Iyo iceberg yakakura kwazvo pasi rose, inozivikanwa seA23a, yave zvakare protagonist mushure memakumi emakore akabatikana pazasi pegungwa reSouthern Ocean.. Iri guru guru rechando, iro rine nzvimbo inosvika Makiromita 3.600 makiromita uye huremu hunofungidzirwa hunenge matani bhiriyoni, yatanga kukukurwa, ichitanga rwendo rwunogona kuratidza kutsakatika kwayo chaiko. Kubva payakatanga kubereka muna 1986, iceberg iyi yakatariswa nekudzidzwa nenharaunda yesainzi yepasirese, iyo kufarira kwayo kwakanangana nekunzwisisa maitiro ayo uye maitiro ayo pazvipenyu zvegungwa.
Kweanopfuura makumi matatu emakore, A23a yakaramba yakabatikana muGungwa reWeddell, yakavharirwa neinozivikanwa se "Taylor's Column," mhepo yepasi pemvura yairamba ichitenderera panzvimbo.. Zvisinei, mumakore achangopfuura, ice colossus iyi yakakwanisa kuzvisunungura uye yakatanga kukweverwa kuchamhembe nemafungu egungwa. Masayendisiti kubva kuBritish Antarctic Survey (BAS) akasimbisa mafambiro ayo kuburikidza nemifananidzo yesatellite, zvichiratidza kutanga kwedanho idzva munhoroondo yayo refu yejoloji.
Sei yabva zvino?
Iyo detachment yeA23a inokonzerwa nekubatanidzwa kwezvinhu zvakasikwa uye pamwe nekukanganisa kwekushanduka kwemamiriro ekunze. Kubva zvakapatsanurwa kubva kuFilchner Ice Shelf muAntarctica muna 1986, iceberg iyi yakaramba yakagadzikana nekuda kwehukuru hwayo uye kusangana kwayo nepasi pegungwa. Nekudaro, kusiyana kwemamiriro ekunze emugungwa nemamiriro ekunze, pamwe chete nemamiriro ekunze ekunze kwemapendero ayo, zvakatora basa rakakosha mukuburitswa kwayo.
Kudziya kwepasi rose kungadai kwakakurumidza kuita izvi, sezvo kuwedzera kwekushisa munharaunda yeAntarctic kunokanganisa zvose zviri zviviri mhepo nemvura, kunoderedza chimiro chechando. Nekudaro, mamwe masayendisiti anoratidza kuti nzira yeA23a inogona kunge iri chikamu chekutenderera kwechisikigo chechando chechando, icho chinoda kubvaruka, kuenda kumvura inodziya, kutsemuka uye pakupedzisira kunyangarika.
Nzira yekuparara kwayo
A23a iri kutevera nzira inozivikanwa se "iceberg alley," inofambiswa neAntarctic Circumpolar Current.. Rwendo urwu ruchakutora wakananga kuSouth Atlantic uye pamwe huchakuunza padyo neiyo subantarctic Island yeSouth Georgia. Ikoko, iceberg ichatarisana nemvura inodziya, iyo ichakurumidzisa kuparara kwayo kuita zvidimbu zviduku zvinozopedzisira zvanyunguduka zvachose.
Kufamba uku hakuna kujairika kune icebergs calving kubva kuAntarctica, asi chinoita kuti A23a ive yakakosha kukura kwayo uye zera, zvichiita kuti ive yakasarudzika nyaya yekudzidza kune vanoongorora. Kunyangwe kwainoperera kune chokwadi, masayendisiti anoenderera mberi nekutarisa mafambiro ayo uye mamiriro ekuwana data yakakosha nezvemaitiro echisikigo ane chekuita nehupenyu hwema icebergs.
Impact pane marine ecosystem
Giant icebergs seA23a inoita basa rakakosha mumakungwa ecosystems. Sezvavanoparara, vanosunungura zvakakosha zvinovaka muviri mumvura yakapoteredza, ichikurudzira kukura kwezvisikwa zviduku zvakadai se phytoplankton, iyo inozoshanda sehwaro hwemaketani makuru ezvokudya. Laura Taylor, purojekiti biogeochemist BIOPOLE, yakatsanangura kuti izvi zvinovaka muviri zvinogona kushandura nzvimbo dzisina zvibereko zvishoma kuti dzive nzvimbo dzechokwadi dzezvipenyu zvegungwa.
Pamusoro pezvo, A23a iri kudzidzwa kuti inzwisise kuti icebergs inokanganisa sei global carbon cycles uye zvinovaka muviri. Masayendisiti anga achiunganidza masampuri emvura akatenderedza iceberg kuti aongorore maitiro ayo pane kabhoni chiyero pakati pegungwa nemhepo, iyo yakakosha nyaya yekugadzirisa shanduko yemamiriro ekunze.
Dambudziko rekushanduka kwemamiriro ekunze
Mamiriro eA23a anoratidzawo mhedzisiro yekushanduka kwemamiriro ekunze munzvimbo yepolar. Maererano nemishumo yazvino kubva ku World Meteorological Sangano, inopfuura 90% yemakungwa epasi rose yakasangana nemafungu ekupisa mumakore achangopfuura, zvichikonzera kuchinja kukuru muAntarctica. Mamiriro ezvinhu aya ari kuderedza kuwanda kweaizi yegungwa uye kukurumidza kunyungudika kwemazaya echando.
Nekudaro, kuchine zvakawanda zvisingazivikanwe nezve shanduko yemamiriro ekunze inobata sei hofori yechando seA23a. Zvidzidzo zvakaita sezvakaitwa ne British Antarctic Survey Izvo zvakakosha kuti unzwisise maitiro aya uye kugadzira mazano ekudzikamisa maitiro avo pane ese epasirese mamiriro ekunze uye ecosystems.
Kufamba kweA23a kunomiririra hukuru uye fragility yezvisikwa. Rwendo rwavo kuchamhembe harungoratidzi kupera kweaizi hofori, asi zvakare rinovhura hwindo kuti riongorore maitiro echisikigo uye emamiriro ekunze anopindirana mumakungwa epolar. Mwedzi iri kuuya ichave yakakosha kuti tinzwisise zviri nani kukanganisa kwechiitiko ichi pane ecosystem yegungwa uye kuti ndezvipi zvidzidzo zvatingatora kutarisana nematambudziko ekushanduka kwemamiriro ekunze.