Explained: Is climate change fuelling hurricanes?

After a relatively calm beginning to the season, Hurricane Fiona pounded the Dominican Republic and Puerto Rico, leaving more than 1 million people without power or running water.

Thousands of homes and businesses lost power after the storm struck Canada's east coast on Saturday.

Although scientists have not yet concluded that Fiona's behaviour or severity was influenced by climate change, there is compelling evidence that these catastrophic storms are getting worse.

Does climate change affect hurricanes?

Yes, hurricanes are becoming wetter, windier, and generally more powerful as a result of climate change. Additionally, there is proof that it is making storms move more slowly, allowing them to dump more water in one location.

Climate change would have caused the earth to become much hotter if it weren't for the oceans. However, over the past 40 years, the ocean has absorbed 90% of the warming brought on by emissions of heat-trapping greenhouse gases. Near the water's surface, the majority of this ocean heat is concentrated. Stronger winds and increased storm severity may result from this added heat.

Additionally, a storm's ability to produce more rainfall can increase due to climate change. A warmer environment can store more moisture, thus water vapour accumulates until clouds form and raindrops are released, sending down heavy rain.

'Season' for hurricanes is changing

The normal "season" for hurricanes is changing as a result of climate change since more months of the year are becoming storm-friendly. Additionally, hurricanes are making landfall in places that deviate greatly from the historical norm.

With over 120 direct impacts since 1851, Florida has experienced the most hurricane landfalls in the United States. However, certain storms are becoming more intense and making landfall further north than they did in the past; this poleward shift, according to scientists, may be caused by the increase in global air and ocean temperatures.

According to Florida State University atmospheric scientist Allison Wing, this tendency is concerning for mid-latitude cities like New York, Boston, Beijing, and Tokyo because their "infrastructure is not prepared" for such storms.

However, it's uncertain whether climate change is having an impact on the frequency of storms. According to a study published in December in Nature Communications, one group of experts recently claimed to detect a rise in the frequency of North Atlantic storms during the previous 150 years. Yet the further study is being done.

How do hurricanes form?

Warm ocean water and humid, moist air are the two key components needed for hurricanes. Warm seawater evaporates, releasing heat energy into the atmosphere. The storm's winds become stronger as a result. Without it, hurricanes can't become stronger and will eventually die.

Cyclone, typhoon, hurricane - what's the difference?

These large storms have varied names based on where and how they formed, although theoretically being the same phenomenon.

When storms that develop over the Atlantic Ocean or the central and eastern North Pacific attain wind speeds of at least 74 miles per hour, they are referred to be "hurricanes" (119 kilometres per hour). They are referred to be "tropical storms" up until that moment.

Typhoons in East Asia are the name given to ferocious, spinning storms that develop over the Northwest Pacific, while "cyclones" develop across the Indian Ocean and South Pacific.

(with inputs from agencies)