@article{fdi:010057032,
  title = {{T}ropical {SST} and {S}ahel rainfall : a non-stationary relationship},
  author = {{L}osada, {T}. and {R}odriguez-{F}onseca, {B}. and {M}ohino, {E}. and {B}ader, {J}. and {J}anicot, {S}erge and {M}echoso, {C}. {R}.},
  editor = {},
  language = {{ENG}},
  abstract = {{S}ea surface temperature ({SST}) anomalies in the tropical {A}tlantic have been associated with precipitation anomalies in {W}est {A}frica that form a dipole pattern with centers over the {S}ahel and the {G}ulf of {G}uinea. {W}hilst this was clear before the 1970's, the dipole pattern almost disappeared after that date, as the anti-correlation between rainfall anomalies in the {S}ahel and {G}uinea dropped abruptly. {S}imultaneously, the anti-correlations between {S}ahel rainfall and tropical {P}acific {SST}s strengthened. {I}t has been posited that these changes after the 1970's developed as rainfall over {W}est {A}frica started to co-vary with {SST}s in the global tropics. {I}n this covariability, enhanced summer rainfall over {W}est {A}frica with a monopole pattern corresponds to warmer {SST}s in the tropical {A}tlantic and {M}aritime {C}ontinent, and colder {SST}s in the tropical {P}acific and western {I}ndian {O}ceans. {T}he present paper describes the hitherto unexplored seasonal evolution of this co-variability and the physical mechanisms at work. {S}ensitivity experiments with two atmospheric general circulation models demonstrate that, after the 1970's, the impacts of {SST} anomalies in the {I}ndo-{P}acific counteract those in the {A}tlantic in terms of generating rainfall anomalies over the {S}ahel, and that this superposition of effects is primarily linear. {T}herefore, at interannual timescales, the change in the patterns of co-variability between {W}est {A}frican rainfall and tropical {SST}s can explain the non-stationary relationship between the anomalies in these two fields. {C}itation: {L}osada, {T}., {B}. {R}odriguez-{F}onseca, {E}. {M}ohino, {J}. {B}ader, {S}. {J}anicot, and {C}. {R}. {M}echoso (2012), {T}ropical {SST} and {S}ahel rainfall: {A} non-stationary relationship, {G}eophys. {R}es. {L}ett., 39, {L}12705, doi: 10.1029/2012{GL}052423.},
  keywords = {},
  booktitle = {},
  journal = {{G}eophysical {R}esearch {L}etters},
  volume = {39},
  numero = {},
  pages = {{L}12705},
  ISSN = {0094-8276},
  year = {2012},
  DOI = {10.1029/2012gl052423},
  URL = {https://www.documentation.ird.fr/hor/fdi:010057032},
}