Last month, nine philanthropic organizations pledged $5 billion to protect 30% of the planet over the next decade — the largest commitment of private funding ever made for the conservation of nature. These organizations intend to address three interrelated global crises — the climate crisis, the biodiversity crisis and the public health crisis — while working with Indigenous Peoples and local communities. 

The pledges arrive not a moment too soon. A new report released on October 28, 2021 by WRI, the United Nations Educational, Scientific and Cultural Organization (UNESCO), and the International Union for Conservation of Nature (IUCN) reveals that despite substantial carbon stored and absorbed by forests across UNESCO’s World Heritage network, the climate benefits of even some of the world’s most iconic and protected places are under pressure from land use and climate change. Continued reliance on these forests’ carbon sinks and storage depends upon stronger protection measures.

UNESCO World Heritage Sites Provide Valuable Benefits to People and Nature

Since its adoption in 1972, the World Heritage Convention has encouraged the identification and preservation of unique cultural and natural heritage sites around the world considered to be of “Outstanding Universal Value” to humanity. By signing the Convention, countries pledge to conserve not only the World Heritage sites situated on their territory, but also to protect their national heritage. 

Today, there are 1,154 sites inscribed on the UNESCO World Heritage List, nearly one quarter of which are included specifically for their natural values or combination of natural and cultural values, and many contain large or unique forest ecosystems. Across these 257 natural World Heritage sites, forests cover an area twice the size of Germany, protecting unique biodiversity and providing multiple goods and services benefitting people across the planet. For example, the total value of the ecosystem services and benefits provided by Virunga National Park in the Democratic Republic of the Congo is estimated to be almost $49 million a year. 

Newly available maps on Global Forest Watch (GFW) provide spatially detailed data that enable us to better quantify one of these ecosystem services — carbon sequestration — by determining how much carbon these protected areas absorb from and release into the atmosphere each year. UNESCO, WRI and IUCN combined data from GFW with on the ground reports about World Heritage sites to tell the carbon story of World Heritage forests over the past 20 years. 

World Heritage Forests Are Strong Carbon Sinks

The new analysis shows that trees and forest soils across UNESCO’s 257 natural World Heritage sites hold a wealth of carbon — an estimated 13 billion metric tonnes. For comparison, the carbon stored in vegetation and soils at these World Heritage sites exceeds the amount of carbon in Kuwait’s 101 billion barrels of proven oil reserves.

It took centuries for these forests to accumulate the carbon they currently store, and they’re not done. As forests grow, they naturally sequester more carbon by photosynthesis than they release by respiration — making them carbon sinks — even into very old age. Between 2001 and 2020, forests across World Heritage sites removed enough carbon from the atmosphere every year (190 million tonnes of carbon dioxide per year) to counterbalance about half of the United Kingdom’s annual carbon emissions from fossil fuels. 

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The joint report finds that just 10 large sites were responsible for half of the World Heritage network’s net carbon sink, but smaller sites that absorb carbon dioxide at high rates per hectare can have considerable climate benefits. In fact, the average hectare of World Heritage forest within 55 of the sites can absorb the same amount of carbon that a passenger vehicle emits in a year.

But Protected Forests’ Ability to Absorb and Store Carbon is Under Threat 

The analysis wasn’t all good news. At least 10 sites within the World Heritage network were net carbon sources between 2001 and 2020, meaning they emitted more carbon than they absorbed during this period due to a variety of disturbances. And other sites, despite remaining net carbon sinks overall, showed spikes or clear upward trajectories in emissions that threaten the strength of the future sink. Given the global recognition and protected status of World Heritage sites, this level of emissions from sites is both unexpected and alarming. 

According to the state of conservation reporting process of the World Heritage Convention and the IUCN World Heritage Outlook 2020, two widespread threats are likely responsible for the surprising level of emissions at many of these sites: land use pressures and severe fires. 

Land use pressures including illegal logging, livestock grazing and cultivation of crops reportedly occurred across about two thirds of all UNESCO natural and mixed World Heritage sites over these two decades. For example, illegal logging and clearing in Virunga National Park in the Democratic Republic of the Congo has intensified due to the demand for charcoal and timber by the growing population adjacent to the park, many of whom are refugees from conflicts. At the extreme, logging and agricultural clearing at sites like the Tropical Rainforest Heritage of Sumatra in Indonesia has been so intense that carbon emissions have exceeded carbon removals over the past twenty years. 

Even sites relatively free from direct land use pressures are turning into net carbon sources under climate change. Sites in Siberia and Australia experienced emissions from wildfires that spiked beyond 30 million metric tonnes of carbon dioxide in a single year, higher than the annual fossil fuel emissions of many countries. Fires have also become severe where they were traditionally rare or absent, such as in Bolivia’s Noel Kempff Mercado National Park, where more area was burned in 2020 than in any year since 2001. Most fires in World Heritage sites originate in and escape from surrounding lands, but a changing climate brings higher temperatures and winds, shifts in the dry season and more fires occurring later in the year, causing fires to spread further into neighboring forests.

As climate change causes wildfires to intensify, forests’ ability to fully recover from such events in the future may be hampered, leading to emissions spikes in the short term and reduced capacity for carbon sequestration in the longer term, thus reducing overall carbon storage.

3 Pathways to Protect World Heritage Sites and Maintain Their Climate Benefits 

World Heritage forests supply critical climate benefits that must not be taken for granted; continued sequestration of atmospheric carbon dioxide by forests at these sites requires vigilance. At some sites, emissions from local human pressures have increased; at others, climate change puts sites’ carbon stores and ongoing capture at risk. While diverse interventions are needed to address all threats, three distinct pathways for action emerge to secure World Heritage forests as sustained carbon sinks for future generations. 

1. Develop Rapid Response Systems for Climate Emergencies

Some forest fires can be beneficial: They can kill diseases and insects that prey on trees, provide valuable nutrients that enrich the soil, and bring sunlight to tree seedlings on the forest floor. However, rapid response is integral to preventing fires from developing into conflagrations (boundless and extremely destructive fires) that produce extensive emissions, especially with fires becoming more frequent and severe. By using near-real-time tools like fire alert data on GFW, government agencies in Indonesia have shown that it’s possible to reduce fire response time by 80%, from 30 hours or more down to just two to four hours. 

2. Strengthen and Maintain Landscapes that Surround Forest Sites

Protecting sites’ broader landscapes protects the sites themselves. Most pressures to World Heritage sites originate outside their boundaries, where forest protection is weaker. Integrated landscape management and creation of ecological corridors and buffer zones are therefore necessary to ensure that sites’ integrity, and ability to store and sequester carbon, is preserved. 

For example, ecological connectivity between the Dja Faunal Reserve in Africa’s Congo Basin and the closest other protected area is threatened by forest clearing for urban development, agricultural activity and roads in between. In addition to increased carbon emissions, the fragmentation of the forest landscape around the site impedes the movement of keystone species such as forest elephants, which perform ecological functions like seed dispersal that maintain the forest’s plant community structure over time. In contrast, at Sangha Trinational forest located within Cameroon, the Central African Republic and the Republic of Congo, the creation of a buffer zone has kept some human activity farther from the site. In addition to adding a layer of protection to sites, buffer zones can act as valuable net carbon sinks. For example, the net carbon sink of Sangha Trinational buffer zone is more than twice as large as that of the site itself. 

3. Integrate Protection of World Heritage Sites into Achieving International Agreements

Explicitly including World Heritage sites in countries’ plans to meet international agreements — such as Sustainable Development Goals, climate action plans (or Nationally Determined Contributions), and biodiversity strategies under the Post-2020 Global Biodiversity Framework — can help leverage the multiple values of World Heritage sites. Plus, integrating sites into such agreements is a win-win: if a World Heritage site‘s protection is a key element of the agreement goal, efforts to achieve the goal should inherently protect the site. 

Moreover, World Heritage forests can be at the forefront of efforts to recognize local communities as effective stewards of forests, which is an important aspect of achieving an internationally recognized, comprehensive framework to halt deforestation and compliance with the International Bill of Human Rights. For example, after coming under recent pressure from mining and logging, a cooperative management between Indigenous Peoples and the local government was established in the Wet Tropics of Queensland World Heritage site in Australia, thus publicly acknowledging the community’s rights to own and sustainably manage their land. 

Conserving Global Forests Is a Strong Climate Solution

Across the world, changes to the global climate system are causing unprecedented local impacts, such as severe fires, heatwaves, droughts and floods. The new analysis of UNESCO World Heritage sites shows that forests are a climate solution. 

Local actions taken today to protect forests can mitigate climate change and help reverse its current trajectory. Combining GFW’s global forest carbon data with on-the-ground information can build awareness of these linkages and help improve local accountability towards achieving global climate goals.