“Mamiriro okunze ari kupenga” zvimwe ndiwo mashoko anotsanangura zvakarurama mamiriro okunze ari kuramba achioma atiri kuona. Gore negore, tinotsungirira kumwe kupisa kwakanyanya kwechirimo, asi tinotarisanawo netyisidziro yechando, kunaya kwemvura, uye njodzi dzinongoitika dzoga dziri kuramba dzichiwedzera kutyisa dzakadai semadutu nemadutu. Kwemakore akawanda, kwave kutaurwa nezvetembiricha inodziya zvisina kujairika muAtlantic, iyo yairatidzika kuva isingachinji. Nekudaro, zvakaonekwa zvichangobva kuitwa nemasayendisiti mumwedzi mitatu yadarika zvinoratidza maitiro anokatyamadza: Atlantic iri kutonhora chaizvo.
Muchikamu chino tichaudza iwe Ndeipi mhedzisiro ine kutonhora kweAtlantic kwava pedyo?.
The enigma yakapoteredza kukurumidza kutonhora kweAtlantic
Iyo Atlantic Ocean, inoonekwa seimwe yeakanyanya kucherechedzwa uye akatsvagirwa mitumbi yemvura papasi, inobvumira kunyangwe shanduko diki kuti dzionekwe zviri nyore. Nekuda kweizvozvo, kuchinjika kwerekodhi kunotyisa kunomutsa kushushikana munharaunda yesainzi, sezvo shanduko idzi dzinogona kukanganisa zvakanyanya kwete chete mamiriro ekunze epasi rose, asiwo kuwanda uye kuoma kwezviitiko zvemamiriro ekunze zvakaita semadutu. Iyi ndiyo nzira iri kusimukira, yakafanana neye "Atlantic Niña".
Munhau yose, zvakacherekedzwa izvozvo Kudziya kwepasi rose kunokanganisa zvakananga makungwa, zvichiita kuti kuwedzere kwekushisa kwemvura pamusoro pemvura, maitiro akanga atofanotaurwa. Atlantic, zvisinei, iri kupikisa iyi maitiro. Panzvimbo pekuramba ichidziya, nzvimbo dzegungwa dziri kusangana nemamiriro ekunze ekutonhodza, chiitiko chinoramba chisingatsananguriki nemasayendisiti.
Maodzanyemba Atlantic nderimwe rematunhu akanyanya kukanganiswa neiyi kutonhora maitiro, nekudonha kwakanyanya kwekushisa kwakaonekwa mumakore achangopfuura. Kunyangwe dzimwe dzidziso dzichiti shanduko mumafungu egungwa, kutenderera kwemvura kana kunyungudika kweGreenland kungave kuri kukonzera chiitiko ichi, hapana chibvumirano chechokwadi chati chasvika. Zvisinei, dambudziko rinonyanya kunetsa nderekuti, sekutaura kunoita Pedro DiNezio weUniversity yeColorado kuBoulder, shanduko yetembiricha iyi yatangawo kuoneka muEquatorial Atlantic (kunopisa) kubva muna Chivabvu.
Kunyangwe shanduko yeavhareji tembiricha iri pachena, Imwe nzvimbo yakananga yekukura kunetseka itambo yakatetepa padyo neEquator, padyo nemahombekombe eAfrica. Zvinokosha kuziva kuti dunhu iri rakasangana neshanduko inokurumidza kupfuura yakambonyorwa. Kutonhodza kwezhizha kwemvura idzi imhaka yemhepo yekutengeserana inovhuvhuta ichienda kumadokero, iyo inowanzosimbisa panguva ino sezvo bhendi rakatetepa remadutu emumvura richienda kuchamhembe. Kupisa kwegungwa kunobviswa zvishoma kuburikidza nekudyidzana kwemhepo idzi nemvura.
Kukanganisa mamiriro ekunze epasi rose
Mamiriro ekunze epasi rose anokanganiswa zvakanyanya, kunyanya nekuumbwa kwemadutu. Madutu aya anotora simba rawo kubva mukupisa kwegungwa, zvinoreva kuti kusiyana kwematembiricha emvura yepamusoro kunogona kukanganisa maitiro avo zvakanyanya. Atlantic inotonhora inogona kuderedza simba rinowanikwa kune madutu, zvichiita kuti kusava nemhepo ine simba. Zvakadaro, zvimwe zvinhu, zvinosanganisira kushanduka kwemaitiro emhepo uye mwero wemwando, zvakakoshawo mukuvandudzwa kwemamiriro ekunze aya.
Pamusoro pezvo, kudonha kwekushisa kweAtlantic kunogona kuve nemhedzisiro inosvika kure pamamiriro ekunze epasirese. Sechikamu chakakosha chekutenderera kwe thermohaline, Atlantic Ocean inoshanda senge hombe yekuparadzira kupisa kutenderera pasirese. Kana iyo Atlantic ikatonhora, kutenderera uku kunogona kuchinjwa, zvichikanganisa mamiriro ekunze muEurope, North America uye mamwe matunhu akati wandei. Nekuda kweizvozvo, dzimwe nzvimbo dzinogona kutarisana nekupisa kwechando, nepo vamwe vaigona kuona kudziya kana kuoma kwezhizha mamiriro.
Iyo chete fungidziro inogona kuitwa ndeyekuti nepo Pacific La Niña ichiwanzoenderana neyakaoma mamiriro kumadokero kweUnited States uye kuwedzera kunaya kwemvura kumabvazuva kweAfrica, Atlantic La Niña inogona kuderedza kunaya kwemvura mudunhu reSahel yeAfrica uye kuwedzera mune dzimwe nzvimbo dzeBrazil. Nekudaro, pane chikonzero chetarisiro yekuti kuvepo kweAtlantic La Niña kunogona kumisikidza kutanga kwePacific La Niña.
Kukanganisa paBalearic Islands
Kunetseka kukuru kwamuka munharaunda yesainzi maererano nekudonha kunogona kuitika kweGulf Stream, sezvakaburitswa muongororo yakaburitswa mupepanhau reScience Advances. Purofesa wePasi Physics paYunivhesiti yeBalearic Islands (UIB) uye mutungamiriri weInterdisciplinary Laboratory of Climate Change (LINCC), Damià Gomis, akaongorora zvinogona kuitika zvechiitiko ichi kuBalearic Islands. Kuderedzwa kwemafungu eAtlantic kwaizokonzera kutonhora muEurope yose., kunyange zvazvo migumisiro yacho yaizosiyana pakati penharaunda dzekuchamhembe neMediterranean. MuScandinavia, tembiricha yechando inogona kudonha kusvika 30°C (inenge 10°C muzhizha), ukuwo. MuMediterranean paizova nekudonha kwechando kwe3-4ºC uye kudonha kwezhizha kwe1-2ºC.
Zvakakosha kuziva kuti kutonhora kuri kucherechedzwa kunokonzerwa nekudonha kwe AMOC uye kunofanirwa kutariswa pamwe nekudziya kwepasi kunokonzerwa nekukwira kwe CO2 mazinga emuchadenga. KuMediterranean neBalearic Islands, mhedzisiro yepasi rose inogona kusvika zero, zvichienderana neiyo greenhouse gasi emissionory trajectory.
Shanduko dzinocherechedzwa pakunaya kwemvura
Nezve kunaya kwemvura, kudonha kweAMOC kwaizokonzera shanduko huru mumatanho ayo. MuEurope, izvi zvinoreva kuderedzwa kwe10% munguva yechando uye 30% muzhizha. Mukupedzisa, zvitsuwa zveBalearic zvaizotarisana nemhedzisiro, kusanganisira kudonha kwekushisa kwechando uye kuchinja kwemaitiro ekunaya kwemvura. Mhedzisiro yese yekutonhora kunokonzerwa nekutadza kwe AMOC, pamwe nekudziya kwepasirese, zvinoenderana nemamiriro ekuburitswa kwegasi regreenhouse.
Zvidzidzo zvekare zvakange zvanyevera pamusoro pekugona kwekuputsika kweAMOC, kufungidzira kuti inogona kuitika pakati pe2025 ne2095. Zvisinei, chidzidzo chitsva chevatsvakurudzi veUtrecht ndicho chekutanga kuratidza kuvapo kwepoindi yekusadzoka; Kupfuura chikumbaridzo ichi kuchaita kuti kudonha kwehurongwa kusadzivisike.
Mukana wekusvika padanho rakakosha iri pakati pa2025 na2095 unofungidzirwa pa95%, iyo yakakwira zvakanyanya kudarika kufanotaura kwakaitwa mumishumo yeIPCC. Uyezve, chidzidzo chacho chinoratidza kuti kuputsika kunogona kuitika kare kupfuura zvaitarisirwa, zvichiita kuti zvishoma nezvishoma mamiriro ekunze aonekwe mukuderera kwekushisa kuchamhembe kweEurope.
