What Is: Carbon Offsetting with a Blue Carbon Project
This article is a brief description of carbon offsetting through projects related to blue carbon, which are nature-based projects related to aquatic ecosystems. It is for someone intending to offset their carbon footprint, providing the basics for how these projects achieve carbon offsetting, what carbon accreditation auditors look at when evaluating them, and issues commonly associated with them.
For preparatory reading, and links to other articles in this Carbon Offsetting series:
- Carbon Offsetting & Net Zero Carbon Emissions
- Blue Carbon Offsetting Projects
- Are there blue carbon offsetting projects?
- Further reading:
Carbon Offsetting & Net Zero Carbon Emissions
Since the global warming phenomenon was first confirmed in the 1990s, the need to scale back greenhouse gas emissions has been known.
Greenhouse gases have increased at an unprecedented rate in planetary history, driven by mankind's burning of fossil fuels within a relatively short period of time. The increased heat trapped by the added greenhouse gases have begun to change the balance of climate systems, some of which lead to the release of even more greenhouse gases (e.g. forest fires, permafrost melts).
In 2015, the Paris Agreement saw the nations of the world agree that global warming needs to be kept below 2 degrees above pre-industrial global temperatures (aiming for no more than 1.5 degrees to avert the worst effects of climate change to vulnerable nations).
Net zero carbon emissions is not about that.
Well, yes, and also no.
You may have noticed a growing number of companies pledging to have 'net zero' or 'net neutral' carbon emissions. Invariably this will involve changing the way their businesses operate so that they are less carbon intensive. (And, if there are any carbon emissions left over, they have to be offset through carbon removal projects.)
However, without needing to be particularly good in math, you would realise that even if all businesses are net neutral, the planet would still not be in carbon balance. The greenhouse gases already in the atmosphere now will continue to heat the earth, and climate change that is already underway will release other greenhouse gases from natural reserves.
So this is why I say upfront that going net zero is not about solving climate change per se. Additional things have to be done over and above that. Going net zero is more about not making the problem worse, so that it doesn't constantly become harder and harder to solve.
It's sort of like being trapped in a terrible job. It's a lot harder to find a better job, and pay down your debts, if you keep spending more and more.
Carbon offsetting verification standards
Carbon projects rely on carbon accounting to qualify as a carbon offsetting project. (Jargon cheat sheet article link is at the top).
Carbon projects may be fully dedicated to a company intending to meet net neutral targets (e.g. Qantas' reforestation project), or open for individual voluntary carbon offsetters (like you and I). The latter are usually managed by carbon offsetting service providers such as Terrapass.
Like financial accounting, you need audits to make sure the carbon accounting is honest. Unlike financial accounting, which has been around for longer, carbon accounting is still being tweaked to close its gaps, since is it still a relatively new discipline. That this is still going on, does not mean that carbon accounting isn't trustworthy, or that it isn't essential.
For individual offsetters, we can rely on audits carried out by the service providers to be assured that projects are managed in accordance to standards recognised by the United Nations Framework Convention on Climate Change (UNFCCC). Examples include the Gold Standard, and the Verified Carbon Standard.
Blue Carbon Offsetting Projects
OK, with the context out of the way, now on to the project type. This article will cover blue carbon projects and touch on the ones that now qualify for carbon credit funding.
What are blue carbon ecosystems?
When we think about nature-based carbon storage, forests on land come to mind. After all, most cultures are continental. And besides, forests are known to cover huge areas.
However, countries with long shorelines are more familiar with coastal ecosystems. Despite being present only in a narrow strip of coastal land, these ecosystems range from forest (mangroves) to grassland (salt marsh). And if you actually go offshore, as island nations would know, there are seagrass meadows and kelp forests underwater.
All of these marine ecosystems also store carbon. The carbon stored through these ecosystems are termed 'blue carbon' to distinguish them from those stored by terrestrial ecosystems.
What is the difference between blue carbon and terrestrial stored carbon?
Why is it necessary to distinguish between the two? While part of it is to draw attention to the potential of these undervalued ecosystems, there's also a more practical reason.
Coastal and marine ecosystems harbour different processes that influence the way carbon cycles through, and whether it gets stored or emitted. Additionally, carbon enters the ecosystem in more ways. Blue carbon ecosystems absorb carbon dioxide in the form of gas during photosynthesis in the way that terrestrial forests would. But carbon also enters the ecosystem through water flows.
Therefore, blue carbon balance is more dynamic than forests.
How do blue carbon ecosystems combat climate change?
Up until recently, the mainstream view was that coastal ecosystems are not important in climate action at all. In fact, wetlands were thought to be natural carbon sources, because the waterlogged conditions favour anaerobic degradation, which generates methane. Methane, of course, is an even more potent greenhouse gas than carbon dioxide.
However, research in recent years have discovered that - despite the methane generation - coastal ecosystems sequester and store large quantities of carbon. For example, mangroves can store between 3-5 times more carbon than tropical forests, and can continue doing so for longer. Protecting and restoring mangrove ecosystems alone can mitigate 108 million metric tonnes of CO2e per year.
The reason for this is because mangroves do not just store carbon in woody biomass. They also trap sediment from river flows which carry carbon from all the ecosystems upstream. The carbon-laden sediment then stays in storage for hundreds of years. This means, unlike terrestrial forests, mangrove forests can continue to store carbon even after the forest itself is mature and respirates in equilibrium.
Coastal ecosystems are important for climate action for another reason. Existing coastal ecosystems have been storing carbon in this way for a long time. They hold more carbon in sediment and soils, than forests. Therefore, if these ecosystems are lost through land use conversion, all of that carbon will re-enter the atmosphere.
Per acre, coastal ecosystem degradation has a bigger climate impact than deforestation. Its protection is critical to limit global warming. Today, degraded coastal ecosystems release 1.02 billion tonnes of CO2 annually. Protection can reverse this to storage. Yet, coastal ecosystems continue to be lost.
Why is there no data for non-mangrove ecosystems?
You may have noticed that all of the statistics so far, are for mangroves. There is some data for other coastal ecosystems such as salt marshes and seagrass. However, they are not as well studied (yet) as mangroves. Even though there is potential for carbon storage, estimating how much storage happens still requires some work. Even for mangroves, estimating the storage of carbon that comes from outside the ecosystem is still a subject of study.
Are there blue carbon offsetting projects?
So, does that mean that there are no blue carbon offsetting projects yet? Last year, I would have answered a clear no. However (and just to show how quickly climate action develops), just this year Verra submitted a methodology to the UNFCCC to qualify and audit blue carbon projects.
At the moment, methodologies that exist only cover restoration of degraded mangroves, and small scale reforestation/afforestation of wetlands. These methodologies are very conservative, since they don't consider the second kind of blue carbon storage, i.e. carbon from outside the ecosystem. This is because in issuing carbon credits, the certainty for what the credit means is more important. Remember that carbon offsetting is really an effort to fix the economic system, so that it stops damaging the natural one. It's about putting climate action into an accounting framework, so that we can better manage it.
When the science is more certain, they would probably be updated to account for it. It could be soon; the Blue Carbon Initiative have issued a manual that provides guidance for how to consider this for mangroves, salt marshes, and seagrass.
Clean Development Mechanism (CDM) methodologies for blue carbon
Due to the developing state of knowledge, most blue ecosystem projects are not yet ready to become carbon offsetting projects. This is not because restoration of coastal habitats do not store carbon. It's because a carbon offsetting project gets to earn carbon credits. So you have to be able to calculate how much carbon was removed - and stayed removed - by the ecosystem. And that's the part that's missing or incomplete for now.
At this time, it is possible to have a genuine accredited mangrove or wetland project. However, the storage estimates per credit sold would definitely be less than the real storage, because prevailing methodologies simply don't count the major way that these ecosystems can store carbon.
At the moment, they are basically the same as would apply to a reforestation or afforestation carbon offsetting project. The additional considerations are on what kind of land would or wouldn't qualify. Largely this is related to hydrology changes due to the project. For example, large scale restoration of degraded mangroves must not include more than 10% of non-mangrove species, unless it will not impair coastal hydrology.
The downside of this situation is that your blue carbon offset is probably worth more than the project can tell you. The upside is that if you did your carbon offset via a blue carbon project, you're really net positive rather than just neutral. You just don't know by how much, that's all.
What are potential future blue carbon projects?
At the moment, the blue carbon ecosystems that we focus on are semi-land, semi-marine. This is mainly because these ecosystems are sort of similar to forests and grassland. So we are halfway there in terms of understanding how to account for their carbon storage.
However, blue carbon potential is greater than that. There are fully marine ecosystems that may also be significant carbon storage, or could be. After all, more than 80% of the global carbon cycle passes through the oceans. Here are some of the possible candidates for future blue carbon projects.
Seagrass occupies less than 0.2% of the ocean, yet they store 10% of carbon buried in the ocean every year. Its restoration is also attractive from a Biodiversity Crisis perspective, providing habitat and feeding grounds for various marine species.
Algae cultivation & kelp forests
Algae such as seaweed and kelp are another kind of photosynthesising life form. Therefore, they will also absorb carbon through natural processes. Kelp can grow into underwater forests that constitute a kind of ecosystem, providing habitat and shore protection benefits. On the other hand, seaweed cultivation can scale up as an agricultural activity.
The role of blue carbon in Small Island Developing States (SIDS)
There is an extra reason that blue carbon is important in climate action.
Most carbon offsetting projects and green financing relate to activities more commonly carried out in larger or continental states. Most renewable energy projects, even if offshore, are only viable if they supply a large land demand. Agricultural projects and reforestation are all related to continental countries. Even REDD+ funding would only go to developing countries that have significant forests.
But there is a category of states that are missing out. Small Island Developing States (SIDS) are nations across our oceans, with no significant land mass, but a lot of sea. They are the most exposed to climate change. Some of them would cease to exist with sea level rise, forcing them to contemplate becoming climate refugees. Most are not developed states, and therefore - like other developing countries - have a low technology base with which to mitigate and adapt.
But, if coastal and marine ecosystems can in fact slow down climate change, carbon credit funding could be an additional flow of finance to help SIDS respond. It would also be funding that does not have 'aid' connotations, which probably means a great deal. As someone who is also from the developing world, I would guess so.
The worldview of SIDS nations & sea level rise
On the other hand, SIDS are not just victims of sea level rise. After all, their very cultures are oceanic. With the assistance of funding and technology, SIDS may actually pioneer the most effective and disruptive climate adaptation solutions. For example, French Polynesia had been pioneering the first experiments in modern seasteading, which would easily be compatible with marine ecosystem cultivation. This would go a long way towards increasing the survival of oceanic nations.
Issues of environmental justice are unique for SIDS even relative to the rest of the developing world, as you can see. On the one hand, they are the most at risk and have the least capability to do something about it, yet probably contributed the least to the problem. But on the other hand, if technology allows them to go fully oceanic, it would be the start of a new era of humankind.
In that era, land-based cultures can learn a lot from the worldview of SIDS. They can teach us how to truly live on a blue planet.
- Verra's first blue carbon methodology & potential REDD+ update for coastal forests.
- Follow Blue Carbon Lab & The Blue Carbon Initiative.
An important part of the Paris Agreement is recognition that countries must have the freedom to choose the combination of methods for how they meet their climate ambitions, because each nation has vastly differing circumstances. A solution that doesn't make sense to one country - however large and influential - may be perfect for another. Can blue carbon solutions be how your country meets its climate commitments?