@article{fdi:010057010,
  title = {{S}patial and temporal variability of biophysical variables in southwestern {F}rance from airborne {L}-band radiometry},
  author = {{Z}akharova, {E}. and {C}alvet, {J}. {C}. and {L}afont, {S}. and {A}lbergel, {C}. and {W}igneron, {J}. {P}. and {P}arde, {M}. and {K}err, {Y}ann and {Z}ribi, {M}ehrez},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n 2009 and 2010 the {L}-band microwave {C}ooperative {A}irborne {R}adiometer for {O}cean and {L}and {S}tudies ({CAROLS}) campaign was performed in southwestern {F}rance to support the calibration and validation of the new {S}oil {M}oisture and {O}cean {S}alinity ({SMOS}) satellite mission. {T}he {L}-band {M}icrowave {E}mission of the {B}iosphere ({L}-{MEB}) model was used to retrieve surface soil moisture ({SSM}) and the vegetation optical depth ({VOD}) from the {CAROLS} brightness temperature measurements. {T}he {CAROLS} {SSM} was compared with in situ observations at 11 sites of the {SMOSMANIA} ({S}oil {M}oisture {O}bserving {S}ystem-{M}eteorological {A}utomatic {N}etwork {I}ntegrated {A}pplication) network of {M},t,o-{F}rance. {F}or eight of them, significant correlations were observed (0.51 a parts per thousand currency sign r a parts per thousand currency sign 0.82), with standard deviation of differences ranging from 0.039 m(3) m(-3) to 0.141 m(3) m(-3). {A}lso, the {CAROLS} {SSM} was compared with {SSM} values simulated by the {A}-gs version of the {I}nteractions between {S}oil, {B}iosphere and {A}tmosphere ({ISBA}-{A}-gs) model along 20 flight lines, at a resolution of 8 km x 8 km. {A} significant spatial correlation between these two datasets was observed for all the flights (0.36 a parts per thousand currency sign r a parts per thousand currency sign 0.85). {T}he {CAROLS} {VOD} presented significant spatial correlations with the vegetation water content ({VWC}) derived from the spatial distribution of vegetation types used in {ISBA}-{A}-gs and from the {L}eaf {A}rea {I}ndex ({LAI}) simulated for low vegetation. {O}n the other hand, the {CAROLS} {VOD} presented little temporal changes, and no temporal correlation was observed with the simulated {LAI}. {F}or low vegetation, the ratio of {VOD} to {VWC} tended to decrease, from springtime to summertime. {T}he {ISBA}-{A}-gs grid cells (8 km x 8 km) were sampled every 5 m by {CAROLS} observations, at a spatial resolution of about 2 km. {F}or 83% of the grid cells, the standard deviation of the sub-grid {CAROLS} {SSM} was lower than 0.05 m(3) m(-3). {T}he presence of small water bodies within the {ISBA}-{A}-gs grid cells tended to increase the {CAROLS} {SSM} spatial variability, up to 0.10 m(3) m(-3). {A}lso, the grid cells characterised by a high vegetation cover heterogeneity presented higher standard deviation values, for both {SSM} and {VOD}.},
  keywords = {},
  booktitle = {},
  journal = {{H}ydrology and {E}arth {S}ystem {S}ciences},
  volume = {16},
  numero = {6},
  pages = {1725--1743},
  ISSN = {1027-5606},
  year = {2012},
  DOI = {10.5194/hess-16-1725-2012},
  URL = {https://www.documentation.ird.fr/hor/fdi:010057010},
}