Persistent, 10-km-scale gradients in climatological precipitation tied to topography are documented with a finescale rain and snow gauge network in the Matheny Ridge area of the Olympic Mountains of Washington State. Precipitation totals are 50% higher on top of an 800-m-high ridge relative to valleys on either side, 10 km distant. Operational fifth-generation Pennsylvania State University–NCAR...

Regional Climate Models (RCMs) are practical downscaling tools to yield regional climate information for assessing the impacts of climate variability and change. The Pacific Northwest National Laboratory (PNNL) RCM, based on the Penn State/NCAR Mesoscale Model (MM5), features a novel subgrid treatment of orographic precipitation for coupling climate, hydrologic, and ecologic processes at the wa...

A new combined local and nonlocal closure atmospheric boundary layer model called the Asymmetric Convective Model, version 2, (ACM2) was described and tested in one-dimensional form and was compared with large-eddy simulations and field data in Part I. Herein, the incorporation of the ACM2 into the fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5) is described. Model sim...

The local distribution of water vapour in the urban area of Rome has been studied using both a high resolution mesoscale model (MM5) and Earth Remote Sensing-1 (ERS-1) satellite radar data. Interferometric Synthetic Aperture Radar (InSAR) techniques, after the removal of all other geometric effects, estimate excess path length variation between two different SAR acquisitions (Atmospheric Phase ...

Planetary boundary layer (PBL) and land-surface processes have critical implications for air quality simulations. This contribution analyses the influence of three different surface/PBL schemes from the MM5 mesoscale meteorological model on the predicted photochemical pollutant concentrations using high-resolution EMICAT2000 emission model and Models-3/CMAQ chemical transport model. The Gayno–S...