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  • Accepted Manuscript: Estimating the sea ice floe size distribution using satellite altimetry: theory, climatology, and model comparison
Title: Estimating the sea ice floe size distribution using satellite altimetry: theory, climatology, and model comparison
Abstract. In sea-ice-covered areas, the sea ice floe size distribution (FSD) plays an important role in many processes affecting the coupled sea–ice–ocean–atmosphere system. Observations of the FSD are sparse – traditionally taken via a painstaking analysis of ice surface photography – and the seasonal and inter-annual evolution of floe size regionally and globally is largely unknown. Frequently, measured FSDs are assessed using a single number, the scaling exponent of the closest power-law fit to the observed floe size data, although in the absence of adequate datasets there have been limited tests of this “power-law hypothesis”. Here we derive and explain a mathematical technique for deriving statistics of the sea ice FSD from polar-orbiting altimeters, satellites with sub-daily return times to polar regions with high along-track resolutions. Applied to the CryoSat-2 radar altimetric record, covering the period from 2010 to 2018, and incorporating 11 million individual floe samples, we produce the first pan-Arctic climatology and seasonal cycle of sea ice floe size statistics. We then perform the first pan-Arctic test of the power-law hypothesis, finding limited support in the range of floe sizes typically analyzed in photographic observational studies. We compare the seasonal variability in observed floe size to fully coupled more » climate model simulations including a prognostic floe size and thickness distribution and coupled wave model, finding good agreement in regions where modeled ocean surface waves cause sea ice fracture. « less
Authors:
; ; ; ; ; ; ; ;
Award ID(s):
1643431
Publication Date:
NSF-PAR ID:
10142151
Journal Name:
The Cryosphere
Volume:
13
Issue:
11
Page Range or eLocation-ID:
2869 to 2885
ISSN:
1994-0424
Sponsoring Org:
National Science Foundation
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