@article{par00000729,
  title = {{A}nalysis of the linkages between rainfall and land surface conditions in the {W}est {A}frican monsoon through {CMAP}, {ERS}-{WSC}, and {NOAA}-{AVHRR} data - art. no. {D}24115},
  author = {{P}hilippon, {N}. and {M}ougin, {E}ric and {J}arlan, {L}. and {F}rison, {P}.{L}.},
  editor = {},
  language = {{ENG}},
  abstract = {[1] {T}he {E}uropean {R}emote {S}ensing {W}ind {S}catterometer ({ERS}-{WSC}) backscattering coefficient, {NOAA} {A}dvanced {V}ery {H}igh {R}esolution {R}adiometer ({NOAA}-{AVHRR}) {N}ormalized {D}ifference {V}egetation {I}ndex ({NDVI}), and {C}limate {P}rediction {C}enter {M}erged {A}nalysis {P}recipitation ( {CMAP}) precipitation data sets are studied over the period {A}ugust 1991 to {D}ecember 2000 to document ( 1) the interannual and intra-annual evolutions of vegetation photosynthetic activity and soil-vegetation water content over {W}est {A}frica and ( 2) their two-way links with precipitation. {O}ver the {S}ahel, at interannual timescales the strongest relationships between vegetation, soil moisture, and precipitation are observed from {J}uly to {O}ctober and when 1-month lag is considered between the parameters. {T}his delay reflects the vegetation response time to the moisture pulses that follow precipitation events. {T}he high correlation between {NDVI} and sigma_0 at interannual timescales confirms the importance of vegetation in the backscattering coefficient. {H}owever, sigma_0 shows stronger statistical links with precipitation, suggesting that this product contains additional useful information related in particular to upper soil moisture. {O}ver {G}uinea, large differences are observed between the two remote sensing products, and their relationship with precipitation at interannual timescales is weaker. {S}igma_ 0 is significantly linked to precipitation from {J}uly to {N}ovember, whereas {NDVI} does not show any significant relationship with precipitation. {NDVI} and sigma_0 serial correlations over the {S}ahel and {G}uinea suggest that a 2-month memory usually characterizes vegetation photosynthetic activity and soil-vegetation water content anomalies. {H}owever, anomalies disappearance in winter then reappearance in the following spring also suggests an interseason memory held by deep soil moisture reservoirs and deep-rooted plants. {A} composite analysis reveals that the wettest {S}ahelian rainy seasons were preceded by positive anomalies of soil-vegetation water content over {G}uinea from winter to spring. {C}ross correlations and {G}ranger causality analyses partly relate these winter to spring land surface anomalies to those recorded in precipitation during the previous autumn. {S}pring soil-vegetation water content anomalies strengthen the meridional gradient of soil-vegetation water content over the subcontinent. {T}his gradient is thought to contribute to the gradient of entropy that drives the {W}est {A}frican monsoon.},
  keywords = {},
  booktitle = {},
  journal = {{J}ournal of {G}eophysical {R}esearch {A}tmospheres},
  volume = {110},
  numero = {{D}24},
  pages = {{NIL}_40--{NIL}_54},
  ISSN = {0148-0227},
  year = {2005},
  DOI = {10.1029/2005{JD}006394},
  URL = {https://www.documentation.ird.fr/hor/par00000729},
}