Exploring the effects of a nonhydrostatic dynamical core in high‐resolution aquaplanet simulations

This study explores the impact of a nonhydrostatic dynamical core in high‐resolution regional climate simulations using an aquaplanet framework. The Weather Research and Forecasting (WRF) model is used to conduct simulations with both hydrostatic (H) and nonhydrostatic (NH) solvers at horizontal grid spacings (Δx) of 36, 12, and 4 km. The differences between the H and NH simulated precipitation (ΔP) are notable even at Δx = 12 km in the intertropical convergence zone and the transition region to the drier subtropics. At gray zone grid spacing (12 km and 4 km) over the tropics, ΔP is sensitive to whether a cumulus parameterization scheme is used or not. With an idealized Witch of Agnesi land mountain, differences in the precipitation and circulation (vertical velocity) between the H and NH simulations are significant even at Δx = 36 km in the tropics due largely to the strong feedbacks related to moist processes. The differences increase as the model grid spacing and mountain half width (a) are reduced, accompanied by a shift toward a more nonhydrostatic flow regime at a = 24 km. Latent heat release drastically enhances the differences between the NH and H simulations and extends the effect of nonhydrostatic dynamics to a broader region over the mountain and downstream over the tropics. Overall, differences exist between H and NH simulations even at resolutions between 12 and 36 km, but the differences are sensitive to the representations of moist physics and other features such as horizontal diffusion used in the WRF model.

[1]  Jimy Dudhia,et al.  A Description of the Advanced Research WRF Model Version 4 , 2019 .

[2]  Song‐You Hong,et al.  Comparison of Simulated Precipitation over East Asia in Two Regional Models with Hydrostatic and Nonhydrostatic Dynamical Cores , 2016 .

[3]  Chun Zhao,et al.  Exploring a Multiresolution Approach Using AMIP Simulations , 2015 .

[4]  L. Leung,et al.  Toward the Dynamical Convergence on the Jet Stream in Aquaplanet AGCMs , 2015 .

[5]  Christiane Jablonowski,et al.  Aquaplanet Experiments Using CAM’s Variable-Resolution Dynamical Core , 2014 .

[6]  C. Dearden,et al.  Diabatic Heating and Cooling Rates Derived from In Situ Microphysics Measurements: A Case Study of a Wintertime U.K. Cold Front , 2014 .

[7]  Qing Yang,et al.  Atmospheric Moisture Budget and Spatial Resolution Dependence of Precipitation Extremes in Aquaplanet Simulations , 2014 .

[8]  Todd D. Ringler,et al.  Observed Scaling in Clouds and Precipitation and Scale Incognizance in Regional to Global Atmospheric Models , 2013 .

[9]  N. Diffenbaugh,et al.  Nonhydrostatic nested climate modeling: A case study of the 2010 summer season over the western United States , 2013 .

[10]  S. Freitas,et al.  A scale and aerosol aware stochastic convective parameterization for weather and air quality modeling , 2013 .

[11]  R. Leung,et al.  Error Characteristics of Two Grid Refinement Approaches in Aquaplanet Simulations: MPAS-A and WRF , 2013 .

[12]  Todd D. Ringler,et al.  A Hierarchical Evaluation of Regional Climate Simulations , 2013 .

[13]  Arthur A. Mirin,et al.  Exploring a Global Multiresolution Modeling Approach Using Aquaplanet Simulations , 2013 .

[14]  D. Williamson.  The effect of time steps and time‐scales on parametrization suites , 2013 .

[15]  Todd D. Ringler,et al.  A Multiscale Nonhydrostatic Atmospheric Model Using Centroidal Voronoi Tesselations and C-Grid Staggering , 2012 .

[16]  Darryl D. Holm,et al.  Extreme events in solutions of hydrostatic and non-hydrostatic climate models , 2009, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[17]  Ramaswamy,et al.  The dynamical core, physical parameterizations, and basic simulation characteristics of the atmospheric component AM3 of the GFDL global coupled model CM3 , 2011 .

[18]  K. Emanuel,et al.  A Theory for Buoyancy and Velocity Scales in Deep Moist Convection , 2009 .

[19]  Nils Wedi,et al.  A framework for testing global non‐hydrostatic models , 2009 .

[20]  William C. Skamarock,et al.  A time-split nonhydrostatic atmospheric model for weather research and forecasting applications , 2008, J. Comput. Phys..

[21]  G. Powers,et al.  A Description of the Advanced Research WRF Version 3 , 2008 .

[22]  Jimy Dudhia,et al.  Conservative Split-Explicit Time Integration Methods for the Compressible Nonhydrostatic Equations , 2007 .

[23]  T. Segawa,et al.  Nonhydrostatic Atmospheric Models and Operational Development at JMA , 2007 .

[24]  Yuh-Lang Lin,et al.  Mesoscale Dynamics: Contents , 2007 .

[25]  W. Liu,et al.  Role of Narrow Mountains in Large-Scale Organization of Asian Monsoon Convection* , 2006 .

[26]  R. Rotunno,et al.  Simulations of moist nearly neutral flow over a ridge , 2005 .

[27]  A. Staniforth,et al.  A new dynamical core for the Met Office's global and regional modelling of the atmosphere , 2005 .

[28]  W. Skamarock.  Evaluating Mesoscale NWP Models Using Kinetic Energy Spectra , 2004 .

[29]  Shian‐Jiann Lin.  A “Vertically Lagrangian” Finite-Volume Dynamical Core for Global Models , 2004 .

[30]  Hirofumi Tomita,et al.  A new dynamical framework of nonhydrostatic global model using the icosahedral grid , 2004 .

[31]  R. Pielke,et al.  Mesoscale nonhydrostatic and hydrostatic pressure gradient forces-theory , 2003 .

[32]  Slobodan Nickovic,et al.  An Alternative Approach to Nonhydrostatic Modeling , 2001 .

[33]  A. Buzzi,et al.  A numerical study of moist stratified flows over isolated topography , 2001 .

[34]  I. Roulstone,et al.  Royal Meteorological Society discussion meeting on ‘New directions in mathematical modelling in numerical weather prediction’, 16th February, 2000. , 2000 .

[35]  Richard Neale,et al.  A standard test for AGCMs including their physical parametrizations: I: the proposal , 2000 .

[36]  Song-You Hong,et al.  Implementation of Prognostic Cloud Scheme for a Regional Spectral Model , 1998 .

[37]  S. Raman,et al.  A review of non-hydrostatic numerical models for the atmosphere , 1995 .

[38]  Kazuo Saito,et al.  Hydrostatic and Non-Hydrostatic Simulations of Moist Convection: Applicability of the Hydrostatic Ap , 1995 .

[39]  J. Dudhia.  A Nonhydrostatic Version of the Penn State–NCAR Mesoscale Model: Validation Tests and Simulation of an Atlantic Cyclone and Cold Front , 1993 .

[40]  R. Sinnott.  Virtues of the Haversine , 1984 .

[41]  Wen-yih Sun.  Numerical Analysis for Hydrostatic and Nonhydrostatic Equations of Inertial-Internal Gravity Waves , 1984 .

[42]  Jeng-Ming Chen,et al.  Effects of Cloud Seeding, Latent Heat of Fusion, and Condensate Loading on Cloud Dynamics and Precipitation Evolution: A Numerical Study. , 1982 .

[43]  Joseph B. Klemp,et al.  The Effects of Moisture on Trapped Mountain Lee Waves , 1982 .

[44]  D. Durran,et al.  On the Effects of Moisture on the Brunt-Väisälä Frequency. , 1982 .

[45]  I. Orlanski.  The Quasi-Hydrostatic Approximation , 1981 .

[46]  H. D. Orville,et al.  The dynamics and thermodynamics of precipitation loading , 1975 .

[47]  J. Holton.  An introduction to dynamic meteorology , 2004 .

[48]  R. S. Scorer,et al.  Theory of waves in the lee of mountains , 1949 .

[49]  Paul Queney,et al.  The Problem of Air Flow Over Mountains: A Summary of Theoretical Studies , 1948 .