While governments around the world are not doing nearly enough to halt climate change, there has been an almost disproportionate emphasis in popular media on quick fixes. These pipe dreams are popular because they don’t talk about the need to drastically cut planet-heating carbon emissions. Rather they are all about finding ways to take out the emissions from the atmosphere. These are mostly plans of capturing carbon from the atmosphere and burying it in the ground—and it’s a pipe dream because it assumes that we are just going to continue using fossil fuels just as we are right now.
Many of these carbon capture and storage fantasies are centered around technologies that either don’t yet exist, or are difficult to scale up to an extent that makes them feasible. However, there’s one “natural fix” that is also very seductive. It’s the idea that you can plant trees in record numbers, and they will suck out the CO2 in the atmosphere. This is scientifically true, of course, but the ability of reforestation to make a difference in stopping climate change is wildly overstated.
In 2020, the World Economic Forum (WEF) made headlines by announcing an initiative to grow, conserve and restore one trillion trees around the world. It stated that the initiative could “provide up to one-third of the emissions reductions required by 2030 to meet the Paris Agreement (2015) targets”. A nature-based solution makes sense right? But here’s the thing: While growing, conserving and restoring the natural habitat is a vital necessity, planting trees isn’t enough to stop climate change. Scientists have argued that even a trillion trees would take centuries to lock in atmospheric CO2.
There is also the reality that haphazard afforestation, without taking into consideration local conditions, could actually make the problem worse. And usually, afforestation programmes end up planting monoculture forests, instead of mixed-species natural forests.
New research was published this past week which looks at the problems of afforestation when it comes to sensitive marine habitats. These are called blue carbon habitats, and they are under threat all over the world, including in India, from development projects like new ports and industrial plants. In the review article Carbon Removal Using Coastal Blue Carbon Ecosystems Is Uncertain And Unreliable, With Questionable Climatic Cost-Effectiveness, published in the journal Frontiers in Climate, researchers argue that while it is of paramount importance that we conserve coastal habitats, the active restoration of such habitats to remove CO2 from the atmosphere is challenging and risky.
The researchers state that the problem arises from the fact that countries and businesses are increasingly focusing on using marine habitat restoration to offset their carbon emissions, while assuming that the relationship is a simple transactional one. “If we use these ecosystems for carbon offsets in a major way, expecting that they would remove up to, say, 100 gigatonnes of carbon dioxide over the period 2025-2100, but find they only remove 10 or maybe just one gigatonne of CO2, then climate tipping points could be crossed, with really serious consequences,” says Dr. Phillip Williamson from the School of Environmental Sciences, University of East Anglia, and the lead author of the article.
Just as with planting trees, it is questionable to look at marine habitat restoration as a substitute for ditching fossil fuels. Instead, as Dr. Williamson says, coastal ecosystems should be conserved and restored to protect biodiversity. Doing so would protect local livelihoods and also help protect coastlines. If they also end up removing some CO2 from the atmosphere, that would be a bonus. “Restoration should therefore be in addition to, not as a substitute for, near-total emissions reductions.”