Contribution of Tides to Sea Level Variations Along Visakhapatnam, India

Abstract

The sea level variations along Visakhapatnam coast are governed by astronomical tides and nontidal oscillations including atmospheric pressure, winds, coastal currents, Ekman Pumping, and river influx. Tidal and nontidal sea level oscillations are usually studied separately because of the vastly different ways in which they are forced. In this study the tidal oscillations along Visakhapatnam are analyzed using GOTIC2 tidal model. The correlation between monthly mean sea level and monthly mean tides is 47% (r = 0.68) and increases to 54% (r = 0.74) when applied for inverse-barometric effect. The major six partial tides are computed and presented. The tidal variations from Neap tide to Spring tide are studied.

Keywords:

• Sea level
• tides
• Visakhapatnam
• tidal constituents

Acknowledgements

P. Sreenivas sincerely acknowledges the Council of Scientific and Industrial Research (CSIR), New Delhi, India, for providing research fellowship. We thank Dr. K. Matsumoto et al. for providing the GOTIC2 model. The use of sea level and GIA data from PSMSL and the NCEP sea surface pressure data from AVISO have been gratefully acknowledged.