TY - JOUR
T1 - Toward P-Band Passive Microwave Sensing of Soil Moisture
AU - Ye, Nan
AU - Walker, Jeffrey P.
AU - Yeo, In-Young
AU - Jackson, Thomas J.
AU - Kerr, Yann
AU - Kim, Edward
AU - McGrath, Andrew
AU - Popstefanija, Ivan
AU - Goodberlet, Mark
AU - Hills, James
PY - 2021/3
Y1 - 2021/3
N2 - Currently, near-surface soil moisture at a global scale is being provided using National Aeronautics and Space Administration's (NASA's) Soil Moisture Active Passive (SMAP) and European Space Agency's (ESA's) Soil Moisture and Ocean Salinity (SMOS) satellites, both of which utilize L-band (1.4 GHz; 21 cm wavelength) passive microwave remote sensing techniques. However, a fundamental limitation of this technology is that the water content can only be measured for approximately the top 5-cm layer of soil moisture, and only over low-to-moderate vegetation covered areas in order to meet the 0.04 text{m}{3}/text{m}{3} target accuracy, limiting its applicability. Consequently, a longer wavelength radiometer is being explored as a potential solution for measuring soil moisture in a deeper surface layer of soil and under denser vegetation. It is expected that P-band (wavelength of 40 cm and frequency of 750 MHz) could potentially provide soil moisture information for the top sim 10 -cm layer of soil, being one-tenth to one-quarter of the wavelength. In addition, P-band is expected to have higher soil moisture retrieval accuracy due to its reduced sensitivity to vegetation water content and surface roughness. To demonstrate the potential of P-band passive microwave soil moisture remote sensing, a short-term airborne field experiment was conducted over a center pivot irrigated farm at Cressy in Tasmania, Australia, in January 2017. First results showing a comparison of airborne P-band brightness temperature observations against airborne L-band brightness temperature observations and ground soil moisture measurements are presented. The P-band brightness temperature was found to have a similar but stronger response to soil moisture compared to L-band.
AB - Currently, near-surface soil moisture at a global scale is being provided using National Aeronautics and Space Administration's (NASA's) Soil Moisture Active Passive (SMAP) and European Space Agency's (ESA's) Soil Moisture and Ocean Salinity (SMOS) satellites, both of which utilize L-band (1.4 GHz; 21 cm wavelength) passive microwave remote sensing techniques. However, a fundamental limitation of this technology is that the water content can only be measured for approximately the top 5-cm layer of soil moisture, and only over low-to-moderate vegetation covered areas in order to meet the 0.04 text{m}{3}/text{m}{3} target accuracy, limiting its applicability. Consequently, a longer wavelength radiometer is being explored as a potential solution for measuring soil moisture in a deeper surface layer of soil and under denser vegetation. It is expected that P-band (wavelength of 40 cm and frequency of 750 MHz) could potentially provide soil moisture information for the top sim 10 -cm layer of soil, being one-tenth to one-quarter of the wavelength. In addition, P-band is expected to have higher soil moisture retrieval accuracy due to its reduced sensitivity to vegetation water content and surface roughness. To demonstrate the potential of P-band passive microwave soil moisture remote sensing, a short-term airborne field experiment was conducted over a center pivot irrigated farm at Cressy in Tasmania, Australia, in January 2017. First results showing a comparison of airborne P-band brightness temperature observations against airborne L-band brightness temperature observations and ground soil moisture measurements are presented. The P-band brightness temperature was found to have a similar but stronger response to soil moisture compared to L-band.
KW - Airborne field experiments
KW - brightness temperature
KW - L-band
KW - P-band
KW - soil moisture
UR - http://www.scopus.com/inward/record.url?scp=85099059369&partnerID=8YFLogxK
UR - http://purl.org/au-research/grants/ARC/DP170102373
UR - http://purl.org/au-research/grants/ARC/LE0453434
UR - http://purl.org/au-research/grants/ARC/LE150100047
U2 - 10.1109/LGRS.2020.2976204
DO - 10.1109/LGRS.2020.2976204
M3 - Article
AN - SCOPUS:85099059369
VL - 18
SP - 504
EP - 508
JO - Geoscience and Remote Sensing Letters, IEEE
JF - Geoscience and Remote Sensing Letters, IEEE
SN - 1545-598X
IS - 3
ER -