Mesoscale airborne in situ and lidar observations of variance and spatial structure in the troposphere and stratosphere regions

Observations over the Canadian terrain of the Rocky Mountains and the Plains by airborne in situ and lidar measurements during two flights of the ALOHA/ANLC-93 campaign were used to study orographic effects on the tropospheric and stratospheric dynamic. The variance of the tropospheric vertical wind at 6 km altitude is found to be about 2.6 times larger for the air above rough terrain than for the air over the Plains. The amplitudes of the zonal wavenumber spectra of the tropospheric horizontal and vertical wind components were considerably larger for data collected over the Rocky Mountain area than that collected over the Plains with much higher energy at wavenumbers < 10(-5) cycles/m. Comparison of the 589 nm Rayleigh lidar data observed for the two flights for altitudes between 30 and 45 km showed higher root-mean-square amplitudes of atmospheric density fluctuations between 30 to 35 km over rough terrain. No significant difference between the two flights was seen for heights above 35 km.