Appraisal of SMAP Operational Soil Moisture Product from a Global Perspective
Abstract
:1. Introduction
2. Materials and Methods
2.1. In Situ Measurements
2.2. Satellite Data Description
2.2.1. SMAP L4 Soil Moisture Product
2.2.2. NASA Global Precipitation Measurement Integrated Multi-SatellitE Retrievals for GPM (IMERG)
2.3. Performance Statistics
3. Results
3.1. North America
3.1.1. Performance Comparison at Different Stations
3.1.2. Temporal Consistency
3.2. Europe
3.2.1. Performance Comparison at Different Stations
3.2.2. Temporal Consistency
3.3. Asia
3.3.1. Performance Comparison at Different Stations
3.3.2. Temporal consistency
3.4. Australia
3.4.1. Performance comparison at different stations
3.4.2. Temporal Consistency
4. Discussion
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Location | ISMN Network | Sensor | Soil Depth | Parameters |
---|---|---|---|---|
North America (USA) | USCRN | Stevens Water Inc. Stevens Hydra Probe II | 0–0.05 m 0.05–0.1 m 0.1–0.2 m 0.2–0.5 m 0.5–1.0 m | Soil moisture, soil temperature, precipitation, air temperature, surface temperature. |
Europe (Dumbraveni, Romania) | RSMN | Decagon Device 5TM | 0–0.05 m | Soil moisture, soil temperature, precipitation, air temperature. |
Europe (Feldbach, Austria) | WEGENERNET | Stevens Water Inc. Stevens Hydra Probe II | 0.0–0.2 m | Soil moisture, soil temperature, precipitation, air temperature. |
Europe (El Coto, Spain) | REMEDHUS | Stevens Water Inc. Stevens Hydra Probe II | 0–0.05 m | Soil moisture, soil temperature. |
Asia (India) | Local Network | Stevens Water Inc. Stevens Hydra Probe II | 0–0.05 m | Soil moisture, soil temperature, precipitation, air temperature. |
Australia (Yanco) | Oz Net | Stevens Water Inc. Stevens Hydra Probe II | 0–0.05 m 0–0.3 m | Soil moisture, soil temperature, precipitation, air temperature. |
Description | Equations |
---|---|
Square of Correlation (R2) | |
Root Mean Square Error (RMSE) | |
Degree of Agreement (d) | |
Percentage bias (PBIAS) |
Statistical Test | Fallbrook | Tucson | Panther Junction | Socorro |
---|---|---|---|---|
Square of correlation (R2) | 0.66 | 0.51 | 0.43 | 0.11 |
Root mean square error (RMSE) (m3/m3) | 0.08 | 0.04 | 0.03 | 0.05 |
Degree of agreement (d) | 0.46 | 0.65 | 0.74 | 0.55 |
PBIAS | −57.9 | 120.60 | 26.10 | 56.80 |
Statistical Test | Dumbraveni | Feldbach Region | El Coto |
---|---|---|---|
Square of correlation (R2) | 0.24 | 0.14 | 0.55 |
Root mean square error (RMSE) (m3/m3) | 0.18 | 0.09 | 0.16 |
Degree of agreement (d) | 0.41 | 0.41 | 0.48 |
PBIAS | −59.30 | 23.0 | −78.50 |
Statistical Test | Varanasi | Hoshangabad | Anand |
---|---|---|---|
Square of correlation (R2) | 0.72 | 0.71 | 0.67 |
Root mean square error (RMSE) (m3/m3) | 0.07 | 0.14 | 0.07 |
Degree of agreement (d) | 0.88 | 0.76 | 0.86 |
PBIAS | −18.60 | −29.60 | 22.90 |
Statistical Test | Cox | Samarra | Uri Park | Yanco |
---|---|---|---|---|
Square of correlation (R2) | 0.24 | 0.19 | 0.48 | 0.29 |
Root mean square error (RMSE) (m3/m3) | 0.06 | 0.10 | 0.08 | 0.08 |
Degree of agreement (d) | 0.53 | 0.59 | 0.49 | 0.57 |
PBIAS | −34.20 | 28.90 | 93.30 | −31.60 |
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Suman, S.; Srivastava, P.K.; Petropoulos, G.P.; Pandey, D.K.; O’Neill, P.E. Appraisal of SMAP Operational Soil Moisture Product from a Global Perspective. Remote Sens. 2020, 12, 1977. https://doi.org/10.3390/rs12121977
Suman S, Srivastava PK, Petropoulos GP, Pandey DK, O’Neill PE. Appraisal of SMAP Operational Soil Moisture Product from a Global Perspective. Remote Sensing. 2020; 12(12):1977. https://doi.org/10.3390/rs12121977
Chicago/Turabian StyleSuman, Swati, Prashant K. Srivastava, George P. Petropoulos, Dharmendra K. Pandey, and Peggy E. O’Neill. 2020. "Appraisal of SMAP Operational Soil Moisture Product from a Global Perspective" Remote Sensing 12, no. 12: 1977. https://doi.org/10.3390/rs12121977