Note: Time is in UTC (PST -8/PDT -7).

Currents: Point Reyes to Bodega Bay

This map shows the hourly direction and speed of sea surface currents at intervals of 2km.

The data are calculated by combining radar measurements from two shoreline stations, one at Bodega Bay and the other at Point Reyes National Seashore.

Currents: Point Arena to Bodega Bay

This long-range map shows the hourly direction and speed of sea surface currents at intervals of 6km.

The data are calculated by combining radar measurements from two shoreline stations, one at Bodega Bay and the other at Point Arena, Mendocino County.

Sea surface current research products >

HF Radar Derived Wave Height and Direction- Bodega Bay, CA

Note: the date/time axis in these charts is in UTC (PST -8/PDT -7).

Wave height is in meters, measurements are ~ 2-18 km (~1-11 miles) offshore.

Additional wave information:

• Northern California Wave Data Humboldt Bay to Point Conception.
• Coastal Data Information Program Swell Height Ano Nuevo to Point Arena

Looped movie file of the last week's sea surface currents (20 MB .mpg file)

Note: Time is in UTC (PST -8/PDT -7).

Google Map Interface to HFRADAR Derived Surface Currents Nationally

High Frequency Radar: Sea Surface Current and Wave Sensors

Instrument Type: CODAR Ocean Sensors SeaSonde HF Radar System

Description: High-frequency (HF) radar uses radio-wave backscatter to map surface currents over wide swaths of the coastal ocean. These sensors are commonly referred to by the trade name "CODAR" (Coastal Ocean Dynamics Applications Radar) and take advantage of the propagation of radio waves over large distances out and back across the surface of the conducting sea water, and they have resonant interactions with ocean surface waves (i.e., the ones that can make people seasick). Back at the shoreline, a measurement of the frequency offset (i.e., Doppler shift) of the reflected radio waves provides a remotely sensed measurement of the speed of the ocean waves and surface currents.

Locations:

5 MHz - Bodega Marine Laboratory: 38° 19' 10.1" N 123° 4' 25.0" W - Installed: 2 February 2007
5 MHz - Point Arena: 38° 55' 42.4" N 123° 43' 40.0" W - Installed: 16 June 2007
12 MHz - Bodega Marine Laboratory: 38° 19' 2.3" N 123° 4' 20.9" W - Installed: May 2001
12 MHz - Point Reyes: 38° 2' 49.7" N 122° 59' 20.9" W - Installed: June 2001
12 MHz - Salt Point State Park: 38° 34' 0.5" N 123° 19' 53.7" W - Installed: 2002

12 MHz Specifications - Surface currents:

Map spatial resolution: 2 x 2 km
Map temporal interval: hourly; currents averaged over one hour
Map area coverage: 65 km along shore x 30 km offshore, variable
Map vector accuracies: speed < 7 cm/s, direction < 10°

Specifications - Waves:

Target range: 3 km from coast around each radar
Significant wave height accuracy: 7 to 15%
Dominant on-shore direction accuracy: 5° to 12°
Dominant wave period accuracy: 0.6 s
Minimum detectable significant wave height: 1 m
Wave temporal interval: hourly; waves averaged over one hour

Specifications - Radiated signal:

Output radiated power: 80 watts peak, 40 watts average
Operating frequency range: 12-14 MHz

Matlab/HFR Progs Compatible QA/QC Scripts

BML HFR Progs Supplement: Matlab routines to calculate temporal and spatial statistics for HF radar data, and perform QA/QC on the data.

The statistics are described in the following paper: Quality Control of HF Radar Measurements: Temporal and “Nearest Neighbor” Spatial Statistics, by Chris Halle, submitted August 2008. Please reference the paper and/or acknowledge this website if using these routines or statistics.

TO DOWNLOAD: PC: right click on file name > save target as…
Mac: option click on file name to download…

SampleStatsScripts.zip: Scripts that calculate the statistics and qa/qc the radials and totals.  Script names generally follow the naming convention:  (1) scripts starting with “Get” – calculate the statistics, (2) script starting with “Clean” – qa/qc the radials or totals using the previously calculated statistics and user-specified totals, and (3) scripts starting with “Inv” – use the previously calculates stats and allow the user to interactively investigate the effects of setting different screening levels for the statistics.

SampleDrivingScripts.zip: Samples of scripts that call the stats routines in the folder SampleStatsScripts.

SampleUsefulScripts.zip: Miscellaneous useful scripts.

Current Rose Routines for HFR Data (HFRosePlotRoutines.zip): Prompt driven routines that allow the user to specify the date search range, etc, and generate plots similar to this sample plot.

Driving routines to begin with:

Radial QA/QC:

• GenericGetRadialStats  (can run GenericPlotRadialStats to plot the stats up)
• GenericFirstOrderCleanRadials
• GenericSecOrderRadialStatsClean

Totals QA/QC:

• GenericLRTotalsPartA(unfinished)
• Subsequent routines to be included

Stats Summaries:

• SummaryOfRadialCleaning.m contains parameters to clean radials
• SummaryOfTotalCleaning.m contains parameters to clean totals

Questions, comments or suggestions can be directed to the author, Chris Halle.

HFR_Progs Matlab Toolbox

High Frequency Radar Sea Surface Current Data

• For data requests please contact bmldata@ucdavis.edu, and see the data disclaimer and terms of use.
• Oceanography, Surface Currents, Matlab Scripts: Chris Halle, John Largier
• Radar Operation, Maintenance, Website: Deedee Shideler
• Radar Operation, Maintenance, Progamming: Marcel Losekoot