Acta Scientific Microbiology (ISSN: 2581-3226)

Research Article Volume 4 Issue 7

Comparison and Validation of Coastal Sea Level Measurements in the Indian Ocean Regions Using Coastal Altimetry

Acharyulu PSN1*, Vignudelli Stefano2 and Prasad KVSR1

1Department of Meteorology and Oceanography, Andhra University, Visakhapatnam, Andhra Pradesh, India
2Consiglio Nazionale delle Ricerche, Istituto di Biofisica, Pisa, Italy

*Corresponding Author: Acharyulu PSN, Department of Meteorology and Oceanography, Andhra University, Visakhapatnam, Andhra Pradesh, India.

Received: May 27, 2021; Published: June 24, 2021


Satellite altimetry provides an important measurement source for coastal studies. The main aim of this study was to make an effort to check the availability of valid altimeter data and to compare and validate altimeter data in the coastal region of India. The study shows that by adopting specific coastal processing, it is possible to retrieve valid altimeter measurements in the coastal regions. The combined use of improved coastal multi-altimeter data would allow us to efficiently observe the temporal and spatial scales of coastal dynamics [16]. Thus, in the present study, two different altimetry missions were considered. The coastal sea-level data was computed from two different altimeter missions the Jason-2 PISTACH coastal data and SARAL Altika data separately and for sea level validation only the RED3 re-tracker and for SARAL 40 Hz high-frequency data was analysed and validated with In-situ tide gauge and PSMSL data. The RED3 re-tracker from Jason-2 PISTACH coastal product with In-situ measurements show that the valid altimeter data can be retrieved around 10 km close to the coast also. Also, the 41 point filtered data was able to reduce the noise in the data set and be able to capture all the oceanographic signals in the raw RED3 re-tracker. The comparison of RED3 re-tracker and filtered data show good matching with the In-situ data. This data helps us to obtain valid altimetry measurements more close to the coast. Similarly, for the SARAL Altika, SSHA measurements show very promising results in the coastal regions of India. This SARAL also enables us to reach as close as 3 km close to the coast because it is the first of its kind to provide sea level measurements in the proximity of the coastal regions due to its narrow footprint size. The validation of altimeter data from multiple missions with tide gauge data shows encouraging results. Along-track comparison shows that valid altimeter measurements were available close to the coast. Improvement of both qualitative and quantitative measurements in the coastal zone was observed from the coastal altimetry.

Keywords: Satellite Altimetry; Coastal Zone; Coastal Processes; Sea Level; Seasons; Tide Gauge


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Citation: Acharyulu PSN., et al. “Comparison and Validation of Coastal Sea Level Measurements in the Indian Ocean Regions Using Coastal Altimetry”. Acta Scientific Microbiology 4.7 (2021): 123-136.


Copyright: © 2021 Acharyulu PSN., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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