As Hurricane Melissa made its way from the Atlantic Ocean into the Caribbean and towards Jamaica this week, it passed through waters the temperature of a lukewarm bath.<\/p>\n
Just south of the island country, it hit waters above 30 degrees Celsius, where it rapidly intensified into a category five storm.<\/p>\n
Hurricanes, or tropical cyclones, use warm water to gain their power; the hotter the water, the more powerful they become.<\/p>\n
According to Climate Central, Hurricane Melissa travelled over waters made 1.4C warmer on average by human-caused climate change.<\/p>\n
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The water in the Caribbean Sea reached over 30C on Monday. (ABC\/NOAA)<\/p>\n
Climate Central scientist Kristina Dahl said Hurricane Melissa was “absolutely historic”.<\/p>\n
“It’s going to go down as one of the strongest storms on record in the Atlantic,” she said.<\/p>\n
“It’s also very clear that this storm bears the fingerprints of climate change.<\/p>\n
“We know that the waters that it passed over as it was churning through the Caribbean were made about 1.5C warmer because of climate change, and all that extra heat made the storm stronger.”<\/p>\n
When Hurricane Melissa hit those exceptionally warm waters, it moved incredibly slowly, giving it time to gain strength and power.<\/p>\n
It then underwent what is known as extreme rapid intensification \u2014 with an increase of 111 kilometres per hour in just 24 hours, which is double the standard threshold for rapid intensification.<\/p>\n
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To rapidly intensify, a storm needs to cross extraordinarily warm waters that extend into deeper layers, providing a reserve of fuel and energy. (ABC News: Sharon Gordon)<\/p>\n
“We see more and more hurricanes undergoing rapid intensification as the climate warms,” Dr Dahl said.<\/p>\n
“And most of the storms in the Atlantic basin this year that have reached hurricane strength underwent rapid intensification.”<\/p>\n
‘Storm of the century’<\/p>\n
Hurricane Melissa, which has been dubbed the “storm of the century” by the World Meteorological Organization, at least so far, also shook off three different meteorological conditions that usually weaken major hurricanes.<\/p>\n
Normally, when a storm like this gets strong enough, the eye wall collapses and is replaced by a smaller eye, at least temporarily weakening the system.<\/p>\n
Hurricane Melissa showed some signs of being ready to do this, but it never did, according to University of Miami hurricane researcher Brian McNoldy.<\/p>\n
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A high-resolution view of the eye of Hurricane Melissa in the centre of dense cirrus clouds. (NOAA)<\/p>\n
The second thing that usually weakens hurricanes is mountains, even small island ones.<\/p>\n
“It was next to a big mountainous island and it doesn’t even notice it’s there,” Mr McNoldy said.<\/p>\n
It hit Jamaica as a category five storm with winds of up to 225 kph, but after crossing the island relatively quickly, weakened to category three.<\/p>\n
The third ingredient that normally slows a hurricane down is the deeper, colder water that gets dragged up from below when it has been sitting in the same spot for a while.<\/p>\n