Ragewar Arctic

Raguwar yawan kankara na teku na arctic (yanki) tun 1979Rage yawan kankara na teku tun 1979Gishiri na teku a yankin Arctic ya ragu a cikin 'yan shekarun nan a cikin yanki da girma saboda Canjin yanayi. Ya kasance yana narkewa sosai a lokacin rani fiye da yadda yake sanyaya a cikin hunturu. Rashin dumama na duniya, wanda ya haifar da tilasta iskar gas ne ke da alhakin raguwar kankara na teku na Arctic. Raguwar kankara na teku a cikin Arctic yana hanzarta a farkon karni na ashirin da daya, tare da raguwar kashi 4.7% a kowace shekara goma (ya ragu sama da 50% tun lokacin da aka fara yin rikodin tauraron dan adam). Wataƙila kankara ta teku ta lokacin rani za ta daina wanzuwa wani lokaci a cikin karni na 21.

Yankin ya kasance mafi zafi a cikin akalla shekaru 4,000.  Bugu da ƙari kuma, lokacin narkewar Arctic-fadi ya tsawaita a cikin adadin kwanaki biyar a cikin shekaru goma (daga 1979 zuwa 2013), wanda ya mamaye daskarewar kaka daga baya.  Rahoton kimantawa na shida na IPCC (2021) ya bayyana cewa yankin kankara na Arctic zai yi yuwuwa ya faɗi ƙasa da kilomita miliyan 2 a cikin aƙalla wasu Satumba kafin 2050.  A cikin Satumba 2020, Cibiyar Bayanan Kankara da Kankara  ta ba da rahoton cewa ƙanƙarar tekun Arctic a cikin 2020 ta narke har zuwa nisan kilomita miliyan 3.74 2, mafi ƙanƙanta  tun lokacin da aka fara rikodin a 1979. ton na wannan asarar. Adadin asarar kankara ya karu da kashi 57% tun daga shekarun 1990. 

Rashin kankara na teku yana daya daga cikin manyan direbobi na fadada Arctic, abin da ya faru cewa Arctic yana da sauri fiye da sauran duniya a ƙarƙashin canjin yanayi. Yana da kyau cewa raguwar kankara na teku ya sa jet ya raunana, wanda zai haifar da ci gaba da matsanancin yanayi a tsakiyar latitudes. Jirgin ruwa yana yiwuwa sau da yawa a cikin Arctic yanzu, kuma mai yiwuwa zai kara ƙaruwa. Dukkanin ɓacewar kankara na teku da kuma yiwuwar ƙarin ayyukan ɗan adam a cikin Tekun Arctic suna haifar da haɗari ga namun daji na gida kamar bears.

Ɗaya daga cikin muhimman al'amura wajen fahimtar raguwar kankara na teku shine anomaly na Arctic dipole . Wannan sabon abu ya bayyana ya rage yawan asarar kankara tsakanin 2007 da 2021, amma irin wannan yanayin tabbas ba zai ci gaba ba.

## Ma'anar
 
Tekun Arctic shine yawan ruwa da ke sama da latitude 65 ° N. Tekun Arctic Ice yana nufin yankin Tekun Arctic da kankara ya rufe. *Ƙananan kankara na teku na Arctic* shine rana a cikin shekara da aka ba lokacin da kankara na Arctic ya kai mafi ƙanƙanta, yana faruwa a ƙarshen lokacin narkewar bazara, yawanci a watan Satumba. *Matsakaicin kankara na Tekun Arctic* shine ranar shekara lokacin da kankara ta Tekun Arctic ta kai mafi girma kusa da ƙarshen lokacin sanyi na Arctic, yawanci a lokacin Maris. Bayanan da aka saba gani don kankara na teku na Arctic sun haɗa da matsakaicin ma'auni na kowane wata ko zane-zane don mafi ƙarancin shekara-shekara ko matsakaicin lokaci, kamar yadda aka nuna a cikin hotunan da ke kusa.

An bayyana *girmansa* kankara na teku a matsayin yankin da ke da akalla 15% na rufe kankara na ruwa; ana amfani dashi sau da yawa azaman ma'auni fiye da yanki mai sauƙi na kankara. Ana amfani da wannan ma'auni don magance rashin tabbas wajen rarrabe ruwan teku mai budewa daga ruwan da ya narke a saman kankara mai ƙarfi, wanda hanyoyin gano tauraron dan adam ke da wahalar rarrabewa. Wannan batu ne da farko a cikin watanni na rani.

#### Bayanan da suka gabata
Halin da aka nuna a cikin rikodin microwave daga 1978 zuwa tsakiyar 1995 ya nuna cewa girman kankara na Arctic yana raguwa 2.7% a kowace shekara goma. Ayyukan da suka biyo baya tare da bayanan tauraron dan adam na microwave sun nuna cewa daga ƙarshen Oktoba 1978 zuwa ƙarshen 1996 girman kankara na teku na Arctic ya ragu da kashi 2.9% a kowace shekara goma. Yankin kankara na teku na Arewacin Hemisphere ya nuna raguwar 3.8% ± 0.3% a kowace shekara goma daga Nuwamba 1978 zuwa Disamba 2012.

## Rashin kankara na gaba
 Kimanin ainihin shekarar da Tekun Arctic zai zama "ba tare da kankara ba" yana da matukar wahala, saboda babban rawar da ke tattare da bambancin shekara-shekara a cikin yanayin kankara na teku. A cikin Overland da Wang (2013), marubutan sun bincika hanyoyi daban-daban guda uku na hango hasashen matakan kankara na teku na gaba. Sun lura cewa matsakaicin dukkan samfuran da aka yi amfani da su a cikin 2013 sun kasance shekaru da yawa bayan abubuwan lura, kuma kawai ƙananan samfuran da suka fi asarar kankara sun iya daidaita abubuwan lura. Koyaya, marubutan sun yi gargadin cewa babu tabbacin cewa waɗannan samfuran za su ci gaba da daidaita abubuwan lura, sabili da haka kimantawar su game da yanayin da ba shi da kankara da ya fara bayyana a cikin 2040s na iya kasancewa da kuskure. Don haka, sun ba da shawarar yin amfani da hukunci na ƙwararru ban da samfuran don taimakawa wajen hango hasashen abubuwan da suka faru a Arctic ba tare da kankara ba, amma sun lura cewa ana iya yin hukunci na ƙwararrun ta hanyoyi biyu daban-daban: kai tsaye yana nuna yanayin asarar kankara (wanda zai ba da shawarar yanayin raguwa mai saurin raguwa wanda aka nuna ta lokutan "babban narkewa" na lokaci-lokaci (kamar na 2007 da 2012) wanda ke tura kwanan wata zuwa 2028 ko ci gaba zuwa cikin 2030s, dangane da farkon zato game da girman lokacin narkewa. Sakamakon haka, akwai tarihin kwanan nan na tsinkaye masu gasa daga samfuran yanayi da kuma masana.

## Manazarta