1 / 38

Improving HF Radar Surface Current Measurements with Measured Antenna Beam Patterns

This research study by Josh Kohut and Scott Glenn explores how the accuracy of HF radar surface current measurements can be improved by calibrating data with measured antenna beam patterns. The study also examines the influence of horizontal and vertical shear on HF radar and ADCP measurements.

castaneda
Download Presentation

Improving HF Radar Surface Current Measurements with Measured Antenna Beam Patterns

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Recent Results from the HF Radar Network For NJSOS & NEOS Josh Kohut & Hugh Roarty Scott Glenn, Oscar Schofield & Many Others Coastal Ocean Observation Lab (COOL)Institute of Marine and Coastal Sciences (IMCS)Rutgers University Research http://marine.rutgers.edu/cool Education http://coolclassroom.org Public Outreach http://www.thecoolroom.org

  2. Loveladies, NJ New Jersey Installations Brant Beach, NJ USCG LSU Wildwood, NJ

  3. Number of Radial Current Vectors 1998 1999 2000 2001 2002 2003

  4. Ideal (not typical) Setup : Nantucket , MA Transmit Antenna Receive Antenna 50 meters

  5. 2001 Summer Experiment Tuckerton 5 MHz Long-Range CODAR COOL 1 COOL 2 • Long-Range and Standard CODAR • Thermistors at all 5 locations, spaced at 1 m intervals • ADCP • 1 meter bins • Continuously sampled every 5 s • 3 hour Centered Average COOL 3 Brigantine 25 MHz Standard CODAR COOL 4 COOL 5

  6. Tuckerton COOL 1 COOL 2 COOL 3 Brigantine COOL 4 COOL 5

  7. Improving HF Radar Surface Current Measurements with Measured Antenna Beam Patterns Josh Kohut and Scott Glenn - J. Atmos. Ocean. Tech., 20, 1303-1316. • The local environment plays a significant role in pattern distortion. • System accuracy improves when the data is calibrated wit the measured pattern. • When MUSIC uses the measured pattern, velocity vectors are more consistently put in the correct angular bin.

  8. Ideal Pattern, 8.27 cm/s RMS Difference Measured Pattern, 7.10 cm/s RMS Difference

  9. RMS Difference 3.92 cm/s RMS Difference 6.30 cm/s

  10. Intercomparison of an ADCP, Standard and Long-Range High-Frequency Radar: Influence of Horizontal and Vertical Shear Tuckerton COOL 1 COOL 2 Brigantine COOL 3 COOL 4 COOL 5 Hugh Roarty, Josh Kohut, and Scott Glenn • Use of Measured Antenna Patterns Improved Comparison • Decreased Vertical Shear due to Strong Stratification Led to Closer ADCP/HF Radar Comparisons • Differences Between ADCP and HF Radar Measurements are shown to Depend on the Strength of the Horizontal Shear

  11. 16 16 11 11 6 km Long-Range SeaSonde 2.5 m BIN 20 BIN 19 BIN 18 5 m BIN 17 12 m BIN 16 BIN 15 BIN 14 BIN 13 BIN 12 BIN 11 BIN 10 BIN 9 Bin 16 to 11, entire record RMS Difference = 7.2 cm/sec COOL 5 NTS

  12. Long-Range SeaSonde 2.5 m BIN 19 BIN 16 BIN 20 BIN 18 BIN 15 BIN 19 BIN 17 BIN 14 BIN 18 BIN 16 BIN 13 BIN 17 BIN 15 BIN 12 BIN 16 BIN 14 BIN 11 BIN 15 BIN 13 BIN 10 BIN 14 BIN 12 BIN 9 BIN 13 BIN 12 BIN 11 BIN 10 BIN 9 RMS Difference = 6.07 cm/sec COOL 4 COOL 3 COOL 5 4 km 4 km NTS

  13. CODAR/ADCP Comparisons Sorted by ADCP Horizontal Shear ADCP Bin 16 to 11 - RMS difference = 7.2 cm/s

  14. Temporal Variability of the ADCP RMS Differnece

  15. Cool 5 (Bin17) vs. Cool 5 ADCP Raw Velocity Tidal Velocity Bin RMS Bin RMS 1 3.4138 2 2.8113 3 2.2265 4 1.5252 5 0.71017 6 1.1287 7 1.2052 8 1.1467 9 1.0892 10 0.9149 11 0.7036 12 0.62108 13 0.70948 14 0.63184 15 0.52554 16 0.35932 17 0 18 1.7604 19 1.0081 20 2.2608 1 13.671 2 13.948 3 14.189 4 14.411 5 14.651 6 14.528 7 14.517 8 14.024 9 12.926 10 11.653 11 10.43 12 9.3549 13 7.9883 14 6.2468 15 4.4089 16 2.3032 17 0 18 4.7865 19 9.762 20 13.903 NP=122 NP=274

  16. Cool 5 (Bin17) vs. Cool 3 ADCP Raw Velocity Tidal Velocity Bin RMS Bin RMS 1 14.139 2 14.571 3 14.747 4 14.411 5 13.782 6 13.082 7 12.356 8 11.044 9 9.8501 10 8.6627 11 7.7062 12 6.7369 13 6.0721 14 5.3712 15 5.2163 16 10.577 17 14.852 18 21.666 19 17.594 20 17.602 1 4.7085 2 4.1243 3 3.3474 4 2.375 5 1.684 6 1.1125 7 0.68393 8 0.27787 9 0.37028 10 0.67474 11 0.96605 12 1.1827 13 1.218 14 1.1994 15 1.4759 16 2.7454 17 3.5908 18 2.4551 19 5.5286 20 5.4984 NP=122 NP=274

  17. CODAR vs. Cool 5 ADCP (2 pts required) Raw Velocity Tidal Velocity Bin RMS Bin RMS 1 12.725 2 12.863 3 13.086 4 13.318 5 13.619 6 13.344 7 13.169 8 13.261 9 12.626 10 11.055 11 9.8998 12 8.9065 13 8.1385 14 7.4351 15 6.8603 16 6.0464 17 5.8556 18 7.4992 19 10.791 20 13.82 1 3.5885 2 2.8348 3 2.0002 4 1.3733 5 1.5896 6 2.4228 7 2.7752 8 3.034 9 2.9855 10 2.373 11 1.8731 12 1.8667 13 1.9329 14 1.7496 15 1.511 16 1.1046 17 0.70644 18 1.3365 19 0.99657 20 2.1046 NP=82

  18. CODAR vs. Cool 5 ADCP (4 pts Required) Raw Velocity Tidal Velocity Bin RMS Bin RMS 1 12.655 2 13.016 3 13.597 4 14.117 5 14.733 6 13.214 7 12.082 8 12.357 9 12.364 10 9.4986 11 7.0517 12 6.0752 13 5.482 14 5.0995 15 4.8628 16 4.7105 17 5.1335 18 8.594 19 12.746 20 13.642 1 2.8037 2 1.6774 3 0.91105 4 0.74422 5 1.5933 6 3.8889 7 4.5 8 5.004 9 4.6983 10 2.807 11 1.3209 12 1.051 13 1.0825 14 1.0887 15 1.0014 16 0.80063 17 0.80789 18 3.5935 19 4.445 20 7.7683 NP=16

  19. July 28th to 30th: Low Shear August 1st to 3rd: High Shear

  20. Location of Bin 16 Location of Bin 11 Temperature °C

  21. RMS Difference – 3.0 cm/s

  22. RMS Difference – 2.78 cm/s

  23. Tuckerton COOL 1 COOL 2 Brigantine COOL 3 COOL 4 COOL 5 Horizontal Shear between COOL3-Bin 12 and COOL5-Bin 16 6.07 cm/sec Horizontal Shear between surrounding CODAR Bins 5.9 cm/s 7.6 cm/s Range Cell 4 5.7 cm/sec Angular Bin 230 7.2 cm/sec

  24. CODAR vs. Cool 5 ADCP (2 pts required) Raw Velocity Tidal Velocity Bin RMS Bin RMS 1 15.835 2 16.351 3 16.99 4 17.615 5 18.132 6 16.879 7 16.868 8 17.351 9 15.962 10 12.416 11 9.5592 12 8.0316 13 6.7406 14 5.7951 15 5.334 16 5.0007 17 4.9972 18 8.5758 19 11.451 20 12.07 1 7.3489 2 6.9643 3 6.7689 4 6.4861 5 6.1781 6 4.9769 7 4.3363 8 3.7274 9 3.3498 10 2.4513 11 1.7429 12 1.3899 13 0.8083 14 0.41202 15 0.29245 16 0.19996 17 0.36631 18 3.0764 19 1.4955 20 4.3031 NP= 25

  25. 1 hr Mean = 2.11 2 pt Mean = 4.14 4 pt Mean = 4.71

More Related