was published in August, 2016 [62], it is realistic that within two years after the end of IOC, Stages 1 through 3 will be complete, and work toward Stage 4 will be well underway. The SMAP Cal/Val plan [46] describes five types of resources that will be utilized as sources of calibration/validation data. These types of data are listed in Table 9, which describes their perceived role and issues that are currently being addressed by the SMAP team. The NSPIRES DCL entry in the table refers to a Dear Colleague Letter request for information that was released by NASA to the science community to solicit members of the SMAP cal/val team and core validation and other validation sites globally. A NASA panel in consultation with the SMAP team selected ~27 investigator sites or supported instrument networks in Summer, 2011. Since then several new sites have been added. Table 9. Overview of the SMAP Cal/Val Methodologies Methodology Role Issues Actions Core Validation Accurate estimates of Calibration Testbed In Situ Sites products at matching Up-scaling Scaling methods scales for a limited set of Limited number NSPIRES DCL conditions Sparse One point in the grid cell Calibration Testbed In Situ Networks for a wide range of Up-scaling Scaling methods conditions Limited number NSPIRES DCL Satellite Products Estimates over a very wide Validation Validation range of conditions at Comparability Studies matching scales Continuity CDF Matching Model Products Estimates over a very wide Validation Validation range of conditions at Comparability Studies matching scales Field Detailed estimates for a Resources Simulators Experiments very limited set of Schedule Conflicts Partnerships conditions The baseline validation for the L2_SM_P soil moisture will be a comparison of retrievals at 36 km with ground-based observations that have been verified as providing a spatial average of soil moisture at the same scale, referred to as core validation sites (CVS) in the SMAP Calibration / Validation Plan. This matches up closely with the Stage 1 validation described in Table 8. Data from core validation sites will be supplemented by field experiments. In order to achieve Stage 2 validation and include a wider range of conditions as well as a synoptic/global assessment, some combination of data from sparse networks, other satellite products, and model-based estimates must be utilized. Each of these data types has caveats associated with it that are described in Table 9. The following
was published in August, 2016 [62], it is realistic that within two years after the end of IOC, Stages 1 through 3 will be complete, and work toward Stage 4 will be well underway. The SMAP Cal/Val plan [46] describes five types of resources that will be utilized as sources of calibration/validation data. These types of data are listed in Table 9, which describes their perceived role and issues that are currently being addressed by the SMAP team. The NSPIRES DCL entry in the table refers to a Dear Colleague Letter request for information that was released by NASA to the science community to solicit members of the SMAP cal/val team and core validation and other validation sites globally. A NASA panel in consultation with the SMAP team selected ~27 investigator sites or supported instrument networks in Summer, 2011. Since then several new sites have been added. Table 9. Overview of the SMAP Cal/Val Methodologies Methodology Role Issues Actions Core Validation Sites Accurate estimates of products at matching scales for a limited set of conditions Calibration Up-scaling Limited number In Situ Testbed Scaling methods NSPIRES DCL Sparse Networks One point in the grid cell for a wide range of conditions Calibration Up-scaling Limited number In Situ Testbed Scaling methods NSPIRES DCL Satellite Products Estimates over a very wide range of conditions at matching scales Validation Comparability Continuity Validation Studies CDF Matching Model Products Estimates over a very wide range of conditions at matching scales Validation Comparability Validation Studies Field Experiments Detailed estimates for a very limited set of conditions Resources Schedule Conflicts Simulators Partnerships The baseline validation for the L2_SM_P soil moisture will be a comparison of retrievals at 36 km with ground-based observations that have been verified as providing a spatial average of soil moisture at the same scale, referred to as core validation sites (CVS) in the SMAP Calibration / Validation Plan. This matches up closely with the Stage 1 validation described in Table 8. Data from core validation sites will be supplemented by field experiments. In order to achieve Stage 2 validation and include a wider range of conditions as well as a synoptic/global assessment, some combination of data from sparse networks, other satellite products, and model-based estimates must be utilized. Each of these data types has caveats associated with it that are described in Table 9. The following