Tropical storms have again been in the news after Cyclone Pam wrought devastation through the Pacific islands, most notably the island communities of Vanuatu, and caused an unprecedented three-day delay in the start of leg five of the Volvo Ocean Race.

Climate change models predict more extreme weather events, whether that’s the prolonged heavy snow that blanketed parts of the USA this winter, or tropical storms, hurricanes or cyclones.

Climate change: cyclone and hurricane strengths affected

Cyclone Pam closes in on the Volvo fleet in harbour at Aukland New Zealand after wreaking havoc across the Pacific with gusts of wind recorded over 200mph. (Image: Volvo Ocean Race)



Professor Tim Palmer, director of the programme on modeling and predicting climate at Oxford University told BBC Radio 4: “…these incredibly intense tropical cyclones – not just Pam, which hit Vanuatu, but also Haiyan which hit the Philippines last winter – are producing record-breaking winds. It’s exactly this type of extreme cyclone that is predicted by the climate models to increase under climate change.

“Within the class of all tropical cyclones we’re now seeing storms with wind strengths and gusts that have never been measured before – 200 plus mile per hour winds. This is coupled to an exceptionally warm tropical Pacific sea temperature – sea temperatures in the Western Pacific are at their warmest since records began. This is also almost certainly coupled to the very extreme temperatures that Australia has seen as well.

“It’s a pattern that’s all consistent with the general trend that the models predict to be occurring under climate change. It’s also important to say that it’s a complex picture – the climate models say that the [the number of] tropical cyclones in totality will decrease – but what they do say is that the very extreme type of tropical cyclone like Haiyan and cyclone Pam are likely to increase – and this is what we’re seeing.”

This issue is also one that will affect sailors in tropical waters of the northern hemisphere, including the Caribbean, the southern states of the USA and Mexico’s Pacific coast, where cyclones are referred to as tropical storms or hurricanes.

For more stories on extreme weather, see: Britain’s deadliest storms remembered and Sailing survivors: five extraordinary ocean voyages.