About two billion tonnes of carbon dioxide are being removed from the atmosphere every year, according to a report published on Thursday, but nearly all of it is accomplished through forests, despite growing investments in new technologies.

The independent report, led by the University of Oxford, is the first to assess how much CO2 removal the world is already achieving - and how much more is needed.

It estimates that roughly 1,300 times more carbon dioxide removal from new technologies — and twice as much from trees and soils — are needed by 2050 to limit temperatures to well below 2 degrees Celsius above pre-industrial temperatures, as set out in the Paris Agreement.

"CO2 removal is rapidly moving up agendas," said report co-author Steve Smith, a climate scientist at the University of Oxford. But he said that despite growing interest and investment, "there are major gaps in information".

CO2 removal involves capturing the greenhouse gas from the atmosphere and storing it for a long period of time either on land, in the ocean, in geological formations or in products.To date, almost all successful CO2 removal has been achieved through measures like planting trees and better managing soils.

From 2020 to 2022, global investment in new CO2 removal capacity totalled around $200 million, according to the report, while some $4 billion has been funnelled into publicly-funded research and development since 2010.

Although countries aren't currently planning to use CO2 removal to meet short-term climate goals by 2030, many envision it as part of their strategy for reaching net zero by 2050.

Report co-author Jan Minx, of the Mercator Research Institute on Global Commons and Climate Change in Germany, said that while reducing emissions remains the top priority for reaching the Paris goal, "at the same time, we need to also aggressively develop and scale up CO2 removal, particularly those novel methods."

He added that would take time as "we are still at the very start".

Last December, the US Department of Energy committed $3.7 billion to finance CO2 removal projects. And the European Union aims to capture five million tonnes of CO2 annually by 2030.