HF Radar data availability and measurement accuracy in Liverpool Bay before and after the construction of Rhyl-Flats wind farm

Abstract

High Frequency (HF) radar deployments are essential components of coastal monitoring systems. The accuracy of the measurements can be compromised if there are significant non-wave targets (e.g. ships or wind turbines) in the field of view. Liverpool Bay, on the North West coast of England and Wales, is an area of significant wind farm development and was the site of a HF radar. This was deployed as part of the Liverpool Bay coastal observatory to provide measurements for model development and testing. In this paper the HF radar current and wave measurements are compared with co-located in-situ measurement devices and with data at the Rhyl-Flats wind farm. The three month period in 2009 and 2010 is intended to give a clear picture of radar performance before and after the wind farm installation.HF radar and Acoustic Doppler Current Profiler (ADCP) current measurements are found to highly agree before and after the wind turbine construction with correlations >0.9. Wave measurements at the wind farm site show agreement between the HF radar cells and buoy data to be close to the average in 2009 and below the average in 2010 with the wind turbines introducing spurious wave measurements particularly in low sea conditions.