The ultimate goal of this study is to improve the representation of convective transport by cumulus parameterization for mesoscale and climate models. As Part 1 of the study, we perform extensive evaluations of cloud-resolving simulations of a squall line and mesoscale convective complexes in midlatitude continent and tropical regions using the Weather Research and Forecasting model with spectral bin microphysics (SBM) and with two double-moment bulk microphysics schemes: a modified Morrison (MOR) and Milbrandt and Yau (MY2). Compared to observations, in general, SBM gives better simulations of precipitation and vertical velocity of convective cores than MOR and MY2 and therefore will be used for analysis of scale dependence of eddy transport in Part 2. The common features of the simulations for all convective systems are (1) the model tends to overestimate convection intensity in the middle and upper troposphere, but SBM can alleviate much of the overestimation and reproduce the observed convection intensity well; (2) the model greatly overestimates Z e in convective cores, especially for the weak updraft velocity; and (3) the model performs better for midlatitude convective systems than the tropical system. The modeled mass fluxes of the midlatitude systems are not sensitive to microphysics schemes but are very sensitive for the tropical case indicating strong microphysics modification to convection. Cloud microphysical measurements of rain, snow, and graupel in convective cores will be critically important to further elucidate issues within cloud microphysics schemes.

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Herein, we performed first principle calculation and classical molecular dynamics simulation to study structural optimization, band structure, and mechanical properties of differently stacked multilayer silicene. Several local energy minima have been identified as metastable conformation with different stacking mode and layer number. Bandstructure of low buckled AA bilayer silicene optimized with SCAN+rvv10 presents semiconducting behavior with a bandgap of 0.4419ev. Young's modulus of multilayer silicene shows low dependency on layer number or stacking mode. Whereas, fracture stress and strain is sensitive to the number of layers, specific stacking mode, and chirality. Furthermore, bending modulus of multilayer silicene (e.g., 0.44ev for monolayer silicene) is even lower than that of graphene, which may attribute to the flexibility of bond angle. Figure. 1 Top and side view of three 3 × 3 basic stacking mode: (a) AA; (b) AA'; (c) AB. Atoms with larger radius correspond to bottom layer. Different colours denote atoms in different buckling directions.