Inter-comparison and evaluation of Arctic sea ice type products

• Published in: The Cryosphere
• Main Authors: Y. Ye, Y. Luo, Y. Sun, M. Shokr, S. Aaboe, F. Girard-Ardhuin, F. Hui, X. Cheng, Z. Chen
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2023
• Subjects: Environmental sciences; GE1-350; Geology; QE1-996.5; Arctic; Climate change; National Snow and Ice Data Center; Sea ice; The Cryosphere
• Online Access: https://doi.org/10.5194/tc-17-279-2023; https://doaj.org/article/28511a6596d34c2cbb510414c5a34d4f

Arctic sea ice type (SITY) variation is a sensitive indicator of climate change. However, systematic inter-comparison and analysis for SITY products are lacking. This study analysed eight daily SITY products from five retrieval approaches covering the winters of 1999–2019, including purely radiometer-based (C3S-SITY), scatterometer-based (KNMI-SITY and IFREMER-SITY) and combined ones (OSISAF-SITY and Zhang-SITY). These SITY products were inter-compared against a weekly sea ice age product (i.e. NSIDC-SIA – National Snow and Ice Data Center sea ice age) and evaluated with five synthetic aperture radar (SAR) images. The average Arctic multiyear ice (MYI) extent difference between the SITY products and NSIDC-SIA varies from <math xmlns="http://www.w3.org/1998/Math/MathML" id="M1" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>-</mo><mn mathvariant="normal">1.32</mn><mo>×</mo><msup><mn mathvariant="normal">10</mn><mn mathvariant="normal">6</mn></msup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="59pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="2aa22a9ffdc850c2c372527cc31a192d"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="tc-17-279-2023-ie00001.svg" width="59pt" height="14pt" src="tc-17-279-2023-ie00001.png"/></svg:svg> to 0.49×10 6 km 2 . Among them, KNMI-SITY and Zhang-SITY in the QuikSCAT (QSCAT) period (2002–2009) agree best with NSIDC-SIA and perform the best, with the smallest bias of <math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>-</mo><mn mathvariant="normal">0.001</mn><mo>×</mo><msup><mn mathvariant="normal">10</mn><mn mathvariant="normal">6</mn></msup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="65pt" height="14pt" ...