Nøgleord
Ice Paleoclimate
Climate Proxies
Citation/Eksport
Resumé
Fortidens klimaændringer i Arktis – herunder abrupt opvarmning og skift i havisens udbredelse – analyseres her i dybden med fokus på nye proxier som IP25, Br-excess og jod i iskerner. Forfatterne viser, hvordan proxydata fra sedimentkerner og iskerner sammenkædes til et tidsopløst billede af havisens respons på klimaændringer, fra Eem til Holocæn. Artiklen dokumenterer havisens nøglerolle i klimafeedbacks og fremhæver nødvendigheden af, at CMIP-klimamodeller bedre repræsenterer havisdynamik. Særligt bemærkelsesværdigt er sammenligningerne mellem DO-events og moderne opvarmning, hvor samme opvarmningshastigheder nu observeres. En vigtig artikel for klimafysikere og modellører.
Referencer
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