Cheng Yuen Chung Armstrong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 146-150). / Acknowledgements --- p.i / Abstract --- p.ii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- South China Orography --- p.2 / Chapter 1.2 --- Winter Monsoon Surges in Southern China --- p.3 / Chapter 1.3 --- Forecasts on the Northerly Surges and Effects on Local Weather --- p.5 / Chapter 1.4 --- Motivations and Objectives --- p.6 / Chapter 2 --- The Numerical Model --- p.8 / Chapter 2.1 --- Model Domain and Grid Structure --- p.10 / Chapter 2.1.1 --- Model domain --- p.10 / Chapter 2.1.2 --- Grid structure --- p.11 / Chapter 2.2 --- Governing Equations --- p.11 / Chapter 2.3 --- Finite Differencing Schemes and Lateral Boundaries --- p.14 / Chapter 2.3.1 --- Spatial differencing scheme --- p.15 / Chapter 2.3.2 --- Time integration scheme --- p.16 / Chapter 2.3.3 --- Choice of time step --- p.17 / Chapter 2.3.4 --- Lateral boundary conditions --- p.20 / Chapter 2.4 --- Development of Unevenly Spaced Vertical Levels --- p.20 / Chapter 2.4.1 --- Differencing scheme in vertical direction --- p.22 / Chapter 2.4.2 --- Integration of the hydrostatic equation --- p.26 / Chapter 2.4.3 --- Consideration of consistency in vertical and horizontal resolution --- p.27 / Chapter 2.5 --- Boundary Layer Physics --- p.30 / Chapter 2.5.1 --- Basic theory --- p.31 / Chapter 2.5.2 --- Turbulence closure --- p.33 / Chapter 2.5.3 --- Budget equation for turbulent kinetic energy --- p.36 / Chapter 2.5.4 --- Static and dynamic stability --- p.38 / Chapter 2.5.5 --- The logorithmic wind profile --- p.40 / Chapter 2.5.6 --- Bulk aerodynamics --- p.42 / Chapter 2.5.7 --- Boundary layer parameterization schemes of the model --- p.44 / Chapter 2.6 --- Parameterization of Precipitations --- p.48 / Chapter 3 --- Numerical Experiments --- p.53 / Chapter 3.1 --- Simulations From the Original Version --- p.54 / Chapter 3.2 --- Simulations From the Unevenly Spaced Version --- p.67 / Chapter 3.2.1 --- 10unevenly spaced levels simulation --- p.67 / Chapter 3.2.2 --- 17unevenly spaced levels simulation with enhanced PBL resolution --- p.71 / Chapter 3.3 --- Simulations With the Modified Boundary Layer Parameterization Schemes --- p.73 / Chapter 4 --- Case Studies of Northerly Cold Surges --- p.77 / Chapter 4.1 --- Lag-correlation Analysis --- p.78 / Chapter 4.2 --- Case Study I --- p.80 / Chapter 4.2.1 --- General descriptions --- p.81 / Chapter 4.2.2 --- Forecasts in ROHK --- p.84 / Chapter 4.2.3 --- 500hPa vorticity --- p.84 / Chapter 4.2.4 --- Numerical simulations --- p.87 / Chapter 4.3 --- Case Study II --- p.90 / Chapter 4.3.1 --- General descriptions --- p.90 / Chapter 4.3.2 --- Potential temperature advection --- p.90 / Chapter 5 --- A Forecast Index for Northerly Cold Surges --- p.99 / Chapter 5.1 --- The Internal Froude Number --- p.100 / Chapter 5.2 --- Case Investigations of a Critical Internal Froude Number over Nan Ling Ranges --- p.102 / Chapter 5.2.1 --- Case study I --- p.103 / Chapter 5.2.2 --- Case study II --- p.104 / Chapter 5.2.3 --- Case study on other events --- p.105 / Chapter 6 --- Conclusion --- p.112 / Appendices --- p.115 / Chapter A --- Computational Dispersion of Shallow Water Equation in f-Plane --- p.115 / Chapter B --- Rossby Radius in a Continuously Stratified Fluid --- p.119 / Chapter C --- Boussinesq Approximation of Navier-Stokes Equation --- p.123 / Chapter D --- Depth of the Neutral Boundary Layer --- p.125 / Chapter E --- Lag-correlation Analysis --- p.128 / Chapter F --- Fortran Source Code of the Numerical Model --- p.131 / Bibliography --- p.146