Sekungamashumi eminyaka manje bekhuluma ncibilika ezigxotsheni kubangelwa ukufudumala kwembulunga yonke. Izinga lokushisa eliphakathi komhlaba likhuphukela ezingeni lokuthi lidala ukuthi amakhemikhali apholile aphule futhi ancibilike. Ukuguquka kwesimo sezulu kungenye yemiphumela esheshayo yokwanda komphumela wokushisa. Imininingwane ekule ncibiliko iyesabeka impela ngoba kungabonakala ukuthi inqubo ishesha ngokwengeziwe.
Kulesi sihloko sizokutshela konke odinga ukukwazi ngokuncibilika kwezigxobo.
Kusho ukuthini ukuncibilika kwezigxobo
Uma sithi kunokuncibilika kwezigxobo kusho ukuthi izingqimba zeqhwa ezigxotsheni ziyancibilika. Ukulahleka kweqhwa uwoyela ojika amanzi abe yisimo esiwuketshezi kubangela ukwanda kwamazinga olwandle nezilwandle. Kumele kukhunjulwe ukuthi ukuqandisa nokuncibilika kuyinqubo engokwemvelo ngoba umhlaba unezinkathi ezahlukahlukene zokugodola nokufudumala. Kodwa-ke, esikwesabayo akukhona ukuthi kukhona ukuncibilika ngenxa yemijikelezo yemvelo yomhlaba wethu, kepha a Inqubo esheshisiwe ngenxa yezenzo zomuntu nemisebenzi.
Inkinga ukuthi ukuncibilika kweqhwa kwenzeka ngesivinini esisheshayo kunalokho okwenzeke kuwo wonke umlando kumjikelezo we-glaciation nokufudumala kweplanethi yethu. Lokhu kungenxa yomsebenzi omkhulu womuntu odala ukukhishwa kwegesi ebamba ukushisa okwazi ukugcina ukushisa emkhathini. Njengoba kunqwabelana ukushisa, amazinga okushisa aphakathi nendawo ayakhuphuka futhi kubangela ukuncibilika kwamakepisi we-polar.
Lokhu kuncibilika kusinikeza ngokwemvelo futhi kufanele kubonakale njengenkinga enkulu futhi ephuthumayo kubantu nakubo bonke abanye abantu abahlala emhlabeni.
Ukushisa kwe-Antarctic
Amanzi aphenduke iqhwa akhona e-Antarctica afudumala ngokushesha kunesilinganiso somhlaba jikelele. Siyazi ukuthi iplanethi yonke iyafudumala, kepha iyafudumala yonke indawo. Indawo yase-Antarctic noma iSouth Pole ishisa kakhulu kunezinga lonke ngenxa yokusatshalaliswa kwebhande elihambayo. Ibhande lokuhambisa ukuthi ukufuduka komoya okuhambisa izindimbane zomoya kusuka e-Equator kuya ezigxotsheni. Uma lezi zindimbane zomoya ziphethe amagesi abamba ukushisa ngaphakathi, ziqala ukugxila kakhulu endaweni yezigxobo. Lokhu kubangela ukuthi kube khona amagesi amaningi abamba ukushisa ezindaweni ezihlala kuzo, yize zisikhipha ngqo lapho.
I-Antarctica yandisa izinga lokushisa elijwayelekile ngezinga elingu-0.17 degrees Celsius kanti kokunye lenza isilinganiso esingu-0.1 degrees ngonyaka. Kodwa-ke, sibona ukuncibilika okujwayelekile emhlabeni wonke. Ngenxa yokuncibilika kwaleli qhwa, ulwandle lukhuphuka luzungeze umhlaba.
Kunemininingwane ethile ekhombisa ukwanda kweqhwa e-Antarctica. Kungabonakala njengokuxakayo ngandlela thile yize kwenzeka into ebanzi yokuncibilikisa. Sekukonke, iqhwa lolwandle lehlile yize iqhwa lase-Antarctic lenyukile. Lokhu ubekwenza njalo kusukela ngo-1979 futhi kufanele kungezwe ukuthi iGreenland nazo zonke izinguzunga zeqhwa emhlabeni nazo zalahleka. Ngakho-ke, kungashiwo ngokuqiniseka okuphelele ukuthi umhlaba uphelelwa amaqhwa eqhwa ngokuxhuma nemingcele.
Lokhu kulahleka okubanzi kwesembozo seqhwa lomhlaba kudala ukuthi ubuso bubonakalise amandla elanga amancane. Lokhu kwaziwa njenge-albedo. I-Albedo yikhono lomhlaba ukuthi likwazi ukubuyisa ingxenye yesigameko imisebe yelanga ebusweni ibuyele emkhathini. Iqiniso lokuthi umhlaba une-albedo ephansi kwenza ukufudumala kwembulunga yonke kube namandla kakhulu futhi, ngakho-ke, inqubo ibuyiselwa emuva ngendlela esheshayo. Ngakho-ke, ukuncibilika kwenzeka ngejubane eliphakeme. Kumele kushiwo ukuthi lokhu kuthinta izinga lolwandle, kubangele ukuthi likhuphuke ngokushesha okukhulu futhi kakhulu.
Naphezu kwayo yonke imininingwane eqhathaniswa nososayensi, kunobufakazi obusobala bokuthi akukhona nje kuphela ukuthi ukufudumala kwembulunga yonke kukhona kodwa kuyashesha ezikhathini zamuva. Eminye imithombo yezindaba iyaqhubeka nokubukela phansi imiphumela yokuguquguquka kwesimo sezulu ukugxila kwezinye izici.
Iqhwa lase-Antarctica lenyuke ngo-2012
Lokhu kuzwakala kuyindida ngandlela thile ukuthi kuneqhwa lasolwandle lase-Antarctic elingaphezulu. Ososayensi bakholelwa ukuthi imbangela yalesi simo umoya. Kunezindlela ezehlukene eqhweni lasolwandle ezixhumene kakhulu nemimoya yendawo. Kungenxa yokuthi amandla aguqukayo emimoya ebandayo yiwona asusa iqhwa ogwini. Le mimoya iyakwazi ukuwaqandisa amanzi. Kubuye kukhonjwe ukuthi imbobo ye-ozone eningizimu yezwe iyathinta le nto.
Iningi leqhwa lase-Antarctic ngisho nasemhlabeni. Kuyinto enwetshiwe enkulu ehlanganisa ubuso bomhlaba futhi enwetshiwe isuka olwandle nxazonke. Uqweqwe lwe-Antarctic luyancipha ngesilinganiso samakhilomitha-cubic ayikhulu ngonyaka.
Bamba izingongolo nemiphumela
Okuphambene kunjalo e-Arctic. Iningi lalapha lulwandle ngenkathi i-Antarctica izungezwe umhlaba. Lokhu kwenza ukuziphatha ngaphambi kwesimo sezulu kwehluke. Yize iqhwa lolwandle elintantayo liyancibilika, alinamphumela omncane ekukhuphukeni kwamazinga olwandle. Lokhu akunjalo ngezinguzunga zeqhwa ezintabeni noma izinguzunga zeqhwa zase-Antarctic.
Imininingwane yakamuva kakhulu yokuncibilika kwezigxobo ikhombisa ukuthi e-Antarctica kunelinye lamaqhwa amakhulu kakhulu aziwa ngegama leTotten ancibilika ngenxa yokwanda kwezinga lokushisa olwandle. Balahlekelwe inani elikhulu leqhwa futhi konke lokhu kuzothinteka ngokukhuphuka kolwandle. I-NASA imemezele ukuthi kubonakala sengathi sesifinyelele eqophelweni lokuthi ukuncibilika ezigxotsheni kungaphenduki.
Ngiyethemba ukuthi ngalolu lwazi ungafunda kabanzi ngokuncibilika emapalini.