On the synergy of airborne GNSS-R and landsat 8 for soil moisture estimation

While the synergy between thermal, optical, and passive microwave observations is well known for the estimation of soil moisture and vegetation parameters, the use of remote sensing sources based on the Global Navigation Satellite Systems (GNSS) remains unexplored. During an airborne campaign perfor...

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Detalles Bibliográficos
Autores: Sanchez, Nilda, Alonso Arroyo, Alberto, Martinez Fernandez, Jose, Piles Guillem, Maria|||0000-0002-1169-3098, Gonzalez Zamora, Angel, Camps Carmona, Adriano José|||0000-0002-9514-4992, Vall-Llossera Ferran, Mercedes Magdalena|||0000-0003-1357-7098
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/79572
Acceso en línea:https://hdl.handle.net/2117/79572
https://dx.doi.org/10.3390/rs70809954
Access Level:acceso abierto
Palabra clave:Global Positioning System
Soil moisture--Measurement
Difference water index
High-resolution
Vegetation
SMOS
Retrieval
Imagery
NDWI
GPS
GNSS (Sistema de navegació)
Sòls -- Humitat -- Mesurament
Àrees temàtiques de la UPC::Enginyeria de la telecomunicació
Descripción
Sumario:While the synergy between thermal, optical, and passive microwave observations is well known for the estimation of soil moisture and vegetation parameters, the use of remote sensing sources based on the Global Navigation Satellite Systems (GNSS) remains unexplored. During an airborne campaign performed in August 2014, over an agricultural area in the Duero basin (Spain), an innovative sensor developed by the Universitat Politecnica de Catalunya-Barcelona Tech based on GNSS Reflectometry (GNSS-R) was tested for soil moisture estimation. The objective was to evaluate the combined use of GNSS-R observations with a time-collocated Landsat 8 image for soil moisture retrieval under semi-arid climate conditions. As a ground reference dataset, an intensive field campaign was carried out. The Light Airborne Reflectometer for GNSS-R Observations (LARGO) observations, together with optical, infrared, and thermal bands from Landsat 8, were linked through a semi-empirical model to field soil moisture. Different combinations of vegetation and water indices with LARGO subsets were tested and compared to the in situ measurements. Results showed that the joint use of GNSS-R reflectivity, water/vegetation indices and thermal maps from Landsat 8 not only allows capturing soil moisture spatial gradients under very dry soil conditions, but also holds great promise for accurate soil moisture estimation (correlation coefficients greater than 0.5 were obtained from comparison with in situ data).