi aseduze nephansi lesitsha, esinobukhulu obuncane, ahambe phezulu. Le nqubo yenzeka njalo kuze kube yilapho wonke amanzi angaphakathi enokushisa okufanayo (Uma umfutho womoya ungumoya owodwa, amanzi esitsheni azophuma, okubizwa ngokuthi abile ekushiseni okungu-100 oC).
Ukwenzeka kwemimoya yasezweni kanye nemimoya yasolwandle kuhilela nokudluliselwa kokushisa ngokuqhutshwa kanye nokuguqulwa komoya. Ukushisa okuqondile komhlaba (ukushisa okuqondile kwento eqinile) kuphansi kunokwamanzi olwandle, ngakho-ke umhlaba ushisa ngokushesha uma ubhekene nokukhanya kwelanga futhi uphola ngokushesha ebusuku. Izwe lishisa ngokushesha, lifudumeza umoya ongaphezulu kwalo (ukudluliselwa kokushisa kusuka ezweni kuya emoyeni ngokuqhutshwa komoya). Izinga lokushisa lomoya elithola ukushisa okwengeziwe liyakhula futhi umoya uyakhula. Ngenxa yalokho, ubuningi bomoya buyancipha. Ngokuphambene nalokho, izinga lokushisa lamanzi olwandle lipholile, ngakho umoya ongaphezu kobuso bolwandle nawo upholile, uma kuqhathaniswa nomoya ongaphezu kobuso bomhlaba. Umoya osezingeni lolwandle ubanda kakhulu, ngakho ubuningi bawo bukhulu kakhulu. Lo mehluko wobuningi bomoya ubangela ukuthi umoya osezingeni lolwandle uye ezweni, usunduze umoya ongaphezu kwawo phezulu. Uma uqhelelene nobuso boMhlaba, kukhiqizwa umoya omncane ngenxa yokwehla kwamandla adonsela phansi oMhlaba. Ngenxa yokuthi inani lomoya liyancipha, ingcindezi yomoya nayo iyancipha. Umoya oshisayo ngaphezu komhlaba ohambela phezulu uyaphola ngoba uma uqhelelene nobuso boMhlaba, umfutho womoya omncane ukhona. Umoya obandayo bese wehla futhi, hhayi ebusweni bomhlaba kodwa ebusweni bolwandle, olunezinga lokushisa elipholile. Le nqubo yenzeka njalo, idala ukugeleza komoya osuka olwandle uye ezweni. Ngamafuphi, umoya oseduze nobuso bolwandle uya ezweni, umoya oseduze nobuso bomhlaba uya phezulu, kanti umoya ongaphezulu kwawo uya olwandle.
Kungani intuthu ihlala ikhuphukela phezulu?
Intuthu ikhuphuka ngoba izinga lokushisa layo liphakeme kunomoya ozungezile. Ngenxa yokuthi izinga lokushisa lentuthu liphakeme, ivolumu yayo iyanda futhi ubuningi bayo buyancipha. Ubuningi obuphansi bentuthu bubangela ukucindezeleka kwentuthu okuphansi uma kuqhathaniswa nokucindezela komoya ozungezile. Umoya ozungezile usunduzela intuthu phezulu.
Kungani amafu ehla ngesikhathi semvula? Ngesikhathi semvula, amafu aqukethe umhwamuko wamanzi omningi, okwandisa ubuningi bawo. Amafu aqukethe umhwamuko wamanzi omningi futhi anobukhulu obukhulu ahla aye endaweni lapho umoya ozungezile unobukhulu obufanayo nobefu.
