Abstract
Aeolus is the first Doppler wind lidar in space. It provides unique
high-resolution measurements of horizontal wind in the sparsely-observed
upper-troposphere/lower-stratosphere (UTLS), with global coverage. In
this study, Aeolus’ ability to resolve atmospheric gravity waves (GWs)
is demonstrated. The accurate representation of these small-scale waves
is vital to properly simulate dynamics in global weather and climate
models. In a case study over the Andes, Aeolus GW measurements show
coherent phase structure from the surface to the lower stratosphere,
with wind perturbations >10 m/s, a vertical wavelength
~8 km and an along-track horizontal wavelength
~900 km. Good agreement is found between Aeolus and
colocated satellite, ground-based lidar and reanalysis data sets for
this example. Our results show that data from satellites of this type
can provide unique information on GW sources and propagation in the
UTLS, filling a key knowledge gap that underlies known major
deficiencies in weather and climate modelling.