Bimodality in tropical water vapour

  title={Bimodality in tropical water vapour},
  author={Chidong Zhang and Brian E. Mapes and Brian J. Soden},
  journal={Quarterly Journal of the Royal Meteorological Society},
Probability distribution functions of tropospheric water vapour in the tropics are shown to be commonly bimodal. This bimodality implies sharp gradients between dry and moist regimes in space and time. A method of testing for and quantifying bimodality is introduced. Using this method, the bimodality of water vapour is surveyed in satellite and in situ observations, as well as in global model re‐analysis data and simulations. The bimodality suggests that the radiative drying time after an… 

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