From 1/4° to 1/8°: Influence of Spatial Resolution on Eddy Detection Using Altimeter Data
A substantial portion of ocean eddies, especially small ones, may be missed due to insufficient spatial or temporal sampling by satellite altimetry. In order to illustrate the influence of spatial resolution on eddy detection, this study provides a comparison of eddy identification, tracking, and an...
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MDPI AG
2021-12-01
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| Series: | Remote Sensing |
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| Online Access: | https://www.mdpi.com/2072-4292/14/1/149 |
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| author | Yinuo Wang Xiaoyan Chen Guiyan Han Pingping Jin Jie Yang |
| author_facet | Yinuo Wang Xiaoyan Chen Guiyan Han Pingping Jin Jie Yang |
| author_sort | Yinuo Wang |
| collection | DOAJ |
| description | A substantial portion of ocean eddies, especially small ones, may be missed due to insufficient spatial or temporal sampling by satellite altimetry. In order to illustrate the influence of spatial resolution on eddy detection, this study provides a comparison of eddy identification, tracking, and analysis between two sets of merged altimeter data with spatial resolutions of 1/4° and 1/8°. One main study area (the Mediterranean Sea), and three confirmatory areas (the South-China Sea, the North-West Pacific, and the South-East Pacific) are chosen. The results show that the number and density of eddies captured by the 1/8° data are about twice as much as those captured by the 1/4° data, while the ratios of corresponding eddy parameters, i.e., radius, amplitude, (eddy kinetic energy (EKE)) are about 0.6–0.8 (1.3) for the two datasets (1/8° ÷ 1/4°). Long-term eddy tracking (1993–2018) is conducted in the Mediterranean Sea, indicating that the improvement in spatial resolution will increase the observed values of both the lifetime and the propagation distance of robust eddies. The number of eddies identified using the 1/4° data only accounts for ~30% to 60% of those identified using the 1/8° data. However, for eddies that can be detected using the two datasets, ~5% to 10% present errors (i.e., confusion). In comparison between the four regions, we find that for the enclosed seas with complex conditions, the increase in spatial resolution may lead to more significant improvements in the efficiency and accuracy of eddy detection. |
| first_indexed | 2024-03-10T03:23:12Z |
| format | Article |
| id | doaj.art-82708b430d6847b692344ab3b5400513 |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-03-10T03:23:12Z |
| publishDate | 2021-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-82708b430d6847b692344ab3b54005132023-11-23T12:13:54ZengMDPI AGRemote Sensing2072-42922021-12-0114114910.3390/rs14010149From 1/4° to 1/8°: Influence of Spatial Resolution on Eddy Detection Using Altimeter DataYinuo Wang0Xiaoyan Chen1Guiyan Han2Pingping Jin3Jie Yang4College of Marine Technology, Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, ChinaCollege of Marine Technology, Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, ChinaCollege of Marine Technology, Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, ChinaCollege of Marine Technology, Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, ChinaCollege of Marine Technology, Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, ChinaA substantial portion of ocean eddies, especially small ones, may be missed due to insufficient spatial or temporal sampling by satellite altimetry. In order to illustrate the influence of spatial resolution on eddy detection, this study provides a comparison of eddy identification, tracking, and analysis between two sets of merged altimeter data with spatial resolutions of 1/4° and 1/8°. One main study area (the Mediterranean Sea), and three confirmatory areas (the South-China Sea, the North-West Pacific, and the South-East Pacific) are chosen. The results show that the number and density of eddies captured by the 1/8° data are about twice as much as those captured by the 1/4° data, while the ratios of corresponding eddy parameters, i.e., radius, amplitude, (eddy kinetic energy (EKE)) are about 0.6–0.8 (1.3) for the two datasets (1/8° ÷ 1/4°). Long-term eddy tracking (1993–2018) is conducted in the Mediterranean Sea, indicating that the improvement in spatial resolution will increase the observed values of both the lifetime and the propagation distance of robust eddies. The number of eddies identified using the 1/4° data only accounts for ~30% to 60% of those identified using the 1/8° data. However, for eddies that can be detected using the two datasets, ~5% to 10% present errors (i.e., confusion). In comparison between the four regions, we find that for the enclosed seas with complex conditions, the increase in spatial resolution may lead to more significant improvements in the efficiency and accuracy of eddy detection.https://www.mdpi.com/2072-4292/14/1/149oceanic eddieshigh precision altimetry dataeddy identification and trackingeddy characteristic analysisthe Mediterranean Sea |
| spellingShingle | Yinuo Wang Xiaoyan Chen Guiyan Han Pingping Jin Jie Yang From 1/4° to 1/8°: Influence of Spatial Resolution on Eddy Detection Using Altimeter Data Remote Sensing oceanic eddies high precision altimetry data eddy identification and tracking eddy characteristic analysis the Mediterranean Sea |
| title | From 1/4° to 1/8°: Influence of Spatial Resolution on Eddy Detection Using Altimeter Data |
| title_full | From 1/4° to 1/8°: Influence of Spatial Resolution on Eddy Detection Using Altimeter Data |
| title_fullStr | From 1/4° to 1/8°: Influence of Spatial Resolution on Eddy Detection Using Altimeter Data |
| title_full_unstemmed | From 1/4° to 1/8°: Influence of Spatial Resolution on Eddy Detection Using Altimeter Data |
| title_short | From 1/4° to 1/8°: Influence of Spatial Resolution on Eddy Detection Using Altimeter Data |
| title_sort | from 1 4° to 1 8° influence of spatial resolution on eddy detection using altimeter data |
| topic | oceanic eddies high precision altimetry data eddy identification and tracking eddy characteristic analysis the Mediterranean Sea |
| url | https://www.mdpi.com/2072-4292/14/1/149 |
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