دورية أكاديمية

Glacier melt detection at different sites of Greenland ice sheet using dual-polarized Sentinel-1 images

التفاصيل البيبلوغرافية
العنوان: Glacier melt detection at different sites of Greenland ice sheet using dual-polarized Sentinel-1 images
المؤلفون: Gang Li, Xiao Chen, Hui Lin, Andrew Hooper, Zhuoqi Chen, Xiao Cheng
المصدر: Geo-spatial Information Science, Vol 27, Iss 3, Pp 728-743 (2024)
بيانات النشر: Taylor & Francis Group, 2024.
سنة النشر: 2024
المجموعة: LCC:Mathematical geography. Cartography
LCC:Geodesy
مصطلحات موضوعية: Glacier melt, Greenland ice sheet, Sentinel-1, backscatter coefficient, radar glacier zones, Mathematical geography. Cartography, GA1-1776, Geodesy, QB275-343
الوصف: Synectic Aperture Radar (SAR) backscatter coefficient is sensitive to glacier surface physical characteristic changes, including the states of melting and refreezing, but it is also sensitive to incidence angle variation. This study explores the capability of monitoring Greenland Ice Sheet (GrIS) melting status with Sentinel-1 dual-polarized images by referring to Automatic Weather Station (AWS) records. Sentinel-1 SAR images at five coastal regions of the GrIS are obtained from 2017 to 2021. The backscatter coefficients are normalized to an incidence angle of 30° with an empirical model. Time series of five backscatter coefficients profiles covering AWS illustrates different patterns of the ice surface dielectric constant dynamics in different elevations. The wet snow radar zone shows clear backscatter coefficients decreasing during the melting seasons, but the bare ice radar zone behaves more complexly during the melting seasons. The numbers of melting days at different elevations are also derived for each profile based on −3 dB backscatter coefficient decrease of HH and/or HV polarization, showing the heterogeneous ablation processes over the GrIS. The daily maximum 2 m air temperature on two consecutive days (before and on the SAR acquisition day) exceeds 0°C, and the daily average 2 m air temperature exceeds −0.5°C on the SAR acquisition day that was recorded by the AWS finds good agreements with the −3 dB decrease of the backscatter coefficients, suggesting the GrIS surface melting can be well captured by dual-polarized Sentinel-1 C-band SAR images. The overall agreement and Kappa coefficients are mostly better than 0.85 and 0.70, respectively, for HH images and 0.80 and 0.60, respectively, for HV images, suggesting a better performance of the co-polarized image. High temporal resolution and wide-swath SAR sequence imagery provide suitable data sources for monitoring glacier surface melting-refreezing stats; further analysis is requested to quantitatively link the volume of melting with backscatter coefficient and other SAR data sources.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 10095020
1993-5153
1009-5020
Relation: https://doaj.org/toc/1009-5020; https://doaj.org/toc/1993-5153
DOI: 10.1080/10095020.2023.2252034
URL الوصول: https://doaj.org/article/f7218a1e19ea4caf84be046b1a973afe
رقم الأكسشن: edsdoj.f7218a1e19ea4caf84be046b1a973afe
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:10095020
19935153
DOI:10.1080/10095020.2023.2252034