AN ANALYSIS OF WINDS AT SYDNEY-KINGSFORD-SMITH-AIRPORT

The measurement of wind speed and direction is sensitive to local infl uences and when undertaking analyses based on these data over long per iods it is essential that an assessment is made of the impact of any i nstrument changes, instrument bias and changes in the location or expo sure of the anemometer, This has become significantly more important w ith the increasing use of meteorological data in environmental studies to support costly development projects, In this study, the climatic w ind record for Sydney Kingsford Smith Airport for the period 1940-1995 is examined and previously unrecognised data quality concerns are ide ntified. The anemometer has been replaced and relocated in this period , there have been changes in the exposure at the anemometer site resul ting from development on the airport, and the wind speed was under-rep orted for an extended period due to an instrument bias. We determine t he magnitude of the instrument bias and the impact of exposure changes resulting from development on the airport and site changes, Calculati on of this latter component is based on the classic logarithmic wind p rofile in the surface layer, a subjective estimate of the change in ef fective surface roughness length and the assumption that winds represe ntative of an 'open flat terrain' are required, The analysis provides some progress towards the development of a reliable and homogeneous cl imatological wind record.