Ukufudumala kwembulunga yonke kubangela izinguzunga zeqhwa ukuncibilika kuwo wonke amazwekazi, kuhlanganise nase-Antarctica. Phambilini, izwe lase limbozwe yiqhwa ngokuphelele, kepha manje kunezindawo zomhlaba ezinamachibi nemifula engenalo iqhwa. Lezi zinqubo zenzeka ogwini lolwandle. Izithombe ezithathwe kuma-satellite, lapho ungabona khona ukukhululeka ngaphandle kweqhwa neqhwa, kuzosiza ukuqinisekisa lokhu.
Kungacatshangwa ukuthi izinguzunga zeqhwa ziyancibilika ngesikhathi sasehlobo, kepha izigodi ezingenalo iqhwa zinde kakhulu. Mhlawumbe, le ndawo inokushisa okufudumele okungavamile. Iqhwa elincibilikile lineqhaza ekwakhiweni kwemifula namachibi. Umfula omude kunayo yonke kuleli zwekazi yi-Onyx (30 km). Ugu lwayo alunalo iqhwa cishe unyaka wonke. Ngezikhathi ezahlukahlukene zonyaka, lapha kubonakala ukuguquguquka kwezinga lokushisa nokwehla kwezinga lamanzi. Isilinganiselo esiphelele sarekhodwa ngo-1974 ku- +15 degrees Celsius. Azikho izinhlanzi emfuleni, kodwa kukhona ulwelwe nezilwanyana ezincane.
Kwezinye izingxenye ze-Antarctica, iqhwa selincibilikile hhayi nje kuphela ngenxa yokunyuka kwamazinga okushisa nokushisa komhlaba, kepha futhi ngenxa yenqwaba yomoya ehamba ngejubane elihlukile. Njengoba ukwazi ukubona, impilo kuleli zwekazi akuyona eyindilinga, kanti i-Antarctica ayigcini nje ngokuba yiqhwa neqhwa, kunendawo yokufudumala kanye nezindawo zokugcina amanzi.
Amachibi ama-oases
Esikhathini sehlobo, izinguzunga zeqhwa ziyancibilika e-Antarctica, futhi amanzi agcwalisa izingcindezi ezahlukahlukene, ngenxa yalokho okwakhiwa amachibi. Eziningi zazo zirekhodwe ezindaweni ezisogwini, kepha futhi zitholakala ezindaweni eziphakeme kakhulu, ngokwesibonelo, ezintabeni zeNdlovukazi Maud Land. Ezwenikazi, kunamachibi amakhulu namancane endaweni. Ngokuvamile, amachibi amaningi atholakala kuma-oase ezwekazini.
Ngaphansi kwamachibi e-ice
Ngaphezu kwamanzi angaphezulu, amadamu angaphansi komhlaba atholakala e-Antarctica. Zitholwe kungekudala. Maphakathi nekhulu lamashumi amabili, abashayeli bezindiza bathola ukwakheka okungaziwa kuze kufike kumakhilomitha angama-30 ukujula kuze kufike kumakhilomitha ayi-12 ubude. Lawa machibi nemifula engaphansi kwe-subglacial aphenywa ngososayensi abavela ePolar Institute. Kulokhu, kusetshenziswe ucwaningo lwe-radar. Lapho kwaqoshwa khona amasiginali akhethekile, kwatholakala ukuncibilika kwamanzi ngaphansi kweqhwa. Ubude obulinganiselwa bezindawo zamanzi angaphansi kweqhwa bangaphezu kwamakhilomitha ayi-180.
Ngesikhathi kwenziwa izifundo zamachibi angaphansi kweqhwa, kwatholakala ukuthi avela kudala. Amanzi ancibilikayo izinguzunga zeqhwa zase-Antarctica agelezela kancane kancane ezinqolobaneni ezingaphansi komhlaba, evela ngenhla embozwe yiqhwa. Amachibi amancane nemifula aneminyaka ecishe ibe yisigidi ubudala. Kukhona udaka ezansi kwawo, futhi izinhlamvu, impova yezinhlobo ezahlukahlukene zezitshalo, ama-microorganisms eziphilayo angena emanzini.
Ukuncibilika kweqhwa e-Antarctica kwenzeka ngenkuthalo endaweni yezinguzunga zeqhwa. Ziwumfudlana osheshayo weqhwa. Melt amanzi agelezela kancane olwandle futhi ingxenye abe yiqhwa ebusweni beqhwa. Inqubo yokuncibilika kwekhava leqhwa ibonwa kusuka kumasentimitha ayi-15 kuye kwangama-20 minyaka yonke endaweni yasogwini, nasenkabeni - kuze kufike kumasentimitha ama-5.
IChibi iVostok
Omunye wamanzi amakhulu kunawo wonke ezwekazini, ongaphansi kweqhwa, yiLake Vostok, njengesiteshi sesayensi e-Antarctica. Indawo yayo cishe ingamakhilomitha ayizinkulungwane eziyi-15.5. Ukujula ezingxenyeni ezihlukene zamanzi kuhlukile, kepha ubukhulu obuqoshwe kumamitha ayi-1200. Ngaphezu kwalokho, kukhona okungenani iziqhingi eziyishumi nanye endaweni yedamu.
Ngokuqondene nezilwanyana ezincane eziphilayo, ukwenziwa kwezimo ezikhethekile e-Antarctica kwaba nomthelela ekuhlukanisweni kwabo nezwe elingaphandle. Ngenkathi kuqalwa ukubhola ebusweni beqhwa laleli zwekazi, kwatholakala izidalwa ezahlukahlukene ekujuleni okukhulu, okuyisici sendawo yokuhlala kuphela. Ngenxa yalokho, ekuqaleni kwekhulu lama-21, kwatholakala imifula namachibi angaphezu kuka-140 ase-Antarctica.
