Retrieval and parameterisation of sea-ice bulk density from airborne multi-sensor measurements


Contact
arttu.jutila [ at ] awi.de

Abstract

Knowledge of sea-ice thickness and volume depends on freeboard observations from satellite altimeters and in turn on information of snow mass and sea-ice density required for the freeboard-to-thickness conversion. These parameters, especially sea-ice density, are usually based on climatologies constructed from in situ observations made in the 1980s and earlier while contemporary and representative measurements are lacking. Our aim with this paper is to derive updated sea-ice bulk density estimates suitable for the present Arctic sea-ice cover and a range of ice types to reduce uncertainties in sea-ice thickness remote sensing. Our sea-ice density measurements are based on over 3000 km of high-resolution collocated airborne sea-ice and snow thickness and freeboard measurements in the western Arctic Ocean in 2017 and 2019. Sea-ice bulk density is derived assuming isostatic equilibrium for different ice types. Our results show higher average bulk densities for both first-year ice (FYI) and especially multi-year ice (MYI) compared to previous studies. In addition, we find a small difference between deformed and possibly unconsolidated FYI and younger MYI. We find a negative-exponential relationship between sea-ice bulk density and sea-ice freeboard and apply this parameterisation to one winter of monthly gridded CryoSat-2 sea-ice freeboard data. We discuss the suitability and the impact of the derived FYI and MYI bulk densities for sea-ice thickness retrievals and the uncertainty related to the indirect method of measuring sea-ice bulk density. The results suggest that retrieval algorithms be adapted to changes in sea-ice density and highlight the need of future studies to evaluate the impact of density parameterisation on the full sea-ice thickness data record.



Item Type
Article
Authors
Divisions
Primary Division
Programs
Primary Topic
Helmholtz Cross Cutting Activity (2021-2027)
N/A
Peer revision
Peer-reviewed, Web of Science / Scopus
Publication Status
Published
Eprint ID
55566
DOI 10.5194/tc-16-259-2022

Cite as
Jutila, A. , Hendricks, S. , Ricker, R. , von Albedyll, L. , Krumpen, T. and Haas, C. (2022): Retrieval and parameterisation of sea-ice bulk density from airborne multi-sensor measurements , The Cryosphere, 16 (1), pp. 259-275 . doi: 10.5194/tc-16-259-2022


Download
[thumbnail of tc-16-259-2022.pdf]
Preview
PDF
tc-16-259-2022.pdf

Download (8MB) | Preview

Share


Citation

Geographical region

Research Platforms

Campaigns
POLAR 5 > P5_205_PAMARCMIP_2017
POLAR 6 > P6_217_ICEBIRD_2019


Actions
Edit Item Edit Item