Indian Mainland Coastal Product

• Version 1.1 (Beta)

• Altimeter Sensor-Interim Geophysical Data Record (S-IGDR)
• Indian Ocean Bathymetry
• Indian Ocean Geoid
• High resolution coastline

• i. High resolution bathymetry is used to separate the coastal and land waveforms.
• ii. Waveforms are classified based on their shape.
• iii. Waveforms are retracked with the beta parameter retrackers (BETA5 and BETA9) and BAGP (Brown with asymmetric Gaussian Peak) retracker to get sea surface height (SSH), sea surface height anomaly (SSHA), significant wave height (SWH) and wind speed.
• iv. Using Significant Wave Height (SWH) and wind speed, the wave period is derived based on the data adaptive technique of " Genetic Algorithm " (Remya et al. 2011)
• v. Wave power is derived based on SWH and estimated wave period. 40 Hz data is filtered using a lanczos filter to remove high frequency noise.
• vi. Wind power is calculated using standard wind power formula. 40 Hz data is filtered using a lanczos filter to remove high frequency noise.

• Amarouche L, Thibaut P, Zanife O.-Z, Dumont, P. Vincent J.-P. and Steunou N 2004. Improving the Jason-1 ground retracking to better account for attitude effects, Mar. Geod. 27: 171-197.
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• Satellite Altimetry and Earth Sciences, ed. L.L. Fu and A. Cazenave, pp. 1-131.
• Chaudhary A., Basu S., Kumar R, Mahesh, C. and Sharma R. 2015.” Shape classification of AltiKa 40-Hz waveforms using Linear Discriminant Analysis and Bayes Decision Rule in the Gujarat Coastal region “Marine Geodesy.
• Coastal and Hydrology Altimetry product (PISTACH) handbook, CLS-DOS-NT-10-246, SALP-MU-P-OP-16031-CN 01/00, 1. 0, Oct. 4, 2010
• Deng, X., and W. E. Featherstone. 2006. A coastal retracking system for satellite radar altimeter waveforms: Application to ERS-2 around Australia. J. Geophys. Res. 111: doi:10.1029/2005JC003039.
• Deng, X. 2003. “Improvement of geodetic parameter estimation in coastal regions from satellite radar altimetry.” PhD. Dissertation, Curtin University of Technology, Perth, Australia.
• Halimi, A., C. Mailhes, J. – Y. Tourneret, P. Thibaut, and F. Boy. 2013. Parameter estimation for peaky altimetric waveforms. IEEE Trans. Geosci. Rem. Sens., 51: 1568-1577.
• The PISTACH project for coastal altimetry: Status, products and early results, in Proc. OST-ST Meeting, Seattle, WA.
• Nelder, J.A. and Mead R. 1965. A simplex method for function minimization. Computer Journal, vol 7, no. 4, 308-313.
• Ray, R. D., 1999, A global ocean tide model from TOPEX/POSEIDON altimetry: GOT99.2, NASA Tech. Memorandum 1999-209478, Goddard Space Flight Center, Greenbelt, MD.
• SARAL/AltiKa Products Handbook, SALP-MU-M-OP-15984-CN, 2, 4, December 9, 2013
• Remya, G., Kumar, R., Basu, S., & Sarkar, A. (2011). Altimeter-derived ocean wave period using genetic algorithm. IEEE Geoscience and Remote Sensing Letters, 8(2), 354-358.
• R. Govindan, R. Kumar, S. Basu and A. Sarkar. " Altimeter-Derived Ocean Wave Period Using Genetic Algorithm, " IEEE Geosci. Remote Sens. Lett.,VOL 8.NO. 2,pp. 354 - 358, March 2011
• Sindhu, B., I. Suresh, A. S. Unnikrishnan, N. V. Bhatkar, S.Neetu and G. S. Michael 2007. Improved bathymetric data sets for the shallow water regions in the Indian Ocean. J. Earth Syst. Sci.,116,61–274.
• Sreejith, K.M., Rajesh, S., Majumdar, T.J., Srinivasa Rao G., Radhakrishna, M., Krishna, K.S., Rajawat A.S., 2013. High-resolution residual geoid and gravity anomaly data of the northern Indian Ocean - an input to geological understanding. J. Asian Earth Sci. 62, 616–626.

• User should refer User Handbook “Moving closer to the coast by SARAL/AltiKa: Geophysical Product for Indian Mainland Region” for complete reference to the algorithm and processing steps. For Handbook SARAL/AltiKa: Geophysical Product for Indian Mainland Region (Size: 1.14MB Format: PDF Tool: PDFView) Click Here
• For value added wave product:
• The wave power (P) is mathematically derived as
• 
• Where
• 1. P is Wave power per unit of wave-crest length (in Kilowatt/m)
• 2. R represents the satellite range
• 3. H m0 is the significant wave height (in meters)
• 4. T is wave period (in seconds)
• 5. ρ is the density of water (in kilogram/cubic meter)
• 6. g is the acceleration due to gravity (in meters/square seconds)

• Wind power is generated by using;
• We have assumed unit area in this equation. is density of air and is wind speed.

• Based on the availability of the Altimeter dataset over the study region (Data Gap, altimeter track loss, bad weather, etc.). Geophysical and atmospheric range corrections have been obtained from the standard 1-Hz product of SARAL/AltiKa.

• Data problems due to bad weather (heavy rain).
• Onboard tracker failure leads to unusable data.
• Coastal contamination may lead to erroneous estimate of the derived parameters.

• Netcdf file:
• SRL_CCC_TTTT_yyyymmddHHMMSS_yyyymmddHHMMSS_INDIANCOAST_SIGDR_VER1.1.nc;
• JPG Files:
• ssha_cycCCC_yyyymmdd_yymmdd.jpg (sea surface height anomaly image)
• swh_cycCCC_yyyymmdd_yymmdd.jpg (swh image)
• wind_speed_cycCCC_yyyymmdd_yymmdd.jpg (wind speed image)
• Where
• CCC is the cycle number and TTTT is the track number.,
• first yyyymmddHHMMSS is the start time of the file., and
• second yyyymmddHHMMSS is the end time of the file..

• For values added wind wave power product:
• wind_power_cycCCC_yyyymmdd_yymmdd.jpg (wind power image)
• wave_power_cycCCC_yyyymmdd_yymmdd.jpg (wave power image)

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