Our expert guest offers his evaluation of a recent investigation by British media outlet The Guardian.

Synopsis: Every first and third Monday of the month, The Straits Times analyses the beat of the changing environment, from biodiversity conservation to climate change.

Forests are one of nature’s ways of soaking up large amounts of carbon dioxide (CO2), helping apply the brakes to climate change. This explains why halting deforestation and replanting forests makes sense. Investors who do this, want to earn a return for their efforts by selling tradeable “offsets” representing a tonne of CO2 removed, or avoided from being emitted, such as protecting a forest under threat from clearing.

Forest carbon offsets have become big business, helping offset buyers to reduce their carbon footprint and meet their climate targets, in addition to other carbon-cutting steps that they must take. But rainforest carbon offsets are controversial because of concerns over the quality of the credits and projects and whether the forests will really remain standing for the long term. And do these projects really lead to big reductions in deforestation?

The issue has come to the fore after a recent investigation by The Guardian, which concluded that rainforest carbon offsets issued by Verra, the world's main certification body for offsets, were mostly worthless. Though widely panned as being flawed, the conclusions by The Guardian have highlighted the need for further tightening of the standards and scrutiny of forest carbon offsets.

In this episode, ST's climate editor David Fogarty hosts Professor Koh Lian Pin - director of the National University of Singapore’s (NUS) Centre for Nature-based Climate Solutions - who has been working to boost the integrity of nature-based carbon offset projects. He looks at the pros and cons of rainforest carbon offsets.