@article{PAR00024172,
  title = {{E}xtreme austral winter precipitation events over the {S}outh-{A}merican {A}ltiplano : regional atmospheric features},
  author = {{S}egura, {H}. and {E}spinoza, {J}. {C}. and {J}unquas, {C}l{\'e}mentine and {L}ebel, {T}hierry and {V}uille, {M}. and {C}ondom, {T}homas},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {S}outh {A}merican {A}ltiplano has a marked dry season during the austral winter ({J}une to {A}ugust, {JJA}). {H}owever, during this season synoptic meteorological conditions triggering heavy precipitation can damage socioeconomic activities, often causing the loss of human lives. {U}sing daily in-situ precipitation data from 39 rain-gauge stations over the northern {A}ltiplano (18 degrees {S} -15 degrees {S}; > 3000 m.a.s.l.) for the {JJA} season, we computed the historical percentile 90 (p90) and we identified extreme rainy days with precipitation higher than p90 in the 1980-2010 period. {W}e identified 100 winter extreme precipitation events ({WEPE}s) over this region that can last between one to 16 days. {T}he {K}-means analysis was applied to anomalies of geopotential height at 500 h{P}a from {ERA}-{I}nterim data during the initial day or {D}ay(0) of {WEPE}s lasting 1 day (42 cases), 2 days (19) and more than 2 days (39). {W}e found 59 {WEPE}s characterized by an upper-level trough over the {P}eruvian-{C}hilean coast. {A}t 850 h{P}a, these 59 {WEPE}s are also associated with cold surges along the eastern {C}entral {A}ndes, indicating an association between the upper-level trough and the cold surge in developing deep convection over the northern {A}ltiplano. {A} lead-lag composite analysis further showed a significant lower- and mid-tropospheric moistening over the western {A}mazon 2 days before the onset of these 59 {WEPE}s, due to low-level northerly wind anomalies originating over equatorial {S}outh {A}merica. {T}he other 41 {WEPE}s are associated with a low-level southerly wind regime crossing the equator and a mid-and upper-level low-pressure system over the {P}eruvian-{C}hilean coast. {W}hile the low-level southerly regime enhances mid-tropospheric moisture transport from the equator towards the {A}ltiplano due to the developed shallow meridional circulation when propagating equatorward, a low-pressure system promotes intensification of upward motion, boosting the upslope moisture transport from the lowlands to the east of the {C}entral {A}ndes towards the {A}ltiplano.},
  keywords = {{W}inter extreme precipitation ; {A}ltiplano ; {C}old surges ; {U}pper-level ; trough ; {A}mazon convection ; {PEROU} ; {BOLIVIE} ; {ANDES}},
  booktitle = {},
  journal = {{C}limate {D}ynamics},
  volume = {[{E}arly access]},
  numero = {},
  pages = {[18 p.]},
  ISSN = {0930-7575},
  year = {2022},
  DOI = {10.1007/s00382-022-06240-1},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00024172},
}