@article{PAR00011384,
  title = {{C}larifications on the "{C}omparison between {SMOS}, {VUA}, {ASCAT}, and {ECMWF} soil moisture products over four watersheds in {US}"},
  author = {{W}agner, {W}. and {B}rocca, {L}. and {N}aeimi, {V}. and {R}eichle, {R}. and {D}raper, {C}. and de {J}eu, {R}. and {R}yu, {D}. and {S}u, {C}. {H}. and {W}estern, {A}. and {C}alvet, {J}. {C}. and {K}err, {Y}ann and {L}eroux, {D}. {J}. and {D}rusch, {M}. and {J}ackson, {T}. {J}. and {H}ahn, {S}. and {D}origo, {W}. and {P}aulik, {C}.},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n a recent paper, {L}eroux et al. compared three satellite soil moisture data sets ({SMOS}, {AMSR}-{E}, and {ASCAT}) and {ECMWF} forecast soil moisture data to in situ measurements over four watersheds located in the {U}nited {S}tates. {T}heir conclusions stated that {SMOS} soil moisture retrievals represent "an improvement [in {RMSE}] by a factor of 2-3 compared with the other products" and that the {ASCAT} soil moisture data are "very noisy and unstable." {I}n this clarification, the analysis of {L}eroux et al. is repeated using a newer version of the {ASCAT} data and additional metrics are provided. {I}t is shown that the {ASCAT} retrievals are skillful, although they show some unexpected behavior during summer for two of the watersheds. {I}t is also noted that the improvement of {SMOS} by a factor of 2-3 mentioned by {L}eroux et al. is driven by differences in bias and only applies relative to {AMSR}-{E} and the {ECWMF} data in the now obsolete version investigated by {L}eroux et al.},
  keywords = {{A}dvanced {S}catterometer ({ASCAT}) ; noise characterization ; soil moisture ; {S}oil {M}oisture and {O}cean {S}alinity ({SMOS}) ; validation ; {ETATS} {UNIS}},
  booktitle = {},
  journal = {{IEEE} {T}ransactions on {G}eoscience and {R}emote {S}ensing},
  volume = {52},
  numero = {3},
  pages = {1901--1906},
  ISSN = {0196-2892},
  year = {2014},
  DOI = {10.1109/tgrs.2013.2282172},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00011384},
}