Ukuhlaziywa Kokuguquguquka Kwamanje Olwandle kusetshenziswa iphrofayili yamanje ye-Acoustic Doppler
I-Pendahuluan
Imisinga yolwandle iyisici esibalulekile sezinhlelo zolwandle, idlala indima ekuthuthweni kokushisa, usawoti, izakhamzimba, inhlabathi, kanye nokungcola. Ukuguquguquka kwamanje—kungaba kwansuku zonke, okwesizini, noma okweminyaka yonke—kuthinta ukuguquguquka kwemvelo yasogwini, ukuphepha kwemikhumbi, imisebenzi yolwandle, kanye nokuhlela olwandle. Ukuze uqonde ngokuphelele ukuziphatha kwamanje, kudingeka ukubonwa okukwazi ukubamba izinguquko zamanje ekujuleni okuhlukahlukene kanye nezilinganiso zesikhathi. Enye yezinsimbi ezisetshenziswa kakhulu kule njongo yi-Acoustic Doppler Current Profiler (ADCP), ithuluzi lokulinganisa lamanje elisekelwe ku-acoustic elingakwazi ukumaka amaphrofayili ejubane lamanje ngaphakathi kwekholomu yamanzi.
Lesi sihloko sixoxa ngomqondo wokuguquguquka kwamanje olwandle, izimiso zokusebenza ze-ADCP, izindlela zokuthola idatha nokucubungula, kanye nezindlela zokuhlaziya zokuhlonza amaphethini okuguquguquka kwamanje olwandle ngobuningi.
Umqondo Wokuguquguquka Kwamanje Olwandle
Ukuguquguquka komswakama wolwandle kubhekisela ezinguqukweni zesivinini samanje kanye nesiqondiso ngokuhamba kwesikhathi nendawo. Ngokuvamile, lokhu kuguquguquka kuthonywa yizimbangela eziningana eziyinhloko:
1. Ukujikeleza komoya kanye nobuso: Umoya ubangela imisinga engaphezulu ngokusebenzisa amandla okungqubuzana, kwakha imisinga yogu, ukukhuphuka/ukwehla, kanye nemisinga ye-Ekman.
2. Amagagasi: Ezindaweni eziningi ezisogwini, amagagasi ayingxenye eyinhloko ekhiqiza imisinga eshintshashintshayo ngezikhathi zansuku zonke noma zengxenye yansuku zonke.
3. Umehluko wobuningi (i-thermohaline): Izinga lokushisa kanye nosawoti okhanyayo kudala imisinga ye-baroclinic engahluka ngokwezinkathi zonyaka.
4. Amagagasi kanye nokuxhumana kwendawo: Izindawo eziseduze nogu, imifudlana emincane, kanye namanzi angajulile ngokuvamile abonisa imisinga eyinkimbinkimbi ngenxa yokusebenzisana kwemisinga nolwandle.
5. Izinguquko ezinkulu: Izenzakalo ezifana ne-ENSO, izimvula ezinkulu, noma i-Indonesian Throughflow (ITF) zingaguqula imisinga ngokwesifunda.
Ngenxa yokuthi lokhu kushintshashintsha kuvame ukwenzeka ngesikhathi esisodwa, ithuluzi lokuqapha kumele likwazi ukurekhoda imisinga ngokuqhubekayo, ngokuzinzile, nangokwezendlalelo (ezijulile). Yilapho ama-ADCP eba khona abalulekile.
Isimiso Sokusebenza se-ADCP
Ama-ADCP asebenza ngokusekelwe kumphumela we-Doppler, okuwukushintsha kwemvamisa yamagagasi e-acoustic abonakaliswa yizinhlayiya ezilengayo (isb., i-plankton noma i-sediment encane) emanzini. Ama-ADCP akhipha izimpawu ze-acoustic kumaza athile ngemishayo eminingi (ngokuvamile engu-3 noma engu-4), bese ethola izimpawu eziboniswayo. Umehluko wemvamisa phakathi kwezibonakaliso ezikhishwayo nezamukelwe ubalwa ukuze kutholakale ingxenye yejubane eceleni kokuqondisa kwemishayo.
Ngokuhlanganisa ulwazi oluvela emisebeni eminingi, i-ADCP ingalinganisa amavektha wamanje anezinhlangothi ezintathu (empumalanga-ntshonalanga, enyakatho-ningizimu, kanye nezingxenye eziqondile) ekujuleni okuhlukahlukene okuhlukaniswe ngamabhini (izendlalelo zokulinganisa). Umphumela uba iphrofayili yejubane lamanje kusukela eduze kwethuluzi kuya eduze kobuso noma phansi, kuye ngokucushwa kokufakwa.
Ngokuvamile kunezindlela ezimbili eziyinhloko zokufaka:
– Ifakwe phansi (ifakwe phansi): Ilinganisa ikholomu yamanzi ibheke phezulu (ibukeka ibheke phezulu), ifanele ukuqapha isikhathi eside.
– Kufakwe umkhumbi (ofakwe emkhunjini): Kukala imisinga esendleleni yokuhlola, efanelekela ukumepha indawo ngokushesha.
Umklamo Wokulinganisa Nokutholwa Kwedatha
Impumelelo yokuhlaziywa kokuguquguquka kwamanje incike kakhulu ekwakhiweni kokubuka. Amanye amapharamitha abalulekile okudingeka anqunywe yile:
1. Imvamisa kanye nobubanzi: Ama-ADCP emvamisa ephezulu (isb. 600–1200 kHz) afanelekela amanzi angajulile anesisombululo esiphezulu, kuyilapho amaza aphansi (isb. 75–300 kHz) afanelekela ukujula okukhulu.
2. Usayizi webhini kanye nesikhathi sokuhlola: Amabhini amancane anikeza ukulungiswa okungcono okuqondile, kodwa andise umsindo. Isikhathi sokuhlola esiqinile siyadingeka ukuze kuthathwe ukwehla nokugeleza kanye nokushintshashintsha okusheshayo, kodwa umthamo webhethri kanye nememori kumele kucatshangelwe.
3. Ubude bokubuka: Ukuze kuhlukaniswe izingxenye zokuma kolwandle kanye nezingezona ezokuma kolwandle, ukubuka kufanele kuthathe okungenani amasonto ambalwa; ukuze kuhlaziywe ngezikhathi ezithile zonyaka, kudingeka idatha yezinyanga.
4. Ukulungiswa kokuqondisa: Idatha yamanje idinga ulwazi lwesihloko, iphimbo, kanye nokugoqa (ikhampasi kanye nenzwa yokuthambekela) ukuze izingxenye zamanje ziguqulwe zibe uhlelo lokuxhumanisa lwendawo.
5. Ikhwalithi yedatha: Amapharamitha anjengokuhlobana kwesignali, iphutha lejubane, kanye nokuqina kokuzindla abalulekile ekuhloleni ikhwalithi yokulinganisa.
Ukucutshungulwa Kwedatha ye-ADCP: Izigaba Eziyinhloko
Ngaphambi kokuba kwenziwe ukuhlaziywa kokuguquguquka, idatha idinga ukudlula esigabeni sokucubungula ukuze imiphumela ibe ethembekile:
1. Ukulawulwa kwekhwalithi (QC)
- Susa idatha enokuxhumana okuphansi noma ijubane eliphezulu lamaphutha.
– Thola izinto ezingaphandle ngenxa yokuphazamiseka kwezinto eziphilayo, amabhamuza omoya, noma izimo zamagagasi amakhulu.
2. Ukulungiswa kwamagnetic kanye nokuguqulwa kokuxhumanisa
– Ukwehla kwamandla kazibuthe kungabangela ukuthambekela ohlangothini lwamanje uma kungalungiswanga.
– Idatha iguqulwa kusuka kuzixhumanisi zethuluzi/zomphetho kuya kuzixhumanisi ezisenyakatho-mpumalanga-eqondile.
3. Ukunqunywa kwebanga elingenalutho kanye nemingcele yobuso/isisekelo
– Eduze kwe-transducer kukhona indawo “engenalutho” engenakulinganiswa.
– Kumodi ebheka phezulu, idatha eseduze kobuso ingangcoliswa ukubonakaliswa kobuso (ukuphazamiseka kwe-side-lobe).
4. Ukunquma kanye nokuhlukaniswa kwesignali
– Izingxenye ze-Tidal zingahlukaniswa ngokusebenzisa ukuhlaziywa kwe-harmonic noma izihlungi (isb. i-low-pass ukuze kugqanyiswe ukuguquguquka kwe-subtidal).
Lesi sinyathelo siqinisekisa ukuthi isakhiwo sokuguquguquka esitholiwe empeleni sibonisa amandla olwandle, hhayi izinto zobuciko zemishini.
Indlela Yokuhlaziya Ukuguquguquka Kwamanje
Uma idatha isihlanziwe, ukuguquguquka kwamanje kungahlaziywa kusetshenziswa izindlela ezilandelayo.
1. Izibalo Eziyisisekelo kanye neRose Yamanje
Izibalo ezifana nesilinganiso, esiphezulu, ukuphambuka okujwayelekile, kanye nokusatshalaliswa kwesiqondiso kungachaza uhlamvu olujwayelekile lwamanje. I-rose yamanje ikhombisa izitayela eziqondisayo ezivelele kanye namaza azo.
2. Uchungechunge Lwesikhathi kanye ne-Energy Spectrum
Izakhi zochungechunge lwesikhathi ekujuleni okuningi zisiza ukubona izinguquko zamanje zansuku zonke noma zezikhathi ezithile (isb., ngenxa yeziphepho). Ukuze kutholakale izikhathi ezibusayo, kusetshenziswa ukuhlaziywa kwe-spectral (isb., i-FFT), okuvame ukukhombisa ukuphakama kwamandla ngesikhathi sezikhathi zolwandle (ngosuku/ngezikhathi ze-semidiurnal) noma zesimo sezulu.
3. Ukuhlukaniswa Kwezingxenye ze-Tidal kanye ne-Subtidal
Ezindaweni ezisogwini, imisinga yolwandle ivame ukuba namandla futhi ingafihla izimpawu zamanzi ezisele. Ukuhlaziywa kwe-Harmonic kungakhipha i-M2, S2, K1, O1, nezinye izingxenye. Okwamanje, izingxenye ze-subtidal (ezisele) zivame ukuhlotshaniswa nomoya, i-density gradients, noma ukujikeleza kwesifunda.
4. Ukuguquguquka Okuqondile: Ukwakheka Kwekholomu Yesiqeshana Neyamanzi
Inzuzo ye-ADCP yikhono layo lokubona ukwehluka kwamanje ngokujula. Ukuhlaziywa kwephrofayili kungaveza:
– Ukucheba okuqondile (ushintsho lwamandla kagesi ngokujula) kubalulekile ekuxubeni nasekuzinzeni kwekholomu yamanzi.
– Isendlalelo somngcele ongezansi sivame ukuba nemisinga ehamba kancane kanye nezinkomba ezahlukene ngenxa yokungqubuzana kwangaphansi.
– Imisinga enezingqimba ezimbili emigwaqweni noma emifudlaneni, isibonelo, ukungena kwamanzi ebusweni kanye nokuphuma kwamanzi ekujuleni.
5. Ukuhlaziywa Kwesizini kanye Nethonya Lesimo Sezulu
Ngedatha yesikhathi eside, amaphethini emvula noma izinguquko zesizini zingabonakala ezinguqukweni zemisinga eseleyo. Idatha yomoya kanye nomfutho womoya ingahlotshaniswa nemisinga engaphansi kwamanzi ukuze kuhlolwe ubudlelwano phakathi komkhathi kanye nokuguquguquka kolwandle.
Izinselele kanye nokulinganiselwa
Nakuba kunamandla kakhulu, ukusebenzisa i-ADCP kunemingcele ethile okudingeka icatshangelwe:
– Ukuphazamiseka kobuso (amagagasi, amabhamuza) kungonakalisa ikhwalithi yedatha eseduze kobuso.
– Ukuphazamiseka kwe-side-lobe kunciphisa ukujula okuthile okusebenzayo, ikakhulukazi emanzini angajulile.
– Ukuthambekela kwekhampasi kanye namaphutha okutsheka kungathinta isiqondiso samanje.
– Ukutholakala kwe-Scatterer: emanzini acwebezelayo kakhulu, ukubonakaliswa kungaba buthakathaka ukuze ukulinganisa kungazinzile.
Ngakho-ke, ukuqinisekiswa kusetshenziswa idatha esekelayo (isib. ama-tide gauges, idatha yomoya, ama-CTD, noma ama-drifter) kuvame ukudingeka ukuze kwandiswe ukuzethemba kokuchazwa.
Isiphetho
Ukuhlaziywa kokuguquguquka komsinga wolwandle kusetshenziswa i-Acoustic Doppler Current Profiler kunikeza indlela ephumelelayo yokuqonda ukuguquguquka kwamanje kokubili ngokwesikhathi nangokuqondile. I-ADCP ivumela ukubonwa kwephrofayili yamanje enesinqumo esiphezulu, okuvumela ukuhlukaniswa okucacile kanye nokuchazwa kwezingxenye zamaza, izinsalela, kanye nezakhiwo zezendlalelo zamanje. Ngokulawula ikhwalithi, ukulungiswa kokuqondisa, kanye nezindlela zokuhlaziya ezifana nokuhlolwa kwe-spectral, i-tidal harmonic, kanye nokwehliswa kwe-vertical, idatha ye-ADCP ingakhiqiza ulwazi olubalulekile locwaningo lwe-oceanographic, ukuphathwa kogu, ukuphepha kokuhamba, kanye nezidingo zemboni yezolwandle.
Ekugcineni, impumelelo yezifundo zokuguquguquka kwamanje ayixhomekile kuphela ethuluzini ngokwalo, kodwa futhi nasekuklanyweni okufanele kokubuka, ukucubungula idatha okuhlelekile, kanye nokuhumusha okucabangela izinqubo zomzimba zolwandle lwendawo. Uma lezi zici ezintathu zilingana, i-ADCP iba ngelinye lamathuluzi amahle kakhulu okuthola "ukushaya" kwemisinga yolwandle eshintsha njalo.
