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John Turner, Stephen Pendlebury, Lance Cowled, Kieran Jacka, Marjorie Jones, and Philip Targett

The First International Symposium on Operational Weather Forecasting in Antarctica was held in Hobart, Australia, from 31 August to 3 September 1998. There were 40 attendees at the meeting from Australia, Belgium, Brazil, China, France, Italy, Russia, and the United Kingdom. In recent years there has been considerable growth in the requirement for weather forecasts for the Antarctic because of the increases in complex scientific research activities and the rapid growth of tourism to the continent. At many of the research stations there are now sophisticated forecasting operations that make use of the data available from drifting buoys and automatic weather stations, the output from numerical weather prediction systems, and high resolution satellite imagery. The models have considerable success at predicting the synoptic-scale depressions that occur over the ocean and in the coastal region. However, the many mesoscale systems that occur, which are very important for forecasting local conditions, are not well represented in the model fields and their movement is mainly predicted via the satellite data. In the future it is anticipated that high resolution, limited-area models will be run for selected parts of the continent. The symposium showed that great advances had been made during recent years in forecasting for the Antarctic as a result of our better understanding of atmospheric processes at high latitudes, along with the availability of high resolution satellite imagery and the output of numerical models. Outstanding problems include the difficulty of getting all of the observations to the main analysis centers outside the Antarctic in a timely fashion, the lack of upper air data from the Antarctic Peninsula and the interior of the continent, and the poor representation of the Antarctic orography and high latitude processes in numerical models. An outcome of the symposium will be a weather forecasting handbook dealing with the entire continent.

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Hugh A. Hutchinson, T. Stephen Dixon, Neil Adams, Kieran Jacka, Stephen F. Pendlebury, Lawrence Marsh, Lance H. Cowled, Henry R. Phillpot, Michael J. Pook, and John Turner

Abstract

An overview is presented of the analysis procedures and problems encountered in the FROST reanalysis of weather charts poleward of latitude 50°S carried out in Hobart by the Australian Bureau of Meteorology, with advice from the Institute of Antarctic and Southern Ocean Studies. A summary of findings as a result of the FROST exercise is given and some topics for research projects in the future are identified.

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John Turner, David Bromwich, Steven Colwell, Stephen Dixon, Tim Gibson, Terry Hart, Günther Heinemann, Hugh Hutchinson, Kieran Jacka, Steven Leonard, Michael Lieder, Lawrie Marsh, Stephen Pendlebury, Henry Phillpot, Mike Pook, and Ian Simmonds

An account is given of the Antarctic First Regional Observing Study of the Troposphere (FROST) project, which has been organized by the Physics and Chemistry of the Atmosphere Group of the Scientific Committee on Antarctic Research. The goals of FROST are to study the meteorology of the Antarctic, to determine the strengths and weaknesses of operational analyses and forecasts over the continent and in the surrounding ocean areas, and to assess the value of new forms of satellite data that are becoming available. FROST is based around three one-month Special Observing Periods (SOPs)—July 1994, 16 October–15 November 1994, and January 1995 for which comprehensive datasets have been established of model fields and in situ and satellite observations. High quality manual surface and upper-air analyses are being prepared for these periods to determine the extent to which non–Global Telecommunications System data can improve the interpretation of the synoptic situation. Over the ocean areas during SOP-1, incorporation of the late data resulted only in a limited improvement in the analyses, indicating that the models are correctly analyzing most of the major weather systems. Over the continent, the production of 500-hPa heights from the automatic weather station data greatly helped in the analysis process. The lack of data around west Antarctica was a major handicap in the analysis process. The rms errors in the forecasts of 500-hPa height for the Antarctic were about 20% greater than those for midlatitude areas. The forecasts from the European Centre for Medium-Range Weather Forecasts were the most accurate of those received.

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