Izazinzulu kunye nabezopolitiko bathi sijongene nengxaki enkulu emhlabeni ngenxa yotshintsho lwemozulu.
Kodwa yintoni ubungqina bokufudumala kwehlabathi kwaye sazi njani ukuba kubangelwa ngabantu?
Sazi njani ukuba ihlabathi liya lifudumala?
Iplanethi yethu ibishushu ngokukhawuleza ukusukela ekuqaleni kweNguquko yezeMizi-mveliso.
Ubushushu obuqhelekileyo kumphezulu woMhlaba bunyuke malunga ne-1.1C ukusukela ngo-1850. Ngaphezu koko, iminyaka engamashumi amane edlulileyo ibishushu kunayo nayiphi na eyandulelayo, ukusukela phakathi kwinkulungwane ye-19.
Ezi zigqibo zivela kuhlalutyo lwezigidi zeemilinganiselo eziqokelelwe kwiindawo ezahlukeneyo zehlabathi. Ukufundwa kobushushu kuqokelelwa zizikhululo zemozulu emhlabeni, kwiinqanawa nakwiisathelayithi.
Amaqela amaninzi azimeleyo eengcali zesayensi afikelele kwisiphumo esifanayo - ukunyuka kwamaqondo obushushu okuhambelana nokuqala kwexesha lezoshishino.
Izazinzulu ziyakwazi ukuphinda ziqwalasele ukuguquguquka kobushushu nangakumbi emva kwexesha.
Izangqa zemithi, ii-ice core, i-sediments zasechibini kunye neekorale zonke zirekhoda uphawu lwemozulu yangaphambili.
Oku kunika umxholo ofunekayo kakhulu kwinqanaba langoku lokufudumala. Enyanisweni, izazinzulu ziqikelela ukuba uMhlaba awuzange ube shushu kangaka kangangeminyaka emalunga ne-125,000.
Sazi njani ukuba abantu banoxanduva lokufudumala kwehlabathi?
Iigesi zegreenhouse - ezibamba ubushushu beLanga - zizinto ezibalulekileyo phakathi kokunyuka kobushushu kunye nemisebenzi yabantu. Eyona ibalulekileyo yicarbon dioxide (CO2), ngenxa yobuninzi bayo emoyeni.
Singabona nokuba i-CO2 yayo ibamba amandla eLanga. Iisathelayithi zibonisa ubushushu obuncinci obuphuma eMhlabeni obuphuma buye esibhakabhakeni kanye kumaza obude apho i-CO2 ifunxa khona amandla aphumayo.
Ukutshisa amafutha efosili nokugawula imithi kukhokelela ekukhutshweni kwale gesi ibangela ukufudumala komhlaba. Zombini ezi zinto zanda emva kwenkulungwane ye-19, ngoko ke akumangalisi ukuba i-CO2 yomoya inyuke ngexesha elifanayo.
Kukho indlela esinokubonisa ngayo ngokucacileyo apho le CO2 eyongezelelweyo ivela khona. Ikhabhoni eveliswa kukutshisa amafutha efosili inophawu olwahlukileyo lwekhemikhali.
Izangqa zemithi kunye nomkhenkce we-polar zombini zirekhoda utshintsho kwikhemistri yomoya. Xa zihlolwa zibonisa ukuba ikhabhoni - ingakumbi evela kwimithombo yamathambo - inyuke kakhulu ukususela ngo-1850.
Uhlalutyo lubonisa ukuba kangangeminyaka engama-800,000, i-CO2 esemoyeni ayizange inyuke ngaphezu kwama-300 eenxalenye ngesigidi (ppm). Kodwa ukusukela kwiNguquko yoShishino, uxinaniso lwe-CO2 luye lwanda lwaya kufikelela kwinqanaba langoku eliphantse libe yi-420 ppm.
Iikhompyutha ezisebenzisa ukulinganisa, ezaziwa ngokuba ziimodeli zemozulu, ziye zasetyenziswa ukubonisa oko bekuya kwenzeka kumaqondo obushushu ngaphandle kobuninzi beegesi ezibangela ukufudumala komhlaba ezikhutshwa ngabantu.
Zityhila ukuba bekungayi kubakho bushushu bungako behlabathi - mhlawumbi nobushushu obuthile - kwinkulungwane yama-20 neye-21, ukuba nje izinto zendalo bezinefuthe kwimozulu.
Kuphela xa izinto ezisetyenziswa ngabantu ezinokuthi iimodeli zichaze ukunyuka kobushushu.
Iyintoni impembelelo abantu abanayo kule planethi?
Inqanaba lokufudumeza uMhlaba sele lifikile liqikelelwa ukuba liza kubangela utshintsho olukhulu kwihlabathi elisingqongileyo.
Uqwalaselo lokwenyani lolu tshintsho luhambelana neendlela izazinzulu ezilindele ukuzibona xa kufudumala okubangelwa ngabantu. Ziquka:
***Iingqayi zomkhenkce zaseGreenland naseAntarctica ziyanyibilika ngokukhawuleza
***Inani leentlekele ezinxulumene nemozulu linyuke ngesiqingatha seminyaka emihlanu kwiminyaka engama-50 edlulileyo
***Amanqanaba olwandle kwihlabathi liphela anyuke nge-20cm (8 intshi) kwinkulungwane edlulileyo kwaye asanyuka
***Ukususela ngeminyaka yoo-1800, iilwandle ziye zaba ne-asidi engaphezulu ngama-40%, nto leyo echaphazela ubomi baselwandle.
Kodwa bekungashushu na ngaphambili?
Bekukho amaxesha amaninzi ashushu ngexesha elidlulileyo loMhlaba.
Umzekelo, malunga neminyaka eyi-92 yezigidi eyadlulayo, amaqondo obushushu ayephezulu kangangokuba kwakungekho zikhephu zomkhenkce ezikwi-polar kwaye izidalwa ezifana neengwenya zazihlala kude emantla njenge-Canadian Arctic.
Nangona kunjalo, oko akufanele kuthuthuzele mntu, kuba abantu babengekho. Ngamanye amaxesha ngaphambili, umgangatho wolwandle wawuphezulu nge-25m (80ft) kunangoku. Ukuphakama nge-5-8m (16-26ft) kuthathwa njengokwaneleyo ukuntywilisela uninzi lwezixeko ezikunxweme lwehlabathi.
Kukho ubungqina obuninzi bokuphela kobomi ngezi zihlandlo. Kwaye iimodeli zemozulu zibonisa ukuba, ngamanye amaxesha, iindawo ezishushu zinokuba "ziindawo ezifileyo", zishushu kakhulu ukuba uninzi lweentlobo zezilwanyana lungasinda.
Oku kuguquguquka phakathi kobushushu nokubanda kubangelwe zizinto ezahlukeneyo, kuquka indlela uMhlaba oshukuma ngayo njengoko ujikeleza iLanga ixesha elide, ukuqhuma kweentaba-mlilo kunye nemijikelo yemozulu yexesha elifutshane efana ne-El Niño.
Kangangeminyaka emininzi, amaqela abantu ababizwa ngokuba "ngabathandabuziyo" ngemozulu aye athandabuza isiseko sesayensi sokufudumala kwehlabathi.
Nangona kunjalo, phantse zonke izazinzulu ezipapasha rhoqo kwiijenali eziphononongwa ngoontanga ngoku ziyavumelana ngezizathu zangoku zotshintsho lwemozulu.
Ingxelo ephambili ye-UN eyakhutshwa ngo-2021 yathi "akunakuphikiswa ukuba impembelelo yoluntu iye yafudumeza umoya, iilwandle kunye nomhlaba".
Ukuze ufumane ulwazi oluthe kratya, nceda ujonge:https://www.bbc.com/news/science-environment-58954530
Ixesha lokuthumela: Okthobha-21-2022
