Validation of SMAP L2 passive-only soil moisture products using upscaled in situ measurements collected in Twente, the Netherlands
نویسندگان
چکیده
Abstract. The Twente region in the east of Netherlands has a network with 20 soil monitoring stations that been utilized for validation Soil Moisture Active/Passive (SMAP) passive-only moisture products. Over period from April 2015 until December 2018, seven covered by SMAP reference pixels have fairly complete data records. Spatially distributed simulations Dutch National Hydrological Model development upscaling functions to translate spatial mean point measurements domain pixels. native and upscaled means computed using situ adopted as references assess performance (i) Single Channel Algorithm at Horizontal Polarization (SCA-H), (ii) Vertical (SCA-V), (iii) Dual (DCA) estimates. In case it was found SCA-V observations collected afternoon had best agreement mean, leading an unbiased root squared error (uRMSE) 0.059 m3 m−3, whereas primarily larger biases were found. These levels are than mission's target accuracy 0.04 which can be attributed large over- under-estimation errors (>0.08 m−3), particular end dry spells during freezing, respectively. strong vertical dielectric gradients associated rapid freezing wetting cause disparity depth characterized leads mismatches. Once filtered frozen conditions antecedent rainfall, uRMSE improves 0.043 m−3.
منابع مشابه
Soil Moisture Active Passive (SMAP) Algorithm Theoretical Basis Document SMAP L2 & L3 Radar Soil Moisture (Active) Data Products
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ژورنال
عنوان ژورنال: Hydrology and Earth System Sciences
سال: 2021
ISSN: ['1607-7938', '1027-5606']
DOI: https://doi.org/10.5194/hess-25-473-2021