The Physics & Astronomy Department of the Univsersity
of Canterbury used to operate an ionosonde at both Eyrewell (about 30km northwest of
Unfortunately the LandCorp site at Eyrewell was converted to a large diary farm in early 2014 shortly after the instrument had been replaced with a state of the art CADI system. Once a new site is secured it is envisaged that New Zealand will again have a ground based method of detemining the local ionospheric conditions essential for some remote search and rescue missions. Currently the closest ionosonde is in Australia leaving all of NZ, and it's vast surrounding oceans reliant on model output.
An ionosonde is a swept frequency vertical sounding radar. The time delay of the echoes from the ionosphere give information on the electron density in the ionosphere. The ionogram (picture produced by an ionosonde) displays the time to receipt of an echo on the vertical axis against frequency on the horizontal axis. Ionograms are recorded typically every 5 minutes for good temporal resolution.
Ionosondes are operated at several locations by IPS in Australia. IPS, a unit of the Australian Government Bureau of Meteorology, provides the Australian radio propagation and space environment services. Current and recent ionograms for all automated sites may be viewed using the Java applet provided on the IPS site. Data archives on film dating from the earliest ionosonde in 1938 until the early 1990’s are held at the New Zealand Film Archives unit.
The remaining Scott Base ionosonde
is maintained under an IPS contract to the Department of
Physics.