Influence of North Pacific decadal variability on the western Canadian Arctic over the past 700 years

TitleInfluence of North Pacific decadal variability on the western Canadian Arctic over the past 700 years
Publication TypeJournal Article
Year of Publication2017
AuthorsLapointe, François, Francus Pierre, Lamoureux Scott F., Vuille Mathias, Jenny Jean-Philippe, Bradley Raymond S., and Massa Charly
JournalClimate of the Past
Volume13
Issue4
Pagination411 - 420
Date PublishedApril-21-2017
KeywordsArctic, climate variability, FORCAsT, sea ice
Abstract

Understanding how internal climate variability influences arctic regions is required to better forecast future global climate variations. This paper investigates an annually-laminated (varved) record from the western Canadian Arctic and finds that the varves are negatively correlated with both the instrumental Pacific Decadal Oscillation (PDO) during the past century and also with reconstructed PDO over the past 700 years, suggesting drier Arctic conditions during high-PDO phases, and vice versa. These results are in agreement with known regional teleconnections, whereby the PDO is negatively and positively correlated with summer precipitation and mean sea level pressure respectively. This pattern is also evident during the positive phase of the North Pacific Index (NPI) in autumn. Reduced sea-ice cover during summer–autumn is observed in the region during PDO− (NPI+) and is associated with low-level southerly winds that originate from the northernmost Pacific across the Bering Strait and can reach as far as the western Canadian Arctic. These climate anomalies are associated with the PDO− (NPI+) phase and are key factors in enhancing evaporation and subsequent precipitation in this region of the Arctic. Collectively, the sedimentary evidence suggests that North Pacific climate variability has been a persistent regulator of the regional climate in the western Canadian Arctic. Since projected sea-ice loss will contribute to enhanced future warming in the Arctic, future negative phases of the PDO (or NPI+) will likely act to amplify this positive feedback.

URLhttps://www.clim-past.net/13/411/2017/
DOI10.5194/cp-13-411-2017
Short TitleClim. Past