Why do we have hurricanes? Do they do any good?

It is easy to see weather events like hurricanes as “bad weather” when they wash away our homes or claim human lives.

But hurricanes are important to global ecology in surprising ways.

Hurricanes are nature’s way to mix warmer surface water with cooler, nutrient-rich water from deeper in the ocean, a process called upwelling. This process can help drive food production in the ocean. 

One study said that the loss of foliage in hurricanes and other natural disasters aids long-distance seed dispersal.

This mixing breaks up patches of bacteria that lurk in the water and can bring an earlier end to the red tide, which can occur along the Gulf Coast and the West Coast.

Ecological benefits

Hurricanes can help tropical and subtropical environments by:

Flushing out lagoons and wetlands, removing weeds and waste 

Moving sediment from bays into marsh areas, which revitalizes nutrients 

Alleviating thermal stress on coral reefs by upwelling cooler waters 

Exposing the limestone structure of coral reefs, which provides a foundation for corals to grow on 

Global heat balance
Hurricanes help create a balance of energy on Earth by transferring heat from the tropics to higher latitudes in the ocean and atmosphere. This process helps slow down the warming of the Earth’s atmosphere. 

Replenishing barrier islands and inland plant life
Hurricanes can help replenish barrier islands and inland plant life. 

Relieve droughts
Tropical cyclones are extremely efficient at rainfall production, and thus, can also be efficient drought busters.

In areas of drought, such as parts of the Southeast and Northeast, rain from a tropical cyclone can be beneficial.

Moisture from decaying tropical cyclones in the eastern Pacific occasionally gets caught up in the west-to-east flow of the United States and reaches the Desert Southwest. California and much of the Desert Southwest are desperate for rain, so an influx of moisture from a tropical system could be good news for that region.

Of course, often tropical cyclone rain is “too much of a good thing” for any drought area.

Tropical Storm Debby in 2012 erased a drought in the Deep South, but also triggered major inland flooding in those same drought areas of north Florida and south Georgia.