A distinct front-like structure was observed in CIPS Ice Water Content and Albedo images on 16 June 2010 at high latitudes. Simultaneous observations of this mesospheric front were made with the OSIRIS and SMR instruments on the limb viewing Odin satellite.

Mesospheric fronts appear as structures similar to gravity waves in CIPS images and manifest them self as a disturbance in cloud brightness when propagating through an NLC layer. They can also be observed with different observation methods such as all-sky airglow images, lidar measurements, and pictures from ground-based cameras. The physical processes that could be responsible for generating mesospheric fronts have been discussed in recent papers and it has been proposed that mesospheric fronts appear in ducting conditions and are generated from intense wind shear, a temperature inversion layer or a combination of these two.

At the time of the observation of the mesospheric front in our study, the Odin satellite was run in a special mesospheric mode with short limb scans that allowed for multiple lines of sight through the cloud volume, thus enabling a tomographic retrieval of cloud structures in 2D. Since the resolution of the tomographic retrievals is as fine as 1 km in the vertical and 200 km along track it is possible to perform a detailed analysis of NLC properties, mesospheric temperature and water vapor across the front. The Odin satellite observed the frontal structure perpendicular to the wave propagation during four consecutive orbits with roughly 90 min difference, thus enabling the investigation of the evolution of the front in time.

In this project, we focus on how a mesospheric front propagating through an NLC layer affects cloud properties such as cloud brightness, ice mass density, mean radius and number density. We also investigate the dynamics and the background atmosphere in the vicinity of the front.