Muna komawa cikin lokaci don neman wani bala'i na duniya. A ƙasa, Na sake gabatar da tebur tare da sake zagayowar sake saiti. Bisa ga tebur, bambancin hawan keke a cikin 2186 BC shine 95.1%, yana nuna yiwuwar sake saiti mai rauni. A zahiri, sake saitin a waccan shekarar yana da ƙarfi sosai, wanda ke nufin cewa ainihin sake saiti na sake saiti a wancan lokacin ya ɗan bambanta da bayanan da ke cikin tebur. Zagayen shekaru 676 ya nuna cewa sake saiti na gaba zai faru a cikin 2446 BC. Duk da haka, saboda an canza zagayowar, rashin daidaituwa a cikin shekara ta 2446 BC bai kasance da gaske 3.5% kamar yadda aka nuna a cikin tebur ba, amma dole ne ya kasance mafi girma. Don haka bai kamata a sake saiti ba sannan kuma babu wani bayani game da bala'i a wannan shekarar. Ci gaba, mun zo shekara ta 2862 BC. A nan ma babu wani bala'i a duniya, ko da yake ana iya samun wasu bayanai cewa an yi girgizar kasa mai tsanani a wasu wurare a cikin wannan shekarar. Babban bala'i na gaba dole ne mu bincika kawai a cikin ƙarni na farko.

Gabatar da tarihi zuwa canjin tarihi

Ƙarshen karni na huɗu BC shine juyi ga ɗan adam, lokacin da zamanin prehistory ya ƙare kuma ya fara tsufa. Har ila yau, lokaci ne da abubuwan da ke faruwa a yanayin yanayi na duniya. Don haka, ina ganin yana da kyau a yi nazari sosai kan abin da ya faru a wannan lokacin. Ka tuna, duk da haka, ƙananan shaidar tarihi daga wannan lokacin sun tsira. Bari mu dubi shekara ta 3122 BC da aka bayar a cikin tebur. Bambance-bambancen kewayon anan yakamata ya zama 5.2%. Wannan abu ne mai yawa, amma idan sake zagayowar ya ɗan motsa, ƙila sake saiti ya faru a nan. A wannan yanayin, zai kuma fara farawa da wuri fiye da yadda tebur ya nuna. Lokacin bala'i zai kasance a nan a cikin shekaru 3122-3120 BC.

Bala'in duniya

Nazarin kankara na kankara ya nuna cewa a kusa da 3250-3150 BC an sami karuwa kwatsam a cikin ma'aunin sulfur a cikin iska, tare da raguwa mai yawa a cikin ƙwayar methane.^{(ref., ref.)} Kuma kalandar dendrochronological yana nuna girgizar yanayi wanda ya fara a 3197 BC. Zoben bishiyar sun rubuta tsawon shekaru 7 na yanayin yanayi mai tsanani wanda bala'in da ba a san shi ba ya haifar. Ya kasance mafi munin rashin lafiya a cikin duka karni na huɗu BC. Na yi imani cewa wannan shekara ya kamata a canza shi zuwa shekaru 64, kamar yadda na canza wasu kwanakin daga wannan kalandar dendrochronological. Don haka ya bayyana cewa wani babban bala'i ya faru a shekara ta 3133 BC. Wannan yana kusa da shekara ta 3122 BC, wanda aka ba da shi a cikin tebur a matsayin shekarar yiwuwar bala'i a duniya. Yana yiwuwa alamun dendrochronologists ba daidai ba ne ta waɗannan shekaru 11. Bayan haka, mun san cewa a cikin lokutan yanayi na anomalies, bishiyoyi na iya yin ganye da 'ya'yan itace sau biyu a shekara. Gregory na Tours ya rubuta cewa haka lamarin yake a lokacin annoba ta Justinian. A karkashin irin wannan yanayi, bishiyoyi kuma suna samar da zobba biyu a kowace shekara, kuma wannan na iya haifar da kuskure a cikin dangantaka na dendrochronological. Akwai hasashe da yawa game da abin da zai iya haifar da wannan girgizar yanayi. Watakila fashewar aman wuta ne, ko da yake ba a san fashewar da ta yi daidai da girma da lokaci ba. Yawancin masu bincike na cataclysms suna ɗokin neman tasirin babban asteroid da ke buga Duniya a lokacin.

Canjin yanayi ba zato ba tsammani

A lokacin an yi sanyi da fari kwatsam a duniya. A cikin ilmin halitta, ana kiran wannan lokacin da Piora Oscillation. An sanya wa al'amarin sunan kwarin Piora da ke Switzerland, inda aka fara gano shi. Wasu daga cikin mafi ban mamaki shaida ga Piora Oscillation zo daga yankin na Alps, inda sanyaya ya haifar da ci gaban da glaciers. Tsawon lokacin Oscillation na Piora an bayyana shi daban-daban. Wani lokaci a kunkuntar, zuwa shekaru kusan 3200-2900 BC.^(ref.) kuma wani lokacin fiye da haka, daga kimanin shekaru 5.5 dubu BP (3550 BC) ko kuma daga kimanin shekaru 5.9 dubu BP (3950 BC). A haƙiƙa, dukan karni na huɗu BC an kwatanta shi da lokuta masu maimaita sanyi da fari. Yana yiwuwa kowane ɗayan waɗannan shekarun yana da alaƙa da sake saiti, domin kuma a cikin 3537 da 3953 BC rashin daidaituwa na zagayowar ya yi ƙanana kuma yana yiwuwa a sami sake saiti a lokacin. A nan zan mayar da hankali ne kawai kan abubuwan da suka shafi sauyin yanayi kwatsam kimanin shekaru 5.2 da suka wuce.

An gano taron BP na tsawon kilo 5.2 a duk duniya a matsayin lokacin da ake samun canjin yanayi ba zato ba tsammani. A cewar masana kimiyyar burbushin halittu, ya faru ne ta hanyar dogon lokaci tabbatacce na Oscillation na Arewacin Atlantika.^(ref.) Yanayin a wancan lokacin ya yi kama da na abin da ya faru a tsawon shekaru 4.2. An yi ruwan sama akai-akai da yawa a Arewacin Turai. Binciken da aka yi daga yammacin Ireland ya nuna shaidar wani matsanancin yanayi na yanayi, mai yiwuwa jerin guguwa, a kusa da 3250-3150 BC.^(ref.) Wannan ya zo daidai da jerin sakamako daga Switzerland zuwa Ingila zuwa Greenland, wanda ke nuna canje-canje a tsarin mulkin Atlantic. Haka kuma, an yi fari a kudu. A Afirka, fari da ake ta fama da shi ya haifar da samuwar hamadar sahara a yankunan da a da ke da danshi da cunkoson rayuwa. Kuna iya ƙarin koyo game da koren Sahara a cikin wannan bidiyon: link.

Yankin sahara na yau ya taba lullube da savannah da manyan tafkuna da koguna masu yawa. Dabbobi da yawa sun zauna a can: raƙuman ruwa, zakuna, hippos, amma har da mutane, wanda aka tabbatar da zane-zanen dutsen da aka samu a wurare da yawa a cikin hamada. Mutanen da a da suke zaune a wannan yanki sun bar su a baya. Har zuwa ’yan shekaru dubu da suka shige, Sahara wuri ne da ya dace da zama. Koyaya, raƙuman fari na tsayin daka na ci gaba da faruwa a cikin ƙarni na huɗu BC ya haifar da samuwar hamada. Yankunan Arewacin Afirka sun daina zama. An tilasta wa mutane neman sabon wuri, wani wuri kusa da ruwa. Suka fara ƙaura suka zauna kusa da manyan koguna.

Babban ƙaura da haɓakar ƙasashen farko

Sakamakon kwararowar hamada a hankali a hamadar Sahara, musamman a lokacin bikin na tsawon kilo 5.2, mutane sun fara yin watsi da salon rayuwar makiyaya gaba daya tare da ƙaura zuwa yankuna masu albarka kamar kwarin Nilu da Mesopotamiya. Ƙaruwar yawan jama'a a waɗannan wurare ya haifar da fitowar ƙungiyoyin birane na farko, masu matsayi. Wayewar farko ta fara bayyana a Masar, arewa ta tsakiyar kasar Sin, a gabar tekun Peru, a cikin kwarin Indus, da Mesopotamiya, da kuma a yammacin Asiya.^(ref.)

Tarihin d ¯ a Misira ya fara ne da haɗin kai na Sama da Ƙarƙashin Masar a kusa da 3150 BC.^(ref.) Tsawon ƙarnuka, Sama da Ƙasa Masar sun kasance ƙungiyoyin zamantakewa da siyasa daban-daban. Rikodin tarihin haɗin kai yana da duhu kuma yana cike da rashin daidaituwa, rabin gaskiya, da almara. Wataƙila Sarki Mena ya haɗa yankunan biyu, mai yiwuwa ta hanyar ƙarfin soja.

A Mesopotamiya, a kusan 3150-3100 BC, al'adun Uruk na tarihi ya rushe.^(ref.) Wasu masu sharhi sun danganta ƙarshen lokacin Uruk tare da sauyin yanayi da ke da alaƙa da Oscillation na Piora. Wani bayanin da aka bayar shine zuwan kabilun Semitic na Gabas wanda wayewar Kish ke wakilta.^(ref.) Don haka, kamar yadda ya kasance tare da sauran sake saiti, sauyin yanayi da ƙaura suna ba da gudummawa ga raguwar al'adu. Ya zuwa karni na 3 BC, cibiyoyin birane a Mesopotamiya sun haɓaka zuwa al'ummomi masu rikitarwa. Ban ruwa da sauran hanyoyin amfani da abinci sun samar da damammaki na tara rarar abinci. Ƙungiyoyin siyasa sun ƙara haɓaka, kuma masu mulki sun fara gudanar da manyan ayyukan gine-gine.^(ref.)

Kusan 3100 BC, an ƙirƙira rubutu a Mesopotamiya da Masar. Wannan taron yana nuna iyaka tsakanin tarihi kafin tarihi da kuma tsoho.^{(ref., ref.)} Na yi imanin cewa an ƙirƙira rubutun ne a lokacin, domin a lokacin ne mutane suka fara buƙatarsa. Yayin da suke rayuwa a cikin manyan al'ummomi, suna buƙatar rubuta bayanai daban-daban, misali na wane ne.

An kuma gina manyan gine-ginen tarihi na farko a wannan lokacin. Newgrange - babban kabari na corridor a Ireland, ya koma ca 3200 BC.^(ref.) Lokaci na farko na Stonehenge yana kwanan wata zuwa 3100 BC.^(ref.) Wannan ya nuna cewa kuma a cikin Tsibirin Biritaniya, wayewar da aka tsara ta fito a lokaci guda.

Shekarar halittar duniya

Mai yiyuwa ne cewa duk waɗannan manyan sauye-sauyen zamantakewa sun kasance sakamakon bala'in duniya da sauyin yanayi na gaba. Abin takaici, bayanai daga wannan lokacin ba su da inganci, don haka ba shi da sauƙi a tantance ainihin shekarar waɗannan abubuwan. Shekara mafi aminci ita ce 3133 BC, wanda masana dendrochronologists suka bayar.

Tatsuniyar Mayan na iya taimakawa wajen tantance shekarar bala'in. Mayakan sun yi imani cewa kafin duniya ta yanzu akwai uku a baya. Duniya ta farko tana da halittun dwarf waɗanda suke kama da dabbobi kuma ba sa iya magana. A duniya ta biyu, an yi mutane da laka, kuma a duniya ta uku, an yi mutane da itace. Kamar yadda yake a cikin tatsuniyar Aztec, a nan ma duk duniyoyin sun ƙare cikin bala'i. Daga baya an halicci duniya ta yanzu. A cewar Popol Vuh, wani littafi mai tsarki na Maya, uba na farko da uwa ta farko sun halicci duniya kuma suka halicci mutane na farko daga kullun masara da ruwa.

Kalandar Mayan Long Count tana farawa ne da shekarar halittar duniya, wadda Mayakan suka yi imani da ita ita ce 3114 BC. Abin sha'awa, wannan ƴan shekaru kaɗan ne kawai daga yiwuwar sake saiti a 3122-3120 BC! Wani lamari ne mai ban sha'awa sosai cewa zamanin Mayan ya fara a daidai lokacin da aka kafa kasashe na farko a Gabas ta Tsakiya, kodayake sun ci gaba da kansu.

Mayakan kuma sun rubuta tarihin wasu abubuwan da suka faru kafin zamanin nan. Ɗaya daga cikin rubutun da aka gano a cikin haikali a Palenque ya ba da ranar 12.19.11.13.0 (3122 BC) da aka sanya hannu a matsayin: "Haihuwar Uban Farko".^{(ref., ref.)} Kusa da shi akwai kwanan wata: 12.19.13.4.0 (3121 BC) - "Haihuwar Uwar Farko". Idan muka ɗauka cewa an haifi waɗanda suka halicci duniya ta yanzu bayan halakar duniyar da ta gabata, to, bala'in duniya zai faru a cikin 3122-3121 BC, kuma wannan zai kasance gaba ɗaya daidai da zagayowar sake saiti!

Ko da yake bayanin daga farkon tarihi ba shi da kyau kuma ba daidai ba ne, na sami shaidu da yawa na sake saiti a kusa da 3121 BC. Ba a san ainihin abin da ya faru a nan ba, amma tabbas akwai duk bala'o'in da muka sani daga sake saitin da aka bayyana a baya. Masu bincike na Cataclysm suna neman babban tasirin asteroid a nan, wanda ina tsammanin yana iya yiwuwa. Tabbas an sake samun sauyin yanayi kwatsam, sakamakon sauyin yanayi na zagayawa na tekuna da yanayi. Sakamakon fari, wurare masu albarka da mutane suka yi rayuwa cikin lumana da wadata sun bace. Lokacin ƙaura mai girma yana nan kuma. Mutane sun fara taruwa a kusa da koguna, inda suka kafa kasashe na farko. Da alama a cikin wannan yanayin bala'in ya ba da gudummawa ga ci gaban wayewa. Zamanin prehistory ya ƙare kuma an fara tsufa.

Ruwan Bahar Maliya

Sources: An rubuta bisa tushen nazarin ilimin ƙasa - An abrupt drowning of the Black Sea shelf af 7.5 Kyr B.P, WBF Ryan et al. (1997) download pdf), da kuma labarin kan wannan batu a cikin New York Times, da sauran kafofin.

Dubban shekaru da suka gabata, akwai wani tabki na ruwa a yankin tekun Black Sea a yau. An raba shi da Tekun Bahar Rum ta wata ƴar ƴar ƴan iska, kuma ruwan tafkin ya kai kimanin mita 150 ƙasa da matakin teku. Duk da haka, kimanin shekaru 7,500 da suka shige, ruwan teku ba zato ba tsammani ya faɗo cikin mashigin. Ruwa mai yawa ya mamaye wurare masu yawa, ya zama Bahar Maliya.

A shekara ta 1997, wata ƙungiyar ƙasa da ƙasa ta masana kimiyyar ƙasa da masu nazarin teku sun ba da shawarar wani bala'i na kwararar ruwan tekun Bahar Rum zuwa cikin tafkin ruwan Baƙar fata. Wannan shi ne yanayin da aka fi amincewa da samuwar Tekun Bahar Rum. William Ryan da Walter Pitman na Jami'ar Columbia da abokan aikinsu sun sake gina tarihin wannan bala'in ambaliya daga bayanan da wani jirgin ruwa na Rasha ya tattara. Sautunan girgizar ƙasa da ɓangarorin ɗigon ruwa sun bayyana alamun tsoffin layukan tafkin. Rijiyoyin burtsatse a cikin Tekun Kerch sun gano tsakuwa mai tsakuwa tare da namun daji a zurfin mita 62 a cikin gadon tsohon kogin Don, sama da kilomita 200 daga bakin kogin na yanzu. Radiocarbon Dating na sediments ya ƙaddara canji daga ruwa mai tsabta zuwa kwayoyin ruwa a kusa da 7500 BP (5551 BC).

A lokacin glaciation na ƙarshe, Bahar Maliya babban tafkin ruwa ne. An raba shi da Tekun Bahar Rum ta wani ɗan ƙaramin tsibiri a kan mashigin Bosporus na yau. Ƙasar Bahar Rum da Tekun Marmara sun tashi a hankali zuwa matakin da ya kai mita 150 (ƙafa 500) sama da matakin tafkin. Sa'an nan ruwan teku ba zato ba tsammani ya zuba a cikin Bosphorus. A cewar masu binciken, 50 zuwa 100  km³ (12 – 24 mi³) na ruwa suna ta kaɗawa kowace rana tare da ƙarfi sau 200 fiye da na Niagara Falls. Zurfafa tsaunuka a cikin Bosporus a yau suna da alama suna ba da shaida ga ƙarfin ruri mai ruri wanda ya canza Bahar Maliya har abada. Gudun ruwan zai iya kaiwa sama da 80 km/h (mph 50). Ana iya jin ƙarar ƙaƙƙarfan ƙaƙƙarfan ruwan gudu daga nesa na akalla kilomita 100 (mita 60). Dokta Pittman ya kammala da cewa lallai saman tafkin ya kasance yana tashi ne a tsawon 30 zuwa 60 cm a kowace rana. Ruwan da ba ya ɗorewa yana mamaye ƙasar a cikin adadin rabin mil zuwa mil a kowace rana. A cikin kasa da shekara guda, Tekun Bahar Maliya ya rikide daga tafki mai cike da ruwa zuwa tekun da ke hade da tekunan duniya, inda ya mamaye tsoffin tudu da kwarin koguna da ke can cikin kasa. Fiye da 100,000 km² (39,000 mi²) na ƙasa ya nutse, wanda da gaske ya ba jikin ruwa siffa ta yau.

Dokta Ryan da Dokta Pittman sun ba da sanarwar cewa wannan ambaliya tana da mummunan sakamako ga mutanen da ke zaune a bakin tekun Black Sea. Suna hasashen cewa mutanen da ambaliyar ruwa ta tilasta musu barin gonakinsu na da alhakin yaduwar noma zuwa Turai da ci gaban noma da ban ruwa zuwa kudu, a Anatoliya da Mesopotamiya. Wadannan sauye-sauyen al'adu sun faru ne a daidai lokacin da tashin Tekun Bahar Rum. A cikin shekaru 200 masu zuwa, matsugunan noma sun fara bayyana a karon farko a cikin kwaruruka na koguna da filayen tsakiyar Turai.

Marubutan binciken sun ba da shawarar cewa an ba da tarihin ambaliya ta Bahar Maliya daga tsara zuwa tsara, bayan an gano matsayinsa a cikin Littafi Mai-Tsarki a matsayin Tufana Nuhu. Wasu masana kimiyya ba sa son cuɗanyar addini da kimiyya, kuma sun yi ta suka mai ƙarfi. Wasu masana kimiyya sun yi sabani da labarin cewa halittar teku a lokacin ne kawai ko kuma ambaliya ta kasance kwatsam kuma ta yi yawa. Daya daga cikin mawallafin binciken, W. Ryan ya sake yin magana game da wannan batu a wani binciken.^(ref.) Ya bayyana cewa: "Abin da aka fi sani da masu bincike daban-daban shine bambancin matakin kusan shekaru 7.5 da suka wuce wanda ya raba matakin teku na Bahar Black daga farkon matakan ruwa." Mai binciken ya kara da cewa binciken wani cibiya daga kasan tekun Black Sea ya nuna cewa kimanin shekaru dubu 8.8 da suka gabata sinadarin strontium da ke cikin ruwa ya karu, wanda hakan ke nufin ko a lokacin ne ruwan tekun Mediterrenean ya malala cikin tabkin a wasu adadi. Har ila yau, ainihin ya nuna cewa, shekaru dubu 8.8 da suka wuce, akwai kwayoyin halitta da ke da halayyar ruwa a cikin Black Sea, amma tun shekaru 7.5 da suka wuce yawanci kwayoyin halittu suna rayuwa.

Bisa ga tebur, sake saitin ya kamata ya faru a shekara ta 5564 BC. Bayan yin la'akari da bambancin zagayowar, ya kamata ya kasance daidai a cikin shekaru 5564-5563 BC. A cikin taken binciken nasu, masu binciken sun sanya kwanan watan BP na tsawon kilo 7.5, wanda ke nufin cewa sun yi tarihin ambaliya zuwa 5551 BC. Wannan yana kusa da shekarar da ake sa ran sake saiti. Masanan kimiyyar sun dogara ne da radiyon da ake dangantawa da ragowar mussels da aka samu a saman benen teku tun lokacin da aka yi ambaliya. Dating na samfurori daban-daban ya haifar da sakamako masu zuwa: 7470 BP, 7500 BP, 7510 BP, 7510 BP, da 7580 BP. Masu binciken sun ƙididdige matsakaicin matsakaicin waɗannan sakamakon, wato, 7514 BP, sannan suka haɗa shi har zuwa 7500 BP, waɗanda suka haɗa a cikin taken binciken. Duk da haka, yana da daraja a lura cewa sakamakon kafin zagaye - 7514 BP (5565 BC) - kusan daidai daidai da shekarar da aka ba a cikin tebur! Bambanci shine kawai shekara guda! Za ka ga cewa soyayyar masanan kasa na iya zama daidai idan ba a kan kuskuren lissafin tarihin da masana tarihi suka kafa ba (tsakiya da gajeru na zamanin Bronze ne kawai). An sami wani sake saiti!

Yana da daraja la'akari da dalilin da ya sa ba zato ba tsammani ruwan teku ya shiga cikin tafkin Black Sea, kuma dalilin da ya sa wannan ya faru daidai a lokacin sake saiti. Mashigin Bosporus yana cikin yankin girgizar ƙasa, kusa da iyakar faranti na tectonic. Ina tsammanin lallai an sami girgizar ƙasa mai ƙarfi wanda faranti na tectonic suka rabu, suna buɗe mashigin kuma suna barin ruwa ya mamaye. Wataƙila an sami ƙarin bala'o'i daban-daban a lokacin wannan sake saitin, amma ruwan sama ne kawai ya yi girma har sakamakonsa ya rayu tsawon dubban shekaru.

Canjin shekarun Greenland zuwa shekarun Northgrippian transiton

Sources: An rubuta bisa ga Wikipedia (8.2-kiloyear event) da sauran kafofin.

Wani sake saiti ya fito daga tarihi kimanin shekaru 676 kafin ambaliyar Tekun Bahar Maliya. Teburin yana nuna shekara ta 6240 BC a matsayin shekarar sake saiti na gaba. Amma idan muka yi la'akari da bambancin sake zagayowar, wannan sake saitin zai yiwu ya kasance daga rabi na biyu na 6240 BC zuwa rabi na biyu na 6238 BC. Kusan wannan lokacin, wani lokaci na tsawaita yanayin sanyi da ɓarkewar yanayi ba zato ba tsammani ya sake farawa, wanda masana ilimin ƙasa suka kira taron shekara 8.2. Abu ne mai ban mamaki har ma ya fi ƙarfin abin da ya faru na tsawon shekaru 4.2, kuma ya fi tsayi, yayin da ya kasance tsakanin shekaru 200 zuwa 400. Lamarin na tsawon kilo 8.2 ana kuma la'akari da iyaka tsakanin shekarun geological biyu (Greenlandian da Northgrippian). Hukumar Kula da Dabaru ta Duniya ta bayyana shekarar da wannan girgizar ta girgiza sosai. Ta hanyar ICS, taron kilo 8.2 ya fara shekaru 8236 kafin shekara ta 2000.^(ref.) wato a shekara ta 6237 BC. Wannan shine kawai shekara ɗaya ko biyu daga shekarar da yakamata a sake saitawa! Mun riga mun dawo da nisa cikin tarihi - fiye da shekaru dubu 8 baya, kuma alamun teburin har yanzu suna da ban mamaki! Masana ilimin ƙasa kuma sun cancanci yabo don samun damar kwanan wata wani lamari da ya faru shekaru dubu da yawa da suka gabata tare da irin wannan babban daidaito!

Sakamakon raguwar zafin jiki ba zato ba tsammani ya kasance a duk faɗin duniya amma ya fi tsanani a yankin Arewacin Atlantic. Rushewar yanayi yana bayyane a fili a cikin ƙwanƙolin ƙanƙara na Greenland da kuma a cikin bayanan sedimentary na Arewacin Atlantika. Ƙididdiga na yanayin sanyi ya bambanta, amma an ba da rahoton raguwar 1 zuwa 5 °C (1.8 zuwa 9.0 °F). Maƙallan da aka haƙa a cikin tsohuwar murjani reef a Indonesia suna nuna sanyin 3 °C (5.4 °F). A cikin Greenland, sanyaya ya kasance 3.3 °C a cikin ƙasa da shekaru 20. Lokacin sanyi ya kasance kusan shekaru 60.

Damina mai zafi a kan Tekun Larabawa da Afirka masu zafi sun yi rauni sosai.^(ref.) An yi rikodin yanayin bushewa a Arewacin Afirka. Gabashin Afirka ya fuskanci fari na tsawon shekaru biyar. A Yammacin Asiya, musamman a Mesofotamiya, taron na tsawon kilo 8.2 ya bayyana kansa a cikin shekaru 300 na fari da sanyi. Wannan na iya haifar da ƙirƙirar noman ban ruwa na Mesofotamiya da noman ragi, waɗanda ke da mahimmanci ga farkon samuwar azuzuwan zamantakewa da rayuwar birane. Rage ruwan sama ya kawo lokuta masu wahala ga manoma a duk Gabas ta Tsakiya. Kauyukan noma da yawa a yankin Anatoliya da kuma kusa da Crescent an yi watsi da su, yayin da wasu suka ragu. Mutane sun kasance suna ƙaura daga Gabas ta Tsakiya zuwa Turai kusan lokacin.^(ref.) A cikin Tell Sabi Abyad (Syria), an sami gagarumin canje-canjen al'adu a kusan 6200 BC, amma ba a yi watsi da sulhu ba.

Mun ga cewa wannan tsari ya sake maimaita kansa. Nan da nan kuma ba tare da gargadi ba, sanyi da fari sun bayyana a duniya. Mutane suna ƙoƙari su daidaita da yanayin canzawa. Wasu mutane sun watsar da salon taro sun koma noma. A wasu yankuna, ƙaura na mutane suna sake faruwa. A wasu wurare an batar da abubuwan tarihi na al'adun zamanin, ko kuma muna iya cewa zamanin duhu ya sake dawowa.

A cewar masana kimiyya, wannan lamari na iya kasancewa ya faru ne sakamakon kwararar ruwa mai yawa a cikin tekun Atlantika. Sakamakon rugujewar karshe na Laurentide Ice Sheet a Arewacin Amurka, ruwan narke daga tafkin Ojibway da Agassiz ya zube cikin teku. Ruwan ruwa na farko zai iya haifar da hawan matakin teku na 0.5 zuwa 4 m kuma ya rage saurin zagayawa na thermohaline. Wannan ya kasance don rage zirga-zirgar zafi zuwa arewa ta tekun Atlantika da kuma haifar da sanyi mai mahimmanci na Arewacin Atlantika. Hasashen ambaliyar ruwan narkewa ana ɗaukarsa a matsayin hasashe saboda rashin tabbas kwanansa da yankin da ba a san tasirinsa ba.

Idan bayanin da masana kimiyya suka gabatar daidai ne, to, muna magana ne game da wani lamari mai kama da ambaliyar Tekun Bahar Maliya, amma a wannan lokacin ya kamata ruwa daga manyan tafkuna ya zubo cikin teku. Wannan kuma, ya kawo cikas ga zagawar teku da kuma haifar da lokacin sanyi da fari. Amma yayin da kwararar ruwan tafkin zuwa cikin tekun na iya yin bayanin abin da ya faru na tsawon shekaru 8.2, bai bayyana musabbabin lokacin sanyaya da aka kwatanta a baya ba. Saboda haka, ina tsammanin cewa dalilin rushewar yanayin zafi na thermohaline ya bambanta. Na yi imanin dalilin shine iskar gas da aka saki daga karkashin kasa zuwa cikin teku yayin sake saiti.

Taron 9.3 kilo na shekara

Sauyin yanayi kwatsam na gaba da masana burbushin halittu suka gano ana kiransa "wakilin shekara 9.3" ko kuma wani lokacin "wakilin shekara 9.25". Ya kasance ɗaya daga cikin fitattun abubuwan da aka fi bayyana kuma ba zato ba tsammani na yanayin yanayi na Holocene, mai kama da abin da ya faru na tsawon kilo 8.2, ko da yake yana da ƙananan girma. Dukkan abubuwan biyu sun shafi Arewacin Duniya, suna haifar da fari da sanyi.

^(ref.) David F. Porinchu et al. ya yi bincike kan tasirin abubuwan da suka faru na kilo 9.3 a cikin Arctic na Kanada. Sun bayyana cewa yana nufin zafin iska na shekara-shekara ya ragu da 1.4 °C (2.5 °F) a kilo 9.3, idan aka kwatanta da 1.7 °C a kilo 8.2, dangane da matsakaicin Holocene na dogon lokaci na 9.4 °C (49) °F). Don haka wani lamari ne da ya ɗan yi rauni fiye da wanda ya saita iyakar shekarun yanayin ƙasa. Wannan binciken ya danganta canjin yanayi a tsakiyar Arctic Kanada zuwa Arewacin Atlantic. Lamarin ya zo daidai da lokutan sanyi na Arewacin Atlantika da raunin da'ira mai juyewar yanayi na Atlantic Meridional.

^(ref.) Philippe Crombé na Jami'ar Ghent ya yi nazari kan taron na tsawon kilo 9.3 a Arewa maso yammacin Turai. Ya kwanan wata taron tsakanin 9300 da 9190 BP, don haka ya dade shekaru 110. Ya gano sauye-sauyen muhalli iri-iri kamar raguwar ayyukan mura, ƙara yawan gobarar daji da canza ciyayi, da kuma sauye-sauyen al'adu masu alaƙa da fasahar lithic da zagayawa na albarkatun ƙasa. Ya lura da raguwar adadin wuraren binciken kayan tarihi daga lokacin da yanayin ya faru.

^(ref.) Pascal Flohr et al. ya yi bincike kan al'amarin na tsawon kilo 9.25 a kudu maso yammacin Asiya. Ba su sami wata shaida ba game da rugujewar al'adu ko ƙaura a kudu maso yammacin Asiya a lokacin da aka yi sanyi da ɓacin rai. Koyaya, sun sami alamun daidaitawa na gida.

Bisa ga tebur, sake saitin ya kamata ya kasance a cikin 7331 BC, ko kuma a cikin shekaru 7332-7330 BC. Biyu daga cikin binciken kimiyya da aka ambata a sama sun nuna farkon rugujewar yanayi kwatsam zuwa shekara ta 9300 BP. Nazarin na uku ya ba da shekara ta 9250 BP. Duk waɗannan shekarun suna zagaye yayin da masu bincike suka kasa tantance ainihin lokacin da ya faru. Matsakaicin waɗannan kwanakin uku shine 9283 BP, wato shekara ta 7334 BC. Bugu da ƙari, wannan yana da ban mamaki kusa da alamun tebur! Mun kawai sami sake saiti daga sama da 9 dubu da suka wuce!

Ƙarshen zamanin Ice

Masanan nazarin halittu wani lokaci suna gane ko da tsofaffin al'amuran yanayi na duniya tun daga zamanin Holocene wanda ya kawo sanyi da fari, kamar 10.3 da 11.1 kilo-year BP. Duk da haka, waɗannan al'amura ne da ba a yi bincike da kyau ba kuma aka bayyana su. Ba a san ainihin lokacin da suka fara ko kuma kamannin su ba, amma ana iya ɗauka cewa su ma suna da alaƙa da zagayowar sake saiti.

Ya zuwa yanzu, muna neman shekaru na bala'i don tabbatar da wanzuwar sake saiti na shekaru 676. Yanzu da muka tabbatar da wanzuwar zagayowar, za mu iya yin akasin haka kuma mu yi amfani da zagayowar don gano shekarar bala'in. Godiya ga ilimin sake zagayowar, zamu iya, alal misali, ƙayyade ainihin shekarar ƙarshen Ice Age!

Ice Age ya ƙare tare da wucewar lokacin sanyi na ƙarshe a tarihin Duniya, wanda ake kira Younger Dryas. Dumamar yanayi ta faru ba zato ba tsammani. Binciken ainihin ƙanƙara ya nuna cewa a cikin Greenland matsakaicin zafin jiki na shekara ya tashi da kusan 8 °C (14 °F) sama da shekaru 40 kacal.^(ref.) Amma sauyin na iya zama ma da sauri. A cewar wasu majiyoyin, bai wuce shekaru 10 ba.^(ref.) Mafi yarda da bayanin wannan saurin sauyin yanayi mai ban mamaki shine saurin zagayawa na thermohaline kwatsam. A lokacin Ice Age, wannan babban tekun da ke rarraba ruwa da zafi a duk faɗin duniya tabbas an rufe shi gaba ɗaya. Sai dai kuma, a wani lokaci, wannan bel din na jigilar teku ya kunna ba zato ba tsammani, kuma hakan ya haifar da dumamar yanayi da ma'aunin Celsius da dama. Ina tsammanin dalilin wannan taron ba komai bane illa sake saiti na cyclical. Ta hanyar amfani da hanyoyi daban-daban, masana kimiyya sun bayyana ƙarshen zamanin Ice zuwa shekaru daga 9704 BC zuwa 9580 BC.^(ref.) Bi da bi, sake zagayowar sake saiti yana nuna cewa a cikin wannan lokaci kawai shekara mai yiwuwa don bala'in duniya shine 9615±1 BC. Kuma tabbas wannan shine ainihin shekarar ƙarshen Ice Age da farkon Holocene!