Maintaining healthy biodiversity can play a significant role in climate change mitigation and the world’s protected areas - national parks, marine reserves, wilderness areas and so on - are essential in safeguarding this role.
Already, protected areas through the vegetation they contain, store 15% of the world’s terrestrial carbon. They have enormous untapped potential considering that as much as 20% of greenhouse gas emissions come from deforestation and other land use changes. Through active restoration of forests or mangroves and through natural regeneration within protected areas, the ability of protected areas to store carbon can be significantly increased. Multiple benefits can be seen on the ground: protected areas in the Brazilian Amazon are likely to prevent an estimated 670,000 km² of deforestation by 2050, representing 8 billion t of avoided CO², and in Bolivia, Mexico and Venezuela, protected areas contain 25 million ha of forests, storing over 4 billion t of carbon, worth between USD 39 and 87 billion.
By safeguarding the health of ecosystems, protected areas also help us respond to and reduce the risks of climatic disasters which, with 60% of global ecosystem services already degraded, are becoming more frequent. Protected areas provide space for floodwaters to disperse; their ability to stabilize soil can prevent or slow landslides; strengthened coastal ecosystems provide a buffer to storms, and limiting human encroachment into fire-prone areas can reduce the number of wild fires.
Protected areas also help maintain the ecosystem services on which we depend including water purification, protection of fish stocks, other food resources and traditional medicines. Again, wide-ranging benefits can already be seen: 33 of the world’s 105 largest cities derive their drinking water from forest protected areas and in Kenya, coral reef protection has resulted in improved fishery health, bringing economic benefits to local people.