Dear Colleagues,

Atmospheric flows vary in form, and the best understood are linear, often assumed to be of small amplitude. Studies of such flows can be performed computationally with a variety of simplifying assumptions using models like the Boussinesq approximation. At the other extreme, the most highly complex flows—specifically turbulent-type flows—can be moderately well understood in a statistical sense, following similitude analysis like that proposed by Kolmogoroff. However, the transition between the flow-types is harder to investigate, since it often involves a wide variety of spectral scales, and computationally requires a relatively full representation of all terms in the relevant fluid equations.

The purpose of this Special Issue is to investigate the transitional region more thoroughly. Studies may include the development of vortical motions and turbulence throughout the troposphere, stratosphere, mesosphere and ionosphere, as well as tornadoes, severe weather, wave–wave coupling, jet-stream instabilities, wave-radiation and even plasma instabilities. Observational, laboratory and numerical papers are encouraged, provided they elucidate the dynamical processes involved. For example, do buoyancy waves collapse to turbulence almost instantaneously, or do they pass through various smaller, but more complex wave-like stages in the process? Does the process depend on the nature of the wave breakdown, e.g., does collapse of a single wave differ in detail from collapse of an unstable environment produced by a spectrum of more linear waves? Of particular interest is comparisons between different models—for example, do results produced by publicly available algorithms like WRF and LES, which solve the Navier–Stokes equations directly, produce similar reliability to more carefully tuned algorithms? At what scales do the different models begin to differ in both process and detail? How can a reader know which computational results to believe? Vigorous discussion of such issues is encouraged.

Prof. Dr. Wayne Hocking
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Atmosphere is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• Waves
• Turbulence
• Transitional flows
• Coupling
• Numerical studies
• In-situ studies
• Laboratory studies
• Diffusion