23 Aug 2017 –
Peak virtual height maps of the F2-layer (h’F2) have been removed from the website (they were at the bottom of http://www.sws.bom.gov.au/HF_Systems/1/4). Virtual height is determined from the time required for the radiowave to travel to the ionospheric layer, assuming that the wave is propagating at the speed of light. For instance, an ionogram shows a series of transmitted radiowave frequencies and the virtual height at the reflection point, if any, of these frequencies. Using modelling techniques, the frequency vs virtual height profile of the ionosphere can be converted to a frequency vs true height profile. It has therefore been decided that the virtual heights (h’F2) maps will be replaced by the true height maps of the F2-layer (hmF2) on the website. An update will be provided once this has been accomplished.
09 Feb 2016 –
Revised online HF and Digital HF prediction tools are now available. These tools are designed for modern browsers (IE 10 or later, Firefox, Chrome, etc). The old tools will be retained for one month. Please report any issues via our feedback form Regards Space Weather Services
04 Jun 2014 –
The Christchurch Ionosonde located at Eyrewell has been decommissioned and put into storage for redeployment at a new site in the region.