Sea level rising up to 20mm a yr

The annual rise of sea level in Bangladesh ranges between 6mm and 20mm, posing threats to the country's agriculture, land and population, according to a Department of Environment study. 

The study, conducted between April 2013 and Oct 2015, analysed tidal water data of the last 30 years in the entire coastal zones of the country. It focused on the trend analysis of tidal water level to visualise the historical change of sea level rise in the coasts of Bangladesh.  

According to the study carried for the first time in Bangladesh with its own capacity, the sea level rises 7 to 8mm a year in the western coastal region including Satkhira, Khulna and Barisal.

The rise is 6 to 9mm annually in the central coastal region, which covers Noakhali, Laxmipur and their adjacent districts while 11 to 20mm rise has been observed in the coastal areas of Chittagong and Cox's Bazaar.

“The sea level rise will have serious impact on the country in future. Salinity will be increased, agriculture will be badly affected, and there will be a shortage of drinking water,” said Dr Ainun Nishat, a climate change expert, who finalised the study.

He said that previously secondary data were used to refer to sea level rise.

“Now we can monitor and assess the impact using our own data,” he told The Daily Star last night. 

The trend analyses have been carried out using the water level data of Bangladesh Inland Water Transport Authority (BIWTA), Bangladesh Water Development Board (BWDB) and Chittagong Port Authority. 

The study recommends installing at least 10 high precision automatic tidal gauge stations along the coastline of Bangladesh. It says regular monitoring of the tidal water data is required to assess the sea level rise.

Climate Change Cell of the DoE conducted the study with technical assistance from Center for Environmental and Geographic Information Services (CEGIS), Institute of Water Modeling (IWM) and Institute of Water and Flood Management of Buet.

The study paper will be disclosed today at a workshop at the city's CIRDAP International Conference Centre where Malik Fida Abdullah Khan, director, climate change of CEGIS, will present the keynote paper on the study findings while Pauline Tamesis, UNDP country director, and Dr Qazi Kholiquzzaman Ahmad, chairman, Palli Karma-Sahayak Foundation, among others, will deliver speeches.

Dr Ainun Nishat, Professor Emeritus of BRAC University, will moderate the workshop.