Work

Advanced Algorithm for Continuous Melt Onset Detection on Arctic Sea Ice

Year: 2025

Type: article

Abstract: Expansion of the Arctic melting season with an earlier melt onset date (MOD) is a well-known indicator of Arctic warming. Since 1979, the pan-Arctic MOD distributions usually have been estimated using passive satellite microwave radiometer observations. However, there is a poor agreement in MOD between previous MOD detection algorithms based on passive microwave measurements, raising doubts regarding the accuracy of their MOD products. Thus, this study developed a new MOD algorithm, namely TBmax algorithm, to improve the estimation accuracy of continuous melt onset. The TBmax algorithm utilizes the microwave radiation characteristics of sea ice, and the daily brightness temperature time series shows their maximum brightness temperature on MOD. By using Advanced Microwave Scanning Radiometer 2 brightenss temperature data, the pan-Arctic MOD distributions estimated from 2013 to 2021 using the TBmax algorithm successfully reproduced a feature of sea ice melting that mainly during May or June over the Arctic, including the late melting tendency of ice at high latitudes and multiyear ice. The results of the inter-comparison with other MODs from previous MOD algorithms indicated that TBmax MODs showed stable and moderate values compared to other MODs. Furthermore, validation with two different datasets (ice mass balance buoy and reanalysis data) suggested that the TBmax MODs showed superior performance in both cases (biases of 0.1 and -4.5 days vs. buoys and reanalysis data, respectively), compared to other previous algorithms. As MOD can provide information about surface emissivity and the energy budget of the sea ice, the improved MOD may contribute to a more precise analysis of Arctic environment change and enhanced estimation of sea ice parameters.

Source: IEEE Transactions on Geoscience and Remote Sensing

DOI: 10.1109/tgrs.2025.3560261

Authors: Jong-Min Kim, Hyun-Cheol Kim, Jeong-Won Park, Jinku Park, Minji Seo, Sang-Moo Lee

Institutions: Korea Polar Research Institute, Seoul National University

Language: English

Topic: Arctic and Antarctic ice dynamics

Subfield: Atmospheric Science

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDG: Climate action

Open Access status: green

Funder: Korea Polar Research Institute