Ukunciphisa Ukushintsha Kwesimo Sezulu: Ukutshala Izihlahla E-Artic Kuba Kubi Ukufudumala Kwembulunga yonke

Ukubuyiselwa kwehlathi kanye nokutshalwa kwezihlahla kuyisu elisungulwe kahle lokunciphisa ukuguquguquka kwesimo sezulu. Nokho, ukusetshenziswa le ndlela e-arctic yenza kube kubi ukufudumala futhi iphikisana nokunciphisa ukuguquguquka kwesimo sezulu. Lokhu kungenxa yokuthi ukumboza kwezihlahla kunciphisa i-albedo (noma ukubonakaliswa kokukhanya kwelanga) futhi kwandisa ubumnyama obungaphezulu okuholela ekufudumaleni kwenetha (ngoba izihlahla zimunca ukushisa okukhulu elangeni kuneqhwa). Ngaphezu kwalokho, imisebenzi yokutshala izihlahla iphinde iphazamise i-carbon pool yenhlabathi ye-arctic egcina ikhabhoni eningi ukwedlula zonke izitshalo eziseMhlabeni. Ngakho-ke, indlela yokunciphisa ukuguquguquka kwesimo sezulu akudingeki ukuthi igxile kukhabhoni. Ukushintsha kwesimo sezulu kumayelana nokulingana kwamandla omhlaba (inani lamandla elanga ahlala emkhathini kanye namandla elanga aphuma emkhathini). Inani lamagesi abamba ukushisa linquma ukuthi kungakanani ukushisa okugcinwe emkhathini woMhlaba. Ezifundeni zase-arctic, ezindaweni eziphakeme, umphumela we-albedo (okungukuthi, ukukhanya kwelanga kubuyele emkhathini ngaphandle kokuguqulwa kube ukushisa) kubaluleke kakhulu (kunomphumela we-greenhouse ngenxa yokugcinwa kwekhabhoni yasemkhathini) kungqikithi yamandla ebhalansi. Ngakho-ke, umgomo ophelele wokunciphisa ukuguquka kwesimo sezulu udinga indlela ephelele.   

Izitshalo nezilwane zikhipha isikhutha ngokuqhubekayo (CO₂) emkhathini ngokuphefumula. Ezinye izenzakalo zemvelo ezifana nemililo yequbula nokuqhuma kwentaba-mlilo nazo zikhulula i-CO₂ emkhathini. Ibhalansi ku-atmospheric CO₂ igcinwa ukuhlukaniswa kwekhabhoni okuvamile yizitshalo eziluhlaza lapho kukhona ukukhanya kwelanga nge-photosynthesis. Nokho, imisebenzi yabantu kusukela 18^th ikhulu leminyaka, ikakhulukazi ukukhishwa kanye nokushiswa kwezinto zokubasa ezimbiwa phansi njengamalahle, uwoyela we-petroleum, negesi yemvelo, kukhuphule ukugcwala kwe-CO emkhathini.₂.  

Kuyathakazelisa ukuthi ukwanda kokuhlushwa kwe-CO₂ emkhathini kuyaziwa ukukhombisa umphumela wokuvundisa kwekhabhoni (okungukuthi, izitshalo eziluhlaza zenza i-photosynthesize kakhulu ekuphenduleni ku-CO eyengeziwe₂ emkhathini). Ingxenye enhle yokucwila kwekhabhoni yamanje yasemhlabeni ibangelwa yilokhu kwanda kwe-photosynthesis yomhlaba wonke ngenxa yokukhuphuka kwe-CO.₂. Phakathi kuka-1982-2020, i-photosynthesis yomhlaba wonke yenyuka cishe ngo-12% ngenxa yokwanda kwe-carbon dioxide emkhathini ngo-17% ukusuka ku-360 ppm kuya ku-420 ppm.^1,2.  

Ngokusobala, ukwanda kwe-photosynthesis yomhlaba wonke akukwazi ukukhipha konke ukukhishwa kwekhabhoni ye-anthropogenic selokhu kwaqala ukwenziwa kwezimboni. Ngenxa yalokho, i-atmospheric carbon dioxide (CO₂) inyuke ngempumelelo cishe ngo-50% kula makhulu amabili eminyaka edlule yafinyelela ku-422 ppm (ngoSepthemba 2024)³ okuyi-150% yenani layo ngo-1750. Njengoba i-carbon dioxide (CO₂) iyigesi ebamba ukushisa ebalulekile, lokhu kwanda okuphawulekayo okuphelele kwe-CO emkhathini₂ kube nomthelela ekushiseni komhlaba nasekushintsheni kwesimo sezulu.  

Ukushintsha kwesimo sezulu kubonakala ngendlela yokuncibilika kweqhwa nezinguzunga zeqhwa, ukufudumala kolwandle, ukukhuphuka kwamazinga olwandle, izikhukhula, iziphepho eziyingozi, isomiso esivamile nesishubile, ukuntuleka kwamanzi, amagagasi okushisa, imililo enamandla nezinye izimo ezimbi. Kunemiphumela emibi kakhulu ezimpilweni zabantu nasezimpilweni zabantu yingakho kubalulekile ukuncishiswa. Ngakho-ke, ukuze kukhawulwe ukufudumala kwembulunga yonke nokukhuphuka kwezinga lokushisa libe ngu-1.5°C ekupheleni kwaleli khulu leminyaka, i- Ingqungquthela ye-UN yokuguquguquka kwesimo sezulu ubonile ukuthi ukukhishwa kwegesi ebamba ukushisa emhlabeni wonke kumele kwehliswe ngama-43% ngo-2030 futhi ubize amaqembu ukuthi asuke kude nezibaso ezimbiwa phansi ukuze afinyelele. ukukhishwa okungu-zero okuphelele by 2050.  

Ngaphezu kokunciphisa ukukhishwa kwekhabhoni, isenzo sezulu singase futhi sisekelwe ukukhishwa kwekhabhoni emkhathini. Noma yikuphi ukuthuthukiswa ekuthwebuleni ikhabhoni yasemkhathini kungaba usizo.  

I-photosynthesis yasolwandle eyenziwa yi-phytoplankton, i-kelp, ne-algal plankton olwandle inesibopho sokuthatha ingxenye yekhabhoni. Kuphakanyiswa ukuthi i-microalgal biotechnology ingaba nomthelela ekubanjweni kwekhabhoni nge-photosynthesis. Ukubuyisela emuva ukugawulwa kwamahlathi ngokutshalwa kwezihlahla nokubuyiselwa komhlaba wamahlathi kungaba usizo kakhulu ekunciphiseni isimo sezulu. Olunye ucwaningo lwathola ukuthi ukuthuthukisa ukumboza kwamahlathi emhlabeni wonke kungaba negalelo elikhulu. Kubonise ukuthi umthamo we-canopy yezihlahla emhlabeni wonke ngaphansi kwesimo sezulu samanje ungamahektha ayizigidi eziyizinkulungwane ezingu-4.4 okusho ukuthi amahektha engeziwe angamabhiliyoni angu-0.9 ekhava ye-canopy (okulingana no-25% ukwanda endaweni enamahlathi) angadalwa ngemva kokungabandakanyi ikhava ekhona. Lesi sembozo se-canopy eyengeziwe uma sidaliwe singathatha futhi sigcine cishe amagigatonne angama-205 ekhabhoni elingana cishe nama-25% echibi lamanje lekhabhoni esemoyeni. Ukubuyiselwa kwamahlathi emhlabeni wonke kubalulekile futhi ngenxa yokuthi ukuguquka kwesimo sezulu okungaphazamiseki kungaholela ekuncipheni kwamahektha alinganiselwa ezigidini ezingama-223 embozwe yamahlathi (ikakhulukazi ezindaweni ezishisayo) kanye nokulahlekelwa kwezinhlobonhlobo zezinto eziphilayo ezihambisana nakho ngo-2050.^4,5. 

Ukutshala izihlahla endaweni ye-arctic  

Isifunda sase-Arctic sibhekisela engxenyeni esenyakatho yoMhlaba ngaphezu kwe-latitude engu-66° 33′N ngaphakathi kwendingilizi ye-artic. Ingxenye enkulu yalesi sifunda (cishe ama-60%) igcwele iqhwa lolwandle elimbozwe yi-arctic ocean. I-artic landmass itholakala emaphethelweni aseningizimu ye-artic ocean esekela i-tundra noma ihlathi le-boreal elisenyakatho.  

Amahlathi e-Boreal (noma ama-taiga) atholakala eningizimu ye-Arctic Circle futhi abonakala ngamahlathi e-coniferous ahlanganisa kakhulu amaphayini, ama-spruces, nama-larches. Inobusika obude, obubandayo kanye nehlobo elifushane nelimanzi. Ziningi izihlahla ezikwazi ukumelana nokubanda, ezithwala amakhoni, ezihlala ziluhlaza, ze-coniferous (uphayini, ama-spruces, namafir) ezigcina amaqabunga azo amise okwenaliti unyaka wonke. Uma kuqhathaniswa namahlathi asezingeni elipholile namahlathi amanzi ashisayo, amahlathi e-boreal anokukhiqiza okuphansi okuyisisekelo, anezinhlobonhlobo ezimbalwa zezitshalo futhi awanazo izakhiwo zamahlathi. Ngakolunye uhlangothi, i-arctic tundra itholakala enyakatho yehlathi le-boreal ezifundeni ze-Artic enyakatho nenkabazwe, lapho inhlabathi engaphansi iqhwa unomphela. Lesi sifunda sibanda kakhulu njengoba izinga lokushisa elijwayelekile lasebusika nelasehlobo liphakathi kuka -34°C no-3°C – 12°C ngokulandelana. Inhlabathi engaphansi iqhwa unomphela (i-permafrost) yingakho izimpande zezitshalo azikwazi ukungena zijule emhlabathini futhi izitshalo ziphansi phansi. I-Tundra inokukhiqiza okuphansi kakhulu, ukuhlukahluka kwezinhlobo eziphansi kanye nenkathi yokukhula emfushane yamaviki angu-10 lapho izitshalo zikhula ngokushesha ngenxa yokukhanya okude kwemini.  

Ukukhula kwesihlahla ezindaweni zase-arctic kuthintwa i-permafrost ngoba amanzi ayiqhwa avimbela ukukhula kwezimpande ezijulile. Iningi le-tundra line-permafrost eqhubekayo kuyilapho amahlathi e-boreal ekhona ezindaweni ezine-permafrost encane noma engekho. Nokho, i-arctic permafrost ayithinteki.  

Njengoba isimo sezulu sase-arctic sishisa (okwenzeka ngokushesha okuphindwe kabili kunesilinganiso somhlaba), ukuncibilika nokulahlekelwa kwe-permafrost kungathuthukisa ukusinda kwezithombo zezihlahla zakuqala. Ukuba khona kwe-shrub canopy kwatholakala ukuthi kuhlotshaniswa kahle nokusinda okuqhubekayo nokukhula kwezithombo zibe izihlahla. Ukwakheka kwezinhlobo zezilwane nokusebenza kwe-ecosystem esifundeni kushintsha ngokushesha. Njengoba isimo sezulu sishisa futhi iqhwa liwohloka, izimila zingase zishintshe zisuke endaweni engenasihlahla ziye ezihlahleni esikhathini esizayo.⁶.  

Ingabe uhlaza lungashintsha lube yi-arctic landscape ebuswa yizihlahla lunciphise i-CO emkhathini₂ ngokusebenzisa i-photosynthesis ethuthukisiwe futhi usize ukunciphisa ukuguquguquka kwesimo sezulu? Ingabe isifunda se-arctic singacatshangelwa ukugawulwa kwamahlathi ukuze kususwe i-CO emkhathini₂. Kuzo zombili izimo, i-arctic permafrost kufanele incibilike noma yonise kuqala ukuze ivumele ukukhula kwezihlahla. Kodwa-ke, ukuncibilika kwe-permafrost kukhipha i-methane emkhathini okuyigesi enamandla ebamba ukushisa futhi okunomthelela ekuqhubekeni kokufudumala. Ukukhishwa kwe-methane ku-permafrost nakho kunomthelela emililo yequbula emikhulu esifundeni.  

Ngokuqondene nesu lokususwa kwe-atmospheric CO₂ ngokusebenzisa i-photosynthesis ngokutshalwa kwezihlahla noma ukutshala izihlahla endaweni ye-artic kanye nokunciphisa ukufudumala nokuguquka kwesimo sezulu, abacwaningi⁷ uthole ukuthi le ndlela ayifanele isifunda futhi iphikisana nokunciphisa ukuguquguquka kwesimo sezulu. Lokhu kungenxa yokuthi ukumboza kwezihlahla kunciphisa i-albedo (noma ukubonakaliswa kokukhanya kwelanga) futhi kukhulisa ubumnyama obungaphezulu obuholela ekufudumaleni kwenethi ngoba izihlahla zimunca ukushisa okukhulu kwelanga kuneqhwa. Ngaphezu kwalokho, imisebenzi yokutshala izihlahla iphinde iphazamise i-carbon pool yenhlabathi ye-arctic egcina ikhabhoni eningi ukwedlula zonke izitshalo eziseMhlabeni.  

Ngakho-ke, indlela yokunciphisa ukuguquguquka kwesimo sezulu akudingeki ukuthi igxile kukhabhoni. Ukushintsha kwesimo sezulu kumayelana nokulingana kwamandla omhlaba (inani lamandla elanga ahlala emkhathini kanye namandla elanga aphuma emkhathini). Amagesi abamba ukushisa anquma ukuthi kungakanani ukushisa okugcinwe emkhathini woMhlaba. Ezifundeni ze-arctic ezindaweni eziphakeme, umphumela we-albedo (okungukuthi, ukukhanya kwelanga kubuyele emkhathini ngaphandle kokuguqulelwa ekushiseni) kubaluleke kakhulu (kunokugcinwa kwekhabhoni yasemkhathini) ngebhalansi ephelele yamandla. Ngakho-ke, umgomo ophelele wokunciphisa ukuguquka kwesimo sezulu udinga indlela ephelele.  

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References:  

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