 The names of significant tropical cyclones in the North Atlantic Ocean, Pacific Ocean, and Australian region are retired from the naming lists and replaced with another name.Tropical cyclones that cause extreme destruction are rare, although when they occur, they can cause great amounts of damage or thousands of fatalities.The 1970 Bhola cyclone is considered to be the deadliest tropical cyclone on record, which killed around 300,000 people, after striking the densely populated Ganges Delta region of Bangladesh on November 13, 1970.