Yin farin ciki

Canjin yanayi yana jefa shakku sosai akan binciken kimiyya game da glaciations. Kuma abin shine a shekara ta 2004 muna da wani sanyin hunturu, tare da ɗan ruwan sama da kuma gobarar daji da ta bazu ko'ina cikin duniya. Waɗannan hujjojin sun haifar da mahawara tsakanin kimiyya game da hawan yanayi da haɗarin da ke tattare da wannan canjin yanayi. Akwai wadanda ke nuna goyon baya ga cewa dumamar yanayi ba wani abu bane da dan adam ke haddasawa ba, sai dai kuma hakan ya dace da daya daga cikin abubuwanda ake samu na kankarar da ake samu daga wannan lokaci zuwa lokaci.

A cikin wannan labarin zamu gaya muku duk abin da kuke buƙatar sani game da ƙyalƙyali da alaƙar su da canjin yanayi.

Oscillations a yanayin zafi

An san cewa a cikin karnin da ya gabata yanayin duniya ya sami ƙaruwa a matsakaicin yanayin zafinsa. Wannan saboda karuwar ne tarin carbon dioxide da sauran iskar gas tare da damar riƙe zafi a cikin yanayi. Matsalar ita ce cewa akwai mutanen da suke cewa duniyarmu tana da zagayowar yanayin ƙyalƙyali. Gaskiya ne cewa a duk lokacin juyin halittar wannan duniyar tamu akwai lokutan zagayawa na glaciations da lokutan tsakanin-glacial. Koyaya, matsalar tana farawa lokacin da muka sanya a matsayin mai canza canjin saurin waɗannan ƙanƙanin da kuma dumamar yanayin da ke gabansu.

Kamar yadda ake iya gani a cikin tarihin kirinjin, wanda zamu gani nan gaba, lokacin da ya wuce tsakanin wankan kan da wani ya isa sosai ga dukkan nau'ikan dabbobi da tsirrai da tsarin halittar halittu don daidaitawa da canje-canje a yanayin. A wannan yanayin, muna magana ne akan karuwa a yanayin matsakaicin yanayin duniya cikin kankanin lokaci. Irin wannan gajeren lokaci da jinsunan basu da lokacin daidaitawa kuma sun fara rage yawan mutanen su. Wannan shi ne raguwar yawan jama'a wanda yawancinsu suka mutu.

Don kawar da dukkan shakku, zamu sanya wasu tabbaci game da abubuwan da suka gabata da kuma binciken kimiyya da aka gano. Wadannan binciken sun tattaro dukkanin hanyoyin da suke da nasaba da canjin yanayin duniya. Dole ne a yi la'akari da cewa, ba tare da tasirin tasirin aikin ɗan adam ba, masana kimiyya sun yarda da cewa sune ainihin abubuwan da ke haifar da canjin yanayi babban yanayin kankara tare da murƙushewar yanayin juyawar Duniya. Canje-canje a cikin kewayar duniya da ke kewaye da rana an kuma ƙara ta da wannan. Wannan ya faru ne saboda dukkan wasu motsi suna canza yadda ake rarraba makamashin da duniyarmu take samu daga rana.

Shekarun kankara da canje-canje a cikin zagayen duniya

Don sanin lokutan kankara da masu ƙanƙarar duwatsu, ya zama dole a kimanta matsakaita yanayin shekara-shekara daga yanayin ilimin ƙasa. Ka'idar Milankovitch ita ce wacce ta ba da hujjar cewa akwai canje-canje a yanayin duniya bayan bayyanar lokaci-lokaci na Glaciations. Anan ne manyan shekarun kankara da ƙananan lokutan rikice rikice suka bayyana. A yanzu muna cikin wani zamani ne na rikice-rikice.

Wadannan lokutan glaciations suna faruwa ne saboda hadewar zagaye na sararin samaniya guda 3 wanda zagayewar Duniya ke canzawa daga madauwari zuwa elliptical kuma akasin haka. Akwai rikodin cewa ɗayan farkon zagaye na sararin samaniya ya faru tsakanin shekaru 90.000 zuwa 100.000 da suka wuce. Hakan ne lokacin da duniya ta canza zagayenta daga madauwari zuwa mai juyawa kuma akasin haka. Wani sake zagayowar sararin samaniya ya faru kimanin shekaru 26.000 kuma yana ƙayyade rawanin juyawar duniya. A ƙarshe, wani zagayen sararin samaniya na shekaru 41.000 ya faru wanda ya karkata ga yanayin duniya game da jirgin saman da ke zagayawa tsakanin digiri 22.5 da 24.5.

Hanyoyin motsa jiki

Duk waɗannan canje-canjen a cikin motsi da rawanin duniya sune manyan kera glaciations. Dole ne a la'akari da cewa matakan da kewayen duniya yana zagaye ne da zaran canje-canje sun faru a duk shekara. Koyaya, lokacin da kewayar ke motsawa, akwai kusanci mafi girma a wasu lokuta na shekara. A halin yanzu, mun san cewa kewayar duniya dangane da rana tsinkaye ne, kodayake ba ta kai matuka ba sai ta eccentricity. Lokacin da duniya ke wucewa ta hanyar haɗari, wannan shine maɓallin kewayawa kusa da rana, yana faruwa a farkon watan Janairu. Wannan lokacin ne lokacin sanyi a yankin arewacin duniya. A gefe guda kuma, lokacin da yake cikin aphelion, lokacin rani ne a arewacin duniya, duk da cewa yana cikin mafi nisan wurin.

Yaushe ne abubuwan da ke sararin samaniya zasu danganta wannan canje-canjen, tsawon lokaci a cikin hadari hakan yana faruwa daidai da lokacin hunturu na kudu a maimakon wanda yake birgeshi. Sabili da haka, sananne ne cewa maɓallin tasirin waɗannan canje-canje na ɗabi'a a kan bayyanar glaciations ya yarda da samfurin Milankovitch. Kuma shi ne cewa komai yana da alaƙa da lokacin da kewayar yake kewaya kuma nesa da ƙasa da wuya ya sha bamban. A wannan halin, bazarar bazara kamar ta yanzu ba ta faruwa. A gefe guda, a cikin matakan da kewayar ke juyawa kuma tana da iyakar eccentricity, lokacin rani mai zafi kamar na yanzu yana faruwa.

Lokacin da kewayar ta fi zagaye Yana hana dusar kankara narkewa kuma a hankali tana taruwa kowace shekara. Wannan ya saita duniya zuwa sabuwar zamanin kankara. An zana wannan azaman ƙarshe cewa abin da ke ƙayyade glaciations ba shine mafi tsananin damuna ba, amma lokacin bazara mafi kyau. Daga nan ne aka ciro bayanin cewa saboda lokacin bazara, yanayin dusar kankara ba zai fito ba kuma a kowace shekara kankarar kankara na kara kauri har zuwa karshen zamanin kankara.

Sanannun shekarun kankara a Duniya

Waɗannan sune glaciations daban-daban waɗanda suka san duniyarmu cikin tarihi:

• Na farko glaciation da aka sani da Huronian. Ya faru kusan shekaru biliyan 2.400 da suka wuce. Ya ɗauki kimanin shekaru miliyan 300 kuma shi ne mafi tsayi duka.
• Na biyu glaciation da aka sani da Cryogenic. Zai yuwu shine mafi tsananin kuma ya faru kusan shekaru miliyan 850 da suka gabata. Ita ke da alhakin fashewar Cambrian mai zuwa.
• Na uku glaciation da aka sani da Andean-Saharan. Ya faru kusan shekaru miliyan 460 da suka gabata.
• An sanya glaciation na huɗu bayan karo kuma ya faru ne kimanin shekaru miliyan 350 da suka gabata.
• A cikin glaciation na yanzu, da ake kira Wutar gilashin Quaternary, Ya ga lokutan kankara kusan shekaru 40.000.

Ina fatan cewa tare da wannan bayanin zaku iya ƙarin koyo game da ƙyamar glaciations.