Systematic model forecast error in Rossby wave structure

Article English OPEN
Gray, Suzanne L. ; Dunning, C. M. ; Methven, John ; Masato, Giacomo ; Chagnon, Jeffrey M. (2014)
  • Publisher: American Geophysical Union
  • Related identifiers: doi: 10.1002/2014GL059282
  • Subject:
    arxiv: Physics::Atmospheric and Oceanic Physics

Diabatic processes can alter Rossby wave structure; consequently errors arising from model processes propagate downstream. However, the chaotic spread of forecasts from initial condition uncertainty renders it difficult to trace back from root mean square forecast errors to model errors. Here diagnostics unaffected by phase errors are used, enabling investigation of systematic errors in Rossby waves in winter-season forecasts from three operational centers. Tropopause sharpness adjacent to ridges decreases with forecast lead time. It depends strongly on model resolution, even though models are examined on a common grid. Rossby wave amplitude reduces with lead time up to about five days, consistent with under-representation of diabatic modification and transport of air from the lower troposphere into upper-tropospheric ridges, and with too weak humidity gradients across the tropopause. However, amplitude also decreases when resolution is decreased. Further work is necessary to isolate the contribution from errors in the representation of diabatic processes.
  • References (21)
    21 references, page 1 of 3

    Brennan, M. J., G. M. Lackmann, and K. M. Mahoney (2008), Potential vorticity (PV) thinking in operations: The utility of nonconservation, Weather Forecast., 23, 168-182, doi:10.1175/2007WAF20060441.

    Browning, K. A., and N. M. Roberts (1994), Structure of a frontal cyclone, Q. J. R. Meteorol. Soc., 120, 1535-1557.

    Butchart, N., and E. E. Remsberg (1986), The area of the stratospheric polar vortex as a diagnostic for tracer transport on an isentropic surface, J. Atmos. Sci., 43, 1319-1339, doi:10.1175/1520-0469(1986)043<1319:TAOTSP>2.0.CO;2.

    Chagnon, J., S. L. Gray, and J. Methven (2013), Diabatic processes modifying potential vorticity in a North Atlantic cyclone, Q. J. R. Meteorol. Soc., 139, 1270-1282, doi:10.1002/qj.2037.

    Davies, H., and M. Didone (2013), Diagnosis and dynamics of forecast error growth, Mon. Weather Rev., 141, 2483-2501, doi:10.1175/MWR-D-12-00242.1.

    Dawson, A., T. N. Palmer, and S. Corti (2012), Simulating regime structures in weather and climate prediction models, Geophys. Res. Lett., 39, L21805, doi:10.1029/2012GL053284.

    Dirren, S., M. Didone, and H. C. Davies (2003), Diagnosis of “forecast-analysis” differences of a weather prediction system, Geophys. Res. Lett., 30(20), 2060, doi:10.1029/2003GL017986.

    Esler, J. G. (2004), Benjamin-Feir instability of Rossby waves on a jet, Q. J. R. Meteorol. Soc., 130, 1611-1630, doi:10.1256/qj.03.74.

    Forster, C., and V. Wirth (2000), Radiative decay of idealized stratospheric filaments in the troposphere, J. Geophys. Res., 105, 10,169-10,184, doi:10.1029/2000JD900052.

    Frame, T. H. A., M. H. P. Ambaum, S. L. Gray, and J. Methven (2011), Ensemble prediction of transitions of the North Atlantic eddy-driven jet, Q. J. R. Meteorol. Soc., 137, 1288-1297, doi:10.1002/qj.829.

  • Related Research Results (1)
  • Metrics
    0
    views in OpenAIRE
    0
    views in local repository
    32
    downloads in local repository

    The information is available from the following content providers:

    From Number Of Views Number Of Downloads
    Central Archive at the University of Reading - IRUS-UK 0 32
Share - Bookmark