1. Validation of a high-resolution (400m) SAR motion tracking system near the APLIS’07 Ice Camp M. Thomas, C. A. Geiger and C. Kambhamettu

2. Roadmap We successfully implemented a “near real time” sea ice motion tracking system  Measure motion dynamics at ~400m resolution  Logistical aid to deploy 12 GPS (strain-rate) buoys, 1 ice mass balance buoy and 5 stress buoys. High regions of activity in the 200km x 200km region Used to setup the data collection location for AUVs and human divers  http://vims.cis.udel.edu/~mani/SEDNA - The “Map of Moving Topography” (MMT) http://vims.cis.udel.edu/~mani/SEDNA This talk discusses the initial validation of the system against GPS and ARGOS.

3. VIMS 12 VIMS 11 National Ice Center GPS Buoys Field Scientists Analysis @ UD vims.cis.udel.edu X ©CSA1998 Alaska Satellite Facility System Overview

4. Toggle

7. GIS Data Layering Scheme Data visualization done in Matlab

9. Instrument measurements (Buoy 74357) Buoy data from Jenny Hutchings’ SEDNA buoy array

10. Validation against GPS North-South displacement East-West displacement Error in North-South displacement Error in East-West displacement

11. Validation against raw ARGOS East-West displacement North-South displacement Error in East-West displacement Error in North-South displacement

12. Validation against filtered ARGOS East-West displacement North-South displacement Error in East-West displacement Error in North-South displacement

13. One-way repeated measure ANOVA Dependent variable: Sea ice motion Independent variables: Motion Estimation, GPS, ARGOS, Filtered ARGOS Cross validations at the 12 GPS Buoy locations  Results indicate no significant difference between our algorithm with GPS, ARGOS and filtered ARGOS.  Scatter plot shows the high correlation between our estimated algorithm and GPS measurements

14. Significance tests LocationFdFpF p 10.2031.8020.7951.6151.6360.213 20.1101.2380.7950.4441.7890.622 30.8661.6340.4080.9391.1670.355 40.5591.5580.5340.1321.2210.769 50.5181.4110.5380.3181.6890.693 60.1141.6910.8611.5901.2780.220 71.3162.2600.277 1.8950.747 80.6542.2900.5440.3871.2700.588 90.3481.9890.7061.5501.5220.226 102.7621.6080.0850.3001.2240.634 110.2871.1370.6260.0781.3360.850 120.6251.4970.4960.2721.9430.757 Horizontal displacementVertical displacement F: statisticdF: degrees of FreedomP: – significance level (0.050)

15. Sample East-West Directions

16. Sample North-South Directions

17. Conclusions Motion tracking algorithm is within the accuracy of the GPS data (mean vector difference 0.06 cm/s) Specifically, ANOVA technique cross validates the accuracy of the repeated measurements at the 12 locations. Estimation Resolution:  Motion can be estimated at ~400 meters resolution, an order of magnitude higher than typically available techniques. Computational Requirements:  Images pairs of 200km x 200km (4096 x 4096 pixels) can be processed in under 20 minutes on a 2.93 GHz Core 2 Duo Processor PC.

18. Future directions Developing mechanisms to handle discontinuities from within the motion estimation framework. Development of a open source code initiative that could be used by researchers for sea ice monitoring. Web based framework for remote analysis of imagery for researchers.

19. Acknowledgements We would like to thank our sponsor without whom this would not have been achieved  NSF Arctic Natural Science within the Office of Polar Programs (ARC-0612105 (UD), ARC-0612527 (UAF), and ARC-0611991 (CRREL)). We would also like to thank the Canadian Space Agency (CSA), who provided the RADARSAT-1 imagery through ASF. Thank You!!!