Search Results

You are looking at 1 - 5 of 5 items for :

  • Terrain-Induced Rotor Experiment (T-Rex) x
  • Refine by Access: Content accessible to me x
Clear All
Juerg Schmidli, Gregory S. Poulos, Megan H. Daniels, and Fotini K. Chow

intermediate times. All simulations start at 1200 UTC on the previous day and were integrated for 36 h. Initialization of the land surface properties such as soil temperature, soil moisture, and snow cover using the NAM dataset resulted in poor simulation results (the near-surface flow at the central flux tower did not produce the observed valley wind shift near the end of the EOP time period). The NAM data contained large patches of snow approximately 0.5 m deep north of Independence and at the northern

Full access
Vanda Grubišić and Brian J. Billings

slot is caused by the subsidence of air in the lee of the mountain. Since the mountain range of interest is snow covered for the major part of the selected October–May period, it is important to distinguish between wave clouds and snow-covered surfaces. Often, mountain valleys remain snow free, which gives snow cover over the mountains a characteristic dendritic appearance. Also, snow shows at a slightly darker tone than clouds in our two categories. Deeper into the winter, questionable cases can

Full access
Bowen Zhou and Fotini Katopodes Chow

conditions of strong winds and/or large cloud cover, which leads to reduced net radiative surface cooling ( Van de Wiel et al. 2003 ). On clear nights with weak winds, the SBL cools rapidly. Turbulent motions are strongly damped by buoyancy stratification. The SBL goes into a quiescent state, where turbulence is suppressed over prolonged periods greater than the time scale of the dominant eddies ( Nakamura and Mahrt 2005 ). In the intermittently turbulent SBL, energetic mixing events known as turbulent

Full access
Yanping Li, Ronald B. Smith, and Vanda Grubišić

wintertime, snow cover increases surface albedo, sharply decreasing the ground sensible heating. In summertime, reduced soil moisture increases the Bowen ratio and the proportion of net radiation converted to sensible heating. To study the seasonal character of the diurnal valley circulation, a series of WRF idealized simulations have been done with a fixed valley depth ( h m = 2000 m) but with modified sensible heating. As heating is increased from 0 to 300 W m −2 , two distinct regimes are seen, with

Full access
Michael Hill, Ron Calhoun, H. J. S. Fernando, Andreas Wieser, Andreas Dörnbrack, Martin Weissmann, Georg Mayr, and Robert Newsom

. The ability of the lidar to capture the incoming elevated gust of westward winds (see dark region of lidar signal to the left of Fig. 6b ) was likely associated with enhanced backscatter return associated with low-level clouds rolling over the mountain range (or, perhaps less likely, with the lofting and suspension of snow or dust caused by the impingement of strong cross-barrier winds on the surface upwind). The up-valley flow was shown to be fully displaced 30 min later by this gust and the

Full access