Ukupakisha i-ice coverage kwi-Arctic Ocean iye yawela kwinqanaba lesibini eliphantsi ukusuka ekuqaphelisweni kwesathelayithi kwaqala ngo-1979, oososayensi baseburhulumenteni base-US bathi ngoMsombuluko.
Ukuza kuthi ga kule nyanga, kube kanye kuphela kule minyaka ingama-42 idlulileyo ukhakhayi olunomkhenkce loMhlaba lugqunywe ngaphantsi kwe-4 million square kilometers (1.5 million square miles).
IArctic inokuba namava ayo ehlobo lokuqala elingenamkhenkce kwangoko ngo-2035, abaphandi baxela kwinyanga ephelileyo kwijenali yoTshintsho lweMozulu yeNdalo.
Kodwa lonke elo khephu elinyibilikayo kunye nomkhenkce alinyusi ngokuthe ngqo amanqanaba olwandle, kanye njengokuba iityhubhu zomkhenkce ezinyibilikayo zingachithi iglasi yamanzi, nto leyo ephakamisa umbuzo onzima: Ngubani okhathalayo?
Kuyavunywa ukuba, ezi ziindaba ezimbi kwiibhere ezimhlophe, ezithi, ngokutsho kohlolisiso lwakutshanje, sele zisendleleni eya ekutshatyalalisweni.
Ewe, ngokuqinisekileyo oku kuthetha inguqu enzulu yommandla wendalo yaselwandle, ukusuka kwi-phytoplankton ukuya kwiminenga.
Njengoko kuvela, kukho izizathu ezininzi zokuba nexhala malunga neziphumo ebezingalindelekanga zokucutheka komkhenkce wolwandle lweArctic.
Mhlawumbi eyona ngcamango isisiseko, izazinzulu zithi, kukuba ukucutha komkhenkce akulophawu nje lokufudumala kwehlabathi, kodwa kukwangumsebenzi oqhubayo emva kwawo.
"Ukususwa komkhenkce wolwandle kubhenca ulwandle olumnyama, oludala indlela enamandla yokuphendula," ingcali yokwakheka komhlaba uMarco Tedesco we-Earth Institute yeYunivesithi yaseColumbia uxelele i-AFP.
Kodwa xa indawo yesipili yatshintshwa ngamanzi aluhlaza okwesibhakabhaka, malunga nepesenti efanayo yamandla obushushu omhlaba afunxwa.
Asithethi ngommandla wesitampu apha: umahluko phakathi komndilili womkhenkce omncinane ukusuka ku-1979 ukuya ku-1990 kunye neyona ndawo iphantsi erekhodiweyo namhlanje ingaphezulu kwe-3 yezigidi zeekhilomitha zeekhilomitha – kabini elo laseFransi, eJamani naseSpain zidityanisiwe.
Iilwandle sele zifunxa i-90 yepesenti yobushushu obugqithisileyo obuveliswa yi-anthropogenic greenhouse gases, kodwa oku kuza kwiindleko, kubandakanywa utshintsho lweekhemikhali, amaza amakhulu okushisa olwandle kunye nezixhobo ze-coral ezifayo.
Inkqubo yemozulu entsonkothileyo yomhlaba iquka imisinga yolwandle edityanisiweyo neqhutywa yimimoya, amaza, noko kubizwa ngokuba yi<em>thermohaline circulation, yona ngokwayo eqhutywa kukutshintsha kweqondo lobushushu (“ukufudumala”) nokuxinana kwetyuwa (“brine”).
Kwanotshintsho oluncinci kwibhanti yokuhambisa yolwandle (ehamba phakathi kweepali kwaye ijikeleze omathathu amalwandlekazi) ingaba neziphumo ezibi kwimozulu.
Umzekelo, malunga neminyaka eyi-13,000 eyadlulayo, njengoko uMhlaba wawuguquka ukusuka kwixesha lomkhenkce ukuya kwixesha eliphakathi komkhenkce elivumela iintlobo zethu ukuba zichume, amaqondo obushushu ehlabathi ehle ngequbuliso amaqondo ambalwa ngokukaCelsius.
Ubungqina bokwakheka komhlaba bucebisa ukuba ukwehla kokujikeleza kwe-thermohaline okubangelwa kukungena kwamanzi abandayo abandayo asuka kwiArctic ngokuyinxalenye.
"Amanzi amatsha avela kulwandle olunyibilikayo kunye nomkhenkce osemhlabeni eGreenland aphazamisa kwaye anciphise iGulf Stream," inxalenye yebhanti yokuthutha ehamba e-Atlantic Ocean, umphandi uXavier Fettweiss weYunivesithi yaseLiege eBelgium.
Yiyo loo nto iNtshona Yurophu inemozulu epholileyo kunoMntla Merika kwindawo efanayo.”
Umkhenkce omkhulu osemhlabeni eGreenland ulahlekelwe ngaphezu kweetoni ezingama-500 eebhiliyoni zamanzi acocekileyo kulo nyaka uphelileyo, onke avuza elwandle.
Isixa serekhodi ngokuyinxenye kungenxa yokunyuka kwamaqondo obushushu, anyuka ngesantya esiphindwe kabini kwi-Arctic kunesijikelezi-langa siphela.
"Uphononongo oluninzi lubonise ukuba ukonyuka kwe-Arctic yasehlotyeni ngokuyinxenye kungenxa yobuncinci bomkhenkce wolwandle," u-Fettwiss uxelele i-AFP.
Ngokophononongo olupapashwe kwiphephancwadi leNdalo ngoJulayi, umzila wangoku wokutshintsha kwemozulu kunye nokuqala kwehlobo elingenaqhwa, njengoko kuchazwe yi-UN Intergovernmental Panel kwi-Climate Change Climate Panel, ingaphantsi kwe-1 yezigidi zeekhilomitha zeekhilomitha.ekupheleni kwale nkulungwane, ngokwenene iibhere ziya kufa yindlala.
"Ukufudumala kwehlabathi okubangelwa ngabantu kuthetha ukuba iibhere ze-polar ziba nomkhenkce omncinci kwaye omncinci wolwandle ehlotyeni," umbhali okhokelayo wophando uStephen Armstrup, isazinzulu esiyintloko kwi-Polar Bears International, uxelele i-AFP.