Wednesday, 22 May 2002: 8:30 AM
Terrain and Ambient wind effects on the warming footprint of a wind machine
Initial analyses are presented from five meteorological experiments conducted in July and early August of 2001 to characterize temperature and wind patterns in a large vineyard situated approximately 11 kilometers southwest of Richland, Washington, during clear, light wind, nighttime periods. The vineyard is in undulating topography on a small plateau between Badger Mountain and Badger Canyon, and has multiple drainage gullies and gently rolling terrain. The experiments focused on the evolution of spatial patterns of temperature over rolling terrain, the development of vertical variations in temperature above the vineyard, and the effects of a 12-m tall frost protection fan on profiles and spatial patterns of temperature surrounding the fan. A final experiment attempted to place our previous experiments within a larger mesoscale context by measuring temperatures and winds both within the vineyard and in a much larger area surrounding the vineyard.
Results demonstrated that the coldest air drains from the vineyard, pooling in topographical depressions and flowing into lower-lying land adjacent to the vineyard. Shallow inversions of about 5 °C were found to develop within the depressions during clear, light wind conditions. The 12-meter high vineyard fan produced atmospheric mixing in the near-surface layer and above the vineyard causing surface temperature increases of several degrees C within a 100-m radius of the fan.
Supplementary URL: