a fluid, which is stable under the action of buoyancy, can oscillate under the influence of buoyancy and coriolis forces. the resulting ageostrophic oscillations with a frequency between coriolis and buoyancy frequencies are called inertia-gravity waves, hereafter igws. in this study we investigate the generation and propagation of igws over iran. to this end, the weather research and forecasti...

Decaying trapped waves exert a drag on the large-scale flow. The two most studied mechanisms for such decay are boundary-layer dissipation and leakage into the stratosphere. If the waves dissipate in the boundary layer, they exert a drag near the surface, whereas if they leak into the stratosphere, the drag is exerted at the level where the waves dissipate aloft. Although each of these decay me...

The stratosphere and the troposphere exhibit a strong coupling during the winter months. However, the coupling mechanisms between the respective vertical layers are not fully understood. An idealized spectral core dynamical model is utilized in the present study in order to clarify the coupling timing, location and mechanisms. Since the coupling between the winter stratosphere and troposphere i...

The temperatures in Jupiter's stratosphere, as measured by the Galileo Atmosphere Structure Instrument (ASI), show fluctuations that have been interpreted as gravity waves. We present a detailed description of these fluctuations, showing that they are not likely to be due to either measurement error or isotropic turbulence. These fluctuations share features with gravity waves observed in the te...

Temperatures in the tropical tropopause layer (TTL) play an important role in stratosphere–troposphere exchange and in the formation and maintenance of thin cirrus clouds. Many previous studies have examined the contributions of extratropical and equatorial waves to the TTL using coarse-vertical-resolution satellite and reanalysis data. In this study, the authors provide new insight into the ro...

Water vapor in the lower stratosphere exhibits localized maximum values during Northern Hemisphere summer in the Asian and North American (NA) monsoon regions. The processes maintaining these maxima are not well understood. We analyze the variability of water vapor in the monsoon regions based on Aura Microwave Limb Sounder satellite observations during 2005–2013 and quantify links to deep conv...

Decaying trapped waves exert a drag on the large-scale flow. The two most studied mechanisms for such decay are boundary layer dissipation and leakage into the stratosphere. If the waves dissipate in the boundary layer, they exert a drag near the surface, whereas, if they leak into the stratosphere, the drag is exerted at the level where the waves dissipate aloft. Although each of these decay m...

[1] We present a hypothesis that the known formation of nitric acid hydrates in lee-wave ice clouds produces a ‘‘standing crop’’ of nitric acid trihydrate (NAT) particles, and that growth and sedimentation of these particles efficiently denitrifies the polar stratosphere. Simulations using a simple two-dimensional model illustrate that the large NAT number concentrations produced in lee waves (...