Observations of the evening transition processes on opposing slopes of a north-south oriented mountain

Abstract:

The MATERHORN (Mountain Terrain Atmospheric Modeling and Observation) Program is a multiuniversity, multidisciplinary research initiative designed to improve numerical weather prediction in complex terrain and to better understand the physics of complex terrain flow phenomena across a wide range of scales. As part of MATERHORN, field campaigns were conducted at Dugway, UT, USA in Autumn 2012 and Spring 2013. A subset of the campaigns included dense observations along the East Slope of Granite Peak (40.096° N, -113.253° W), as well as additional observations on the opposing west facing slope. East Slope observations included five multi-sonic anemometer eddy covariance towers (two with full energy budget stations), eleven small energy budget stations, fifteen automated weather stations, a distributed temperature sensing (DTS) system, hot-film anemometry, infrared camera surface temperature observations and up to three Doppler lidars. West Slope operations were less intense with three main towers, two of which included sonic anemometry and one, which included full surface energy balance observations. For this presentation, our analysis will focus on characterizing and contrasting the response of mean wind circulations and thermodynamics variables, as well as turbulence quantities during the evening transitions on both the East Slope and West Slope when solar irradiation differences of the slope surfaces is extremely large.