Abstract: The interactions between low-frequency transients and synoptic-scale eddies are examined. The 300-mb data from 1981 to 1986 analyzed by the ECMWF are used to calculate the height tendency of the slow transients due to ...

Abstract: The stability of free and forced planetary waves in a ? plane channel is investigated with a barotropic model. The equilibrium flows that are considered have the gravest possible scale in the meridional direction and a ...

Abstract: A primitive equations dry atmospheric model is used to investigate the atmospheric response to a tropical diabatic forcing pattern and explore how the atmospheric response changes as a function of the amplitude of the ...

Abstract: It is desirable to filter the unpredictable components from a medium-range forecast. Such a filtered forecast can be obtained by averaging an ensemble of predictions that started from slightly different initial atmospheric ...

Abstract: Three-dimensional flows for which q=??(p)? where q is the potential vorticity, ? the stream function and ? some arbitrary function of pressure, are examined. It is found that flows which satisfy this condition and are quite ...

Abstract: The resonance of stationary waves forced by topography is examined using a quasi-geostrophic model on a beta-plane channel. It is shown analytically that among the factors favoring the resonance of large, rather than ...

Abstract: The middle-latitude standing wave problem is investigated by means of a quasi-geostrophic, linear, steady-state model in which the zonal current is perturbed by the lower boundary topography and by a distribution of heat ...

Abstract: Numerical experiments have been performed to determine whether it is possible to improve the quality of atmospheric forecasts by using the average of two predictions starting from slightly perturbed initial conditions. The ...

Abstract: Based on the bivariate Madden?Julian oscillation (MJO) index defined by Wheeler and Hendon and 25 yr (1979?2004) of pentad data, the association between the North Atlantic Oscillation (NAO) and the MJO on the intraseasonal ...

Abstract: A long integration of a primitive equation dry atmospheric model with time-independent forcing under boreal winter conditions is analyzed. A variety of techniques such as time filtering, space?time spectral analysis, and ...