Sylhet - Geography and Climate

Geography and Climate

Sylhet is located at 24°53′30″N 91°53′00″E / 24.8917°N 91.8833°E / 24.8917; 91.8833, in the north eastern region of Bangladesh within the Sylhet Division, within the Sylhet District and Sylhet Sadar Upazila. The climate of Sylhet is humid subtropical with a predominantly hot and humid summer and a relatively cool winter. The city is within the monsoon climatic zone, with annual average highest temperatures of 23 °C (Aug-Oct) and average lowest temperature of 7 °C (Jan). Nearly 80% of the annual average rainfall of 3,334 mm occurs between May and September.

The city is located within the region where there are hills and basins which constitute one of the most distinctive regions in Bangladesh. The physiography of Sylhet consists mainly of hill soils, encompassing a few large depressions known locally as "beels" which can be mainly classified as oxbow lakes, caused by tectonic subsidence primarily during the earthquake of 1762. It is flanked by the Indian states of the Meghalaya in the north, Assam in the east, Tripura in the south and the Bangladesh districts of Netrokona, Kishoregonj and Brahmanbaria in the west. The area covered by Sylhet Division is 12,569 km², which is about 8% of the total land area of Bangladesh.

Geologically, the region is complex having diverse sacrificial geomorphology; high topography of Plio-Miocene age such as Khasi and Jaintia hills and small hillocks along the border. At the centre there is a vast low laying flood plain of recent origin with saucer shaped depressions, locally called Haors. Available limestone deposits in different parts of the region suggest that the whole area was under the ocean in the Oligo-Miocene. In the last 150 years three major earthquakes hit the city, at a magnitude of at least 7.5 on the Richter Scale, the last one took place in 1918, although many people are unaware that Sylhet lies on the earthquake prone zone of Bangladesh.