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Title: High-Resolution Spatial Distribution of Bird Movements Estimated from a Weather Radar Network
Weather radars provide detailed information on aerial movements of organisms. However, interpreting fine-scale radar imagery remains challenging because of changes in aerial sampling altitude with distance from the radar. Fine-scale radar imagery has primarily been used to assess mass exodus at sunset to study stopover habitat associations. Here, we present a method that enables a more intuitive integration of information across elevation scans projected in a two-dimensional spatial image of fine-scale radar reflectivity. We applied this method on nights of intense bird migration to demonstrate how the spatial distribution of migrants can be explored at finer spatial scales and across multiple radars during the higher flying en-route phase of migration. The resulting reflectivity maps enable explorative analysis of factors influencing their regional and fine-scale distribution. We illustrate the method’s application by generating time-series of composites of up to 20 radars, achieving a nearly complete spatial coverage of a large part of Northwest Europe. These visualizations are highly useful in interpreting regional-scale migration patterns and provide detailed information on bird movements in the landscape and aerial environment.  more » « less
Award ID(s):
1661259 1661329
NSF-PAR ID:
10162415
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Remote Sensing
Volume:
12
Issue:
4
ISSN:
2072-4292
Page Range / eLocation ID:
635
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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