BONN, Germany - Many nations have become less vulnerable to natural disasters ranging from cyclones to earthquakes because of improved preparedness, but Pacific island states remain most at risk, a study showed on Tuesday.

Climate change is raising risks by increasing the numbers of severe downpours, storm surges or heat waves, according to the report issued on the sidelines of U.N. talks on climate change in Germany.

But "on a global scale, vulnerability to extreme natural hazards has declined," said Peter Mucke, director of the World Risk Report and head of Bündnis Entwicklung Hilft, an alliance of German aid agencies.

"Many countries have learnt from previous disasters and are improving disaster preparedness," he said of the findings in the annual report, published with the U.N. University and other groups.

The report assesses the risks that an extreme natural event will lead to a disaster in 171 nations in the period 2012-16. It listed Vanuatu, Tonga, the Philippines, Guatemala, Bangladesh, Solomon Islands and Costa Rica as the most vulnerable.

Fiji, which is presiding over a Nov. 6-17 meeting in Bonn on ways to strengthen the 2015 Paris climate agreement, ranked 15th most vulnerable. As a region, Europe was least vulnerable.

The report said there were many ways to make societies less vulnerable to disasters, from cyclone shelters to flood barriers on rivers. "Mangroves can reduce flood risks to people and property," said Michael Beck of the Nature Conservancy.

The report assesses both risks such as from storms, where rising sea levels linked to melting glaciers play a role, and earthquakes and tsunamis that are unaffected by man-made climate change.