@article{fdi:010077218,
  title = {{W}hat are the climate controls on delta {D} in precipitation in the {Z}ongo {V}alley ({B}olivia) ? {I}mplications for the {I}llimani ice core interpretation},
  author = {{V}imeux, {F}ran{\c{c}}oise and {G}allaire, {R}obert and {B}ony, {S}. and {H}offmann, {G}. and {C}hiang, {J}. {C}. {H}.},
  editor = {},
  language = {{ENG}},
  abstract = {{C}ontroversy has surrounded the interpretation of the water isotopic composition (delta {D} or delta(18){O}) in tropical and subtropical ice cores in {S}outh {A}merica. {A}lthough recent modeling studies using {AGCM} have provided useful constraints at interannual time scales, no direct calibration based on modem observations has been achieved. {I}n the context of the recent ice core drilling at {N}evado {I}llimani (16 degrees 39'{S}-67 degrees 47'{W}) in {B}olivia, we examine the climatic controls on the modem isotopic composition of precipitation in the {Z}ongo {V}alley, located on the northeast side of the {C}ordillera {R}eal, at about 55 km from {N}evado {I}llimani. {M}onthly precipitation samples were collected from {S}eptember 1999 to {A}ugust 2004 at various altitudes along this valley. {F}irst we examine the local and regional controls on the common delta {D} signal measured along this valley. {W}e show that (1) local temperature has definitely no control on delta {D} variations, and (2) local rainout is a poor factor to explain delta {D} variations. {W}e thus seek regional controls upstream the {V}alley potentially affecting air masses distillation. {B}ased on backtrajectory calculations and using satellite data ({TRMM} precipitation, {NOAA} {OLR}) and direct observations of precipitation ({IAEA}/{GNIP}), we show that moisture transport history and the degree of rainout upstream are more important factors, explaining seasonal delta {D} variations. {A}nalysis of a 92-yr simulation from the {ECHAM}-4 model ({T}30 version) implemented with water stable isotopes confirms our observations at seasonal time scale and emphasize the role of air masses distillation upstream as a prominent factor controlling interannual delta {D} variations. {L}astly, we focus on the isotopic depletion along the valley when air masses are lifted up. {O}ur results suggest that, if the temperature gradient between the base and the top of the {A}ndes was higher by a few degrees during the {L}ast {G}lacial {M}aximum ({LGM}), less than 10% of the glacial to interglacial isotopic variation recorded in the {I}llimani ice core could be accounted for by this temperature change. {I}t implies that the rest of the variation would originate from wetter conditions along air masses trajectory during {LGM}. ({C}) 2005 {E}lsevier {B}.{V}. {A}ll rights reserved.},
  keywords = {{S}outh {A}merica ; {A}ndes ; water stable isotopes ; calibration ; ice cores ; glacial interglacial transition ; {BOLIVIE} ; {ANDES}},
  booktitle = {},
  journal = {{E}arth and {P}lanetary {S}cience {L}etters},
  volume = {240},
  numero = {2},
  pages = {205--220},
  ISSN = {0012-821{X}},
  year = {2005},
  DOI = {10.1016/j.epsl.2005.09.031},
  URL = {https://www.documentation.ird.fr/hor/fdi:010077218},
}