Iconic monuments, glorious national parks and colorful coral reefs are all in danger of being wiped off the map as rising sea levels, increasing temperatures and intensive storms take hold due to climate change.
The Bwindi Impenetrable Forest National park in Uganda, Italy's "floating" city of Venice, and Yellowstone National Park in the United States are among the natural and manmade treasures at risk from climate change, according to the report "World Heritage and Tourism in a Changing Climate" released on Thursday (25.05.2016).
"If we don't do something to reduce our greenhouse emissions, we will lose some of our world heritage and future generations won't be able to see it," Adam Markham, deputy director for climate and energy at the Union of Concerned Scientists (UCS), and one of the authors of the report, told DW.
A UCS collaboration with the United Nations Educational, Scientific and Cultural Organization (UNESCO) and the UN Environment Program (UNEP), the report reviewed 31 World Heritage Sites in 29 countries. As well as reporting on possible damage to the sites themselves, the document details the potential impact to tourism - which could be particularly detrimental to less developed countries, Markham pointed out.
"If damage occurs to these places then the reasons people visit them will becomes less and less … this could be very harmful to the local economies that depend on tourists," he said.
The Wadden Sea World Heritage Site consists of the largest unbroken stretch of sand- and mudflats in the world, stretching across the shores of the Netherlands, Germany and Denmark. With a diversity of wildlife, it draws around 10 million visitors each year and brings in an estimated 3 to 5 billion euros in revenue, according to the report.
But the site is threatened by rising sea levels and increasing storms. There have already been problems for breeding birds that may be associated with climate change.
"We are already having more storms, and earlier, which is impacting some breeding birds. Their chicks are being drowned when they are still too small to fly," Folkert de Jong, deputy secretary of the Common Wadden Sea Secretariat, told DW.
Disappearing land as a result of rising sea levels could also force birds foraging in the area to look for food elsewhere, while sandy beaches on the Wadden Sea's islands could vanish under water. Although it is difficult to predict the reaction of tourists, all this is likely to reduce the site's appeal.
Many World Heritage sites are a key attraction for tourism and important to local economies. Chile's Easter Island, home to the giant-headed "moai" statues, is dependent on the 60,000 tourists who visit each year, while gorilla trekking in Bwindi Impenetrable National Park brings in Uganda's highest tourism-related revenue, at $20 million to $46 every year.
Globally, tourism is one of the largest and fastest growing sectors. It generates 9 percent of the world's gross domestic product and accounts for one in every 11 jobs. And tourism is already being hit by changing weather patterns, says Stefan Gössling, a professor of service management and service studies at Lund University in Sweden, who has written extensively on the relationship between climate change and tourism.
"Many destinations depend on stable climate conditions. The most important threat is changes in rainfall patterns, which can really spoil a holiday," he told DW.
In the long term, however, he said, there could be more significant impacts on locations such as World Heritage sites and other popular destinations.
De Jong said most effects of climate change on the Wadden Sea would not be felt for another 50 to 100 years. Still, measures have already been taken to strengthen dykes to prevent the impact. Further adaption efforts, such as adding sand to beaches at the park's islands, are also planned.
But Gössling said he didn't think there was a strong need for adaptation measures to be taken now.
Venice has already experienced flooding in recent years, but things could get worse as a result of global warming
"I don't think there's an immediate need to start preparing for the future - the change will be gradual." Measures to prevent a global temperature rise of up to 4 degrees Centigrade are more pressing, he said, adding: "That would be the end of tourism to a large degree."
Time to act
Still, the irony of a report on disappearing World Heritage, said Gössling, as that it is likely to encourage more people to visit the sites, meaning more travel by plane or other transport - and ultimately, further contributions to climate change.
"People are seeking out - and thereby destroying - the very destinations they are trying to preserve," he said.
Tourism itself is energy-intensive. It contributes around 5 percent to global carbon emissions, and is expected to more than double in the next 25 years. Aviation accounts for approximately 40 percent of the CO2 emissions attributed to tourism, with cars making up another 30 percent.
But Gösling said that he doesn't advocate people stopping traveling altogether. "I would be very happy if people chose destinations that are closer to home - or if they stayed [at distant destinations] for a longer period of time to help reduce the impact from travel."
Meanwhile, Markham said although we are only just learning about future effects of climate change, we need to act now. If governments implement the Paris Agreement, there is a "real chance to slow down global warming and to reduce the impact," he said.
"Almost all World Heritage Sites are being affected in some way - climate change is here, and it's getting worse."