There are traditionally six seasons in the Bengali year: Summer, Rain, Autumn, Late Autumn, Winter and Spring. All the seasons of Bangladesh bear the different characteristics from one to another place. Bangladesh has been divided into seven climatic sub-regions like the Seven Soil Tracts of Bangladesh. Thes seven climatic sub-regions are South-Eastern, North-Eastern, Northern part of the north region, North- western region, Western dry region, South-western region and South-central region.
Table of Contents
The details about 7 climatic sub-regions of Bangladesh as the following-
1. South Eastern
This comprises the Chittagong region and a strip of country north to Comilla. The hills over a thousand feet in height have the type (b) climate. The rest of the area has the small change of temperature rarely going over a mean of 320 C and below a mean of 120C. Rainfall is heavy usually over 254cm. In winter dew-fall is heavy.
This includes most of the east and south Sylhet and a strip south of the Meghalaya plateau. Here mean maximum temperature is rarely above 320 C but mean minimum temperature is 100C and below. Average humidity is even more than (a). In this sub-region only is winter rain appreciable. Fog is very common in winter. This is the cloudiest part of Bangladesh. The higher hills and mountains of Chittagong region can be classified in this sub-region.
3. Northern part of north region
4. This is an area of extremes. In summer maximum temperature is well above 320C. Where, as in winter the mean minimum is below 100C. The summer is dry, with a scorching westerly wind, but the rainy season is very wet with 200 to 300cm rainfall.
5. North- western region
Except that the extremes are less and the rainfall is lower in this sub-region is similar to (c). The lower rainfall makes this area both atmospherically and pedologically drier.
6. Western dry region
This sub-region comprises Rajshahi district and parts of the adjacent district. This is the driest area of Bangladesh with rainfall generally below 150cm and summer humidity is less than 50 %. In summer, it is the hottest and driest of all sub-regions. Means summer maxima are over 320C.
7. South-western region
Here the extremes of the sub-regions to the north are somewhat tempered. Rainfall is between in 152 to 175cm. Mean summer maxima are below 320C. Rainfall is heavier than in sub-region (e).
8. South central region
Rainfall is abundant, being above 190cm. The range of temperature is as can be expected much less than to the west but somewhat more than in sub-region (a). This is a transitory zone between (d) and (f).
Crop Production of these sub-regions may increase or decrease by The Effects of Weather and climate.