Ukuqapha isimo somgodi kusendlalelo se-ozone, ukuhlushwa kwe-ozone ku-stratosphere kukalwe iminyaka engamashumi amathathu ngesathelayithi. Ngemuva kwalesi sikhathi sokulinganisa, ekugcineni kutholakale izimpawu zokutholakala komhlaba ungqimba lwe-ozone, sibonga imizamo eyenziwe emhlabeni jikelele ukunqanda ukusetshenziswa kwezinto eziyichithayo.
Ingabe imiphumela emihle oyithole mayelana nobukhulu besendlalelo se-ozone?
Indima yesendlalelo se-ozone
Isendlalelo se-ozone simane siyindawo ye-stratosphere lapho ukugxila kwale gesi kuphakeme kakhulu. Lo gesi usebenza njengesivikelo emisebeni yelanga eyi-ultraviolet eyingozi. Ngenxa yalokho, Asishisi isikhumba sethu ngokuzichaya elangeni, izitshalo zingaphila futhi zenze ifotosinthesize, njll. Ukuqonda ukubaluleka kongqimba lwe-ozone kubalulekile ekuqondeni ukululama kwalo, njengoba isimo salo siyithinta ngokuqondile impilo yabantu neyemvelo.
Ngakho-ke, ungqimba lwe-ozone olunempilo lubalulekile ekuphileni njengoba sazi ukuthi luchume emhlabeni. Intuthuko yezobuchwepheshe iholela ekukhishweni okukhulu kwamagesi abhubhisa ungqimba lwe-ozone, njengama-chlorofluorocarbon. La magesi asabela nezinhlayiya ze-ozone kuyi-stratosphere, azibhubhise. Ngenxa yabo abadumile imbobo yesendlalelo se-ozone, okuye kwabangela ukukhathazeka okukhulu emphakathini wesayensi.
Imbobo kusendlalelo se-ozone akuyona imbobo ngokwayo, ngoba uma kunjalo, kungaba yingozi kakhulu emhlabeni, njengoba itholakala e-Antarctica futhi ingavumela ukuncibilika ngokushesha kweqhwa laleli zwekazi. Lo "mgodi" umane wehla ekugxileni kwalolu ungqimba oluzungeze i-Antarctica.
Lapho ukuncipha kwe-ozone kuvumela imisebe eyingozi ye-ultraviolet evela elangeni ukuba idlule, ukuchayeka kule misebe kuyakhula, kubangele umdlavuza wesikhumba, ulwelwesi lwamabala, nokuphazamiseka kwesimiso somzimba sokuzivikela ezifweni. Ziphinde zithinte izilwane, izitshalo, ngisho ne-phytoplankton encane, engaphazamisa uchungechunge lokudla futhi ithinte izinhlobonhlobo zezinto eziphilayo.
Ukubuyiselwa kwe-ozone
I-ozone, etholakala ku-stratosphere, itholakala cishe ngamakhilomitha ayi-11-50 ngenhla komhlaba yaqala ukwehla ngeminyaka yama-70s yekhulu elidlule. Ukwehliswa okuphawuleka kakhulu kusukela lapho ungqimba lwe-ozone luphakathi kuka-4 no-8% eminyakeni eyishumi. Ukuze uqonde umthelela walezi zinguquko, kubalulekile ukubonisana nolwazi mayelana ne ukubhujiswa kongqimba lwe-ozone nokuthi lokhu kube nomthelela kanjani ekubuyiselweni kongqimba lwe-ozone.
Ngenxa yezivumelwano zamazwe ngamazwe, njenge-Montreal Protocol, evimbela ukusetshenziswa nokunciphisa izinto ezicekela phansi ungqimba lwe-ozone, ukwehla kwesimo kumisiwe. Le mizamo yomhlaba ibalulekile ekuqinisekiseni ukululama kwe-ozone emashumini eminyaka ezayo.
Iziphuphutheki eziqhubeka nokuqapha nokuqapha ukuhlushwa kwe-ozone kuzo zonke izindawo zomhlaba zikwazile ukuthola izimpawu zokuqala zokululama. AmaSatellites anikela ngezilinganiso ezanele, yize umkhawulo wawo wesikhashana uwavimba ekwenzeni ama-panorama amaningi wokuhlushwa kwe-ozone. Ososayensi besimo sezulu balinganisela ukuthi ukufundwa kwe-satellite ozone kuzothatha iminyaka engama-30 noma ngaphezulu futhi ayadingeka ukuze akwazi ukuhlaziya ukuthambekela kokugxila kwe-ozone ngokunemba okukhulu.
Ngokuya ngesizini nomsebenzi welanga, ukugxila kwe-ozone akuhlali kuzinzile unyaka wonke. Ngakho-ke, kubalulekile ukuhlaziya ukuthambekela kokugxilisa ingqondo phakathi neminyaka futhi hhayi nje ukugxila okuqondile. Ngakho-ke, izinyathelo ziyadingeka amashumi eminyaka ukuze kuqinisekiswe ukuthi abantu bayayibangela imbobo yesendlalelo se-ozone uqale ukululama.
Ukuphendula le nkinga, ososayensi abavela ku- I-ESA Initiative Change Initiative Zivumelanisa izilinganiso ezivela kumasathelayithi ahlukahlukene ukuthola umbono wesikhathi eside wokuhlukahluka kwe-ozone.
“Ngokuhlanganisa imininingwane evela ku-Climate Change Initiative nedatha evela ku-NASA, sibona ngokusobala izitayela ezingezinhle ku-ozone yomkhathi ongaphezulu ngaphambi kuka-1997 nemikhuba emihle ngemuva kwalolo suku. Amathrendi e-stratosphere ephezulu ngaphesheya kwezindawo ezishisayo abalulekile ngokwezibalo futhi aqala ukuvuselelwa kwe-ozone, "usho kanje. UViktoria Sofieva, Senior Research Scientist eFinland Meteorological Institute.
Ngenxa yalokhu, manje sesingakwazi ukuqonda inkambiso yongqimba lwe-ozone, olubonakala lusendleleni yokululama ngemva kweminyaka yokonakala.
