Muva nje, kukhulunywa kakhulu ngokuthi amazinga okushisa azoba njani ngo-2017. Kuthiwa futhi neminyaka ka-2016 no-2014 beyikhona ezishisayo kakhulu kusukela amazinga okushisa aqoshwa nokuthi kulinganiselwa ukuthi u-2017 nawo uzobe ushisa kakhulu, yize kungewona oshisayo.
Abantu abaningi bazozibuza ukuthi izazi zezulu zikwazi kanjani ukubikezela la mazinga okushisa uma zingakafiki. Wazi kanjani amazinga okushisa azoba ngo-2017 uma unyaka usanda kuqala?
Iminyaka efudumele kakhulu
Njengoba kunamarekhodi okushisa ngonyaka we-1880, iminyaka eyi-16 yale nkulungwane yesibili, aphakeme kakhulu. Ngonyaka odlule, bekungunyaka wesithathu kulandelana lapho kufinyelelwe khona irekhodi elisha lonyaka lokushisa komhlaba.
Impikiswano ngokubikezelwa kwesimo sezulu ivela kwizimo zezulu. Ngoba, ngaphandle kwamazinga okushisa aphakeme ngokungajwayelekile ake aqoshwa, kusekhona ukungabaza ngemvelaphi ye-anthropogenic yamazinga okushisa aphezulu nokushisa komhlaba. Umsuka wale mpikiswano uvela ukwehluleka kwezazi zezulu ukubikezela kahle isimo sezulu ezinsukwini ezintathu noma ezine. Bakuthatha lokhu njengobufakazi bokuthi ososayensi abakwazi ukubikezela isimo sezulu somhlaba eminyakeni embalwa noma amashumi eminyaka.
Uma kunjalo, kungani ososayensi beqiniseka ukuthi bangakwazi ukubikezela amazinga okushisa angaphezu kwesilinganiso kusasele izinyanga, futhi ukubikezela kwesimo sezulu kuhluke kanjani ekubikezelweni kwesimo sezulu?
Ukunyakaza okunomkhathi
Imvamisa, ukubikezela isimo sezulu ezinsukwini ezimbalwa ngaphambili, ukuvela kwe amaphethini wokucindezela ezinhlelweni zasemkhathini. Yize isibikezelo sezulu kusasele amasonto amabili sithuthuke kakhulu, ngoba izinhlelo zasemkhathini azihlali isikhathi eside, azinembe kangako.
Uma kukhulunywa ngokuqagela ukwakheka kwezingcindezi eziphansi, kuletha ubunzima, ngoba ukunyakaza okungamakhilomitha angama-75 kuphela empumalanga noma entshonalanga maqondana nomzila obikezelwe kungasho umehluko phakathi kwesiphepho sezulu, isivunguvungu nemvula noma i-alamu engamanga. Okufanayo kwenzeka ngeziphepho zasehlobo nokubikezela kwemvula.
Noma kunjalo, lokhu akusho lokho akufanele sincike ezixwayisweni ezinamandla zesiphepho kanye nezibikezelo zezulu.
Ukubikezela kwesimo sezulu
Ngokungafani nezibikezelo ezisuselwa ezinhlelweni zesimo sezulu, ukubikezela kwesimo sezulu kwamazinga okushisa nemvula kusebenzisa idatha ehluke ngokuphelele.
Ukubikezela lezi zinto eziguquguqukayo zesimo sezulu kusasele izinyanga, iminyaka, noma amashumi eminyaka ngaphambili, zisuselwa ekwahlukaneni kwezilwandle, ukwehluka kwelanga, ukuqhuma kwentaba-mlilo, futhi-ke, nokwanda kokuhlushwa kwamagesi abamba ukushisa emkhathini. Lokhu kuguquka kuguquka futhi kuguquke ezinyangeni naseminyakeni ngokungafani nezinhlelo zasemkhathini ezingashintsha ngendaba yamahora noma izinsuku.
Isici esibalulekile esihluka kusuka ezinyangeni ezimbalwa kuye onyakeni yisimo se I-El Niño. Ukufudumala kwezikhathi ezithile kwamazinga okushisa olwandle kuyo yonke iPacific eshisayo. Le ndlela yokufudumala kolwandle kanye nemiphumela ehambisana nayo emoyeni inethonya elinamandla ngaphezu kwezindawo ezishisayo ezingafakwa ekubikezelweni kwesimo sezulu.
Izici zomuntu nezemvelo
Ngaphezu kwemiphumela yolwandle nemizimba yamanzi, ezinye izinto zemvelo ezifana nokuqhuma kwentaba-mlilo ziyaziwa ukuthi zithinta izinga lokushisa komhlaba. Kepha kufanele kushiwo ukuthi, kuze kube manje, ukwanda okukhulu kakhulu kwamazinga okushisa omhlaba kungenxa ye- ukwanda kokuhlushwa kwamagesi abamba ukushisa (GHG) ebangelwe ngabantu kanye nenguquko yezimboni.
Ngakho-ke, ukuqagela kokufudumeza esikalini sesikhathi esibanzi (amashumi eminyaka amaningi noma ngaphezulu) kusekelwe ekulingisweni kwamamodeli wesimo sezulu kanye nolwazi lwethu lokuthi uhlelo lwesimo sezulu lubucayi kangakanani ekukhuleni kwesikhathi esizayo kokugxila komkhathi we-GHG. Lezi zinhlobo zibonisa ukuthi ukufudumala kwembulunga esikhathini esizayo esingekude kakhulu kuzolawulwa ngamazinga akhuphukile e-GHG uma kuqhathaniswa nokwanda kwamazinga okushisa emvelo noma ngobuningi bolwandle noma ukuqhuma kwentaba-mlilo.