{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,9]],"date-time":"2025-12-09T08:28:30Z","timestamp":1765268910015,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2023,10,3]],"date-time":"2023-10-03T00:00:00Z","timestamp":1696291200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["62225104","62001021"],"award-info":[{"award-number":["62225104","62001021"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Weather radar plays an important role in monitoring aerial animal migration, providing a stable data source for biological studies with large-scale coverage and consecutive-time samples. The accurate estimation of bird density from weather radar echoes is fundamental for quantitative biological studies. We analyzed the bird observation model in weather radar, and proposed a method to build the bird quantification model by jointly utilizing dual-polarization Doppler weather radar and scanning bird radar. We designed a detailed process to remove tracks or echoes from non-bird targets, ensuring the effectiveness of bird observations. The field experiments validated the quantification method, showing that the average radar cross section of birds in Jinan was 19.09 dBscm (i.e., 81.19 cm2; 95% confidence interval, CI: 18.92\u201319.27 dBscm) for the S-band weather radar, with an R2 of 0.79. In addition, through the correlation analysis, we found that the ground terrain may affect the distribution pattern of aerial bird density.<\/jats:p>","DOI":"10.3390\/rs15194809","type":"journal-article","created":{"date-parts":[[2023,10,3]],"date-time":"2023-10-03T07:28:29Z","timestamp":1696318109000},"page":"4809","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Quantification of Migration Birds Based on Polarimetric Weather Radar"],"prefix":"10.3390","volume":"15","author":[{"given":"Rui","family":"Wang","sequence":"first","affiliation":[{"name":"The Key Laboratory of Electronic and Information Technology in Satellite Navigation, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"},{"name":"The Advanced Technology Research Institute, Beijing Institute of Technology, Jinan 250300, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huafeng","family":"Mao","sequence":"additional","affiliation":[{"name":"The Key Laboratory of Electronic and Information Technology in Satellite Navigation, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7208-9046","authenticated-orcid":false,"given":"Kai","family":"Cui","sequence":"additional","affiliation":[{"name":"The Advanced Technology Research Institute, Beijing Institute of Technology, Jinan 250300, China"},{"name":"The School of Computer Sciences, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhuoran","family":"Sun","sequence":"additional","affiliation":[{"name":"The Key Laboratory of Electronic and Information Technology in Satellite Navigation, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7582-5291","authenticated-orcid":false,"given":"Cheng","family":"Hu","sequence":"additional","affiliation":[{"name":"The Key Laboratory of Electronic and Information Technology in Satellite Navigation, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"},{"name":"The Advanced Technology Research Institute, Beijing Institute of Technology, Jinan 250300, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dongli","family":"Wu","sequence":"additional","affiliation":[{"name":"The Meteorological Observation Center of China Meteorological Administration, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1115","DOI":"10.1126\/science.aat7526","article-title":"A continental system for forecasting bird migration","volume":"361","author":"Horton","year":"2018","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1584","DOI":"10.1126\/science.aah4379","article-title":"Mass seasonal bioflows of high-flying insect migrants","volume":"354","author":"Hu","year":"2016","journal-title":"Science"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/S0168-1699(02)00013-3","article-title":"Development of vertical-looking radar technology for monitoring insect migration","volume":"35","author":"Chapman","year":"2002","journal-title":"Comput. 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