Njengoba amazinga okushisa embulunga yonke eqhubeka ekhuphuka, ulwandle olubandayo olunenkani luye lwakhuphuka eNyakatho ye-Atlantic osekuyiminyaka ludida ososayensi. Lona "umgodi" wokufudumala eNyakatho ye-Atlantic, eyaziwa nangokuthi Ibhuloho Elibandayo. Kule minyaka eyikhulu edlule, amazinga okushisa embulunga yonke akhuphuke ngesilinganiso esingu-1°C, kuyilapho imbobo efudumele eningizimu yeGreenland iphole ngo-0,9°C.
Kulesi sihloko sizokutshela konke okudingeka ukwazi mayelana ne-Cold Blob, izici zayo kanye nocwaningo lwakamuva.
Ibhuloho Elibandayo
Ucwaningo lwangaphambili luhlobanise imbobo yokufudumala nemisinga yasolwandle eyenza buthaka eNyakatho ye-Atlantic eletha ukushisa okuvela ezindaweni ezishisayo. Ucwaningo olusha olushicilelwe kumagazini iNature Climate Change luphakamisa lokho Kuhileleke nezinye izici. Lokhu kuhlanganisa izinguquko ekuhambeni kolwandle ezindaweni eziphakeme kanye nolwandle olupholile olukhiqiza amafu asezingeni eliphansi.
Izinguquko zibangelwa ngokucacile ukuphoqelelwa kwe-anthropogenic ekufanisweni kwemodeli yesimo sezulu futhi zibalulekile ekuqondeni ukuguquguquka kwangaphambilini nokuzayo kwembobo yokufudumala.
Amamephu amaningi okushintsha kwezinga lokushisa komhlaba abonisa amabhande abomvu nawowolintshi, agqamisa ukufudumala endaweni enkulu yomhlaba. Kodwa ezinye izindawo azifudumalanga kakhulu futhi sezize zaphola. Enye yalezo zindawo iyindawo eseNyakatho ye-Atlantic Ocean.
Lo mgodi wokufudumala ucace kakhulu embikweni wakamuva wokuhlola we-Intergovernmental Panel on Climate Change njengendawo eluhlaza okwesibhakabhaka kumephu, okuyinto ikhombisa ukukhuphuka okuphawuliwe kwesilinganiso sokushisa komhlaba wonke kusukela ngo-1901 kuya ku-2012.
Ucwaningo olusha
Ucwaningo luye lwabonisa ukuthi imbobo yokufudumala ixhunyaniswe nokuba buthakathaka kwe-Atlantic Meridional Overturning Circulation (AMOC), uhlelo lwemisinga yolwandle e-Atlantic ehambisa amanzi afudumele ukusuka ezindaweni ezishisayo futhi ngaphesheya ukuya eYurophu.
I-AMOC iyingxenye yenethiwekhi enkulu yamamodeli okujikeleza olwandle emhlabeni jikelele. ezinyakazisa ukushisa emhlabeni wonke. Iqhutshwa ukupholisa nokucwila kwe-brine ezindaweni eziphakeme ze-North Atlantic.
Ucwaningo lubonisa ukuthi i-AMOC iye yaba buthaka kusukela phakathi nekhulu lama-XNUMX (futhi mhlawumbe isikhathi eside) ngenxa yokungena kwamanzi ahlanzekile eNyakatho ye-Atlantic kusukela ekuncibilikeni kweqhwa laseGreenland kanye nokukhuphuka kwamazinga okushisa olwandle kanye nemvula endaweni.
La manzi ahlanzekile engeziwe anciphisa ukuncipha kwamanzi olwandle apholisayo, okubuye kunciphise inani lamanzi afudumele akhiwa ezindaweni ezishisayo, okwenza kube buthaka ukujikeleza kwamanzi.
Amanzi afudumele kancane ezindaweni ezishisayo anomphumela wokupholisa eNyakatho ye-Atlantic, eqeda ukufudumala okuvamile kolwandle ekukhuphukeni kwamazinga okushisa omhlaba. Ngenxa yalokho, imbobo efudumele ibangelwa ikakhulukazi ukwehla kwe-AMOC. Nokho, ucwaningo lukhombisa ukuthi lokhu kungenye yezici eziningi ezinomthelela ekupholiseni kolwandle nomkhathi.
Ukushisa kwe-cavity nokushintsha kwesimo sezulu
Ukucacisa ubudlelwano phakathi kokushisisa komgodi, i-AMOC, nokushintsha kwesimo sezulu, abacwaningi benze uchungechunge lwezivivinyo besebenzisa amamodeli wesimo sezulu. Kusethi yokuqala yokuhlola, abacwaningi baxhumanisa ukuthutha ukushisa kolwandle nokuguquguquka okujwayelekile kwesizini, basusa noma yikuphi ukuhluka kwesikhathi eside ukuze kugxilwe ikakhulukazi endimeni yomkhathi.
Bathola ukuthi uma kungekho zinguquko olwandle, imodeli isakhiqiza imbobo yokufudumala, nakuba ingekho ngendlela yokupholisa ngokuphelele, kodwa kunalokho ukufudumala okubuthakathaka.
Olunye ucwaningo luye lwabonisa ukuthi izinguquko zamafu zinomthelela omncane kodwa obonakalayo emigodini yokushisisa. Izilwandle ezibandayo zidala amafu asezingeni eliphansi, anciphisa imisebe yelanga engenayo futhi apholise ulwandle nakakhulu.
Ochungechungeni lwesibili lokuhlola, abacwaningi bagxile endimeni yokuthutha ukushisa kolwandle emgodini wokufudumala. Basebenzise imodeli eyodwa kuphela eyakhiwe yi-Max Planck Institute, kodwa basebenzise isethi yezifaniso eziyi-100 esikhathini esidlule kanye nezinye eziyi-100 zokulingisa iminyaka engu-150 esikhathini esizayo, lapho amazinga e-CO2 esemoyeni enyuke ngo-1% ngonyaka.
Lapha, njengasezifundweni ezedlule, abacwaningi bathola ukuthi iningi lembobo yokufudumala ihlobene nokujikeleza kolwandle. Ngokukhethekile, imiphumela ibonisa ukuthi ngenkathi iNyakatho ye-Atlantic ithola ukushisa okuncane okuvela ezindaweni ezishisayo, iphinde ilahlekelwe ukushisa okwengeziwe e-Arctic. Ukulingisa okuvela kule modeli kusikisela ukuthi ukunyuka kokushisa kolwandle kusuka ezindaweni eziphakeme zaseNyakatho ye-Atlantic kungenxa yengxenye yokuqiniswa kokujikeleza kwe-subpolar, okusabalalisa kabusha ukushisa ngokuvundlile.
Lokhu kusakazwa kwe-subpolar kuyiphethini yokujikeleza okuphambene newashi emanzini angaphezulu oLwandlekazi i-Atlantic Ocean. Izizathu zokuqiniswa kokujikeleza ziyinkimbinkimbi.. Kafushane, nokho, lezi zinguquko empeleni zibangelwa ukukhishwa kwabantu kwamagesi abamba ukushisa.
Umthelela womuntu ku-Cold Blob
Lawa ma-ensembles amakhulu enza kube lula kakhulu ukuhlukanisa imiphumela yokushintsha kwesimo sezulu emashumini eminyaka emvelo edlule naleyo yokuphoqelela isimo sezulu okubangelwa umthelela womuntu. Empeleni, Ezifanisweni zokugcina eziyi-100 zokushisisa, ucwaningo luthole ukuthi zonke zinembobo yokushisisa.
Okufana ngakho konke ukulingisa ukuthi ngokufudumala kwembulunga yonke kunokwanda kokuthunyelwa kokushisa ezindaweni eziphakeme. Lokhu kwanda kuchaza ngokuyinhloko ukwakheka kwezimbobo zokufudumeza futhi ngenxa yalokho kubangelwa amagesi abamba ukushisa akhishwa abantu.
Lokhu kusho ukuthi ngenkathi imbobo efudumele ingabhekwa ngokushintsha kwesimo sezulu okubangelwa abantu, futhi ukuba buthaka kwe-AMOC kungase kudlale indima ebalulekile ebukhoneni bayo. Kusho futhi ukuthi ukusetshenziswa kokushisa kwembobo ukuze kufinyelele amandla e-AMOC, njengoba kuye kwenzeka kwezinye izifundo, kufanele kwenziwe ngokuqapha, ngoba izinqubo ngaphandle kwe-AMOC zihilelekile futhi zenza ubuhlobo bube nzima.
Ngithemba ukuthi ngalolu lwazi ungafunda kabanzi mayelana ne-Cold Blob nezici zayo.