the rate of local relative sea level rise is 7.0 mm a year around the coastal areas of the country. An alarming trend indeed for the future, but this is only one side of the coin. The other side is that the average sediment accumulation rate for the last few hundred years in the coastal areas of Bangladesh is 5.0-6.0 mm a year. What we see is that the sea level rises 7.0 mm/year and the land rises 5.0-6.0 mm/year; it means the relative sea level rise in the coastal areas of Bangladesh is 1.0-2.0 mm/year. The elevation of the Barisal town, which stands only at a distance of about 90 kilometers from the coastline, is three meters above Mean Sea Level. So to reach up to Barisal town level, the sea will take 1,000 (one thousand) years, if its level rises at three mm/year. This is one aspect of the picture; and the other aspect is that the coastline of Bangladesh is not static, rather progressing outward due to the fact that a tremendous amount of silt is being deposited on the shore in the Meghna estuary, causing land accretion.
Each year about 2.4 billion tons of sediment from the Himalayas is carried by the rivers of Bangladesh to the Bay of Bengal, and deposited on the continental shelf, causing accretion of land along the coast of the country. The high sediment load results in a net accretion of about 35 square kilometers of land per year to Bangladesh.
Satellite pictures show new land, measuring no less than 20,000 (twenty thousand) square kilometers, being formed in the Bay of Bengal in the coastal zones of Bangladesh.
Inhabitants on our coastal islands, Neejhum Deep, Char Kukrimukri, Char Jabbar etc., know how every year new shoals in our coastal zones are coming up, and how the water is getting more and more shallow between these shoals. We know Bangladesh has been formed over tens of thousands of years through the settling down of sediment on the bed of the Bay. Only about three thousand years back, one of our seaports was near Gopalganj in Faridpur district. We can see how far the coastline of our country has extended during the last three millennia.
. A debt you are destined to pay forever. Joy dalal!
