@article{PAR00011907,
  title = {{G}lobal-scale evaluation of two satellite-based passive microwave soil moisture datasets ({SMOS} and {AMSR}-{E}) with respect to {L}and {D}ata {A}ssimilation {S}ystem estimates},
  author = {{A}l-{Y}aari, {A}. and {W}igneron, {J}.{P}. and {D}ucharne, {A}. and {K}err, {Y}ann and de {R}osnay, {P}. and de {J}eu, {R}. and {G}ovind, {A}. and {A}l {B}itar, {A}. and {A}lbergel, {C}. and {M}unoz-{S}abater, {J}. and {R}ichaume, {P}. and {M}ialon, {A}.},
  editor = {},
  language = {{ENG}},
  abstract = {{G}lobal {L}evel-3 surface soil moisture ({SM}) maps derived from the passive microwave {SMOS} ({S}oil {M}oisture and {O}cean {S}alinity) observations at {L}-band have recently been released. {I}n this study, a comparative analysis of this {L}evel 3 product (referred to as {SMOSL}3) along with another {S}urface {SM} ({SSM}) product derived from the observations of the {A}dvanced {M}icrowave {S}canning {R}adiometer ({AMSR}-{E}) at {C}-band is presented (this latter product is referred to as {AMSRM}). {SM}-{DAS}-2, a {SSM} product produced by the {E}uropean {C}entre for {M}edium {R}ange {W}eather {F}orecasts ({ECMWF}) {L}and {D}ata {A}ssimilation {S}ystem ({LDAS}) was used to monitor both {SMOSL}3 and {AMSRM} qualities. {T}he present study was carried out from 03/2010 to 09/2011, a period during which both {SMOS} and {AMSR}-{E} products were available at global scale. {T}hree statistical metrics were used for the evaluation; the correlation coefficient ({R}), the {R}oot {M}ean {S}quared {D}ifference ({RMSD}), and the bias. {R}esults were analysed using maps of biomes and {L}eaf {A}rea {I}ndex ({LAI}). {I}t is shown that both {SMOSL}3 and {AMSRM} captured well the spatio-temporal variability of {SM}-{DAS}-2 for most of the biomes. {I}n terms of correlation values, the {SMOSL}3 product was found to better capture the {SSM} temporal dynamics in highly vegetated biomes ("tropical humid", "temperate humid", etc.) while best results for {AMSRM} were obtained over arid and semi-arid biomes ("desert temperate", "desert tropical", etc.). {F}inally, we showed that the accuracy of the remotely sensed {SSM} products is strongly related to {LAI}. {B}oth the {SMOSL}3 and {AMSRM} (marginally better) {SSM} products correlated well with the {SM}-{DAS}-2 product over regions with sparse vegetation for values of {LAI} <= 1 (these regions represent almost 50% of the pixels considered in this global study). {I}n regions where {LAI}>1, {SMOSL}3 showed better correlations with {SM}-{DAS}-2 than {AMSRM}: {SMOSL}3 had a consistent performance up to {LAI} = 6, whereas the {AMSRM} performance deteriorated with increasing values of {LAI}. {T}his study reveals that {SMOS} and {AMSR}-{E} complement one another in monitoring {SSM} over a wide range in conditions of vegetation density and that there are valuable satellite observed {SSM} data records over more than 10 years, which can be used to study land atmosphere processes.},
  keywords = {{P}assive ; {M}icrowaves ; {S}oil moisture ; {SMOS} ; {AMSR}-{E} ; {LAI} ; {L}-band ; {C}-band},
  booktitle = {},
  journal = {{R}emote {S}ensing of {E}nvironment},
  volume = {149},
  numero = {},
  pages = {181--195},
  ISSN = {0034-4257},
  year = {2014},
  DOI = {10.1016/j.rse.2014.04.006},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00011907},
}