Imaging Radar for the Nearshore

Wave Analysis with Radar

larger image
Top: Portions of single radar images expanded to show the area near Benson Beach, WA. Waves were consistently breaking as far out as 1 km from shore leading to the bright radar returns as far out as the end of the north jetty.
Bottom: Frequency spectra calculated from radar pixel time series located approximately 600 m offshore of Benson Beach. Estimated peak periods are compared with those measured by NDBC Buoy 46029 located xxx.

The flow out of the Columbia River varies depending on the stage of the tide and during periods of strong currents the wave field can be significantly modified. For example, during strong ebb flows waves over the Columbia River Bar are highly steepened and often break, which leads to dangerous navigational conditions.

Jan 18 Mid-tide Left: Radar image taken Jan 18th during a mid-tide condition when currents were not strong shows little breaking offshore.
Jan 18 strong ebb tide Left: Radar image taken on Jan 18th at 705PM during a strong ebb tide current shows a strong increase in wave breaking just offshore of the river mouth.