Ithonya Le-Indian Ocean Dipole Phenomenon Esimweni Solwandle lwase-Indonesia
I-Indonesia yaziwa njengezwe elikhulu kunawo wonke emhlabeni elinezindawo zasolwandle ezinkulu neziyinkimbinkimbi. Izimo zasolwandle zase-Indonesia azithonywa nje kuphela yizici zendawo ezifana nezimvula ezinkulu, imisinga yolwandle, kanye nezici zendawo zesiqhingi, kodwa futhi nayizehlakalo zesimo sezulu somhlaba wonke nezesifunda. Izehlakalo ezibalulekile ezidlala indima ebalulekile yi-Indian Ocean Dipole (IOD). Lesi sehlakalo sivame ukunganakwa umphakathi uma siqhathaniswa ne-El Niño–La Niña, yize umthelela waso emanzini ase-Indonesia—ikakhulukazi ezindaweni ezisentshonalanga naseningizimu—ubaluleke kakhulu.
Iyini i-Indian Ocean Dipole?
I-Indian Ocean Dipole iyisimo sokushintshashintsha kwezinga lokushisa lolwandle (SST) e-Indian Ocean okwenzeka ngesimo se-"dipole," noma umehluko ekungajwayelekile kwezinga lokushisa phakathi kwezifunda ezimbili eziyinhloko: i-Indian Ocean entshonalanga (eduze ne-East Africa) kanye ne-Indian Ocean empumalanga (eduze ne-Indonesia, ikakhulukazi i-Sumatra ne-Java). I-IOD inezigaba ezimbili eziyinhloko:
1. I-IOD Enhle: Amazinga okushisa olwandle entshonalanga ye-Indian Ocean afudumele kunokujwayelekile, kanti ingxenye esempumalanga (eduze ne-Indonesia) ipholile kunokujwayelekile.
2. I-Negative IOD: Isimo esiphambene nalokho, ingxenye esempumalanga ifudumele kunokujwayelekile kanti ingxenye esentshonalanga ibanda kakhulu.
Lo mehluko wokufudumala uthinta amaphethini omoya, ukwakheka kwamafu, kanye nokusabalala kwemvula. Nakuba uqala ngomehluko emazingeni okushisa olwandle, imiphumela ye-IOD idlulela emkhathini futhi ithinta izimo zolwandle ezindaweni zasolwandle zase-Indonesia.
Indlela ye-IOD kanye nobudlelwano bayo namanzi ase-Indonesia
Uma kwenzeka i-IOD, izinhlelo zomoya kanye namanje e-Indian Ocean ziyashintsha. Ngesikhathi sesigaba se-IOD esihle, imimoya ivame ukuqina kusukela empumalanga kuya entshonalanga eduze kwe-equator ye-Indian Ocean. Le mimoya isunduza amanzi afudumele kude namanzi ase-Indonesia iye entshonalanga. Ohlangothini olusempumalanga (eduze ne-Indonesia), amanzi afudumele angaphezulu ayasuswa bese ethathelwa indawo ngamanzi apholile avela ngaphansi komhlaba ngokusebenzisa ulwelwesi oluphezulu.
Ngakolunye uhlangothi, ngesikhathi sesigaba se-IOD esingesihle, imimoya iba buthaka noma ishintshe indlela, okubangela amanzi afudumele "ukucwila" empumalanga ye-Indian Ocean. Ngenxa yalokho, amanzi aseduze ne-Indonesia aba afudumele, avumela kakhulu ukwakheka kwamafu emvula.
Ithonya le-IOD emazingeni okushisa olwandle e-Indonesia
Omunye wemiphumela eqondile kakhulu ye-IOD ezimweni zasolwandle zase-Indonesia ukushintsha kwamazinga okushisa olwandle, ikakhulukazi ezindaweni ezilandelayo:
– Amanzi aseNtshonalanga yeSumatra
– I-Sunda Strait
- Amanzi aseNingizimu yeJava kuya eNusa Tenggara
– Ulwandle i-Indian eningizimu ye-Indonesia
Ngesikhathi se-IOD enhle, amazinga okushisa olwandle kulezi zifunda avame ukwehla. Lokhu kwehla kubonakala ngokucacile ekubonweni kwesathelayithi, ikakhulukazi ngesikhathi se-IOD ephezulu, evame ukwenzeka phakathi kukaJulayi noNovemba. Ukupholisa kolwandle akuyona nje indaba yokushisa; kuthinta nezinqubo zezinto eziphilayo nezamakhemikhali emanzini, okuhlanganisa ukusatshalaliswa kwe-plankton, umkhiqizo wokudoba, kanye nenduduzo yezindawo zokuhlala zezinto eziphilayo zasolwandle.
Uma i-IOD ingekho esimweni esihle, amazinga okushisa olwandle avame ukukhuphuka. Lokhu kufudumala kungabangela izinguquko zemvelo, kwandise ukucindezeleka kokushisa ezitsheni zamakhorali, futhi kwezinye izimo kunegalelo ekukhanyeni kwamakhorali uma kuqhubeka isikhathi eside futhi kuhlanganiswe nokufudumala komhlaba.
Umthelela we-IOD emifuleni yolwandle kanye nasogwini oluphezulu
Amanzi aseningizimu yeJava kanye neNusa Tenggara ayaziwa ngokukhuphuka okukhulu kwesizini, ikakhulukazi ngesikhathi semvula yasempumalanga (cishe ngoJuni-Septhemba). I-IOD ingaqinisa noma inciphise le nqubo.
– I-IOD enhle ivame ukuqinisa ukukhukhumala eningizimu yeJava–Bali–Nusa Tenggara ngoba imimoya eqinile isunduza amanzi angaphezulu ogwini. Ngenxa yalokho, amanzi abandayo, acebile ngezakhamzimba akhuphukela phezulu.
– I-IOD engemihle ivame ukwenza buthaka ukukhukhumala kwamanzi, ngoba ukuqongelela kwamanzi afudumele empumalanga kwenza ukuhlukaniswa kwamanzi kuqine kakhulu (ungqimba olufudumele olungenhla luyamelana nokuxubana), okwenza kube nzima kakhulu ukuthi izakhamzimba zikhuphukele phezulu.
Izinguquko ekukhuphukeni kwamanzi zibaluleke kakhulu ngoba zihlobene ngqo nokuvunda kwamanzi kanye nokutholakala kokudla kochungechunge lokudla lwasolwandle.
Umthelela ekukhiqizweni kokudoba
Lapho ukukhukhumala kukhula (ngokuvamile ngezikhathi ze-IOD ezinhle), izakhamzimba ezifana ne-nitrate ne-phosphate ezivela ezingqimbeni ezijulile zilethwa phezulu. Lezi zakhamzimba zisheshisa ukukhula kwe-phytoplankton, okwandisa ubuningi be-zooplankton nezinhlanzi ezincane. Lokhu kungagcina kuthinte ukudoba okubanjwe.
Kwamanye amanzi aseningizimu yeJava neNusa Tenggara, i-IOD enhle ingahlotshaniswa nokwanda komkhiqizo wezindawo zokudoba ezithile ze-pelagic ngenxa yokutholakala kokudla okuphezulu. Kodwa-ke, umthelela awuhlali ufana. Izimo zolwandle ezipholile kanye nemimoya enamandla nakho kungandisa amagagasi kanye nengozi yokuya olwandle, okungaba nomthelela omubi kubadobi abancane naphezu kokwanda kwamandla okudoba.
Okwamanje, i-IOD engemihle, evame ukuholela emanzini afudumele futhi inciphise ukukhukhumala kwamanzi, inganciphisa umkhiqizo oyinhloko. Ngaphansi kwezimo ezithile, izinhlanzi zingafuduka ziyofuna amanzi afaneleka kakhudlwana, okushintsha amaphethini okudoba futhi kuthinte imali engenayo yabadobi.
Umthelela we-IOD emagagasini kanye nesimo sezulu sasolwandle
Ngaphezu kokuthonya amazinga okushisa olwandle kanye nemisinga, i-IOD iphinde ithinte imimoya kanye nokwakheka kwezinhlelo zesimo sezulu phezu kwamanzi ase-Indonesia. Ngesikhathi se-IOD enhle, intshonalanga kanye neningizimu ye-Indonesia zivame ukoma, kanye nokwakheka kwamafu emvula anciphile. Imimoya yase-Easter ingaba namandla kakhulu, okungenzeka ikhulise ukuphakama kwamagagasi emanzini avulekile oLwandlekazi i-Indian oluseningizimu.
Lo mthelela ubalulekile emisebenzini yokuthutha imikhumbi, ukuphepha kwabadobi, kanye nokusebenza kwechweba. Amagagasi aphezulu eningizimu yeJava, eBali, nase-East Nusa Tenggara (NTT) anganda ngezikhathi ezithile, okudinga ukuqapha kanye nezixwayiso zakuqala ezivela ezinhlanganweni ezifanele.
Ngesikhathi se-IOD engemihle, amathuba okwakheka kwamafu nemvula ayanda emanzini azungeze intshonalanga ye-Indonesia. Lesi simo singandisa ukwanda kwesimo sezulu esibi, okuhlanganisa imvula enkulu, iziphepho zendawo, kanye nokungabonakali kahle olwandle, okuphinde kube yingozi ekuthuthweni olwandle.
Ukusebenzisana kwe-IOD ne-El Niño ne-La Niña
I-IOD ivame ukwenzeka kanye noma isebenzisana ne-ENSO (El Niño–Southern Oscillation) eLwandlekazini iPacific. Ukuhlanganiswa kwalokhu okubili kungakhulisa noma kunciphise umthelela e-Indonesia.
– I-El Niño + IOD enhle ivame ukukhulisa isomiso e-Indonesia futhi yandise amathuba okupholisa empumalanga ye-Indian Ocean eduze ne-Indonesia. Imiphumela ingazwakala ngesimo sezinkathi ezinde zesomiso, ingozi yemililo yamahlathi, kanye nezinguquko ezimweni zolwandle.
– I-La Niña + i-IOD engemihle ivame ukwandisa imvula futhi yenze amanzi afudumale entshonalanga ye-Indonesia, okungandisa ingozi yezikhukhula zasogwini kwezinye izindawo futhi kuthinte ikhwalithi yamanzi ngenxa yokugeleza komhlaba.
Ngakho-ke, ukuqonda i-IOD akukwazi ukuhlukaniswa nokuqapha ezinye izimo zesimo sezulu.
Imiphumela yokuphathwa kolwandle lwase-Indonesia
Umthelela we-IOD ezimweni zolwandle lwase-Indonesia ubonisa ukubaluleka kwezinhlelo zokuqapha ulwandle kanye nesimo sezulu eziqinile. Idatha yesathelayithi, ama-buoy olwandle, kanye namamodeli okubikezela isimo sezulu kungasiza ekubaleni izingozi namathuba, njengalawa:
- Ukunqunywa okuphumelelayo kwezinkathi zokudoba nezindawo zokudoba
- Isexwayiso sangaphambi kwesikhathi samagagasi aphezulu kanye nesimo sezulu esibi kakhulu ngokuphepha kokuthunyelwa kwemikhumbi
– Ukuvikelwa kwezindawo zemvelo ezibucayi njengemifula yamakhorali kanye nemibhede yotshani basolwandle
– Lindela izinguquko ekukhiqizweni kolwandle ezithinta umnotho wasogwini
Njengoba isimo sezulu sishintshashintsha ngenxa yokufudumala komhlaba, izehlakalo ze-IOD ezimbi kakhulu zingase zibe zivamile noma zibe zimbi kakhulu, okwenza ukuzivumelanisa nezimo okusekelwe kwisayensi kube yinto ebalulekile.
Isiphetho
I-Indian Ocean Dipole iyinto yesimo sezulu solwandle esithinta kakhulu izimo zasolwandle e-Indonesia, ikakhulukazi ezindaweni ezisentshonalanga naseningizimu ezigudle uLwandlekazi i-Indian. Ngokushintsha kwamazinga okushisa olwandle, amaphethini omoya, imisinga, kanye nokuqina kokuphakama, i-IOD ingathonya umkhiqizo wokudoba, amagagasi, kanye nesimo sezulu sasolwandle. Imiphumela yayo ingaba wusizo ngesimo sokwanda kwezakhamzimba kanye nokubamba ngezikhathi ezithile, kodwa futhi ingaba nezingozi ezifana namagagasi aphezulu, izinguquko zemvelo, kanye nokungaqiniseki kwemiphakathi yasogwini.
Ngakho-ke, ukuqonda i-IOD kanye nokuhlanganiswa kwayo nezinqubomgomo zokudoba olwandle, ezokudoba kanye nokunciphisa izinhlekelele kuyisinyathelo esibalulekile ekugcineni ukuqina kolwandle lwase-Indonesia phakathi kwezinguquko zesimo sezulu ezishintsha njalo.
