Climate change is the biggest potential threat to natural World Heritage sites, but these sites can be part of the solution
Impact on natural World Heritage sites
According to the IUCN World Heritage Outlook – the first global assessment of natural World Heritage – climate change could soon become the most widespread threat to natural World Heritage sites. in 2014, climate change impact was already evident in 35 sites listed for their exceptional natural values (out of 238 in total as of 2016).
While only coordinated global efforts can help address the threat of climate change, it is important to increase resilience of threatened sites by limiting other pressures to a minimum.
Marine and coastal sites are facing particular challenges due to sea level rise, ocean acidification, and increased frequency and severity of extreme weather events. In Australia’s Great Barrier Reef – the world’s largest coral reef system – rising water temperatures are causing coral bleaching, and ocean acidification is restricting coral growth and survival. In East Rennell, Solomon Islands, a World Heritage site listed as ‘in danger’ due to logging activities, the increasing salinity of Lake Tegano as a result of sea level rise has caused reduced freshwater supply and food shortages for the local communities.
Nature-based solutions to climate change
Natural World Heritage sites are not just iconic places with exceptional nature, they also provide benefits that contribute to human well-being, according to ‘The Benefits of Natural World Heritage’ study by IUCN and UNEP’s World Conservation Monitoring Centre.
Natural World Heritage sites contribute to global climate stability by storing significant amounts of carbon. Forests found in World Heritage sites across the tropical regions store 5.7 billion tons of carbon.
Two-thirds of natural sites on the UNESCO World Heritage List are crucial sources of water and about half help prevent natural disasters such as floods or landslides.
In India and Bangladesh, the Sundarbans’ 2,200km mangrove coastline offers flood protection, which would otherwise require an investment of US$ 300 million in man-made infrastructure.
The Benefits report features a total of 23 case studies, including three which highlight how World Heritage sites contribute to responding to climate change:
- Sundarbans National Park (India) and The Sundarbans (Bangladesh)
- Ibiza, Biodiversity and Nature (Spain)
- Canadian Rocky Mountain Parks (Canada)
A wilderness approach to help respond to climate change
IUCN's 2017 report, “World Heritage, Wilderness, and Large Landscapes and Seascapes”, argues that protecting large intact land- and seascapes is a crucial strategy to address climate change and biodiversity loss, as these irreplaceable areas provide greater benefits and host more plant and animal species than smaller, more disturbed areas.
Natural World Heritage sites often include very large areas: the 241 sites listed for their natural values account for 8% of the total surface covered by all 230,000+ protected areas worldwide. Large sites with wilderness values include iconic places such as the Galapagos Islands in Ecuador, Yellowstone National Park in the USA and the Okavango Delta in Botswana.
Wilderness areas help respond to climate change, for instance stocking huge amounts of carbon and serving as refuge for species which are forced to migrate due to a changing climate. However, they are also under severe threat from climate change, and are continuously being cleared, degraded and fragmented, largely due to industrial activities such as oil and gas extraction, mining, logging, agriculture, construction of roads and dams. The wilderness left on land now covers less than a quarter of Earth’s total land surface.
On land, natural World Heritage sites cover 1.8% of the world’s remaining wilderness area, while at sea 0.9% of marine wilderness has World Heritage status. The World Heritage Convention can do more to protect wilderness. Providing guidance on how this can be achieved, the report identifies broad gaps in the World Heritage List’s wilderness coverage.