Many small island states live in fear of natural disasters, as unprecedented storms become more frequent, says Commonwealth Secretary-General Patricia Scotland, RNZ reports.

Natural disasters had increased by 75 percent over the past two decades, causing $US3 trillion of economic losses, Scotland told RNZ Pacific. The worst affected were developing countries, she said.

"If you look at where those losses occurred, the majority - 99 percent of them - occurred in the Global South, and yet we know that the G20 are responsible for 80 percent of the global greenhouse gases," Scotland said.

"The least developed nations contributed to just 5 percent of greenhouse gas emissions."

Earlier this year, Vanuatu was hit by two cyclones, Judy and Kelvin, in the space of four days. This came just under three years after the country was hit by category 5 Cyclone Harold in 2020 and eight years after the Category 5 Cyclone Pam in 2015 - both the largest recorded cyclones to hit Vanuatu.

Fiji recorded its most powerful cyclone in 2016 with Cyclone Winston, while Tonga recorded its most powerful cyclone in 2018 with Cyclone Gita. Both countries have recorded three severe cyclones in ten years.

In February, Mauritius, in the Indian Ocean, was hit by Cyclone Freddy - a five week long storm - the longest lasting tropical cyclone ever recorded.

The frequency of storms has also increased in the Caribbean region. In 2019, Category 5 Hurricane Dorian was the most powerful storm to have struck the Bahamas, leaving over 70,000 people homeless and 84 dead.

"My own country of birth, the Bahamas, was devastated," Scotland said, adding that "200 percent of our GDP was destroyed."

"This threat, particularly to the small and developing countries, is existential.

"It's omnipresent and now that we're entering the hurricane season, for instance in the Caribbean, we're all wondering who is next?

"Who will be the country that will be struck, and everyone knows it's going to be someone and they're all praying it's not them."