title: Major cause of unprecedented Arctic warming in January 2016: Critical role of an Atlantic windstorm.
abstract: In January 2016, the Arctic experienced an extremely anomalous warming event after an extraordinary increase in air temperature at the end of 2015. During this event, a strong intrusion of warm and moist air and an increase in downward longwave radiation, as well as a loss of sea ice in the Barents and Kara seas, were observed. Observational analyses revealed that the abrupt warming was triggered by the entry of a strong Atlantic windstorm into the Arctic in late December 2015, which brought enormous moist and warm air masses to the Arctic. Although the storm terminated at the eastern coast of Greenland in late December, it was followed by a prolonged blocking period in early 2016 that sustained the extreme Arctic warming. Numerical experiments indicate that the warming effect of sea ice loss and associated upward turbulent heat fluxes are relatively minor in this event. This result suggests the importance of the synoptically driven warm and moist air intrusion into the Arctic as a primary contributing factor of this extreme Arctic warming event.
authors.affiliation: Korea Polar Research Institute, Incheon, South Korea.
authors.forename: Baek-Min
authors.initials: BM
authors.lastname: Kim
authors.affiliation: Korea Polar Research Institute, Incheon, South Korea.
authors.forename: Ja-Young
authors.initials: JY
authors.lastname: Hong
authors.affiliation: Korea Polar Research Institute, Incheon, South Korea.
authors.forename: Sang-Yoon
authors.initials: SY
authors.lastname: Jun
authors.affiliation: University of Alaska, Fairbanks, USA.
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Korea Polar Research Institute, Incheon, South Korea.
authors.forename: Hataek
authors.initials: H
authors.lastname: Kwon
authors.affiliation: Korea Polar Research Institute, Incheon, South Korea.
authors.forename: Seong-Joong
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Korea Polar Research Institute, Incheon, South Korea.
authors.forename: Joo-Hong
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Seoul National University, Seoul, South Korea.
authors.forename: Sang-Woo
authors.initials: SW
authors.lastname: Kim
authors.affiliation: Korea Meteorological Administration, Seoul, South Korea.
authors.forename: Hyun-Kyung
authors.initials: HK
authors.lastname: Kim