NgoSepthemba 2023, amagagasi okuzamazama komhlaba afanayo aqoshwa ezikhungweni emhlabeni wonke athatha izinsuku eziyisishiyagalolunye. Lawa magagasi okuzamazama komhlaba ayengafani kakhulu namagagasi adalwa ukuzamazama komhlaba noma intaba-mlilo yingakho ukuthi akhiwa kanjani ayaziwa kuze kube muva nje. Ucwaningo lwakamuva luthole ukuthi ukudilika komhlaba okukhulu okubangelwe ukushintsha kwesimo sezulu kudale i-tsunami enkulu endaweni eqhelile yaseDickson Fjord empumalanga yeGreenland. Ukudlidliza okukhiqizwa ukugeleza kwe-tsunami emuva naphambili kuyo yonke i-fjord kwaqoshwa emhlabeni wonke njengamaza e-monochromatic seismic ahlala isikhathi eside ngonyaka odlule.
Ukuzamazama komhlaba kudala amaza okuzamazama komhlaba amafrikhwensi ahlukahlukene (okuxubile) esikhathi esifushane. Ubude besikhathi eside amaza okuzamazama komhlaba athatha imizuzu noma amahora ayaziwa ukuthi ahlotshaniswa nezintaba-mlilo.
Ngomhla ziyi-16 kuSepthemba 2023, ama-seismometers emhlabeni wonke aqopha amaza okuzamazama afana ne-monochromatic efrikhwensi eyodwa athatha izinsuku eziyisishiyagalolunye ezigcwele. Lezi zimpawu zazivela eMpumalanga Greenland kodwa azikwazanga ukuthi zibangelwe ukuzamazama komhlaba ngenxa yokuthi zazingezona zamaza axubile. Lezi zimpawu zokuzamazama komhlaba azikwazanga ukuba ngenxa yokuphazamiseka kwentaba-mlilo ngoba zahlala isikhathi eside kunamagagasi akhiqizwa izintaba-mlilo. Njengoba ukwakheka kwala magagasi okuzamazama komhlaba kungachazwanga, ahlukaniswa njenge-USO (into engaziwa yokuzamazama komhlaba).
Abacwaningi manje sebethole ukuthi la magagasi okuzamazama komhlaba ayinqaba akheka kanjani.
Lisebenzisa amathuluzi ahlukahlukene e-geophysical kanye nezifundo zokulingisa, ithimba labacwaningi lithole ukuthi i-rockslide enkulu eqalwe ukuncibilika kweqhwa ngenxa yokushintsha kwesimo sezulu kwakuyisiqalo. I-avalanche enkulu ye-rock-ice engu-25 × 106 cubic metres ungene ku-Dickson Fjord. Lesi sifunda sikude kakhulu, futhi umcimbi awubonwanga muntu.
I-avalanche enkulu e-fjord iholele ekwakhekeni kwe-tsunami engamamitha angu-200 ukuphakama eyazinza yaba igagasi lokuma lesikhathi eside elingamamitha angu-7 ukuphakama. Ama-Fjords anezindonga eziphakeme zamatshe nhlangothi zombili. Ukuhlehla emuva naphambili kwamagagasi aphezulu ku-fjord kukhiqize ukudlidliza okusabalele emhlabeni wonke njengamagagasi okuzamazama obude besikhathi eside be-monochromatic.
Ngakho, uchungechunge lwezenzakalo lwaqala ngokubhidlika okukhulu komhlaba. Ukufudumala kwembulunga yonke kanye nokushintsha kwesimo sezulu kunomthelela ekuncibilikeni kweqhwa ezindaweni ezimaphakathi nezwe okubuye kuxhumene nokudilika kwenhlabathi okukhulu. Lolu cwaningo lugqamisa imiphumela eyehlayo yokushintsha kwesimo sezulu ukuthi ulwandle noqweqwe lomhlaba kuthonywa kanjani izehlakalo ezifundeni zeqhwa.
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References:
- Svennevig K., et al 2024. I-tsunami ekhiqizwe yi-rockslide ku-fjord yaseGreenland yaduma eMhlabeni izinsuku eziyi-9. ISAYENSI. 12 September 2024. Vol 385, Issue 6714 pp. 1196-1205. I-DOI: https://doi.org/10.1126/science.adm9247
- Izindaba ze-UCL - Ukudilika komhlaba okubangelwe ukuguquguquka kwesimo sezulu kubangele uMhlaba ukundindizela izinsuku eziyisishiyagalolunye. Ishicilelwe ngomhla ka-13 Septhemba 2024. Itholakala e- https://www.ucl.ac.uk/news/2024/sep/climate-change-triggered-landslide-caused-earth-vibrate-nine-days
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