The National Science Foundation's Office of Polar Programs places automatic weather station (AWS) units in remote areas on Antarctica in support of meteorological research and operations.
The basic AWS units measure air temperature, wind speed, and wind direction at a nominal height of 3 meters above the surface. Air pressure is measured at the height of the electronics enclosure. Some units measure relative humidity at 3 meters above the surface and the air temperature difference between 3 meters and 0.5 meters above the surface at the time of installation. The data are collected by the ARGOS Data Collection System on board the National Oceanic and Atmospheric Administration series of polar-orbiting satellites.
The table gives the AWS unit's site name, ARGOS identification number, latitude, longitude, elevation above sea level, site start date, and WMO number for the Global Telecommunications System for AWS units in operation in 1995. The AWS units are grouped together based on area and are usually related to a single meteorological experiment. Stearns and Weidner (1992) and Holmes, et al (1993) describe the AWS activities during the two previous austral summers.
The AWS units are located in arrays for meteorological experiments and at other sites for operational purposes. Any one AWS may contribute to several experiments and all contribute to operational purposes, especially for preparing weather forecasts for aircraft flights to and from New Zealand and within Antarctica.
Some of the areas supported are:
The 1993-1994 Antarctic field season started on 29 December 1993 when G.A. Weidner, M. Seefeldt, J. Cassano, and R.E. Holmes left Madison, Wisconsin for McMurdo, Antarctica, arriving on 4 January 1994.
A USCG helicopter flight was made to Minna Bluff site on 8 January 1994. The aerovane had broken off at the mast, and was found on the surface next to the station. The antenna was also damaged. AWS 8915 was removed and the aerovane and antenna were returned to McMurdo for repair.
Willie Field and Pegasus North sites were visited using a USCG helicopter on 10 January 1994. AWS 8927 and the aerovane were removed from Pegasus North and returned to McMurdo for repair. AWS 8901 was also removed from Willie Field and returned to McMurdo for repair.
A USCG helicopter flight was made to Linda site on 11 January 1994. AWS 8915 was replaced with AWS 8909.
A second USCG helicopter flight was made to Minna Bluff site on 12 January 1994. AWS 8988 was installed with a new antenna and an R.M. Young wind system.
On 13 January 1994, Marilyn and Schwerdtfeger sites were visited using the Twin Otter aircraft. Marilyn site was in good condition. The lower vertical temperature difference sensor was raised to 1 meter above the snow surface and two boxes of three 40 amp hr batteries were also installed. The malfunctioning aerovane at Schwerdtfeger site was replaced.
A second USCG helicopter flight was made to Pegasus North site on 14 January 1994. AWS 8927 was reinstalled. The existing 1.8 m length boom was replaced with a 0.9 m length boom and a new R.M. Young wind system was installed. The solar panel and power junction box were replaced with new components, and the lower vertical temperature difference sensor was raised to a height of 1 meter. One box of three 40 amp hr gel cell batteries was also installed.
A Twin Otter flight was made to Lettau site on 17 January 1994. One 1.5 m tower section was added to the station. A new antenna and another aerovane were also installed. Two new boxes of three 40 amp hr batteries were installed as well.
Willie Field site was revisited by truck on 18 January 1994. AWS 8901 was reinstalled. A Campbell Scientific CR-10 data logger with an Ultrasonic Depth Gauge was installed in support of S-186. The lower vertical temperature difference sensor was raised to a height of 0.7 m. An R.M. Young wind system was also installed.
An LC-130 flight was taken to Byrd Surface Camp on 21 January 1994. The trip from Byrd Surface Camp to Byrd site was made by snowmobile. The existing 1.8 m length boom was replaced with a new 0.9 m length boom. The existing antenna was unusable, and another antenna was shipped to Byrd Surface Camp and installed by camp personnel on 30 January 1994.
The wind speed sensor was questionable at Marble Point site. On 22 January, a USCG helicopter flight was made to the site. A replacement aerovane was installed and the wind speed sensor output appeared to be fine.
Mount Howe, Kelly, and Lindsay sites were visited by Twin Otter on 22 January 1994. The station at Mount Howe had sustained severe damage from wind and the ice around the anchors and tower base had ablated so that the tower was no longer anchored sufficiently. Mount Howe site was removed, as were Kelly and Lindsay, which had been installed in support of S-203.
Clean Air site was moved from it's previous location to one approximately 30 meters from the South Pole Meteorological tower on 24 January 1994. AWS 8918 was replaced with AWS 8987. A snow temperature profile was also added. The depth of the profile extends to 4 meters.
An attempt was made to visit Gill site by Twin Otter on 27 January 1994. We were unable to land due to low clouds and fog. The clouds and fog remained in the area during the following day and the flight was scrubbed.
In early March, crew members of the USCG ice breaker Polar Sea flew by helicopter to Whitlock site and replaced AWS 8925 with AWS 8921.
Near the Adeile Coast, members of Expeditions Polaires Francaises visited D-80 Site on 1 February 1994. Two 1.9 meter tower sections were added, as were two boxes of three 40 amp hr batteries. A new sensor boom and aerovane were installed as well. They replaced the existing electronics with a new unit. The ARGOS ID of 8919 was unchanged, however new pressure calibration data will be provided. Also, AWS 8916 at D-47 was removed and returned to Madison for repair.
On the Antarctic Peninsula, members of the British Antarctic Survey serviced several AWS units during the austral summer. AWS 8917 was installed at Sky-Hi site in mid February. AWS 8932 was installed at Recovery Glacier. Butler Island (AWS 8902) was serviced and two 1.9 meter tower sections were added to Uranus Glacier site. Larsen Ice Shelf site will be serviced at a later date if possible.
Members of the Japanese Antarctic Research Expedition were responsible for the installation of an AWS unit at their intermediate camp. At this time, no report of their progress has been received.
The automatic weather station program is supported by National Science Foundation OPP 93-03569. The British Antarctic Survey installs and services the automatic weather stations in the Antarctic Peninsula area. Expeditions Polaires Francaises installs and services the units along the Adeile Coast. The Japanese Antarctic Research Expedition installs and services those units near the Prince Olav Coast.
We were assisted at McMurdo by NSFA-Meteorology, Byrd Surface Camp personnel, and the crews of the Twin Otters, USCG helicopters, and the LC-130's.
References
Stearns, C.R. and G.A. Weidner. 1992. Antarctic automatic weather stations: Austral Summer 1991-1992, Antarctic Journal of the U.S., XXVII(5), 280-282.
Holmes, R.E., G.A. Weidner, and C.R. Stearns. 1993. Antarctic automatic weather stations: Austral Summer 1992-1993, accepted by Antarctic Journal of the U.S., XXVIII(5).