"Imagine there is a wall in front of your house. Because of it, flood water and gusts of wind cannot get into your home. The Sundarbans does exactly the job of that wall for Bangladesh's south-west coast."

Environmentalist Dr AQM Mahbub made the comment while explaining how the Sundarbans served as a shield protecting coastal areas from Cyclone Bulbul. He fears that without the forest the coast could have suffered major devastation.

Cyclone Bulbul struck Satkhira, next to the Sundarbans, on Saturday night and then swept over the Khulna and Bagerhat parts of the forest. But because the storm was blocked by the forest's trees, the powerful cyclone could not have its full impact.

At landfall its wind speed was up to 140 km an hour, but because of the Sundarbans' trees its effect was felt at around 100 km an hour, Dr Mahbub says.

During a natural disaster a forest takes two kinds of blow: first the high-speed wind, then the tidal surge. Blocked by the Sundarbans, the cyclone's winds reached the settlements of Khulna and Bagerhat at comparatively lower speed.

Experts say that where the cyclone's speed in the forest was 100 km an hour, it lost strength on its way through the forest and turned into gusty wind by the time it reached populated areas.

The storm surge, meanwhile, was obstructed by the Sundarbans before reaching settlements, so the height of the waves fell considerably.

Source: BBC Bangla. First published in Bengali on The Agro News.