On wave radar measurement

Abstract

The SAAB REX WaveRadar sensor is widely used for platform-based wave measurement systems by the offshore oil and gas industry. It offers in situ surface elevation wave measurements at relatively low operational costs. Furthermore, there is adequate flexibility in sampling rates, allowing in principle sampling frequencies from 1 to 10 Hz, but with an angular microwave beam width of 10° and an implied ocean surface footprint in the order of metres, significant limitations on the spatial and temporal resolution might be expected. Indeed there are reports that the accuracy of the measurements from wave radars may not be as good as expected. We review the functionality of a WaveRadar using numerical simulations to better understand how WaveRadar estimates compare with known surface elevations. In addition, we review recent field measurements made with a WaveRadar set at the maximum sampling frequency, in the light of the expected functionality and the numerical simulations, and we include inter-comparisons between SAAB radars and buoy measurements for locations in the North Sea.

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Acknowledgments

The work described in this paper would not have been possible without the assistance of staff from Emerson, who made time available to meet with one of us in Linköping for open discussion on the functionality of the WaveRadar; and in particular, we would like to thank Hakan Bertling and Jan Westerling for providing additional information and responding to further questions following the meeting.

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Correspondence to Kevin Ewans.

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This article is part of the Topical Collection on the 13th International Workshop on Wave Hindcasting and Forecasting in Banff, Alberta, Canada October 27 - November 1, 2013

Responsible Editor: Val Swail

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Ewans, K., Feld, G. & Jonathan, P. On wave radar measurement. Ocean Dynamics 64, 1281–1303 (2014). https://doi.org/10.1007/s10236-014-0742-5

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Keywords

  • Wave measurement
  • Wave radar
  • Inter-comparison
  • Surface elevation
  • Wave spectra