Evaluation of near-surface soil moisture data from an AAFC monitoring network in Manitoba, Canada: Implications for L-band satellite validation

摘要: Summary This paper examines near-surface soil moisture data (top ∼6 cm) from an Agriculture and Agri-food Canada (AAFC) monitoring network in southern Manitoba, Canada, over the 2012 2013 growing seasons. is intended for use (in part) as a core validation site Soil Moisture Active Passive (SMAP) mission. The currently consists of 9 stations sited within agricultural fields. Each station uses triplicate configuration horizontally installed Hydra Probe sensors at (∼5 cm) to root-zone depths, addition permanently vertical surface (0–5.7 cm). domain was studied intensively 6.5 week SMAPVEX12 ground campaign June/July 2012, providing coincident datasets assess up-scaling domain. Results demonstrate that statistical differences exist between network-level horizontal ( θ 3.5 – 6.5cm ) 0 5.7cm Probes 2012–13. Bootstrap resampling shows mean difference 0.018 m 3  m −3 (at 99% confidence) observed measurement depths exhibit dry bias). Individual analysis largest depth occur sites with higher clay content, whereas located sandy soils negligible differences. Up-scaling comparisons AAFC field-sampled dense temporary it representative 0.04 m RMSE. suggests suitable coarse resolution L-band microwave validation. Comparison Ocean Salinity (SMOS) Level 2 product up-scaled 2012–13 superior temporal correlation found dataset. RMSEs SMOS approximately . These results suggest sensor should be considered when conducting satellite