UkuNciphisa uTshintsho lweMozulu: Ukutyala iMithi kwiArtic Kuba Mandundu ukufudumala kweHlabathi

Ukubuyiselwa kwehlathi kunye nokutyalwa kwemithi sisicwangciso esisekwe kakuhle sokunciphisa utshintsho lwemozulu. Nangona kunjalo, ukusetyenziswa kwe le ndlela kwi-arctic ibangela ukufudumala kwaye ichasene nokunciphisa utshintsho lwemozulu. Oku kungenxa yokuba ukugquma kwemithi kunciphisa i-albedo (okanye ukubonakaliswa kokukhanya kwelanga) kwaye kwandisa ubumnyama obungaphezulu obukhokelela ekufudumeni komnatha (kuba imithi ifunxa ubushushu obuninzi belanga kunekhephu). Ngaphaya koko, imisebenzi yokutyala imithi iphinda iphazamise idiba lekhabhoni yomhlaba we-arctic ogcina ikharbhon eninzi ngaphezu kwazo zonke izityalo eziseMhlabeni. Ke ngoko, indlela yokunciphisa utshintsho lwemozulu akufuneki ukuba igxile kwikhabhoni. Utshintsho lwemozulu lumalunga nolungelelwaniso lwamandla oMhlaba (umsantsa wamandla elanga ahlala kwi-atmosfera kunye namandla elanga ashiya i-atmosfera). Isixa seegesi zegreenhouse simisela ukuba bungakanani ubushushu obugcinwe kwiatmosfera yoMhlaba. Kwimimandla ye-arctic, kwi-latitudes ephezulu, i-albedo effect (oko kukuthi, ukubonakaliswa kokukhanya kwelanga kwisithuba ngaphandle kokuguqulwa kubushushu) kubaluleke kakhulu (kunempembelelo ye-greenhouse ngenxa yokugcinwa kwekhabhoni ye-atmospheric) kwi-balance balance yamandla. Ngoko ke, injongo iyonke yokunciphisa utshintsho lwemozulu ifuna indlela epheleleyo.   

Izityalo nezilwanyana zisoloko zikhupha ikharbon diokside (CO₂) emoyeni ngokuphefumla. Ezinye iziganeko zendalo ezifana nomlilo wasendle kunye nokuqhuma kwentaba-mlilo nazo zikhupha i-CO₂ emoyeni. Ibhalansi kwi-atmospheric CO₂ igcinwa kukususwa kwekhabhoni rhoqo zizityalo eziluhlaza phambi kokukhanya kwelanga ngephotosynthesis. Nangona kunjalo, imisebenzi yabantu ukususela kwi-18^th kwinkulungwane, ngakumbi ukutsalwa kunye nokutshiswa kwamafutha efosili anjengamalahle, ioyile yepetroleum, kunye negesi yendalo, kunyuse ukuxinana kwe-CO ye-atmospheric.₂.  

Okubangela umdla kukuba, ukwanda koxinzelelo lwe-CO₂ kwi-atmosfera yaziwa ngokubonisa impembelelo yekhabhoni yokuchumisa (okt, izityalo eziluhlaza photosynthesize ngakumbi ekuphenduleni ngakumbi CO₂ emoyeni). Inxalenye elungileyo yesinki yekhabhoni ekhoyo ngoku ichazwa koku kwanda kwephotosynthesis yehlabathi ukuphendula ekunyukeni kweCO.₂. Ngexesha lika-1982-2020, i-photosynthesis yehlabathi yonyuke malunga ne-12% ekuphenduleni ukonyuka kwe-17% ye-carbon dioxide ejikeleze umhlaba ukusuka kwi-360 ppm ukuya kwi-420 ppm.^1,2.  

Ngokucacileyo, ukwanda kwephotosynthesis yehlabathi akukwazi ukuthimba konke ukukhutshwa kwekhabhoni yeanthropogenic ukusukela oko kwaqala ukwenziwa kwemizi-mveliso. Ngenxa yoko, i-atmospheric carbon dioxide (CO₂) iye yanda ngokusebenzayo malunga ne-50% kwiinkulungwane ezimbini ezidlulileyo ukuya kwi-422 ppm (ngoSeptemba 2024)³ eyi-150% yexabiso layo kwi-1750. Ekubeni i-carbon dioxide (CO₂) yigesi ebalulekileyo ye-greenhouse, oku kunyuka okuphawulekayo ngokubanzi kwi-CO ye-atmospheric₂ ibe negalelo kubushushu bomhlaba nokutshintsha kwemozulu.  

Utshintsho lwemozulu lubonakala ngokunyibilika komkhenkce ovela kwincam yencani nomkhenkce, ukufudumala kolwandle, ukunyuka kwamaqondo olwandle, izikhukula, izaqhwithi ezitshabalalisayo, imbalela ebakho rhoqo nenamandla, ukunqongophala kwamanzi, amaza obushushu, imililo eqatha nezinye iimeko ezimbi. Ineziphumo ezibi kakhulu kubomi babantu nakwindlela yokuphila kungoko kunyanzelekile ukuba kuthotywe. Ngoko ke, ukunciphisa ukufudumala kwehlabathi nokunyuka kwamaqondo obushushu ukuya kutsho kwi-1.5°C ekupheleni kwale nkulungwane, i INkomfa yoTshintsho lweMozulu ye-UN uye waqaphela ukuba ukukhutshwa kwerhasi yegreenhouse yehlabathi kufuneka kucuthwe ngama-43% ngo-2030 kwaye ubize amaqela ukuba atshintshe kude kumafutha efosili ukufikelela. ukukhutshwa kwe-zero yi 2050.  

Ukongeza ekunciphiseni ukukhutshwa kwekhabhoni, isenzo semozulu sinokuxhaswa ngokususwa kwekhabhoni emoyeni. Naluphi na uphuculo lokubanjwa kwekhabhoni ye-atmospheric luya kuba luncedo.  

I-photosynthesis yolwandle yi-phytoplankton, i-kelp, kunye ne-algal planktons elwandle inoxanduva malunga nesiqingatha se-carbon capture. Kucetyiswa ukuba i-microalgal biotechnology inokuba negalelo ekubanjweni kwekhabhoni ngephotosynthesis. Ukubuyisela umva ukugawulwa kwamahlathi ngokutyalwa kwemithi kunye nokubuyiselwa komhlaba wamahlathi kunokuba luncedo kakhulu ekunciphiseni imozulu. Olunye uphononongo lwafumanisa ukuba ukuphuculwa kwamahlathi ehlabathi kunokwenza igalelo elibalulekileyo. Ibonise ukuba umthamo wekhenopi yemithi yehlabathi phantsi kwemozulu yangoku uziihektare ezibhiliyoni ezi-4.4 nto leyo ethetha ukuba i-0.9 yeebhiliyoni ezongezelelweyo ze-canopy cover (elingana ne-25% yokwanda kwendawo enamahlathi) inokudalwa emva kokungabandakanyi indawo ekhoyo. Olu khuselo lungaphezulu lwecanopy ukuba ludaliwe luya kuthinjwa kwaye lugcine malunga nama-205 egigatonnes ekhabhoni efikelela kuma-25% equla lekhabhoni ekhoyo ngoku. Ukubuyiselwa kwamahlathi ehlabathi kunyanzelekile kwakhona ngenxa yokuba utshintsho lwemozulu olungaphazamisekiyo lunokukhokelela ekuncitshisweni kweehektare ezimalunga nezigidi ezingama-223 zamahlathi (ubukhulu becala kwiindawo ezitshisayo) kunye nelahleko yeentlobo ngeentlobo zezinto eziphilayo ezinxulumeneyo ngo-2050.^4,5. 

Ukutyalwa kwemithi kwingingqi ye-arctic  

Ummandla we-Arctic ubhekisa kwindawo esemantla yoMhlaba ngaphezu kwe-66° 33′N yesibanzi ngaphakathi kwesangqa seartic. Uninzi lwalo mmandla (malunga nama-60%) luhlala umkhenkce wolwandle ogqunywe yi-arctic ocean. I-Artic landmass ibekwe malunga nemida esemazantsi yolwandlekazi oluxhasa i-tundra okanye ihlathi le-boreal elingasentla.  

Amahlathi e-Boreal (okanye i-taiga) afumaneka emazantsi e-Arctic Circle kwaye abonakaliswe ngamahlathi e-coniferous abandakanya uninzi lwepayini, i-spruces, kunye ne-larches. Inobusika obude, obubandayo kunye nehlobo elifutshane nelimanzi. Kukho ukuxhaphaka kwemithi ekwaziyo ukunyamezela ukubanda, ethwala ikhowuni, ehlala iluhlaza, i<em>coniferous (ipayini, i<em>spruces, nefirs) egcina amagqabi ayo amile njengenaliti unyaka wonke. Xa kuthelekiswa namahlathi anemozulu epholileyo kunye namahlathi ashinyeneyo, amahlathi ashinyeneyo anemveliso esezantsi esisiseko, aneentlobo ngeentlobo zezityalo ezimbalwa kwaye akanalwakhiwo lwamahlathi. Ngakolunye uhlangothi, i-arctic tundra itholakala kumntla wamahlathi e-boreal kwimimandla ye-Artic ye-hemisphere esenyakatho, apho i-subsoil igcinwe ngokusisigxina. Lo mmandla ubanda kakhulu nge-avareji yamaqondo obushushu asebusika nasehlotyeni aphakathi kwe -34°C kunye ne-3°C – 12°C ngokulandelelanayo. Umhlaba ongaphantsi unomkhenkce ngokusisigxina (permafrost) kungoko iingcambu zezityalo zingenako ukungena nzulu emhlabeni kwaye izityalo ziphantsi emhlabeni. I-Tundra inemveliso ephantsi kakhulu, ukuhlukahluka kweentlobo eziphantsi kunye nexesha elifutshane lokukhula kweeveki ze-10 xa izityalo zikhula ngokukhawuleza ekuphenduleni ukukhanya okude kwemini.  

Ukukhula kwemithi kwimimandla ye-arctic kuchatshazelwa yi-permafrost kuba amanzi angumkhenkce angaphantsi komhlaba anqanda ukukhula kweengcambu. Uninzi lwe-tundra ine-permafrost eqhubekayo ngelixa amahlathi e-boreal ekhona kwiindawo ezine-permafrost encinci okanye engekhoyo. Nangona kunjalo, i-arctic permafrost ayichaphazeleki.  

Njengoko imozulu ye-arctic ishushu (nto leyo eyenzekayo ngokukhawuleza okuphindwe kabini kunomndilili wehlabathi), isiphumo sokunyibilika kunye nokulahleka kwe-permafrost kuya komeleza ukusinda kwezithole zomthi kwangoko. Ubukho be-shrub canopy kwafunyaniswa ukuba bunxulunyaniswa ngokufanelekileyo nokuphila ngakumbi kunye nokukhula kwezithole zibe yimithi. Ukwakhiwa kweentlobo kunye nokusebenza kwemixokomelwano yokuphilisana kwendalo kummandla kuqhuba utshintsho olukhawulezayo. Njengoko imozulu ishushu kunye nomkhenkce uwohloka, uhlaza lunokutshintsha ukusuka kwi-arctic engenamthi ukuya kulawulo lomthi kwixesha elizayo.⁶.  

Ngaba uhlaza luya kutshintshela kwindawo elawulwa yimithi ye-arctic ukunciphisa umoya we-CO₂ ngokusebenzisa iphotosynthesis eyandisiweyo kunye nokunceda ukunciphisa utshintsho lwemozulu? Ngaba ummandla we-arctic unokuthathelwa ingqalelo ekugawulweni kwamahlathi ukuze kususwe i-atmospheric CO₂. Kuzo zombini ezi meko, i-arctic permafrost kufuneka inyibilike okanye ithobeke kuqala ukuze ivumele ukukhula kwemithi. Nangona kunjalo, ukunyibilika kwe-permafrost kukhupha imethane emoyeni eyigesi enamandla yegreenhouse kwaye inegalelo ekufudumaleni ngakumbi. Ukukhutshwa kwemethane kwi-permafrost nako kunegalelo kwimililo enkulu yasendle kulo mmandla.  

Ngokuphathelele isicwangciso sokususwa kwe-CO₂ ngokusebenzisa i-photosynthesis ngokutyalwa kwamahlathi okanye ukucwangciswa kwemithi kwingingqi ye-artic kunye nokunciphisa ukufudumala kunye nokutshintsha kwemozulu, abaphandi⁷ ifumanise ukuba le ndlela ayifanelekanga kummandla kwaye ichasene nokunciphisa utshintsho lwemozulu. Oku kungenxa yokuba ukugquma komthi kunciphisa i-albedo (okanye ukubonakaliswa kokukhanya kwelanga) kwaye kwandisa ubumnyama obungaphezulu obukhokelela ekufudumaleni komnatha kuba imithi ifunxa ubushushu obuninzi belanga kunekhephu. Ngaphaya koko, imisebenzi yokutyalwa kwemithi iphinda iphazamise idama lekhabhoni lomhlaba we-arctic ogcina ikhabhoni eninzi ngaphezu kwazo zonke izityalo eziseMhlabeni.  

Ke ngoko, indlela yokunciphisa utshintsho lwemozulu akufuneki ukuba igxile kwikhabhoni. Ukutshintsha kwemozulu kumalunga nolungelelwaniso lwamandla oMhlaba (umsantsa wamandla elanga ahlala kwi-atmosfera kunye namandla elanga aphuma emoyeni). Iigesi zegreenhouse zimisela ukuba bungakanani ubushushu obugcinwe kwiatmosfera yoMhlaba. Kwimimandla ye-arctic kwi-latitudes ephezulu, i-albedo effect (oko kukuthi, ukubonakaliswa kokukhanya kwelanga kubuyele esithubeni ngaphandle kokuguqulwa kubushushu) kubaluleke kakhulu (kunokugcinwa kwekhabhoni ye-atmospheric) kwibhalansi yamandla ewonke. Ngoko ke, injongo iyonke yokunciphisa utshintsho lwemozulu ifuna indlela ebanzi.  

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Iingxelo:  

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