History of Casey Meteorological Office

Casey Meteorological Office

Casey and the surrounding area has had three bases in its brief history 1957 to 2004. During that time temporary settlements during summer were established at S1, S2 and Law dome for ice core movement and ice sampling. Also temporary settlements on off shore islands over summer, like Ardery Island, were in place studying penguin and sea bird life. Meteorology as always been a key input to all scientific studies and in support of all forms of transport, travel and trade activities. The Bureau of Meteorology has had a representative at Wilkes to the current day at Casey and has contributed to the understanding of the weather around the Casey area.

Wilkes base was established in USA 1957 for the International Geophysical Year (IGY). It is 1.5km north from the current Casey station across Newcomb Bay. Meteorological equipment included Metox and valve radio sondes. There were two ways of generating Hydrogen, primarily with the use of the Hydroneal which used Ammonia heated in a furnace to split Nitrogen and hydrogen. The back up method was by a chemical mix of caustic soda and ferro silicate with water in a high pressure vessel to produce hydrogen for the Met balloons. Wilkes was formally handed over to Antarctic Division by the Americans. Wilkes was then occupied by Australian National Antarctic Research Expeditions (ANARE) from 1960 to 1969, when encroaching snow melt forced its abandonment. During the latter period trades people would travel from Wilkes to REPSTAT (REPlacement STATion). This was the name used prior to the formal naming of Casey station - after Governor General Lord Casey.

The first Casey Station (est. 1969) also know as "The Tunnel", has since been the site of regular surface and upper air weather observations. It was a long "D" shaped corridor with container rooms separately connected along the corridor, whose length was about 200m. The whole structure was elevated above the ground some 2m. There was a complement of 5 staff - four observers and a Technician. The program consisted of two combined sonde and radar flights plus one wind finding flight. The Hydroneal and high pressure chemical equipment were transferred to the new station and operated for the life of the station. The chemical generation was phased out in the 1970s leaving the Hydroneal as the primary Hydrogen source. A wind finding Plessey WF2 radar was installed on a rocky knoll at the northern end of the station, housed in a 14m fibreglass dome. In 1977 this dome was blown apart by a blizzard with peak gust of 153 knots. The radar operated out in the open until change over at the end of the year. The radar had replaced the Metox. The radio sonde equipment was upgraded in the 1980s to transistor based sonde and receiving equipment. The surface instrumentation was automated to paper recorders using a Fielden temperature transmitter, while the wind Bendix Aerovane used a Selsyn servo system to drive the recorder. The balloon building was elevated, to overcome the problem experienced at Wilkes of being buried by snow and melt. The balloon inflation building contained a static ioniser nozzle using air passing over a Polonium strip to produce large amounts of +/- charged particles, which reduce the static around the inflated balloon in the dry Antarctic atmosphere. At the end of the Tunnel Met Office DigiCORA was introduced as a trial, against the radar. This used the VLF Omega signal as a method of calculating the winds. The structure of the tunnel suffered from foundation rust and ice in the wall panel. In 1987 work commenced to replace the foundation structure, however this proved too big a task and a decision was taken to move and rebuild on a hill 1km to the South. Trades people travelled from the Tunnel to the new site from 1986 until about 1989 when the station was moved. With the introduction of DigiCORA, the Observation program was cut back as it performed both upper air temps/pressure and winds so one operator was required. Consequently two Observers and a Technician were required.

In 1989 most of the new sophisticated buildings at Casey were completed. Other buildings completed later were the science and workshop areas. The Met Office commenced using the DigiCORA with mixed results as not all Omega stations were received giving poor wind performance for many years. The WF2 radar was moved to the new site and was used in the first year or so as a back up to the DigiCORA. The Hydrogen used in the Met balloons was produced from a new Stuart Electrolyser, this reduced the safety risks involved with producing Hydrogen, and automated the process. The humidity was added to the suite of recording sensors with a Vaisala humidity transmitter installed in the Stevenson screen. In the early 1990s the AVHRR Satellite receiver was installed. In 1991 the first remote Automatic Weather Station (AWS) was installed for the Australian Antarctic Division (AAD) aviation transport program near Lanyon Junction. It was installed on the WF2 radar site, which was no longer required due to some improvements to the DigiCORA. Communications took off with the introduction of a Land Sat station. In the next years the Met office had its own 64kbps comms link to the Bureau's HO. The Met Office building was enlarged in 1993 to encompass the Antarctic Meteorological Centre (AMC). The AMC was staffed from 1994 till 1999 with 2 Meteorologists during the summer period. The computing hardware went from a single IBM server with SCSI interface to and a full Australian Integrated Forecast System (AIFS) and local area network (LAN) over the operating years. In 1994 a MicroMac AWS was installed, replacing the discrete surface instrumentation chart recorders. In 1994 three Steedman AWS were installed at Haupt Nunatak, Balaena Is. and Snyder Rocks. These had technology difficulties and were removed in 1998. Over the next 6 years some of these were replaced and other sites developed with the anticipated intra continental flying program. In all there are 8 AAD Series type AWS installed around the Casey and Law Dome area, sending their messages via ARGOS satellites. In late 1990s the DigiCORA was upgraded to be capable of receiving GPS sondes, improving the performance over the previous Omega system. Casey Met. now have a Virtual Private Network (VPN) running under TCP/IP to connect into the Bureau's communication WeatherNet..

Future developments for Casey include:

• upgrading the AVHRR with a digital satellite receiver
• upgrading DigiCORA I to DigiCORA III
• upgrading the MicroMac AWS to Almos AWS
• replacing the Stuart Electrolyser with a Hogen H2 generator.

The AMC is expected to be re-staffed and the AIFS forecasting equipment to be reinstalled, along with an upgrade of the LAN.