0000000000118074

AUTHOR

Chandra Holifield Collins

showing 3 related works from this author

Assessment of the SMAP Level-4 Surface and Root-Zone Soil Moisture Product Using In Situ Measurements

2017

International audience; The Soil Moisture Active Passive (SMAP) mission Level-4 Surface and Root-Zone Soil Moisture (L4_SM) data product is generated by assimilating SMAP L-band brightness temperature observations into the NASA Catchment land surface model. The L4_SM product is available from 31 March 2015 to present (within 3 days from real time) and provides 3-hourly, global, 9-km resolution estimates of surface (0-5 cm) and root-zone (0-100 cm) soil moisture and land surface conditions. This study presents an overview of the L4_SM algorithm, validation approach, and product assessment versus in situ measurements. Core validation sites provide spatially averaged surface (root zone) soil m…

Atmospheric Science010504 meteorology & atmospheric sciences0208 environmental biotechnologyDrainage basin[SDU.STU]Sciences of the Universe [physics]/Earth SciencesSoil science02 engineering and technologyLand cover01 natural sciencesStandard deviationITC-HYBRIDData assimilationSoil temperatureWater content0105 earth and related environmental sciencesgeographygeography.geographical_feature_category020801 environmental engineeringSatellite observations[SDU]Sciences of the Universe [physics]Brightness temperatureITC-ISI-JOURNAL-ARTICLEData assimilationDNS root zoneEnvironmental scienceSoil moistureLand surface modelScale (map)Kalman filtersJournal of hydrometeorology
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The SMAP mission combined active-passive soil moisture product at 9 km and 3 km spatial resolutions

2018

Abstract The NASA Soil Moisture Active Passive (SMAP) mission was launched on January 31st, 2015. The spacecraft was to provide high-resolution (3 km and 9 km) global soil moisture estimates at regular intervals by combining for the first time L-band radiometer and radar observations. On July 7th, 2015, a component of the SMAP radar failed and the radar ceased operation. However, before this occurred the mission was able to collect and process ~2.5 months of the SMAP high-resolution active-passive soil moisture data (L2SMAP) that coincided with the Northern Hemisphere's vegetation green-up and crop growth season. In this study, we evaluate the SMAP high-resolution soil moisture product deri…

National Snow and Ice Data CenterRadiometer010504 meteorology & atmospheric sciences0211 other engineering and technologiesNorthern HemisphereSoil ScienceGeology02 engineering and technologyVegetation01 natural sciencesActive passivelaw.inventionlawEnvironmental scienceProduct (category theory)Computers in Earth SciencesRadarWater content021101 geological & geomatics engineering0105 earth and related environmental sciencesRemote sensingRemote Sensing of Environment
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The SMAP and Copernicus Sentinel 1A/B microwave active-passive high resolution surface soil moisture product

2019

Abstract Soil Moisture Active Passive (SMAP) mission of NASA was launched in January 2015. Currently, SMAP has an L-band radiometer and a defunct L-band radar with a rotating 6-m mesh reflector antenna. On July 7th, 2015, the SMAP radar malfunctioned and became inoperable. Consequently, the production of high-resolution active-passive soil moisture product got hampered, and only ~2.5 months (April 15th, 2015 to July 7th, 2015) of data remain available. Therefore, during the SMAP post-radar phase, many ways were examined to restart the high-resolution soil moisture product generation of the SMAP mission. One of the feasible approaches was to substitute the SMAP radar with other available SAR…

National Snow and Ice Data Center010504 meteorology & atmospheric sciences0208 environmental biotechnologySoil Science02 engineering and technology01 natural scienceslaw.inventionlawCalibrationComputers in Earth SciencesRadarImage resolution0105 earth and related environmental sciencesRemote sensingRadiometeractive-passiveGeologySMAPradiometer020801 environmental engineeringBrightness temperatureTemporal resolutionEnvironmental sciencesoil moistureMicrowaveSARRemote Sensing of Environment
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