Study on the trends of rainfall and temperature patterns to identify the influence of climate variation in coastal cities in Sri Lanka

Abstract

Climate change has been universally recognized as a fundamental human development challenge in 21stcentury and thereafter; which impacts both natural and built environment. Although different parts of the world are predicted to be affected by climate change to varying degrees, many of the studies focused on climate change in global or region level. However, there is a dearth of climatological studies addressing the temporal trends in rainfall and temperature at city scale. On other hand recent rainfall and temperature extremes have adverse impacts on the natural and built environment of most of coastal cities in Sri Lanka.In this context this research attempted to examinetrends of rainfall and temperature patterns over the last four decades in seven coastal cities (namely; Rathmalana, Hambantota, Trincomalle, Puttalam, Katunayake, Batticaloa and Galle) in Sri Lanka to see whether they support toclaim the long-term climate changeby identifying temporal trends in the rainfall and temperature during the period of 1971-2011.The findings of the study revealed averaged over all stations;the indices of temperature extremes indicate warming of both daily minimum and maximum temperature between 1971 and 2011. For precipitation, most of the indices show significant changes. Relative to the changes in the total amounts, there is a very significantchangein the precipitation extreme days. Accordingly this study emphasize the need of integrating the climatic variations wisely in the urban planning can invest the capital of the country to the development rather than unnecessarily spend it on post disaster rehabilitations.