A Study of the Technology Used to Distinguish Sea Ice and Seawater on the Haiyang-2A/B (HY-2A/B) Altimeter Data
When the Haiyang-2B (HY-2B) was launched into space to form a star network with the Haiyang-2A (HY-2A), it provided new data sources for the sea ice research of the Earth’s polar regions. The ability of altimeter echoes to distinguish sea ice and sea water is usable in operational ice charting. In t...
Published in: | Remote Sensing |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
MDPI AG
2019
|
Subjects: | |
Online Access: | https://doi.org/10.3390/rs11121490 https://doaj.org/article/402d9aee2a194ea8946b6bf0b315ff75 |
id |
ftdoajarticles:oai:doaj.org/article:402d9aee2a194ea8946b6bf0b315ff75 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:402d9aee2a194ea8946b6bf0b315ff75 2023-05-15T13:52:51+02:00 A Study of the Technology Used to Distinguish Sea Ice and Seawater on the Haiyang-2A/B (HY-2A/B) Altimeter Data Chengfei Jiang Mingsen Lin Hao Wei 2019-06-01T00:00:00Z https://doi.org/10.3390/rs11121490 https://doaj.org/article/402d9aee2a194ea8946b6bf0b315ff75 EN eng MDPI AG https://www.mdpi.com/2072-4292/11/12/1490 https://doaj.org/toc/2072-4292 2072-4292 doi:10.3390/rs11121490 https://doaj.org/article/402d9aee2a194ea8946b6bf0b315ff75 Remote Sensing, Vol 11, Iss 12, p 1490 (2019) Haiyang-2 (HY-2) radar altimeter Arctic Antarctic sea ice seawater Science Q article 2019 ftdoajarticles https://doi.org/10.3390/rs11121490 2022-12-30T20:19:40Z When the Haiyang-2B (HY-2B) was launched into space to form a star network with the Haiyang-2A (HY-2A), it provided new data sources for the sea ice research of the Earth’s polar regions. The ability of altimeter echoes to distinguish sea ice and sea water is usable in operational ice charting. In this research study, the level 1B (L1B) data of HY-2A/B altimeter from November 2018 was used to analyze the altimeter waveforms from the polar regions. The Suboptimal Maximum Likelihood Estimation (SMLE) and Offset Center of Gravity (OCOG) tracking packages could maintain the waveform characteristics of diffused and quasi-specular surfaces by comparison. Also, they could be utilized to distinguish sea ice from seawater in the polar regions. It was determined that the types of echoes obtained from the seawater were diffuse. Also, some “ocean-like” waveform data had existed for the old ice formations in the Arctic regions during the study period. The types of echoes obtained from Arctic sea ice were found to be mainly quasi-specular. In the present study, three methods (Threshold segmentation, K-nearest-neighbor (KNN), and Lib-Support Vector machine (LIBSVM)) with four waveform parameters (Automatic Gain Control (AGC) and Pulse Peaking (PP) values of the Ku and C Bands) were adopted to distinguish between the sea ice and seawater areas. The accuracy rate of the separation results for the LIBSVM except band Ku from HY-2B ALT was found to be less than 40% in Antarctic. Meanwhile, the other two methods were observed to have maintained the waveforms correctly at accuracy rates of approximately 80% in Antarctic and the Arctic. In addition, the observed distinguishing errors were located in the regions of the old ice of the Arctic region. In addition, due to the summer melting processes, the large number of ice floes and the snow cover had made it difficult to distinguish the seawater and sea ice in the Antarctic regions. Article in Journal/Newspaper Antarc* Antarctic Arctic Sea ice Directory of Open Access Journals: DOAJ Articles Arctic Antarctic The Antarctic Remote Sensing 11 12 1490 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Haiyang-2 (HY-2) radar altimeter Arctic Antarctic sea ice seawater Science Q |
spellingShingle |
Haiyang-2 (HY-2) radar altimeter Arctic Antarctic sea ice seawater Science Q Chengfei Jiang Mingsen Lin Hao Wei A Study of the Technology Used to Distinguish Sea Ice and Seawater on the Haiyang-2A/B (HY-2A/B) Altimeter Data |
topic_facet |
Haiyang-2 (HY-2) radar altimeter Arctic Antarctic sea ice seawater Science Q |
description |
When the Haiyang-2B (HY-2B) was launched into space to form a star network with the Haiyang-2A (HY-2A), it provided new data sources for the sea ice research of the Earth’s polar regions. The ability of altimeter echoes to distinguish sea ice and sea water is usable in operational ice charting. In this research study, the level 1B (L1B) data of HY-2A/B altimeter from November 2018 was used to analyze the altimeter waveforms from the polar regions. The Suboptimal Maximum Likelihood Estimation (SMLE) and Offset Center of Gravity (OCOG) tracking packages could maintain the waveform characteristics of diffused and quasi-specular surfaces by comparison. Also, they could be utilized to distinguish sea ice from seawater in the polar regions. It was determined that the types of echoes obtained from the seawater were diffuse. Also, some “ocean-like” waveform data had existed for the old ice formations in the Arctic regions during the study period. The types of echoes obtained from Arctic sea ice were found to be mainly quasi-specular. In the present study, three methods (Threshold segmentation, K-nearest-neighbor (KNN), and Lib-Support Vector machine (LIBSVM)) with four waveform parameters (Automatic Gain Control (AGC) and Pulse Peaking (PP) values of the Ku and C Bands) were adopted to distinguish between the sea ice and seawater areas. The accuracy rate of the separation results for the LIBSVM except band Ku from HY-2B ALT was found to be less than 40% in Antarctic. Meanwhile, the other two methods were observed to have maintained the waveforms correctly at accuracy rates of approximately 80% in Antarctic and the Arctic. In addition, the observed distinguishing errors were located in the regions of the old ice of the Arctic region. In addition, due to the summer melting processes, the large number of ice floes and the snow cover had made it difficult to distinguish the seawater and sea ice in the Antarctic regions. |
format |
Article in Journal/Newspaper |
author |
Chengfei Jiang Mingsen Lin Hao Wei |
author_facet |
Chengfei Jiang Mingsen Lin Hao Wei |
author_sort |
Chengfei Jiang |
title |
A Study of the Technology Used to Distinguish Sea Ice and Seawater on the Haiyang-2A/B (HY-2A/B) Altimeter Data |
title_short |
A Study of the Technology Used to Distinguish Sea Ice and Seawater on the Haiyang-2A/B (HY-2A/B) Altimeter Data |
title_full |
A Study of the Technology Used to Distinguish Sea Ice and Seawater on the Haiyang-2A/B (HY-2A/B) Altimeter Data |
title_fullStr |
A Study of the Technology Used to Distinguish Sea Ice and Seawater on the Haiyang-2A/B (HY-2A/B) Altimeter Data |
title_full_unstemmed |
A Study of the Technology Used to Distinguish Sea Ice and Seawater on the Haiyang-2A/B (HY-2A/B) Altimeter Data |
title_sort |
study of the technology used to distinguish sea ice and seawater on the haiyang-2a/b (hy-2a/b) altimeter data |
publisher |
MDPI AG |
publishDate |
2019 |
url |
https://doi.org/10.3390/rs11121490 https://doaj.org/article/402d9aee2a194ea8946b6bf0b315ff75 |
geographic |
Arctic Antarctic The Antarctic |
geographic_facet |
Arctic Antarctic The Antarctic |
genre |
Antarc* Antarctic Arctic Sea ice |
genre_facet |
Antarc* Antarctic Arctic Sea ice |
op_source |
Remote Sensing, Vol 11, Iss 12, p 1490 (2019) |
op_relation |
https://www.mdpi.com/2072-4292/11/12/1490 https://doaj.org/toc/2072-4292 2072-4292 doi:10.3390/rs11121490 https://doaj.org/article/402d9aee2a194ea8946b6bf0b315ff75 |
op_doi |
https://doi.org/10.3390/rs11121490 |
container_title |
Remote Sensing |
container_volume |
11 |
container_issue |
12 |
container_start_page |
1490 |
_version_ |
1766257609830039552 |