@article{PAR00001889,
  title = {{A}irborne observations of the impact of a convective system on the planetary boundary layer thermodynamics and aerosol distribution in the inter-tropical discontinuity region of the {W}est {A}frican {M}onsoon},
  author = {{F}lamant, {C}. and {C}haboureau, {J}. {P}. and {P}arker, {D}. {J}. and {T}aylor, {C}. {A}. and {C}ammas, {J}. {P}. and {B}ock, {O}. and {T}imouk, {F}ranck and {P}elon, {J}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he impact of a convective system downdraught and associated gravity current on the monsoon and harmattan flow structure as well as on aerosol vertical distribution over the {S}ahel and the {S}ahara is investigated using dropsondes and an airborne lidar. {C}omplementary ground-based and satellite observations, as well as {E}uropean {C}entre for {M}edium-range {W}eather {F}orecasts analyses are also used. {T}he mission was conducted on 5 {J}une 2006, in the framework of the {A}frican {M}onsoon {M}ultidisciplinary {A}nalysis {S}pecial {O}bserving {P}eriod. {T}he targeted area was the {S}aharan heat low region, and {M}ali in particular, over which the inter-tropical discontinuity was strongly perturbed by the convective system. {T}o the north, away from the influence of the gravity current, the atmosphere exhibited a two-layer structure, with a well mixed 3 kin deep internal boundary layer capped by a stable layer 2-2.5 km deep layer referred to as the {S}aharan aerosol layer ({SAL}). {T}he aerosol loading in the internal boundary layer (as determined by lidar) was observed to be much less than in the {SAL} above. {P}lumes of dust generated by strong low-level winds west of the {H}oggar as observed in {S}pinning {E}nhanced {V}isible and {I}nfra-{R}ed {I}mager ({SEVIRI}) images, and possibly injected in the upper {SAL} through orographic lifting, contributed to the dust loading of the elevated {SAL} over much of the domain observed by the lidar. {I}n the northernmost part of the domain investigated, the depth of the {SAL} top was decreased as the result of subsidence enhanced by the presence of an elevated jet associated with the monsoon trough and/or related to the return circulation of plain-mountain wind system involving the {A}tlas range. {A}ssociated with the gravity current passing over dust sources, a large aerosol plume was observed by means of lidar measurements and {SEVIRI} imagery. {T}he plume was seen to reach heights of approximately 3 kin above ground level a few tens of kilometres behind the leading edge. {L}idar measurements suggest that a fraction of the dust lifted by the gravity current is mixed into the {SAL}, and in some instances injected above the {SAL}.},
  keywords = {saharan aerosol layer ; gravity current ; monsoon ; harmattan ; african monsoon multidisciplinary analysis ; lidar ; dropsondes ; {SEVIRI} imagery ; {ECMWF} analyses},
  booktitle = {},
  journal = {{Q}uarterly {J}ournal of the {R}oyal {M}eteorological {S}ociety},
  volume = {133},
  numero = {626 {P}art {A}},
  pages = {1175--1189},
  ISSN = {0035-9009},
  year = {2007},
  DOI = {10.1002/qj.97},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00001889},
}