@article{fdi:010071431,
  title = {{D}isaggregation of {SMOS} soil moisture to 100 m resolution using {MODIS} optical/thermal and sentinel-1 radar data : evaluation over a bare soil site in {M}orocco},
  author = {{E}weys, {O}. {A}. and {E}scorihuela, {M}. {J}. and {V}illar, {J}. {M}. and {E}r-{R}aki, {S}. and {A}mazirh, {A}. and {O}livera, {L}. and {J}arlan, {L}ionel and {K}habba, {S}. and {M}erlin, {O}livier},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he 40 km resolution {SMOS} ({S}oil {M}oisture and {O}cean {S}alinity) soil moisture, previously disaggregated at a 1 km resolution using the {DISPATCH} ({DIS}aggregation based on {P}hysical {A}nd {T}heoretical scale {CH}ange) method based on {MODIS} optical/thermal data, is further disaggregated to 100 m resolution using {S}entinel-1 backscattering coefficient (sigma degrees). {F}or this purpose, three distinct radar-based disaggregation methods are tested by linking the spatio-temporal variability of sigma degrees and soil moisture data at the 1 km and 100 m resolution. {T}he three methods are: (1) the weight method, which estimates soil moisture at 100 m resolution at a certain time as a function of sigma degrees ratio (100 m to 1 km resolution) and the 1 km {DISPATCH} products of the same time; (2) the regression method which estimates soil moisture as a function of sigma degrees where the regression parameters (e.g., intercept and slope) vary in space and time; and (3) the {C}umulative {D}istribution {F}unction ({CDF}) method, which estimates 100 m resolution soil moisture from the cumulative probability of 100 m resolution backscatter and the maximum to minimum 1 km resolution ({DISPATCH}) soil moisture difference. {I}n each case, disaggregation results are evaluated against in situ measurements collected between 1 {J}anuary 2016 and 11 {O}ctober 2016 over a bare soil site in central {M}orocco. {T}he determination coefficient ({R}-2) between 1 km resolution {DISPATCH} and localized in situ soil moisture is 0.31. {T}he regression and {CDF} methods have marginal effect on improving the {DISPATCH} accuracy at the station scale with a {R}-2 between remotely sensed and in situ soil moisture of 0.29 and 0.34, respectively. {B}y contrast, the weight method significantly improves the correlation between remotely sensed and in situ soil moisture with a {R}-2 of 0.52. {L}ikewise, the soil moisture estimates show low root mean square difference with in situ measurements ({RMSD} = 0.032 m(3) m(-3)).},
  keywords = {soil moisture and ocean salinity satellite ({SMOS}) ; {DISPATCH} ; radar ; {S}entinel-1 ; disaggregation ; soil moisture ; {MAROC}},
  booktitle = {},
  journal = {{R}emote {S}ensing},
  volume = {9},
  numero = {11},
  pages = {art. 1155 [20 p.]},
  ISSN = {2072-4292},
  year = {2017},
  DOI = {10.3390/rs9111155},
  URL = {https://www.documentation.ird.fr/hor/fdi:010071431},
}