Md. Khairul Hasan - Sub-divisional Engineer, Bangladesh Water Development Board, Dhaka, Bangladesh
Farhana Parvin - Officer- Research and Knowledge Management, Disaster Management Watch
Nishat Tasnim - Department of Disaster Science and Management, University of Dhaka, Dhaka-۱۰۰۰, Bangladesh

In Dhaka city, the ambient temperature is changing as a consequence of changing climate and urbanization. The alteration in temperature is one of the most significant influencing factors that affect Reference Evapotranspiration (ETo). The study is comprehensively designed to examine the pattern of change in ETo over the period from ۱۹۵۳ to ۲۰۱۸. To fulfill the purpose of the study, temperature data of Dhaka throughout this period have been used. The trend of ETo has been analyzed for four different seasons: Pre-monsoon (March-May), Monsoon (June September), Post-monsoon (October- November), and winter (December- February). To evaluate the statistical significance of these patterns, a Mann-Kendall rank statistical significance test has been used. The result shows different trends for different seasons. There has been downward trending during the pre-monsoon and winter seasons, where the upward trending has been found during Monsoon and Post monsoon periods. All these trends are statistically significant at the ۹۵% significance level.In Dhaka city, the ambient temperature is changing as a consequence of changing climate and urbanization. The alteration in temperature is one of the most significant influencing factors that affect Reference Evapotranspiration (ETo). The study is comprehensively designed to examine the pattern of change in ETo over the period from ۱۹۵۳ to ۲۰۱۸. To fulfill the purpose of the study, temperature data of Dhaka throughout this period have been used. The trend of ETo has been analyzed for four different seasons: Pre-monsoon (March-May), Monsoon (June September), Post-monsoon (October- November), and winter (December- February). To evaluate the statistical significance of these patterns, a Mann-Kendall rank statistical significance test has been used. The result shows different trends for different seasons. There has been downward trending during the pre-monsoon and winter seasons, where the upward trending has been found during Monsoon and Post monsoon periods. All these trends are statistically significant at the ۹۵% significance level.

Temperature change, Seasonal variation, Reference Evapotranspiration, Climatic variability, Mann Kendall Trend Test