How SeaTrees Chooses the Best Carbon Offset Projects

You might have noticed that the subject of carbon offsets has been a “hot” topic in 2023. Particularly according to a critical article published in The Guardian.

This article was immediately criticized for using faulty science, and offsets are still a key part of reversing climate change.  Let's unpack this and explain our approach to choosing the best carbon offsets as part of a larger sustainability strategy.

The team at SeaTrees has a long history of working in and around carbon markets, so let us provide some clarity around this very complicated subject.

Nature-based Carbon Offsets Are Crucial To Reverse Climate Change

When the subject of offsets comes up, it is natural to ask whether we should just reduce CO2 emissions in the first place, and only purchase offsets as a last resort.  This would be a valid approach, if you are asking the question in 1997 when the first global treaty on climate change was signed. 

The 1997 Kyoto Protocol defined how countries should reduce emissions and was signed by most of the world’s countries. It also defined the principle of carbon offsets and cap and trade as a “market mechanism” that would speed up emissions reductions in a fair and equitable manner. 

If the world’s countries had reduced emissions reductions as planned, carbon offsets would have been a minor but helpful part of the overall solution to climate change. But that didn’t happen, and now in 2023 we’re in a crisis that needs a new way of thinking.

Unfortunately, the Earth’s climate system has passed multiple tipping points, and now we need to remove CO2 from the atmosphere as fast as possible. This will help reverse tipping points while the world figures out how to reduce CO2 emissions.  

To reverse climate tipping points, we’re believers in the Net-Zero approach to climate change, which places equal importance on both emissions reductions and atmospheric CO2 removals. We wrote about this in 2021, when renowned climate scientist, Dr. Michael Mann, said that Net-Zero is a necessary strategy to avoid climate disaster. 

To achieve Net-Zero today, a company is required to both reduce CO2 emissions as fast as possible, and also purchase carbon offsets for the remainder. The preferred offset choices are termed “nature based” which restore and protect natural ecosystems that sequester CO2 through the action of photosynthesis. 

The Choice of Carbon Offsets Matters Greatly

The “market” for carbon sequestration is simply not the same as typical markets, where a purchase results in a tangible good or service being provided. Instead, carbon offsets represent the removal of a ton of carbon dioxide gas, which is extremely intangible and hard to comprehend. 

Thus a highly complex system of checks and balances has been created to verify that a climate benefit is produced by money spent. While it’s easy to get lost in carbon market terms like “additionality”, “baseline” and “methodology”, it’s also quite easy to spot good candidates for the best carbon offset projects. 

Quite simply, the best nature-based carbon offset projects produce benefits for the local communities and ecosystems.  The removal of CO2 is a side-benefit from protecting biodiversity and conducting sustainable development for communities in need.

For our choice of certified carbon offsets, we work with the Southern Cardamom REDD+ Project in Cambodia. This is one of the highest quality carbon sequestration projects in the world, and it protects mangrove forests and coral reefs at the base of watersheds in the Cardamom Mountains. Thus we consider it “blue carbon adjacent”, and an excellent foundation for a net-zero strategy.  

The Southern Cardamom REDD+ Project incorporates local indigenous knowledge to protect 497,000 hectares of coastal watershed in Cambodia. This "Ridge to Reef" project is key to conserving the Indo-Burma Hotspot, one of the most biologically important regions on the planet. 

Additionally, the project creates over 1,000 jobs for local community members, improves education and healthcare for over 16,000 individuals, and provides sustainable livelihoods for over 20 villages.

It protects 35 IUCN Red List endangered species, including bengal tigers and asian elephants. You can see how the project works by visiting one of the many eco-lodges, and supporting eco-tourism which is a sustainable source of income for the community.

One of the main criticisms of REDD+ projects is that the threat of deforestation is overestimated. This is definitely not the case in Cambodia, which has one of the highest rates of illegal logging in the world. Since the project began in 2013, it has conducted 29,000 patrols, confiscated 6,808 chainsaws, 29,422 illegal logs, 16,440 illegal fences/signs, and 208,231 animal snares by employing a team of rangers and community members to protect the forest against loggers and poachers.


A recent open letter from the Global South emphasizes the significant benefits that properly implemented REDD+ projects bring to local communities. Local communities and stakeholders have generations of knowledge and expertise that should be in good project design. This is why we stand by our choice of the Southern Cardamom REDD+ Project, which serves as a testament to successful offset projects, sequestering millions of tons of carbon dioxide over its lifespan, and protecting one of our planet's most diverse and precious ecosystems.

Making Sense of Criticism from The Guardian and Others

The complexity described above leaves carbon offset projects vulnerable to attack. Even if the attacks are misguided, it’s very hard to parse out why.  

In the case of The Guardian articles, their criticism revolves around how a carbon offset project sets a “baseline” condition that is used to quantify the net carbon benefit of the project each year. The Guardian claims that REDD+ projects overestimate the rate of deforestation, and thus claim carbon credits for protecting forests that are not under threat. 

Unfortunately, The Guardian based these claims on faulty science that was immediately criticized as soon as the article was published. The faulty science was not peer-reviewed and tried to simplify baseline calculations by ignoring on-the-ground knowledge of local deforestation conditions. This is why we highlight the local conditions of the Southern Cardamom REDD+ project, including the high rate of illegal logging and confiscated chainsaws.

Thus we strongly disagree with the conclusion that 90% of forest carbon offsets are worthless.  This is a highly negative viewpoint that has been consistently promulgated in The Guardian in recent years, and shows no sign of changing in the future.  

For a more detailed discussion on critiques of The Guardian article, see statements by Verra, Everland, and many others.

Language Around Carbon Offsets Matters More Than You Think

In general, SeaTrees avoids the use of the word “offset” in our communications. This blog post is an exception. We believe the term offset connotes a frame of “paying for the sin of CO2 emission”.  That frame immediately suggests that it is better to just not emit CO2 in the first place and “offsetting” means covering up that sin.   

We prefer language like “taking responsibility for your climate impact”, which connotes a proactive approach that includes both emissions reductions and nature-based carbon sequestration.  This is what is needed to reverse the climate crisis and achieve net-zero emissions.

In the near future, we will be producing more articles and content that expands on the points made in this blog post.