1. Tropical cyclones are important rainmakers, providing 25 percent or more of available rainfall to places like Japan, India, and Southeast Asia—not to mention Texas, which desperately needs a dousing ASAP.
2. Tropical cyclones help maintain the global heat balance by moving warm tropical air away from the equator and towards the poles. Without them, the tropics would get a lot 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.
3. Paradoxically, fragile barrier islands need hurricanes for their survival—especially now, when sea levels are rising. Although hurricanes erode beaches on the ocean side of barrier islands, they build up the back sides of the same islands by depositing new sediments via winds and waves. This dynamical process keeps barrier islands alive.
4. Tropical cyclones stir up the ocean and drive the process of upwelling, thus playing a part in the thermohaline circulation—another important transport mechanism distributing heat between the equator and the poles and keeping the earth's temperature in better balance.
5. By stirring the ocean, tropical cyclones also cycle nutrients from the seafloor to the surface, boosting ocean productivity and setting the stage for blooms of marine life.