Can GNSS Reflectometry Detect Precipitation Over Oceans?
- For the first time, a rain signature in Global Navigation Satellite System Reflectometry (GNSS-R) observations is demonstrated. Based on the argument that the forward quasi-specular scattering relies upon surface gravity waves with lengths larger than several wavelengths of the reflected signal, a commonly made conclusion is that the scatterometric GNSS-R measurements are not sensitive to the surface small-scale roughness generated by raindrops impinging on the ocean surface. On the contrary, this study presents an evidence that the bistatic radar cross section sigma(0) derived from TechDemoSat-1 data is reduced due to rain at weak winds, lower than approximate to 6 m/s. The decrease is as large as approximate to 0.7 dB at the wind speed of 3 m/s due to a precipitation of 0-2 mm/hr. The simulations based on the recently published scattering theory provide a plausible explanation for this phenomenon which potentially enables the GNSS-R technique to detect precipitation over oceans at low winds.
Author details: | Milad AsgarimehrORCiD, Valery Zavorotny, Jens WickertORCiD, Sebastian ReichORCiDGND |
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DOI: | https://doi.org/10.1029/2018GL079708 |
ISSN: | 0094-8276 |
ISSN: | 1944-8007 |
Title of parent work (English): | Geophysical research letters |
Publisher: | American Geophysical Union |
Place of publishing: | Washington |
Publication type: | Article |
Language: | English |
Date of first publication: | 2018/11/06 |
Publication year: | 2018 |
Release date: | 2021/06/29 |
Tag: | GNSS Reflectometry; TDS-1; electromagnetic scattering; ocean surface; rain detection; rain splash |
Volume: | 45 |
Issue: | 22 |
Number of pages: | 8 |
First page: | 12585 |
Last Page: | 12592 |
Funding institution: | Geo.X, the Research Network for Geosciences in Berlin and Potsdam |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Geowissenschaften |
DDC classification: | 5 Naturwissenschaften und Mathematik / 55 Geowissenschaften, Geologie / 550 Geowissenschaften |
Peer review: | Referiert |
Publishing method: | Open Access / Hybrid Open-Access |
License (German): | CC-BY-NC-ND - Namensnennung, nicht kommerziell, keine Bearbeitungen 4.0 International |