Abstract:
This dataset contains wind speed and direction in the middle atmosphere above Davis, Antarctica. The experiment runs continuously. Data are collected and stored every two minutes (excluding downtime for maintenance and data transfer) for heights in the range 64km to 102km at 2km intervals. Analysis of the source data yields parameters describing the strength and character of the radar echo and,
... when certain acceptance criteria are met, the wind speed. The requirement to meet acceptance criteria results in a data rate that may be less than the sampling rate.
Data from 1994 to 2012 are currently held.
The dataset is the output of (Australian) Antarctic Science Advisory Committee project number 674. The data set is Standalone. MFSA stands for Medium Frequency Spaced Array.
Project objectives:
Dynamical coupling processes in the Antarctic middle atmosphere continue to challenge both our understanding of the region and our ability to predict the environment's response to rising greenhouse gas concentrations. The Davis MF radar was amongst the first instruments in Antarctica to investigate the dynamics of the mesosphere/lower thermosphere (MLT), a region that is now the subject of increasing scrutiny. Continued operation of the Davis MF radar at a time of increased observation of the MLT from the ground and space allows investigations of dynamical coupling to continue in greater detail than has previously been possible.
MF radars measure winds in the MLT (~50-110 km) with good height and time resolution. Their ability to run continuously makes them ideal instruments to undertake long-term studies of the meteorology and climate in this region. This project will build on the highly successful program we have already undertaken to study the dynamics of the polar MLT by combining observations with the network of radars that has developed in Antarctica in the past decade. Upgrades and additions to MF radars at other Antarctic sites (Syowa, Rothera, Halley Bay and Scott Base) provide a radar network that rivals that now available in the Arctic. We propose to continue and extend this internationally collaborative research.
The past decade has also seen a significant increase in the scientific infrastructure to study the MLT at Davis itself. We propose to use this expanded instrumentation to make studies on a local scale that have not previously been possible. These new investigations will complement the observations made with the planned Syowa MST radar, with radar networks in the Antarctic and Arctic and with satellite studies of the polar MLT.
Taken from the 2008-2009 Progress Report:
Progress against objectives:
Combining observations from radars in the Antarctic MF radar network:
With the aid of radars at four Antarctic stations, a study has been carried out that relates short-time scale variations in the global wave field to the semidurnal tide above Antarctica. Modelling and theoretical studies suggest that Westward propagating wave one (W1) and wave 3 (W3) tidal products could be produced through interactions between the migrating (Westward wave 2) semidiurnal tide and planetary waves in the northern stratosphere. This study has verified these predictions by identifying both W1 and W3 source regions, and has explained their differing latitudinal extent.
Tidal results from the four Antarctic MF radars have also contributed to space-based studies of the polar mesosphere. The Aeronomy of Ice in the Mesosphere (AIM) project makes observations of mesospheric ice clouds at almost the same local time each day. Our tidal results have provided insight into the dynamical state of the atmosphere around their observations. These data have been provided for presentation at recent AIM working group meetings.
Contributed to experiments carried out using other infrastructure at Davis and beyond:
The Davis MF radar is able to provide excellent information on the state of the winds in the mesosphere and lower thermosphere. These have made significant contributions to studies of Polar Mesosphere Summer Echoes (PMSE) carried out by our collaborators using the Davis MST radar.
A study of a proposed interhemispheric coupling mechanism is underway. This compares the modulating effect of the global planetary wave field to a response in the summer MLT.
Davis MF radar winds continue to be provided to the NASA TIMED satellite mission through the ground-based instrument part of that project.
This project has contributed to six category one publications in the 2008/2009 year.