Un nuovo modello matematico smentisce che il riscaldamento accelerato dell'Artico stia aumentando gli episodi di freddo intenso simili a quelli che hanno flagellato gli Stati Uniti lo scorso gennaio. Al contrario, i dati dimostrano che si sta riducendo la variabilità delle temperature autunnali e invernali alle medie e alte latitudini dell'emisfero settentrionale.
E’ questa la conclusione dello studio pubblicato su Nature Climate Change dal matematico James A. Screen dell'università di Exeter, in Gran Bretagna.
Il ricercatore ha preso in esame i dati relativi alle temperature autunnali e invernali registrate nell'emisfero settentrionale dagli anni Ottanta ad oggi scoprendo che stanno diventando sempre più costanti. Questo sarebbe dovuto al fatto che i venti settentrionali e i giorni freddi ad essi collegati si stanno riscaldando più rapidamente rispetto ai venti meridionali e ai relativi giorni caldi.
Red.MM/ATS/Swing
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