But while we are looking up at the treetops for climate solutions, some campaigners are urging the world to look down, where another answer lies -- right under our feet.
Forests, peatlands, deserts and tundra can all absorb and hold stocks of carbon-dioxide (CO2). Of all the carbon held in land-based ecosystems, around 34% can be found in grasslands, data from the World Resources Institute show
. That's not much less than the 39% held in forests.
"Whether you look at the Serengeti, the Cerrado in Brazil, whether you look at what's left of the prairies in North America or the steppes of Mongolia -- every single one of our major, iconic grassland habitats is under threat at the moment," Ian Dunn, chief executive of the British conservation organization Plantlife, told CNN.
There's also plenty of it in the United Kingdom, which will host world leaders and climate negotiators in just over a week at the COP26 climate talks in Glasgow, Scotland. Among several items on the agenda is how to protect forests and plant more trees to help slash global emissions.
But Plantlife, among other groups,
is campaigning for grasslands to be protected at an international level and part of any deal that emerges in Glasgow.
While leaders meet in the Scottish city, Plantlife is working to restore more than 100,000 hectares of meadows, including one on the other side of the United Kingdom, in the southern English county of Kent.
The Ranscombe Farm Nature Reserve looks just like your typical patch of English countryside, with its soft rolling hills and grazing cattle. The grass here looks ordinary, browned in patches from the autumn weather. But come spring, the rare orchids, bellflowers and rock roses will bloom in a celebration of this grassland's biodiversity.
Restoring species-rich ecosystems like this takes time, said Ben Sweeney, Ranscombe Farm's manager, who has been working on this grassland since 2010.
"It will take a couple of decades," he said.
Ranscombe Farm protects not only grasslands but also woodlands, rough grazing pastures and crop fields for rare plants.
Sweeney explains that just like with an animal sanctuary, Ranscombe Farm nurtures rare plants in small sections of the reserve, where they are thriving, and can hopefully grow and spread out into bigger habitats soon.
But even after years of careful management, rangers have not been able to reverse all the impacts that farming and land degradation have had on the site.
In the UK, these vital habitats have been slowly disappearing as a consequence of decades of intensive agriculture, housing development, and infrastructure build-up over the last century. The UK has lost more than 2 million acres of grasslands
as urban and woodland areas expand, according to the UK Center of Ecology & Hydrology.
That concerns activists, because grasslands not only store carbon but also serve as a buffer for extreme weather and help prevent soil erosion. Their roots hold together light soil, and the ground cover prevents erosion from wind and water. These habitats help with natural flood management by holding water after extreme weather events, then releasing it gradually.
The loss of grasslands also threatens the important species that rely on them, like bees, butterflies and other pollinators.
A recent study published by the University of Manchester
revealed the UK's grasslands store more than 1.8 billion metric tons of carbon. That's the equivalent of storing the yearly emissions from about 400 million cars.
"But they are pretty much ignored or have been ignored in many sustainability policies," said soil expert and ecology professor Richard Bardgett, the study's lead researcher.
, published in 2018 in IOP Science, concluded that grasslands in California could play a bigger role than forests as carbon sinks, as they are less vulnerable to fires and drought, which parts of the world will experience more of as the Earth continues to warm. That's because grasslands keep most of their carbon locked in their roots underground -- even during drought and fire -- unlike forests, in which carbon is spread up and throughout trees.
Your diet could be linked to grassland destruction
When managed poorly, grasslands can become a net source of emissions
, rather than a sink to remove them. Rearing livestock on grassland, too, plays a major role in methane emissions, which is also contributing to the climate crisis.
A global increase in demand for meat and dairy products, as well as soy, is putting pressure on grasslands.
The world's most biodiverse savanna, the Cerrado in Brazil, has been reduced to around half its original size, mainly for the expansion of beef and soy production, according to the World Wide Fund for Nature
(WWF), which says the Cerrado loses an area equivalent to the size of São Paulo every three months.
In China, vast expanses of grasslands are in a "state of ecological crisis," according to scientists, caused by overgrazing of the land. Meanwhile, in the United States, the expansion of farmland has led to the prairies of the Great Plains losing an average four football fields every minute, according to a WWF report published in 2020.
While grassland protection is a global concern, there are growing expectations for the UK to show climate leadership ahead of COP26.
Campaigners are disappointed with the omission of grasslands as a nature-based solution in the government's Net Zero Strategy, which is being seen as a potential blueprint for other nations' climate roadmaps.