Tidal Anomalies

The gravitational force of the sun and the moon on the earth generate ocean tides. The moon has the greatest effect and larger tides occur at times of a new or full moon.

Ocean tides are modified by meteorological conditions or weather patterns. Two important factors in modifying predicted tides are the passing overhead of atmospheric pressure systems (highs or lows) or the presence of storm conditions.

As it is difficult to predict the meteorological components of tides accurately, measurements are taken at selected NSW locations as the tidal record for that part of the coast. By comparing the predicted tidal data to the actual tide measured it possible to show the differences caused by the weather patterns. These differences are known as anomalies or the residual and are important data in determining the 'worst case' conditions for coastal, environmental and structural design purposes.