The objective of this research is to estimate the numerical convergence rate of three key climate elements of hydrological and energy cycles, and to thereby quantify the error of numerical approximations at different resolutions. The three elements are: i)vertical fluxes of water vapor between the atmosphere and ocean, ii) horizontal fluxes of water vapor in boundary layer jets, and iii) sensitivity of fractional cloud cover to model resolution. The methodology will be to use a telescoping, variable resolution global model that is capable of locally resolving far more structure than are other uniform resolution climate models. The vertical boundary layer resolution will be selectively enhanced to study item (i) and the horizontal resolution will be locally enhanced to explicitly resolve mesoscale structures to study items (ii) and (iii). The study is important because it seeks to better understand water vapor transports between the oceans and atmosphere, a key component of the global water cycle. This research is supported partially by the Global Change Global Energy and Water Cycle Experiment (GEWEX).