I-Antarctica lelona zwekazi lisemazantsi eMhlabeni, ligqunywe yingubo enomkhenkce efihla uthotho lweemfihlo zejoloji. Kutshanje, uhlolisiso luye lwabonisa ukuba kukho iintaba-mlilo ezingaphezu kwe-100 kweli lizwekazi, uninzi lwazo olwalungaziwa ngaphambili. Uphononongo olupapashwe kwi IZiko leSizwe leSayensi laseUnited States ibonisile ukuba I-18.000 iminyaka edlulileyo Ugqabhuko-dubulo olukhulu lwenzeka kwiNtaba yeTakahe, eyayinoxanduva lokuphelisa ixesha lokugqibela lomkhenkce. Ukuqonda ngcono ixesha le-geological ye-Antarctica, unokufunda malunga umdla malunga ne-Antarctica.
Iirekhodi zomkhenkce zibonise ukuba olu gqabhuko-dubulo lwalutyebile kwiihalogens, mhlawumbi ezibangele a umngxuma obalulekileyo kwi-ozone layer, ukuqala inkqubo ye ukuwohloka okukhawulezileyo. Iziphumo zezi ziganeko zentaba-mlilo zanda nakwimigama ye 2.800 km ukusuka kwindawo yogqabhuko-dubulo, ukufikelela kwiindawo eziphantsi kweTropiki.
Yintoni esinokuyilindela ukuba kunokuqhambuka intaba-mlilo engaphezulu kwesinye?
Imeko ibiya kuba mbi kakhulu ukuba iintaba-mlilo ezininzi bezinokudubula ngaxeshanye. Nangona amathuba okuba oku kwenzeke ephantsi, akunakwenzeka ngokupheleleyo. Ngaphakathi kwe-Antarctica, sifumana zombini iintaba-mlilo phezu komhlaba njengabanye iintaba-mlilo ezingaphantsi komkhenkce loo nto inokusebenza. Ukuba nokwenzeka kwe-a Umngxunya kuluhlu lwe-ozone okwenziwa kolu gqabhuko-dubulo ngumba obalulekileyo ofuna ukuqwalaselwa.
Ugqabhuko-dubulo olunobundlobongela lunokubangela a ukunyibilika ngokukhawuleza komphezulu, kwandisa ingozi yokuba nezinye iintaba-mlilo zingagqabhuka. Oku kunyibilika okukhawulezileyo kuya kuba negalelo nyusa amaqondo olwandle. Ulungelelwaniso lwemisinga yolwandle, olusasaza amaqondo obushushu ehlabathi, luya kuguqulwa, lungachaphazeli nje kuphela i-ikhosistim yolwandle kodwa namaqondo obushushu akuMazantsi eIkhweyitha kwaye okunokubakho nesijikelezi-langa siphela.
Le nto inokukhokelela ekubeni a Iziphumo zeDomino, apho kusekwe i-feedback loop: ukunyibilika okungakumbi kunokukhokelela kugqabhuko-dubulo, okuchaphazela kakhulu imozulu yehlabathi. Le meko yeyona nto ixhalabisayo, njengoko neentaba-mlilo ezingajongwa njengeentaba-mlilo ezinkulu zinokuyonakalisa ngequbuliso imozulu yehlabathi. Ngombono obanzi weziphumo zemozulu, jonga inqaku ukuba utshintsho lwemozulu lwangoku luya kuhlala ixesha elingakanani.
Uphando olutsha ngeentaba-mlilo e-Antarctica
Uphando lwakutsha nje lunike ukukhanya kubudlelwane obuntsonkothileyo phakathi komkhenkce onyibilikayo kunye nomsebenzi wentaba-mlilo. Isifundo esikhokelwa I-Coonin kwaye yapapashwa ngo I-Geochemistry, i-Geophysics, i-Geosystems ibonisa indlela ukulahleka komkhenkce ichaphazela i amagumbi magma afihliweyo. Ngu Ukulinganisa iikhompyutha ezingama-4.000, Abaphandi baye babonisa ukuba ukunciphisa uxinzelelo kula magumbi kunokunyusa nje kuphela ukuphindaphindeka kogqabhuko-dubulo, kodwa neyakhe ubukhulu.
Le ntshukumo sisiphumo se uxinzelelo lwe-lithostatic eyenziwa ngumkhenkce kuqweqwe loMhlaba, othi, xa unyibilika, uvumele i-magma ukuba yande. Le nkqubo inokuthatha amakhulu eminyaka ukuba yenzeke, kodwa amazinga okunyibilika okukhawulezileyo ngenxa yokutshintsha kwemozulu anyanzelwa ukuba abe lixesha elifutshane kakhulu, okonyusa umngcipheko wentshukumo yentaba-mlilo. Uphononongo lwakutsha nje kwi NONE Ikwaqaqambisa indlela utshintsho lwemozulu oluyichaphazela ngayo ijoloji yeendawo ezingekaphononongwa.
Umzekelo obalaseleyo walo msebenzi wentaba-mlilo ubekwe kwi IRift ekwiNtshona yeAntarctic, apho uninzi lwentaba-mlilo yelizwekazi igxile kakhulu. Iintaba-mlilo ezifana ne INtaba i-Erebus, eyaziwa ngokuba ichibi lava rhoqo, kunokuba iindawo ezibalulekileyo kule nkqubo. I ukunciphisa uxinzelelo kule mimandla kunokubangela uthotho lweziganeko zentaba-mlilo. Le nto iye yabonwa nakwezinye iindawo zehlabathi, ichaphazela ijografi yabo.
Ugqabhuko-dubulo olungabonakaliyo kodwa olubalulekileyo
Nangona ugqabhuko-dubulo olungaphantsi komkhenkce lusilela ukungena kumphezulu, impembelelo yalo inkulu. Yena ubushushu obuphumayo I-Magma inokunyibilikisa umkhenkce ukusuka kwisiseko, ngaloo ndlela yenza buthathaka iileya eziphezulu kunye nokukhawulezisa ukuwa kwee-glaciers. Into eyaziwa ngokuba yi-a iyakhiwa ivolcanic-glacial feedback loop: Ukunyibilika komkhenkce kubangela ukuphuma koxinzelelo kwiintaba-mlilo, nto leyo eyenza ubushushu obungakumbi kwaye ikhawulezise ukunyibilika. Ukuqonda ngcono iziphumo zale mijikelo, kuluncedo ukufunda malunga ne Ukuphela kwePermian kunye nezifundo zayo malunga nemozulu.
Le nto sele ibonwe kweminye imimandla, njengaseIceland, apho ugqabhuko-dubulo luye lwabangela ukunyibilika ngokukhawuleza komkhenkce kunye nezikhukula ezinkulu ezibizwa ngokuba jökulhlaups. E-Antarctica, ukuqokelelana kogqabhuko-dubulo olungaphantsi komkhenkce okuphindaphindiweyo kunokwandisa kakhulu ilahleko yomkhenkce. Nokuba ugqabhuko-dubulo oluncinane oluphindaphindwayo ekuhambeni kwexesha lubonakaliswe ukuba lunempembelelo enkulu kwiipateni zemozulu yehlabathi.
Ugqabhuko-dubulo alupheleli nje ekubeni negalelo ekunyibilikeni komkhenkce; Zikwachaphazela i uzinzo lwesakhiwo ukusuka kumkhenkce. Oku kuyakhathaza ngakumbi kwimimandla efana noLwandle lwase-Amundsen, apho umkhenkce sele uhlehla kwaye unokufikelela kwindawo yokungabuyi kumashumi eminyaka ezayo.
Indlela impembelelo eyalinganiswa ngayo
Ukulinganisa le mingcipheko, iqela likaCoonin liphuhlise imodeli ye-thermomechanical. Le modeli ilinganisa indlela i amagumbi magma Basabela kumazinga ahlukeneyo okulahleka kweqhwa, ngokuqwalasela izinto ezifana nobunzulu bamagumbi, ubungakanani be-magma kunye neegesi ezinyibilikayo. Iziphumo zibonisa ukuba izinga lokunyibilika libalulekile: ukunyibilika ngokuthe ngcembe kuvumela amagumbi ukuba alungelelanise, ngelixa ukunyibilika ngokukhawuleza kwandisa amathuba okuqhuma.
Ngokutsho kwabaphandi, a uxinzelelo olubalulekileyo lokukhupha kunokuvusa iziganeko ezongezelelekileyo zodubulo. Oku kuthetha ukuba isantya sokunyibilika sibaluleke njengomlinganiselo opheleleyo womkhenkce olahlekileyo. Kwezona meko zinzima kakhulu, ukonyuka okubalulekileyo kwentshukumo yentaba-mlilo kunokulindelwa kumashumi eminyaka ezayo ukuba amaqondo obushushu ehlabathi ayaqhubeka nokunyuka. Oku kudala imeko-bume yejoloji eyahlukileyo enokufundwa kwizifundo ezizayo.
Nangona inkqubo yokunyibilika iphazamiseka, imiphumo kumagumbi e-magma inokuqhubeka iinkulungwane, kuba ukunciphisa uxinzelelo kuguqula ngokusisigxina ukubunjwa kunye nokuziphatha kwe-magma, ukwandisa amandla ayo okubangela ukuqhuma okukhulu kwixesha elizayo.
Iimpembelelo zexesha elide kunye nemingeni yexesha elizayo
Olu phononongo, oluqaqambisa unxulumano phakathi kwentaba-mlilo engaphantsi komkhenkce kunye nokutshintsha kwemozulu yehlabathi, luphakamisa inkxalabo ebalulekileyo. Phakathi kwezona ziphumo zoyikekayo zi Ukunyuka kwamaqondo olwandle. Ukuwa komkhenkce e-Antarctica kunokunyusa ulwandle ngeemitha eziliqela, nto leyo ebeka izigidi zabantu emhlabeni wonke emngciphekweni. Ukongezelela, iigesi zentaba-mlilo ezikhutshelwa kwi-atmosfera zinokuwenza abe shushu ngakumbi umhlaba. Ukuba ufuna ukwazi ngakumbi malunga nendlela utshintsho lwemozulu oluqikelelwayo, oku inqaku malunga noMars inokukunika imbono ebangel’ umdla.
Nangona kunjalo, ezi zinto zifunyanisiweyo zikwabonelela ngefestile kwi-Antarctica geological past. Ngexesha lomkhenkce wokugqibela, eli lizwekazi laligqunywe yimikhenkce engqindilili. Ngoko ke, kunokwenzeka ukuba iinkqubo ezifanayo zenzeka kwixesha elidlulileyo, ezibangela ugqabhuko-dubulo oluye lwaba negalelo ekunyibilikeni komkhenkce kumaxesha angaphambili. Ukufunda ezi ziganeko zembali kunokusinceda ukuba siqikelele ukuba iinkqubo zentaba-mlilo ziya kusabela njani kutshintsho lwemozulu lwangoku.
Kubalulekile ukuqinisa ukujonga iintaba-mlilo ze-Antarctic. Ukusetyenziswa kobuchwepheshe obunje irada yokungena kumkhenkce kunye neemodeli eziphambili zenyikima zinokubonelela ngedatha ebalulekileyo ukuqonda ngcono olu nxibelelwano phakathi komkhenkce kunye ne-magma. I-Antarctica, kunye neemfihlakalo zayo zokwakheka komhlaba ezingafunyaniswanga, zinokudlala indima ephambili ekuqondeni kwethu ikamva lesijikelezi-langa.
I-Antarctica imele i-labyrinth yamathuba kunye nokungaqiniseki. Kwisanti yexesha, iintaba-mlilo zayo zisenokuba ziye zalala kumkhenkce omkhulu, kodwa utshintsho lwemozulu lubangela ukuba zenzeke. utshintsho olukhulu ezifuna ingqalelo yehlabathi.