I-ozone wuhlobo lomoya-mpilo otholakala ku-stratosphere, cishe amakhilomitha ayi-12-50 ukusuka emhlabeni. Ukuhlungwa okuphezulu kakhulu kwalesi sakhi kukude ngamakhilomitha angama-23 ukusuka phezulu. I-Ozone yatholwa ngo-1873 ngusosayensi waseJalimane uSchönbein. Ngokulandelayo, lokhu kuguqulwa komoya-mpilo kwatholakala ebusweni nasezingxenyeni ezingaphezulu zomkhathi. Ngokuvamile, i-ozone yakhiwa ama-molecule e-oxygen e-triatomic. Ngaphansi kwezimo ezijwayelekile igesi eluhlaza okwesibhakabhaka enephunga lesici. Ngaphansi kwezici ezahlukahlukene, i-ozone iphenduka uketshezi lwe-indigo. Lapho iba lukhuni, ithatha umbala ohlaza okwesibhakabhaka ojulile.
Inani lesendlalelo se-ozone lilele eqinisweni lokuthi lisebenza njengohlobo lwesihlungi, lumunca inani elithile lemisebe ye-ultraviolet. Kuvikela i-biosphere nabantu kusuka elangeni eliqondile.
Izimbangela zokuncipha kwe-ozone
Emakhulwini amaningi eminyaka abantu bebengazi ukuthi kukhona i-ozone, kepha umsebenzi wabo ube nomthelela omubi esimweni somoya. Okwamanje, ososayensi bakhuluma ngenkinga efana nezimbobo ze-ozone. Ukuncipha kokuguqulwa komoya-mpilo kwenzeka ngezizathu ezahlukahlukene:
- sethula amarokhethi neziphuphutheki emkhathini;
- ukusebenza kokuthuthwa komoya endaweni ephakeme ngamakhilomitha ayi-12-16;
- ukukhishwa kwama-freons emoyeni.
Iziphepheli ezinkulu ze-ozone
Izitha ezinkulu zesendlalelo sokuguqulwa komoya-mpilo yizinhlanganisela ze-hydrogen ne-chlorine. Lokhu kungenxa yokubola kwama-freon, asetshenziswa njengezifafazi. Ezingeni elithile lokushisa, bayakwazi ukubilisa nokukhuphula ivolumu, okubalulekile ekwakhiweni kwama-aerosol ahlukahlukene. Ama-Freon ajwayele ukusetshenziselwa okokuqandisa imishini, amafriji nezindawo zokupholisa. Lapho ama-freons enyukela emoyeni, i-chlorine iyasuswa ngaphansi kwezimo zomkhathi, zona eziguqula i-ozone ibe yi-oxygen.
Inkinga yokwehla kwe-ozone yatholwa kudala, kepha ngeminyaka yama-1980, ososayensi base beyizwisile inhlabamkhosi. Uma i-ozone incishiswa ngokuphawulekayo emkhathini, umhlaba uzolahlekelwa ukushisa okujwayelekile futhi uyeke ukuphola. Ngenxa yalokho, kwasayinwa inqwaba yamadokhumenti nezivumelwano emazweni ahlukahlukene ukunciphisa ukukhiqizwa kwama-freon. Ngaphezu kwalokho, kwasungulwa indawo yama-freon - i-propane-butane. Ngokuya ngemingcele yezobuchwepheshe, le nto inokusebenza okuphezulu, ingasetshenziswa lapho kusetshenziswa khona ama-freon.
Namuhla, inkinga yokuncipha kongqimba lwe-ozone iphuthuma kakhulu. Ngaphandle kwalokhu, ukusetshenziswa kobuchwepheshe obunokusetshenziswa kwama-freon kuyaqhubeka. Okwamanje, abantu bacabanga ukuthi bangalinciphisa kanjani inani lokukhishwa kwe-freon, bafuna ababambele ukugcina nokubuyisela ungqimba lwe-ozone.
Izindlela zokulawula
Kusukela ngo-1985, kuye kwathathwa izinyathelo zokuvikela ungqimba lwe-ozone. Isinyathelo sokuqala ukwethulwa kwemikhawulo ekukhishweni kwama-freon. Ngaphezu kwalokho, uhulumeni wagunyaza iSivumelwano saseVienna, ukuhlinzekwa kwaso okuhloswe ngakho ukuvikela ungqimba lwe-ozone futhi kunamaphuzu alandelayo:
- abamele amazwe ahlukene bamukela isivumelwano sokubambisana maqondana nokufundwa kwezinqubo nezinto ezithinta ungqimba lwe-ozone futhi zivusa ushintsho lwazo;
- ukuqapha okuhlelekile kwesimo sezingqimba ze-ozone;
- ukwakhiwa kobuchwepheshe nezinto ezihlukile ezisiza ukunciphisa umonakalo odalekile;
- ukubambisana ezindaweni ezahlukahlukene zokuthuthukiswa kwezinyathelo nokusetshenziswa kwazo, kanye nokulawulwa kwemisebenzi evusa ukuvela kwemigodi ye-ozone;
- ukudluliswa kobuchwepheshe nolwazi olutholakele.
Emashumini eminyaka adlule, kusayiniwe izivumelwano, okuya ngokuthi kuncishiswe ukukhiqizwa kwama-fluorochlorocarbon, futhi kwezinye izimo kumiswe ngokuphelele.
Okuyinkinga kakhulu ukusetshenziswa kwemikhiqizo evumelana ne-ozone ekukhiqizeni imishini yesiqandisi. Ngalesi sikhathi, kwaqala "inkinga ye-freon" yangempela. Ngaphezu kwalokho, intuthuko idinga ukutshalwa kwezimali okuphawulekayo, obekungacasula osomabhizinisi. Ngenhlanhla, kwatholakala isixazululo futhi abenzi esikhundleni sama-freon baqala ukusebenzisa ezinye izinto kuma-aerosols (i-hydrocarbon propellant efana ne-butane noma i-propane). Namuhla, noma kunjalo, kujwayelekile ukusebenzisa ukufakwa okwaziyo ukusebenzisa ukusabela kwamakhemikhali okuphela kwesikhathi okufaka ukushisa.
Kungenzeka futhi ukuhlanza umkhathi kokuqukethwe kwama-freon (ngokusho kososayensi be-physics) ngosizo lweyunithi yamandla we-NPP, amandla ayo okufanele okungenani abe yi-10 GW. Lo mklamo uzosebenza njengomthombo omuhle kakhulu wamandla. Ngemuva kwakho konke, kuyaziwa ukuthi iLanga liyakwazi ukukhiqiza cishe amathani ama-5-6 we-ozone ngomzuzwana owodwa nje. Ngokwandisa le nkomba ngosizo lwamayunithi kagesi, kungenzeka ukufeza ibhalansi phakathi kokubhujiswa nokukhiqizwa kwe-ozone.
Ososayensi abaningi bakubona kukufanele ukudala "ifektri ye-ozone" ezothuthukisa isimo songqimba lwe-ozone.
Ngaphezu kwale phrojekthi, kuneminye eminingi, kufaka phakathi ukukhiqizwa kwe-ozone ngokuzenzela ku-stratosphere noma ukukhiqizwa kwe-ozone emkhathini. Okubi kakhulu kuyo yonke imibono neziphakamiso yizindleko zabo eziphakeme. Ukulahleka okukhulu kwezezimali kudonsela emuva amaphrojekthi ngemuva kanti okunye kwawo kuhlala kungagcwaliseki.
