CR 76:241-252 (2018)  -  DOI: https://doi.org/10.3354/cr01535

ABSTRACT: Recent studies have identified Bangladesh as one of the most vulnerable countries in the world with respect to climate change. The objective of this study was to determine the long-term trends in annual, seasonal, and monthly air temperature, relative humidity, heat index, and rainfall in the south-western region of Bangladesh. The non-parametric Mann-Kendall trend test and Sen’s slope methods were applied to quality-controlled time series data at 7 meteorological stations distributed across the region to detect the significance and magnitude of the trends in the selected climatic variables during 1960-2010. Based on these analyses, (1) significant rising trends in daily maximum, minimum, and mean temperatures were detected at a majority of the stations within the area, with pronounced warming during summer months; (2) relative humidity showed a significant increasing trend at both annual and seasonal scales over the region; (3) analysis of the heat index, which indicates what the temperature feels like to the human body when relative humidity is factored in with temperature, displayed a distinct increase in level of discomfort, exposing the population of Bangladesh to heat-related health hazards; and (4) the distribution of monthly rainfall patterns in the region seems to be changing, with significant variation in rainfall trends within the monsoon season by 6-7 mm yr^-1. The findings of this study increase our understanding of regional climate patterns, which can simplify larger analyses such as water budgets and agricultural production that depend on these types of data inputs, especially for the south-western region of Bangladesh.

KEY WORDS: Climate change · Bangladesh · Trends · Significant · Magnitude