Cyclone Mora Hits Vulnerable Bangladesh
Cyclone Mora, a Category 1 storm with peak winds of 75 mph, smacked into the low-lying nation of Bangladesh on May 31. Besides the strong winds, Mora brought heavy rains and several feet of storm surge, leading to concerns for the densely packed coastal communities.
NOAA/NASA Suomi/NPP satellite image taken on May 29, 2017 of Cyclone Mora in the Bay of Bengal. Mora would make landfall in Bangladesh soon thereafter bringing strong winds, heavy rains and storm surge. NOAA Climate.gov image with data from the NOAA Environmental Visualization Laboratory.
Luckily, Cyclone Mora was not a particularly strong cyclone. Even so, and more importantly, Bangladesh worked to evacuate hundreds of thousands of people before landfall—a task made difficult by Mora’s quick transition from depression to cyclone from May 28 to 29, leaving less time for evacuation. Sadly, the storm still killed at least seven people, with others still missing.
Impacted areas in India, Bangladesh and Myanmar observed around three to six inches of rain with the highest amounts located inland across higher elevations. Media quoting local officials reported that over 50,000 homes were destroyed or damaged in some of the worst hit areas. This includes damages to shelters located in camps housing hundreds of thousands of Muslim Rohingya refugees from neighboring Myanmar.
While Mora certainly could have been worse, it will still leave a lasting impression for months ahead.
Bangladesh’s cyclone history
Some of the world’s worst weather disasters have happened to communities across the Bay of Bengal, that triangular shaped Bay on the eastern side of India, which also borders Bangladesh and Myanmar. Due to the bay’s unique funnel shape, its many inlets, and the flat, low-lying land areas that border it, storm surge can not only be magnified, but it can also move far inland, impacting densely populated regions near the coast.
NASA TERRA/MODIS satellite image taken on May 1, 2008 of Cyclone Nargis in the Bay of Bengal. Cyclone Nargis made landfall in Myanmar on May 2 killing an estimated 138,000 people. NOAA Climate.gov image with data provided from NASA.
These geographic traits are one of the reasons that the list of deadliest tropical cyclones in world history is littered with storms in the Bay of Bengal. According to one list on Weather Underground, eight of the top ten deadliest cyclones on record have occurred in the Bay of Bengal. The deadliest on record is generally said to be the Great Bhola Cyclone in 1970 which killed 300,000 to 500,000 people in India and modern-day Bangladesh (at the time East Pakistan). In 1991, a cyclone with 155mph winds and a 20-foot storm surge killed nearly 140,000 people in Bangladesh. And if you are thinking these sorts of things cannot happen today, in 2008, Cyclone Nargis came ashore along the Irrawadday River Delta in Myanmar as a Category 4 storm with over 10 feet of storm surge. Nargis and the waters of the Bay of Bengal came rushing through communities across the Delta, killing an estimated 138,000 people.
Physical geography isn’t the only reason Bangladesh faces significant risk from cyclones. Of the world’s 100 most populous countries, Bangladesh is the most densely populated. It is also among the poorest (GDP of $3,900 compared to the United States’ $57,300). These socioeconomic factors make the country especially vulnerable.
Compare elevation (m) and population density (persons/square km) images for countries around the Bay of Bengal. Elevation data is from the United States Geological Survey (USGS). Population density data is from NASA’s Socioeconomic Data and Applications Center (SEDAC).