Evaluation of the wave height used in the design of offshore structures considering the effects of climate change

• Published in: Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
• Main Authors: RADHIKA, S, DEO, MC, LATHA, G
• Format: Article in Journal/Newspaper
• Language: English
• Published: SAGE PUBLICATIONS LTD 2013
• Subjects: Design Waves; Climate Change; Wave Statistics; Offshore Design; Neural Network; North-Atlantic Ocean; Tropical Cyclones; Continental-Shelf; Projections; Wind; Intensity; Scenario; Coast; Sea; Indian; North Atlantic
• Online Access: http://dspace.library.iitb.ac.in/jspui/handle/100/14910; https://doi.org/10.1177/1475090212443177

Evaluating the wave height used in the design of offshore structures simply on the basis of observed or hindcast wave heights may be an inadequate approach in light of the potential changes in the climate due to global warming. In this study an attempt is made to estimate the significant wave height with a return period of 100 years at three different locations along the Indian coastline considering the effects of climate change. The future values of wave height are generated by regionalizing or downscaling wind information obtained from a general circulation model run for various scenarios of global warming. The predicted wave heights for the next 30 years are then fitted to Gumbel or Weibull distributions to estimate the significant wave height with a return period of 100 years and these estimates are compared with those obtained from the past 30 years hindcast. In general, it is found that if climate change is considered in the evaluation of design-significant wave heights then a considerable increase in their magnitudes is likely. On the basis that the Weibull distribution provides a statistically more reliable fit to the data then the recommended increase in the 100-year significant wave height is in the range 8-42% for the considered location in the Bay of Bengal and 27-44% and 22-32% for the two considered locations in the Arabian Sea.