Rainfall – Without a doubt, this is the most important benefit of a cyclone. Although tropical cyclones can take an enormous toll on lives and personal property, they can be important factors in the precipitation regimes of the places they affect and bring much needed rain to otherwise dry or drought related regions.
Widespread heavy rainfall from a cyclone has several benefits as it is usually spread over a number of days. Increased rainfall helps the ground to hold more moisture, which in turn means that future crops have a major benefit with more moisture being made available for a longer time. This in turn boosts agricultural production. Important rainmakers, tropical cyclones provide over 25% of rainfall in India and Southeast Asia. Japan receives over half of its rains from typhoons. Rain can also help clear some pollutants from air.
Heat Balance - Tropical cyclones help maintain the global heat balance by moving warm tropical air away from the equator, towards the poles. Without them, the tropics would get hotter and the poles a lot colder. A typical tropical cyclone releases heat energy of about 50 to 200 exajoules a day. That's equivalent to 70 times our worldwide energy consumption.
Cyclone rain cools the weather in its vicinity for some time, dropping the temperatures by significant levels (2 to 6 degree Celsius)
Sea life - Increased rainfall from cyclones help river systems by flushing out silt, carving out new channels and opening up areas to inundation of the wet lands there by increasing both nesting and food supplies. These major flushes open up areas that fish breed in, thus increasing the number of fish in the sea as well as creating increased food supplies for native species.
By stirring the ocean, tropical cyclones also cycle nutrients from the seafloor to the surface, boosting ocean productivity and setting the stage for blooming of marine life.
Islands - Fragile barrier islands need hurricanes for their survival. Although hurricanes erode beaches on the ocean side of barrier islands, they build up the inner areas of the same islands by depositing new sediments via winds and waves. This dynamical process keeps barrier islands alive. No hurricanes and no cyclones will mean these small islands will disappear every year, especially now when the sea levels are rising rapidly.
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