Estimating root zone soil moisture using near-surface observations from SMOS
Satellite-derived soil moisture provides more spatially and temporally extensive data than in situ observations. However, satellites can only measure water in the top few centimeters of the soil. Root zone soil moisture is more important, particularly in vegetated regions. Therefore estimates of roo...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2014-01-01
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| Series: | Hydrology and Earth System Sciences |
| Online Access: | http://www.hydrol-earth-syst-sci.net/18/139/2014/hess-18-139-2014.pdf |
| _version_ | 1811224661270200320 |
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| author | T. W. Ford E. Harris S. M. Quiring |
| author_facet | T. W. Ford E. Harris S. M. Quiring |
| author_sort | T. W. Ford |
| collection | DOAJ |
| description | Satellite-derived soil moisture provides more spatially and temporally
extensive data than in situ observations. However, satellites can only measure
water in the top few centimeters of the soil. Root zone soil moisture is
more important, particularly in vegetated regions. Therefore estimates of
root zone soil moisture must be inferred from near-surface soil moisture
retrievals. The accuracy of this inference is contingent on the relationship
between soil moisture in the near-surface and the soil moisture at greater
depths. This study uses cross correlation analysis to quantify the
association between near-surface and root zone soil moisture using in situ data
from the United States Great Plains. Our analysis demonstrates that there is
generally a strong relationship between near-surface (5–10 cm) and root
zone (25–60 cm) soil moisture. An exponential decay filter is used to
estimate root zone soil moisture using near-surface soil moisture derived
from the Soil Moisture and Ocean Salinity (SMOS) satellite. Root zone soil
moisture derived from SMOS surface retrievals is compared to in situ soil moisture
observations in the United States Great Plains. The SMOS-based root zone
soil moisture had a mean <i>R</i><sup>2</sup> of 0.57 and a mean Nash–Sutcliffe score of
0.61 based on 33 stations in Oklahoma. In Nebraska, the SMOS-based root zone
soil moisture had a mean <i>R</i><sup>2</sup> of 0.24 and a mean Nash–Sutcliffe score of
0.22 based on 22 stations. Although the performance of the exponential
filter method varies over space and time, we conclude that it is a useful
approach for estimating root zone soil moisture from SMOS surface
retrievals. |
| first_indexed | 2024-04-12T08:52:50Z |
| format | Article |
| id | doaj.art-6e871d3157074b51a160ebff4dab4b62 |
| institution | Directory Open Access Journal |
| issn | 1027-5606 1607-7938 |
| language | English |
| last_indexed | 2024-04-12T08:52:50Z |
| publishDate | 2014-01-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Hydrology and Earth System Sciences |
| spelling | doaj.art-6e871d3157074b51a160ebff4dab4b622022-12-22T03:39:31ZengCopernicus PublicationsHydrology and Earth System Sciences1027-56061607-79382014-01-0118113915410.5194/hess-18-139-2014Estimating root zone soil moisture using near-surface observations from SMOST. W. Ford0E. Harris1S. M. Quiring2Department of Geography, Texas A&M University, College Station, Texas, USADepartment of Geography, Texas A&M University, College Station, Texas, USADepartment of Geography, Texas A&M University, College Station, Texas, USASatellite-derived soil moisture provides more spatially and temporally extensive data than in situ observations. However, satellites can only measure water in the top few centimeters of the soil. Root zone soil moisture is more important, particularly in vegetated regions. Therefore estimates of root zone soil moisture must be inferred from near-surface soil moisture retrievals. The accuracy of this inference is contingent on the relationship between soil moisture in the near-surface and the soil moisture at greater depths. This study uses cross correlation analysis to quantify the association between near-surface and root zone soil moisture using in situ data from the United States Great Plains. Our analysis demonstrates that there is generally a strong relationship between near-surface (5–10 cm) and root zone (25–60 cm) soil moisture. An exponential decay filter is used to estimate root zone soil moisture using near-surface soil moisture derived from the Soil Moisture and Ocean Salinity (SMOS) satellite. Root zone soil moisture derived from SMOS surface retrievals is compared to in situ soil moisture observations in the United States Great Plains. The SMOS-based root zone soil moisture had a mean <i>R</i><sup>2</sup> of 0.57 and a mean Nash–Sutcliffe score of 0.61 based on 33 stations in Oklahoma. In Nebraska, the SMOS-based root zone soil moisture had a mean <i>R</i><sup>2</sup> of 0.24 and a mean Nash–Sutcliffe score of 0.22 based on 22 stations. Although the performance of the exponential filter method varies over space and time, we conclude that it is a useful approach for estimating root zone soil moisture from SMOS surface retrievals.http://www.hydrol-earth-syst-sci.net/18/139/2014/hess-18-139-2014.pdf |
| spellingShingle | T. W. Ford E. Harris S. M. Quiring Estimating root zone soil moisture using near-surface observations from SMOS Hydrology and Earth System Sciences |
| title | Estimating root zone soil moisture using near-surface observations from SMOS |
| title_full | Estimating root zone soil moisture using near-surface observations from SMOS |
| title_fullStr | Estimating root zone soil moisture using near-surface observations from SMOS |
| title_full_unstemmed | Estimating root zone soil moisture using near-surface observations from SMOS |
| title_short | Estimating root zone soil moisture using near-surface observations from SMOS |
| title_sort | estimating root zone soil moisture using near surface observations from smos |
| url | http://www.hydrol-earth-syst-sci.net/18/139/2014/hess-18-139-2014.pdf |
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