Climate Change Projections and Their Consequences on Agro-Climate in Sugarcane Growing Areas of Sevanagala, Sri Lanka

Abstract

An analysis was conducted to estimate the agro-climatic changes, which would incur due to projected climate change scenarios on sugarcane cultivation in Sevanagala, Sri Lanka over the next 70 years. The general circulation model developed by the Beijing Meteorological Centre was used with Representative Concentration Pathways scenario 6.0 to simulate the climate variables of maximum and minimum temperatures, and rainfall for years 2030, 2050, and 2090. The goodness of fit test was conducted against simulated and observed data using 10-year dataset from 2010 to 2019. The future climate was compared using a baseline data set, which was generated by averaging 10 years of data from 2010 to 2019. The results indicated that by 2090, the average annual minimum and maximum temperatures would increase by 1.2 °C and 1.4 °C, respectively. However, annual maximum and minimum temperatures may remain within the favourable range for sugarcane cultivation. The annual rainfall is expected to increase by 6.0% in 2090 relative to baseline values. The results demonstrated the stability of the effective rainfall. The evapotranspiration would increase by 3.7% by the year 2090 relative to baseline values. The soil moisture deficits for sugarcane planted in the Yala and Maha planting seasons are also expected to increase by 6.7% and 12.6%, respectively in 2090. As a result of increased evapotranspiration, additional irrigation might be needed to maintain the productivity of sugarcane cultivation indicating the climate-related risks for future rain-fed sugarcane cultivations in Sevanagala, Sri Lanka.