Estimating Vegetation Optical Depth With Mobile GNSS Transmissiometry in Temperate Forests During SMAPVEX22

IF 4.7 2区地球科学 Q1 ENGINEERING, ELECTRICAL & ELECTRONIC

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Pub Date : 2025-02-13 DOI:10.1109/JSTARS.2025.3541182

Abesh Ghosh;Md Mehedi Farhad;Mohammad Ehsanul Hoque;Dylan Ray Boyd;Laura Bourgeau-Chavez;Michael H. Cosh;Andreas Colliander;Mehmet Kurum

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引用次数: 0

Abstract

This study investigates the potential of mobile global navigation satellite system (GNSS) transmissometry (GNSS-T) measurements for estimating vegetation optical depth (VOD) in temperate forests, focusing on the Soil Moisture Active Passive (SMAP) validation experiment in 2022 (SMAPVEX22). Our methodology employed a dual-GNSS receiver setup, with one receiver positioned in open terrain to serve as a reference for direct signals, and another deployed on a mobile unit (helmet-based or robotic system) to spatially sample vegetation across expansive forested regions during SMAPVEX22. We assessed the stability of direct signal measurements over multiple days, demonstrating the reliability of the GNSS-T measurements. We reported the VOD measurement results for various sites across different forest regions during intensive observation periods and evaluated their correlation with respect to in situ vegetation parameters such as basal area, biomass, canopy height, and diameter breast height, finding a strong correlation with the basal area (

$R^{2}=0.73$

). In addition, with a predictive regression model, we demonstrated a strong dependence of the measured VOD on combination of such forest parameters. An evaluation of the VOD values at different satellite elevation angles highlighted an increasing trend in VOD with the incidence angle. The results showed the potential utility of mobile GNSS-T for generating large-scale VOD observations. Although spatially averaged VOD maps might not be directly comparable to spaceborne observations, combining mobile GNSS-T data with other sensors such as LiDAR can provide a reliable reference for airborne or spaceborne VOD estimates.

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来源期刊

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing 地学-成像科学与照相技术

CiteScore

9.30

自引率

10.90%

发文量

563

审稿时长

4.7 months

期刊介绍： The IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing addresses the growing field of applications in Earth observations and remote sensing, and also provides a venue for the rapidly expanding special issues that are being sponsored by the IEEE Geosciences and Remote Sensing Society. The journal draws upon the experience of the highly successful “IEEE Transactions on Geoscience and Remote Sensing” and provide a complementary medium for the wide range of topics in applied earth observations. The ‘Applications’ areas encompasses the societal benefit areas of the Global Earth Observations Systems of Systems (GEOSS) program. Through deliberations over two years, ministers from 50 countries agreed to identify nine areas where Earth observation could positively impact the quality of life and health of their respective countries. Some of these are areas not traditionally addressed in the IEEE context. These include biodiversity, health and climate. Yet it is the skill sets of IEEE members, in areas such as observations, communications, computers, signal processing, standards and ocean engineering, that form the technical underpinnings of GEOSS. Thus, the Journal attracts a broad range of interests that serves both present members in new ways and expands the IEEE visibility into new areas.