Radars map atmospheric phenomena

A second high frequency Tasman International Geospace Environment Radar (TIGER) was commissioned this February at Awarua near Invercargill, New Zealand. The radar, named ‘Unwin’ after New Zealand scientist Dr Bob Unwin — a pioneer in auroral radar development — will operate in tandem with the original radar established on Bruny Island, Tasmania, in 1999 (Australian Antarctic Magazine 1:27–28). Together, they will map the motions of aurora, meteors and ocean waves in the southern hemisphere.

TIGER operates as a stand-alone dual radar system, but is also part of the international Super Dual Auroral Radar Network, operated by ten nations, which covers southern and northern polar atmosphere regions. The radars survey the ionosphere, 100–300km above the Earth, to provide measurements of the aurora australis and other phenomena. The information they provide will improve our knowledge of space weather processes, allowing us to better manage radio communications, navigation systems, satellite operations and magnetic mineral surveys. The radars can also derive ocean wave motion from backscattered sea echoes and detect echoes from meteors, which are used to calculate wind speeds at heights around 100km.

TIGER is operated by a consortium of Australian research institutes headed by La Trobe University and including Monash University, University of Newcastle, AAD, IPS Radio & Space Services, British Antarctic Survey and the Defence Science and Technology Organisation.

Ray Morris, Ice, Oceans, Atmosphere and Climate Programme, AAD
Peter Dyson, Department of Physics, La Trobe University