The Australasian geodetic Very Long Baseline Interferometry (VLBI) array consisting of three new 12-meter radio telescopes in Australia (Hobart, Katherine and Yarragadee), a 12-meter radio telescope in New Zealand (Warkworth) and a correlation facility in Perth started operations in 2011. The daily positions of the AuScope array are estimated with a precision of a few mm, whereas their daily estimates vary within a range of 20-30 mm on the annual scale. Analysis of geodetic VLBI sessions also reveals small linear trends in the time series of baseline lengths between the Australian and New Zealand stations. A seasonal signal with amplitude of about 10 mm was detected for the baseline Hobart--Katherine. This signal is consistent with seasonal variations of baselines between collocated GNSS stations. We argue this signal should be incorporated in the fitting model to improve the estimates of positions and linear velocities.
This paper was prepared for the 8th IVS General Meeting 2014, held in Shanghai, China, March 2–7, 2014.