Annual average rainfall levels vary greatly across Bangladesh. The average annual rainfall in Bangladesh is generally high; areas over most of the country receive more than 2,000 mm, but the variation in the rainfall levels ranges from 1,500 mm to more than 5000 mm. The monthly rainfall variability (figure 3.9) indicates the need, in the context of the present study, to examine the exposure of the rural rice economy to weather-driven stresses such as drought or excess rainfall.
Figure 3.9. Bangladesh: Monthly (A) Average and (B) Cumulative Precipitation in Bangladesh.
Note: Each error bar in graph A represent one standard deviation.
Source: Authors
Bangladesh is characterized by a uniform tropical to subtropical warm and wet climate. Temperatures have small mean monthly variation and exhibit three distinct annual periods (figure 3.10). The hot March–April premonsoonal period contains the annual highest temperatures, which peak over 40°C during five or more days and with mean national temperatures of over 34°C. With over 75 percent of the annual cumulative rainfall, the May–October monsoon season is characterized by a drop in temperature (ranging from 20 to 36°C) in June due the precipitations and a mean national temperature of 31°C. The dry November–February winter period shows cooler temperatures that drop to an average lowest at the end of December and can reach the lowest of 5°C in the north.36
