@article{fdi:010048249,
  title = {{T}he organization and kinematics of tropical rainfall systems ground tracked at mesoscale with gages : first results from the campaigns 1999-2006 on the {U}pper {O}ueme {V}alley ({B}enin)},
  author = {{D}epraetere, {C}hristian and {G}osset, {M}arielle and {P}loix, {S}. and {L}aurent, {H}enri},
  editor = {},
  language = {{ENG}},
  abstract = {{A} dense network of rain gages, set up in the {U}pper {O}ueme {V}alley in {B}enin is used to study the spatial organization and the kinematics of the convective systems that cross the region. {T}he study area is situated under {S}oudanian climate and set up as part of the {AMMA}-{CATCH} ({A}frican {M}onsoon {M}ultidisciplinary {A}nalysis - {C}ouplage de l'{A}tmosphere {T}ropicale et du {C}ycle {H}ydrologique) observing system. {P}revious works focusing on the rainy events that occur in the {S}ahelian region of {N}iamey have shown that most of the rainfall in that region is provided by {O}rganized {C}onvective {S}ystem that cover several thousand km(2) and usually propagate with a strong westward component. {I}t was shown also that the time evolution of these {S}ahelian rainy events usually exhibits a convective peak followed by longer lasting and weaker stratiform rainfall. {T}he aim of the present study is to analyze the spatial organization and kinematics of the rainy events occurring further south under the distinct, much more humid, {S}oudanian climate. {T}hese events have been poorly documented so far and the extent to which the {S}oudanian rainfall events behave like their {S}ahelian counterparts remains unclear. {S}even years of rainfall data gathered over the {AMMA}-{CATCH} {B}enin site are studied. {A} new method called the '{A}verage {S}ynchronized {H}yetograph' ({ASH}) is proposed to analyze the kinematics of the rain patterns. {T}he method also allows the assessment of the spatial organization of the system. {A} classification of the rainy events is proposed. {I}t is based on assessing if (i) the rain patterns show a global propagation velocity and direction and (ii) if the time evolution of the rain rate within the network is typical of organized tropical {M}esoscale {C}onvective {S}ystems ({MCS}) with a well-defined convective peak. {T}he present study shows that about 55% of the events have a signature typical of those of {MCS}. {C}onversely, about 27% of rainfall events do not show evidence of being associated with {MCS} or even propagating. {T}he kinematic properties of the events classified as {MCS} appear to be globally consistent with what was observed for the {S}ahelian zone from satellite tracking; the dominant direction is south-southwest but with a large departure from this average trend; their velocity ranges mostly between 20 and 50 km/h but a significant number of events are faster than that. {MCS} remains the dominant type of events during the whole rainy season but the period between mid {J}uly and mid {A}ugust. {T}he classification of rainfall events resulting from ground tracking has been compared with {METEOSAT} satellite tracking for the years 2003 and 2004. {T}here is a significant correspondence of classes of rainfall events between the two tracking methods despite differences of scales and criterions in their definition.},
  keywords = {{R}ainfall classification ; {T}ropical rain ; {C}onvective system ; {K}inematics ; {G}round tracking ; {S}oudanian zone},
  booktitle = {},
  journal = {{J}ournal of {H}ydrology},
  volume = {375},
  numero = {1-2},
  pages = {143--160},
  ISSN = {0022-1694},
  year = {2009},
  DOI = {10.1016/j.jhydrol.2009.01.011},
  URL = {https://www.documentation.ird.fr/hor/fdi:010048249},
}