@article{oai:kitami-it.repo.nii.ac.jp:02000356,
 author = {Noriaki Kimura and Kazutaka Tateyama and Kazutoshi Sato and Richard A. Krishfield and Hajime Yamaguchi},
 journal = {Polar Research},
 month = {},
 note = {In summer 2018, thick sea ice blocked the mouth of the Amundsen Gulf (AG), Canada,  obstructing  shipping  through  the  North-west  Passage.  This  study  analysed multi-year ice motion to investigate the source of this thick ice and the  reasons  for  its  unusual  movement.  For  this  purpose,  a  daily  multi-year  ice distribution product was generated by ice tracking using gridded daily sea-ice velocities (2003–2018) derived from the AMSR-E and AMSR-2 data. From autumn 2017 to summer 2018, the area of multi-year ice extended westward to  the  Beaufort  Sea  and  then  migrated  towards  the  AG  mouth.  The  primary  cause  of  the  unusual  ice  cover  was  anomalous  AG-ward  wind  in  September  2018. It is known that multi-year ice has become increasingly moveable over the past decades, as indicated by the increasing wind factor (i.e., ratio of ice-drift speed and wind speed), but the unusual ice motion in the summer of 2018 cannot be explainable by the wind factor alone. Accurately, predicting monthly wind and monitoring old thick ice will reduce the risk posed by thick Arctic sea ice to shipping.},
 title = {Unusual drift behaviour of multi-year sea ice in the Beaufort Sea during summer 2018},
 volume = {39},
 year = {2020}
}