N'ime ihe atụ a, ikuku ikuku "greenhouse gases" na-eme ka oke osimiri ghara ifriizi mgbe anyanwụ na-etolite ọhụrụ nwere naanị 70% nke ìhè ya ugbu a. Site na 3.5 Mya, e guzobere mpaghara magnetik nke ụwa, nke nyere aka igbochi ikuku site na ifufe anyanwụ. A kpụrụ akpụ mgbe oyi akwa nke ụwa jụrụ oyi iji mepụta ihe siri ike. Ihe atụ abụọ na-akọwa oke ala na-atụ aro ma ọ bụ mmụba na-aga n'ihu ruo ụbọchị ma ọ bụ, o yikarịrị, mmụba ngwa ngwa na mmalite akụkọ ihe mere eme nke ụwa site na mpaghara ogologo oge.
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