@article{fdi:010064095,
  title = {{D}ecadal monitoring of the {N}iger {I}nner {D}elta flood dynamics using {MODIS} optical data},
  author = {{O}gilvie, {A}ndrew and {B}elaud, {G}illes and {D}elenne, {C}. and {B}ailly, {J}. {S}. and {B}ader, {J}ean-{C}laude and {O}leksiak, {A}. and {F}erry, {L}uc and {M}artin, {D}idier},
  editor = {},
  language = {{ENG}},
  abstract = {{W}etlands provide a vital resource to ecosystem services and associated rural livelihoods but their extent, geomorphological heterogeneity and flat topography make the representation of their hydrological functioning complex. {A} semi automated method exploiting 526 {MODIS} ({M}oderate {R}esolution {I}maging {S}pectroradiometer) 8-day 500 m resolution images was developed to study the spatial and temporal dynamics of the annual flood across the {N}iger {I}nner {D}elta over the period 2000-2011. {A} composite band ratio index exploiting the {M}odified {N}ormalised {D}ifference {W}ater {I}ndex ({MNDWI}) and {N}ormalised {D}ifference {M}oisture {I}ndex ({NDMI}) with fixed thresholds provided the most accurate detection of flooded areas out of six commonly used band ratio indices. {K}-means classified {L}andsat images were used to calibrate the thresholds. {E}stimated flooded surface areas were evaluated against additional classified {L}andsat images, previous studies and field stage data for a range of hydrological units: river stretches, lakes, floodplains and irrigated areas. {T}his method illustrated how large amounts of {MODIS} images may be exploited to monitor flood dynamics with adequate spatial and temporal resolution and good accuracy, except during the flood rise due to cloud presence. {P}revious correlations between flow levels and flooded areas were refined to account for the hysteresis as the flood recedes and for the varying amplitude of the flood. {P}eak flooded areas varied between 10 300 km(2) and 20 000 km(2), resulting in evaporation losses ranging between 12 km(3) and 21 km(3). {D}irect precipitation assessed over flooded areas refined the wetland's water balance and infiltration estimates. {T}he knowledge gained on the timing, duration and extent of the flood across the wetland and in lakes, floodplains and irrigated plots may assist farmers in agricultural water management. {F}urthermore insights provided on the wetland's flood dynamics may be used to develop and calibrate a hydraulic model of the flood in the {N}iger {I}nner {D}elta.},
  keywords = {{R}emote sensing ; {W}etland ; {MODIS} ; {F}lood dynamics ; {N}iger {I}nner {D}elta ; {W}ater balance ; {MALI} ; {NIGER} {DELTA} {INTERIEUR}},
  booktitle = {},
  journal = {{J}ournal of {H}ydrology},
  volume = {523},
  numero = {},
  pages = {368--383},
  ISSN = {0022-1694},
  year = {2015},
  DOI = {10.1016/j.jhydrol.2015.01.036},
  URL = {https://www.documentation.ird.fr/hor/fdi:010064095},
}