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  • Accepted Manuscript: Going with the floe: tracking CESM Large Ensemble sea ice in the Arctic provides context for ship-based observations
Title: Going with the floe: tracking CESM Large Ensemble sea ice in the Arctic provides context for ship-based observations
Abstract. In recent decades, Arctic sea ice has shifted toward ayounger, thinner, seasonal ice regime. Studying and understanding this“new” Arctic will be the focus of a year-long ship campaign beginning inautumn 2019. Lagrangian tracking of sea ice floes in the Community EarthSystem Model Large Ensemble (CESM-LE) during representative “perennial”and “seasonal” time periods allows for understanding of the conditionsthat a floe could experience throughout the calendar year. These modeltracks, put into context a single year of observations, provide guidance onhow observations can optimally shape model development, and how climatemodels could be used in future campaign planning. The modeled floe tracksshow a range of possible trajectories, though a Transpolar Drift trajectoryis most likely. There is also a small but emerging possibility of high-risktracks, including possible melt of the floe before the end of a calendaryear. We find that a Lagrangian approach is essential in order to correctlycompare the seasonal cycle of sea ice conditions between point-basedobservations and a model. Because of high variability in the melt season seaice conditions, we recommend in situ sampling over a large range of ice conditionsfor a more complete understanding of how ice type and surface conditionsaffect the observed processes. We find that sea ice predictability emergesrapidly more » during the autumn freeze-up and anticipate that process-basedobservations during this period may help elucidate the processes leading tothis change in predictability. « less
Authors:
; ; ; ; ;
Award ID(s):
1724748
Publication Date:
NSF-PAR ID:
10194352
Journal Name:
The Cryosphere
Volume:
14
Issue:
4
Page Range or eLocation-ID:
1259 to 1271
ISSN:
1994-0424
Sponsoring Org:
National Science Foundation
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