Nonhydrostatic Atmospheric Modeling Using a Combined Cartesian Grid

Hiroe Yamazaki Division of Earth and Planetary Sciences, Graduate School of Science, Kyoto University, Kyoto, Japan

Search for other papers by Hiroe Yamazaki in
Current site
Google Scholar
PubMed
Close
and
Takehiko Satomura Division of Earth and Planetary Sciences, Graduate School of Science, Kyoto University, Kyoto, Japan

Search for other papers by Takehiko Satomura in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

A new method for representing topography on a Cartesian grid is applied to a two-dimensional nonhydrostatic atmospheric model to achieve highly precise simulations over steep terrain. The shaved cell method based on finite-volume discretization is used along with a cell-combining approach in which small cut cells are combined with neighboring cells either vertically or horizontally. A unique staggered arrangement of variables enables quite simple computations of momentum equations by avoiding the evaluation of surface pressure and reducing the computational cost of combining cells for the velocity variables. The method successfully reproduces flows over a wide range of slopes, including steep slopes where significant errors are observed in a model using conventional terrain-following coordinates. The advantage of horizontal cell combination on extremely steep slopes is also demonstrated.

Corresponding author address: Hiroe Yamazaki, Division of Earth and Planetary Sciences, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan. Email: yamazaki_h@kugi.kyoto-u.ac.jp

Abstract

A new method for representing topography on a Cartesian grid is applied to a two-dimensional nonhydrostatic atmospheric model to achieve highly precise simulations over steep terrain. The shaved cell method based on finite-volume discretization is used along with a cell-combining approach in which small cut cells are combined with neighboring cells either vertically or horizontally. A unique staggered arrangement of variables enables quite simple computations of momentum equations by avoiding the evaluation of surface pressure and reducing the computational cost of combining cells for the velocity variables. The method successfully reproduces flows over a wide range of slopes, including steep slopes where significant errors are observed in a model using conventional terrain-following coordinates. The advantage of horizontal cell combination on extremely steep slopes is also demonstrated.

Corresponding author address: Hiroe Yamazaki, Division of Earth and Planetary Sciences, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan. Email: yamazaki_h@kugi.kyoto-u.ac.jp

Save
  • Adcroft, A., C. Hill, and J. Marshall, 1997: Representation of topography by shaved cells in a height coordinate ocean model. Mon. Wea. Rev., 125 , 2293–2315.

    • Search Google Scholar
    • Export Citation
  • Arakawa, A., and V. R. Lamb, 1977: Computational design of the basic dynamical processes of the UCLA general circulation model. Methods Comput. Phys., 17 , 173–265.

    • Search Google Scholar
    • Export Citation
  • Asselin, R., 1972: Frequency filter for time integrations. Mon. Wea. Rev., 100 , 487–490.

  • Bryan, K., 1969: A numerical method for the study of the circulation of the world ocean. J. Comput. Phys., 4 , 347–376.

  • Calhoun, D., and R. J. LeVeque, 2000: A Cartesian grid finite-volume method for the advection-diffusion equation in irregular geometries. J. Comput. Phys., 157 , 143–180.

    • Search Google Scholar
    • Export Citation
  • Durran, D. R., and J. B. Klemp, 1983: A compressible model for the simulation of moist mountain waves. Mon. Wea. Rev., 111 , 2341–2361.

    • Search Google Scholar
    • Export Citation
  • Gallus, W. A., and J. B. Klemp, 2000: Behavior of flow over step orography. Mon. Wea. Rev., 128 , 1153–1164.

  • Huppert, H. E., and J. W. Miles, 1969: Lee waves in a stratified flow. Part 3: Semi-elliptical obstacle. J. Fluid Mech., 35 , 481–496.

    • Search Google Scholar
    • Export Citation
  • Janjić, Z. I., 1989: On the pressure gradient force error in σ-coordinate spectral models. Mon. Wea. Rev., 117 , 2285–2292.

    • Search Google Scholar
    • Export Citation
  • Kirkpatrick, M. P., S. W. Armfield, and J. H. Kent, 2003: A representation of curved boundaries for the solution of the Navier–Stokes equations on a staggered three-dimensional Cartesian grid. J. Comput. Phys., 184 , 1–36.

    • Search Google Scholar
    • Export Citation
  • Klemp, J. B., and D. K. Lilly, 1978: Numerical simulation of hydrostatic mountain waves. J. Atmos. Sci., 35 , 78–107.

  • Klemp, J. B., and R. B. Wilhelmson, 1978: The simulation of three-dimensional convective storm dynamics. J. Atmos. Sci., 35 , 1070–1096.

    • Search Google Scholar
    • Export Citation
  • Klemp, J. B., W. C. Skamarock, and J. Dudhia, 2007: Conservative split-explicit time integration methods for the compressible nonhydrostatic equations. Mon. Wea. Rev., 135 , 2897–2913.

    • Search Google Scholar
    • Export Citation
  • Lock, S-J., 2008: Development of a new numerical model for studying microscale atmospheric dynamics. Ph.D. thesis, University of Leeds, 158 pp.

  • Mesinger, F., Z. I. Janjic, S. Nickovic, D. Gavrilov, and D. G. Deaven, 1988: The step-mountain coordinate: Model description and performance for cases of Alpine lee cyclogenesis and for a case of an Appalachian redevelopment. Mon. Wea. Rev., 116 , 1493–1518.

    • Search Google Scholar
    • Export Citation
  • Miles, J. W., and H. E. Huppert, 1968: Lee waves in a stratified flow. Part 2: Semi-circular obstacle. J. Fluid Mech., 33 , 803–814.

    • Search Google Scholar
    • Export Citation
  • Mittal, R., and G. Iaccarino, 2003: Immersed boundary methods. Annu. Rev. Fluid Mech., 37 , 239–261.

  • Mittal, R., C. Bonilla, and H. S. Udaykumar, 2003: Cartesian grid methods for simulating flows with moving boundaries. Computational Methods and Experimental Measurements XI, C. A. Brebbia, G. M. Carlomagno, and P. Anagnostopoulos, Eds., WIT Press, 557–566.

    • Search Google Scholar
    • Export Citation
  • Saito, K., T. Kato, H. Eito, and C. Muroi, 2001: Documentation of the Meteorological Research Institute/Numerical Prediction Division unified nonhydrostatic model. Tech. Rep. 42, Meteorological Research Institute, 133 pp.

    • Search Google Scholar
    • Export Citation
  • Satoh, M., 2002: Conservative scheme for the compressible nonhydrostatic models with the horizontally explicit and vertically implicit time integration scheme. Mon. Wea. Rev., 130 , 1227–1245.

    • Search Google Scholar
    • Export Citation
  • Satomura, T., 1989: Compressible flow simulations on numerically generated grids. J. Meteor. Soc. Japan, 67 , 473–482.

  • Satomura, T., and S. Akiba, 2003: Development of high-precision nonhydrostatic atmospheric model (1): Governing equations. Ann. Disaster Prev. Res. Inst. Kyoto Univ., 46B , 331–336. [Available online at http://www.dpri.kyoto-u.ac.jp/dat/nenpo/no46/46b0/a46b0t32.pdf].

    • Search Google Scholar
    • Export Citation
  • Schär, C., D. Leuenberger, O. Fuhrer, D. Lüthi, and C. Girard, 2002: A new terrain-following vertical coordinate for atmospheric prediction models. Mon. Wea. Rev., 130 , 2459–2480.

    • Search Google Scholar
    • Export Citation
  • Semtner, A. J., and Y. Mintz, 1977: Numerical simulation of the Gulf Stream and midocean eddies. J. Phys. Oceanogr., 7 , 208–230.

  • Steppeler, J., H. W. Bitzer, M. Minotte, and L. Bonaventura, 2002: Nonhydrostatic atmospheric modeling using a z-coordinate representation. Mon. Wea. Rev., 130 , 2143–2149.

    • Search Google Scholar
    • Export Citation
  • Steppeler, J., and Coauthors, 2006: Prediction of clouds and rain using a z-coordinate nonhydrostatic model. Mon. Wea. Rev., 134 , 3625–3643.

    • Search Google Scholar
    • Export Citation
  • Sundqvist, H., 1976: On vertical interpolation and truncation in connection with use of sigma system models. Atmosphere (Toronto), 14 , 37–52.

    • Search Google Scholar
    • Export Citation
  • Thompson, J. F., Z. U. A. Warsi, and C. W. Mastin, 1985: Numerical Grid Generation: Foundations and Applications. Elsevier Science, 483 pp.

    • Search Google Scholar
    • Export Citation
  • Thuburn, J., and T. J. Woollings, 2005: Vertical discretizations for compressible Euler equation atmospheric models giving optimal representation of normal modes. J. Comput. Phys., 203 , 386–404.

    • Search Google Scholar
    • Export Citation
  • Tomita, H., and M. Satoh, 2004: A new dynamical framework of nonhydrostatic global model using the icosahedral grid. Fluid Dyn. Res., 34 , 357–400.

    • Search Google Scholar
    • Export Citation
  • Tseng, Y-H., and J. H. Ferziger, 2003: A ghost-cell immersed boundary method for flow in complex geometry. J. Comput. Phys., 192 , 593–623.

    • Search Google Scholar
    • Export Citation
  • Udaykumar, H. S., W. Shyy, and M. M. Rao, 1996: A mixed Eulerian-Lagrangian method for fluid flows with complex and moving boundaries. Int. J. Numer. Methods Fluids, 22 , 691–712.

    • Search Google Scholar
    • Export Citation
  • Udaykumar, H. S., R. Mittal, P. Rampunggoon, and A. Khanna, 2001: A sharp interface Cartesian grid method for simulating flows with complex moving boundaries. J. Comput. Phys., 174 , 345–380.

    • Search Google Scholar
    • Export Citation
  • Walko, R. L., and R. Avissar, 2008: The Ocean–Land–Atmosphere Model (OLAM). Part II: Formulation and tests of the nonhydrostatic dynamic core. Mon. Wea. Rev., 136 , 4045–4062.

    • Search Google Scholar
    • Export Citation
  • Xue, M., K. K. Droegemeier, and V. Wong, 2000: The advanced regional prediction system (ARPS)—A multi-scale nonhydrostatic atmospheric simulation and prediction model. Part I: Model dynamics and verification. Meteor. Atmos. Phys., 75 , 161–193.

    • Search Google Scholar
    • Export Citation
  • Yamazaki, H., and T. Satomura, 2008: Vertically combined shaved cell method in a z-coordinate nonhydrostatic atmospheric model. Atmos. Sci. Lett., 9 , 171–175. doi:10.1002/asl.187.

    • Search Google Scholar
    • Export Citation
  • Ye, T., R. Mittal, H. S. Udaykumar, and W. Shyy, 1999: An accurate Cartesian grid method for viscous incompressible flows with complex immersed boundaries. J. Comput. Phys., 156 , 209–240.

    • Search Google Scholar
    • Export Citation
  • Zängl, G., 2002: An improved method for computing horizontal diffusion in a sigma-coordinate model and its application to simulations over mountainous topography. Mon. Wea. Rev., 130 , 1423–1432.

    • Search Google Scholar
    • Export Citation
  • Zängl, G., 2003: A generalized sigma-coordinate system for the MM5. Mon. Wea. Rev., 131 , 2875–2884.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 145 60 10
PDF Downloads 103 42 8