@article{PAR00008068,
  title = {{P}ath-average rainfall estimation from optical extinction measurements using a large-aperture scintillometer},
  author = {{U}ijlenhoet, {R}. and {C}ohard, {J}. {M}. and {G}osset, {M}arielle},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he potential of a near-infrared large-aperture boundary layer scintillometer as path-average rain gauge is investigated. {T}he instrument was installed over a 2.4-km path in {B}enin as part of the {A}frican {M}onsoon {M}ultidisciplinary {A}nalysis ({AMMA}) {E}nhanced {O}bservation {P}eriod during 2006 and 2007. {M}easurements of the one-minute-average received signal intensity were collected for 6 rainfall events during the dry season and 16 events during the rainy season. {U}sing estimates of the signal base level just before the onset of the rainfall events, the optical extinction coefficient is estimated from the path-integrated attenuation for each minute. {T}he corresponding path-average rain rates are computed using a power-law relation between the optical extinction coefficient and rain rate obtained from measurements of raindrop size distributions with an optical spectropluviometer and a scaling-law formalism for describing raindrop size distribution variations. {C}omparisons of five-minute rainfall estimates with measurements from two nearby rain gauges show that the temporal dynamics are generally captured well by the scintillometer. {H}owever, the instrument has a tendency to underestimate rain rates and event total rain amounts with respect to the gauges. {I}t is shown that this underestimation can be explained partly by systematic differences between the actual and the employed mean power-law relation between rain rate and specific attenuation, partly by unresolved spatial and temporal rainfall variations along the scintillometer path. {O}ccasionally, the signal may even be lost completely. {I}t is demonstrated that if these effects are properly accounted for by employing appropriate relations between rain rate and specific attenuation and by adapting the pathlength to the local rainfall climatology, scintillometer-based rainfall estimates can be within 20% of those estimated using rain gauges. {T}hese results demonstrate the potential of large-aperture scintillometers to estimate path-average rain rates at hydrologically relevant scales.},
  keywords = {},
  booktitle = {},
  journal = {{J}ournal of {H}ydrometeorology},
  volume = {12},
  numero = {5},
  pages = {955--972},
  ISSN = {1525-755{X}},
  year = {2011},
  DOI = {10.1175/2011jhm1350.1},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00008068},
}