Variations of dry deposition velocity for S02 due to terrain-forced mesoscale circulations have been explored for northeast Colorado and south Florida. A mesoscale numerical model was used to obtain the wind and turbulence data needed to calculate the deposition velocities. Computations were performed both with and without consideration of observed land use characteristics. The results indicate...

The Atlantic Tradewind Ocean-Atmosphere Mesoscale Interaction Campaign (ATOMIC) took place in January–February, 2020. It was designed to understand the relationship between shallow convection and large-scale environment trade-wind regime. A Lagrangian large eddy simulation, following trajectory of a boundary-layer airmass, can reproduce transition trade cumulus organization from “sugar” “flower...

A method of deriving new relationships between near-surface turbulent fluxes and vertical differences of wind speed and potential temperature between two levels in the atmospheric surface layer from simplified second-order turbulence closure models is presented. The paper aims at a coherent treatment of fair-weather conditions and the asymptotic free convection limit. The traditionally used rep...

In aquatic ecosystems, primary production (the transformation of inorganic materials and light into living matter by photosynthesis) is operated mainly by small, unicellular algae that float freely in the upper layers of oceans and lakes and are collectively called phytoplankton, see for an illustration the phytoplankters depicted in figure 1. Since phytoplankton need light, they are confined t...

We present enhanced physics-based finite element schemes for two families of turbulence models, the NS-ω models and the Stolz-Adams approximate deconvolution models. These schemes are delicate extensions of a method created for the Navier-Stokes equations in Rebholz 2007 , that achieve high physical fidelity by admitting balances of both energy and helicity that match the true physics. The sche...

The basic science of turbulence has been known for many years, yet the knowledge has hardly become a part of operational aviation turbulence forecasting. The history of turbulence forecasting, which has primarily concentrated at elevations above the boundary layer, has been an amalgamation of empirical rules of thumb and forecaster intuition, not of strong theory and conceptual models. Turbulen...

Verification of two months, April and May 1997, of 48-h mesoscale model simulations of the atmospheric state around Greenland are presented. The simulations are performed with a modified version of The Pennsylvania State University–National Center for Atmospheric Research fifth-generation Mesoscale Model (MM5), referred to as the Polar MM5. Global atmospheric analyses as well as automatic weath...

Mean flow predictions obtained from a host of turbulence models were found to be in poor agreement with recent direct numerical simulation results for turbulent flow distal to an idealized eccentric stenosis. Many of the widely used turbulence models, including a large eddy simulation model, were unable to accurately capture the poststenotic transition to turbulence. The results suggest that ef...

Occurrence of laminar separation bubbles on solid walls of an elliptic cylinder has been simulated using a recently developed transitional model for boundary layer flows. Computational method is based on the solution of the Reynolds averaged Navier-Stokes (RANS) equations and the eddy-viscosity concept. Transitional model tries to simulate streamwise fluctuations, induced by freestream turbulen...

Climatically important low-level clouds are commonly misrepresented in climate models. The FAst-physics System TEstbed and Research (FASTER) Project has constructed case studies from the Atmospheric Radiation Measurement Climate Research Facility’s Southern Great Plain site during the RACORO aircraft campaign to facilitate research on model representation of boundary-layer clouds. This paper fo...