Ososayensi nosopolitiki bathi sibhekene nenkinga yeplanethi ngenxa yokuguquka kwesimo sezulu.
Kodwa buyini ubufakazi bokufudumala kwembulunga yonke futhi sazi kanjani ukuthi kubangelwa abantu?
Sazi kanjani ukuthi umhlaba uya ukufudumala?
Iplanethi yethu ibilokhu ifudumala ngokushesha kusukela ekuqaleni kweNguquko Yezimboni.
Izinga lokushisa elijwayelekile endaweni yoMhlaba likhuphuke cishe ngo-1.1C kusukela ngo-1850. Ngaphezu kwalokho, ngayinye yamashumi amane eminyaka edlule ibifudumala kunanoma iyiphi eyandulelayo, kusukela maphakathi nekhulu le-19.
Lezi ziphetho zivela ekuhlaziyeni kwezigidi zezilinganiso eziqoqwe ezingxenyeni ezihlukahlukene zomhlaba.Ukufundwa kwezinga lokushisa kuqoqwa iziteshi zesimo sezulu emhlabeni, emikhunjini nangamasathelayithi.
Amaqembu amaningi azimele ososayensi afinyelele umphumela ofanayo - ukukhuphuka kwezinga lokushisa okuhambisana nokuqala kwenkathi yezimboni.
Ososayensi bangakwazi ukwakha kabusha ukuguquguquka kwezinga lokushisa ngisho nangemuva kwesikhathi.
Amasongo ezihlahla, ama-ice cores, i-lake sediments namakhorali konke kurekhoda isignesha yesimo sezulu esidlule.
Lokhu kunikeza umongo odingeka kakhulu esigabeni samanje sokufudumala.Eqinisweni, ososayensi balinganisela ukuthi uMhlaba ubungakashisi ngale ndlela iminyaka engaba ngu-125,000.
Sazi kanjani ukuthi abantu banembangela yokufudumala kwembulunga yonke?
Amagesi abamba ukushisa kweLanga - ayisixhumanisi esibalulekile phakathi kokukhuphuka kwezinga lokushisa nemisebenzi yabantu.Okubaluleke kakhulu i-carbon dioxide (CO2), ngenxa yobuningi bayo emkhathini.
Singasho futhi ukuthi i-CO2 icupha amandla eLanga.Amasathelayithi abonisa ukushisa okuncane okuvela eMhlabeni kubalekela emkhathini ngamaza amaza amaza lapho i-CO2 imunca khona amandla aphumayo.
Ukushisa izibaso ezimbiwa phansi kanye nokugawula izihlahla kuholela ekuphumeni kwale gesi ebamba ukushisa.Yomibili le misebenzi yaqhuma ngemva kwekhulu le-19, ngakho-ke akumangalisi ukuthi i-CO2 yasemkhathini yanda ngesikhathi esifanayo.
Kukhona indlela esingabonisa ngayo ukuthi le CO2 eyengeziwe ivela kuphi.Ikhabhoni ekhiqizwe ngokushisa izibaseli ezimbiwa phansi inesiginesha yamakhemikhali ehlukile.
Amasongo esihlahla kanye neqhwa elisezindaweni ezishisayo zombili zirekhoda izinguquko kukhemistri yasemkhathini.Uma behlolwa bakhombisa ukuthi ikhabhoni - ikakhulukazi emithonjeni yezinsalela - inyuke kakhulu kusukela ngo-1850.
Ukuhlaziya kubonisa ukuthi iminyaka engu-800,000, i-CO2 yasemkhathini ayizange ikhuphuke ngaphezu kwezingxenye ezingu-300 ngesigidi (ppm).Kodwa kusukela kuNguquko Yezimboni, ukugxilwa kwe-CO2 kukhuphuke kwafinyelela ezingeni lakhona lamanje elicishe libe ngu-420 ppm.
Imifanekiso yama-computer, eyaziwa ngokuthi izibonelo zesimo sezulu, iye yasetshenziswa ukuze kuboniswe lokho obekungenzeka emazingeni okushisa ngaphandle kwenani elikhulu lamagesi abamba ukushisa akhishwa abantu.
Baveza ukuthi bekuzoba nokuncane ukufudumala kwembulunga yonke - futhi mhlawumbe nokupholisa okuthile - phakathi nekhulu lama-20 nelama-21, ukube izinto zemvelo bezinomthelela esimweni sezulu.
Kuphela lapho izici zomuntu zethulwa lapho amamodeli angachaza ukunyuka kwezinga lokushisa.
Imuphi umthelela abantu abanawo emhlabeni?
Izinga lokushisisa Umhlaba oseluke latholwa kakade libikezelwa ukuthi lingabangela izinguquko ezibalulekile emhlabeni osizungezile.
Ukubhekwa komhlaba wangempela kwalezi zinguquko kufana namaphethini ososayensi abalindele ukuwabona ngokufudumala okubangelwa umuntu.Zihlanganisa:
***Iqhwa laseGreenland nelase-Antarctic liyancibilika ngokushesha
***Inani lezinhlekelele ezihlobene nesimo sezulu liye landa ngesilinganiso seminyaka emihlanu eminyakeni engu-50
***Amazinga olwandle omhlaba wonke akhuphuke ngo-20cm (8ins) ekhulwini elidlule futhi asakhuphuka
***Kusukela ngeminyaka yawo-1800s, izilwandle seziphenduke i-asidi engaphezulu ngo-40%, ethinta impilo yasolwandle.
Kodwa bekungafudumali yini esikhathini esidlule?
Kube nezikhathi ezishisayo ezimbalwa phakathi nesikhathi esedlule soMhlaba.
Cishe eminyakeni eyizigidi ezingu-92 edlule, isibonelo, amazinga okushisa ayephezulu kangangokuthi kwakungekho amaqhwa eqhwa futhi izidalwa ezinjengengwenya zazihlala kude enyakatho njenge-Canadian Arctic.
Nokho, lokho akufanele kududuze muntu ngoba abantu babengekho.Ngezinye izikhathi esikhathini esidlule, izinga lolwandle lalingama-25m (80ft) ngaphezu kwamanje.Ukuphakama okungu-5-8m (16-26ft) kuthathwa njengokwanele ukucwilisa iningi lamadolobha asogwini lomhlaba.
Kunobufakazi obuningi bokushabalala kobuningi bempilo ngalezi zikhathi.Futhi izibonelo zesimo sezulu zisikisela ukuthi, ngezinye izikhathi, izindawo ezishisayo zazingase zibe “izindawo ezifile”, zishise kakhulu ukuthi izinhlobo eziningi zezilwane ziphile.
Lokhu kuguquguquka phakathi kokushisa nokubanda kudalwe izinto ezehlukene, okuhlanganisa indlela uMhlaba onyakaza ngayo lapho uzungeza iLanga isikhathi eside, ukuqhuma kwentaba-mlilo kanye nemijikelezo yezulu yesikhashana efana ne-El Niño.
Sekuyiminyaka eminingi amaqembu alabo okuthiwa “abangabazayo” besimo sezulu bengabaza isisekelo sesayensi sokufudumala kwembulunga yonke.
Nokho, cishe bonke ososayensi abanyathelisa njalo emaphephandabeni abuyekezwa ngontanga manje bayavumelana ngezimbangela zamanje zokushintsha kwesimo sezulu.
Umbiko obalulekile we-UN okhishwe ngo-2021 uthe "akungabazeki ukuthi ithonya lomuntu lifudumeza umkhathi, izilwandle nomhlaba".
Ukuze uthole ulwazi olwengeziwe, sicela ubuke:https://www.bbc.com/news/science-environment-58954530
Isikhathi sokuthumela: Oct-21-2022