TY - JOUR
T1 - Observation and Modeling of Gravity Wave Propagation through Reflection and Critical Layers above Andes Lidar Observatory at Cerro Pachón, Chile
AU - Cao, Bing
AU - Heale, Christopher J.
AU - Guo, Yafang
AU - Liu, Alan Z.
AU - Snively, Jonathan B.
N1 - Cao, B., C. J. Heale, Y. Guo, A. Z. Liu,
and J. B. Snively (2016), Observation
and modeling of gravity wave propagation through reflection and critical
layers above Andes Lidar Observatory at Cerro Pachón, Chile, J. Geophys.
Res. Atmos., 121, 12,737–12,750,
doi:10.1002/2016JD025173
PY - 2016/11/8
Y1 - 2016/11/8
N2 - A complex gravity wave event was observed from 04:30 to 08:10 UTC on 16 January 2015 by a narrow-band sodium lidar and an all-sky airglow imager located at Andes Lidar Observatory (ALO) in Cerro Pachón (30.25∘S, 70.73∘W), Chile. The gravity wave packet had a period of 18–35 min and a horizontal wavelength of about 40–50 km. Strong enhancements of the vertical wind perturbation, exceeding10 m s−1, were found at ∼90 km and ∼103 km, consistent with nearly evanescent wave behavior near a reflection layer. A reduction in vertical wavelength was found as the phase speed approached the background wind speed near ∼93 km. A distinct three-layered structure was observed in the lidar data due to refraction of the wave packet. A fully nonlinear model was used to simulate this event, which successfully reproduced the amplitudes and layered structure seen in observations. The model results provide dynamical insight, suggesting that a double reflection occurring at two separate heights caused the large vertical wind amplitudes, while the three-layered structure in the temperature perturbation was a result of relatively stable regions at those altitudes. The event provides a clear perspective on the filtering processes to which short-period, small-scale gravity waves are subject in mesosphere and lower thermosphere.
AB - A complex gravity wave event was observed from 04:30 to 08:10 UTC on 16 January 2015 by a narrow-band sodium lidar and an all-sky airglow imager located at Andes Lidar Observatory (ALO) in Cerro Pachón (30.25∘S, 70.73∘W), Chile. The gravity wave packet had a period of 18–35 min and a horizontal wavelength of about 40–50 km. Strong enhancements of the vertical wind perturbation, exceeding10 m s−1, were found at ∼90 km and ∼103 km, consistent with nearly evanescent wave behavior near a reflection layer. A reduction in vertical wavelength was found as the phase speed approached the background wind speed near ∼93 km. A distinct three-layered structure was observed in the lidar data due to refraction of the wave packet. A fully nonlinear model was used to simulate this event, which successfully reproduced the amplitudes and layered structure seen in observations. The model results provide dynamical insight, suggesting that a double reflection occurring at two separate heights caused the large vertical wind amplitudes, while the three-layered structure in the temperature perturbation was a result of relatively stable regions at those altitudes. The event provides a clear perspective on the filtering processes to which short-period, small-scale gravity waves are subject in mesosphere and lower thermosphere.
KW - gravity waves
KW - observations
KW - modeling
KW - mesosphere
UR - https://commons.erau.edu/publication/448
U2 - 10.1002/2016JD025173
DO - 10.1002/2016JD025173
M3 - Article
SN - 2169-8996
VL - 121
JO - Journal of Geophysical Research: Atmospheres
JF - Journal of Geophysical Research: Atmospheres
ER -