Comparing tropical precipitation simulated by the Met Office NWP and climate models with satellite observations

Article English OPEN
Liu, Chunlei ; Allan, Richard P. ; Brooks, Malcolm ; Milton, Sean (2014)

Forecasts of precipitation and water vapor made by the Met Office global numerical weather prediction\ud (NWP) model are evaluated using products from satellite observations by the Special Sensor Microwave\ud Imager/Sounder (SSMIS) and Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation\ud Analysis (TMPA) for June–September 2011, with a focus on tropical areas (308S–308N). Consistent with\ud previous studies, the predicted diurnal cycle of precipitation peaks too early (by ;3 h) and the amplitude is\ud too strong over both tropical ocean and land regions. Most of the wet and dry precipitation biases, particularly\ud those over land, can be explained by the diurnal-cycle discrepancies. An overall wet bias over the\ud equatorial Pacific and Indian Oceans and a dry bias over the western Pacific warmpool and India are linked\ud with similar biases in the climate model, which shares common parameterizations with the NWP version.\ud Whereas precipitation biases develop within hours in the NWP model, underestimates in water vapor\ud (which are assimilated by the NWP model) evolve over the first few days of the forecast. The NWP simulations\ud are able to capture observed daily-to-intraseasonal variability in water vapor and precipitation,\ud including fluctuations associated with tropical cyclones.
  • References (44)
    44 references, page 1 of 5

    Allan, R. P., A. Slingo, S. F. Milton, and M. A. Brooks, 2007: Evaluation of the Met Office global forecast model using Geostationary Earth Radiation Budget (GERB) data. Quart. J. Roy. Meteor. Soc., 133, 1993-2010.

    --, C. Liu, M. Zahn, D. A. Lavers, E. Koukouvagias, and A. Bodas-Salcedo, 2013: Physically consistent responses of the global atmospheric hydrological cycle in models and observations. Surv. Geophys., doi:10.1007/s10712-012-9213-z, in press.

    Bechtold, P., J.-P. Charoureau, A. Beljaars, A. K. Betts, M. Kohler, M. Miller, and J.-L. Redelsperger, 2004: The simulation of the diurnal cycle of convective precipitation over land in a global model. Quart. J. Roy. Meteor. Soc., 130, 3119-3137.

    Bergman, J. W., and M. L. Salby, 1996: Diurnal variations of cloud cover and their relationship to climatological conditions. J. Climate, 9, 2802-2819.

    Brown, A., S. Milton, M. Cullen, B. Golding, J. Mitchell, and A. Shelly, 2012: Unified modeling and prediction of weather and climate: A 25-year journey. Bull. Amer. Meteor. Soc., 93, 1865-1877.

    Chakraborty, A., 2010: The skill of ECMWF medium-range forecasts during the Year of Tropical Convection 2008. Mon. Wea. Rev., 138, 3787-3805.

    Clayton, A. M., A. C. Lorenc, and D. M. Barker, 2012: Operational implementation of a hybrid ensemble/4D-Var global data assimilation system at the Met Office. Quart. J. Roy. Meteor. Soc., 139, 1445-1461.

    Dai, A., 2001: Global precipitation and thunderstorm frequencies. Part II: Diurnal variations. J. Climate, 14, 1112-1128.

    --, and K. E. Trenberth, 2004: The diurnal cycle and its depiction in the Community Climate System Model. J. Climate, 17, 930-951.

    --, X. Lin, and K. L. Hsu, 2007: The frequency, intensity, and diurnal cycle of precipitation in surface and satellite observations over low- and mid-latitudes. Climate Dyn., 29, 727-744.

  • Metrics
    views in OpenAIRE
    views in local repository
    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 36