Protecting Blue Carbon From Extreme Weather’s Destruction and For Its Mitigation

The Summer of 2022, with frequent cases of extreme weather conditions around the globe, has finally come to an end as the temperature drops and the floods begin to recede across the world. With extensive reports and analyses covering the significant casualties and economic losses it has caused, extreme weather has proven its power again to everyone. Just like the damages it brought to global markets and societies, extreme conditions can be equally devastating to blue carbon ecosystems. Leaving droughts, storms, floods, and other natural disasters to ruin blue carbon sinks will only worsen climate problems and cause irreversible damage. Blue carbon plays an important role in improving climate challenges so it is essential to make sure the blue carbon sinks—like mangroves, sea grasses, krill, and salt marshes—survive extreme weather cases. Maybe in the near future, a more healthy and mature blue carbon ecosystem can even, in turn, contribute to further improving climatic conditions.

Although blue carbon sink degradation is mostly caused by direct human activities such as industrial pollutants, upstream dams, and dredging, climate change’s impacts still should never be discounted as unimportant. There are many studies discussing the vulnerability of blue carbon to climate change, and it is even considered as a factor that affects the reliability of carbon accounting for blue carbon. Both short-term extreme events (like storms and drought) and long-term climatic changes (such as marine heatwaves and sea levels rising) bring existential threats to the blue carbon ecosystem. Episodic extreme high temperatures—in other words, short but unbearably hot summers—can bring lethal consequences to seagrasses. Mangroves might be more resilient to high temperatures in comparison, but they still cannot survive if heat causes drought. Wind and waves brought by climate change may pose a direct threat to the blue carbon ecosystem by physically damaging or even destroying them. Thus, if we leave extreme weather to wreak havoc, the future outlook for healthy blue carbon sinks will be more and more pessimistic.  

In addition, allowing blue carbon sinks to be destroyed not only damages the ecosystem but also turns a carbon sink into a carbon source. Blue carbon stores carbon by capturing CO2 from the environment and stores the carbon in the plants and soils. According to IPCC, the carbon storage capacity of blue carbon can be up to 1,000 tC ha−1, which is disproportionately higher than most terrestrial ecosystems, and carbon emission is known to contribute to the uptick in global extreme weather. However, blue carbon’s function as a carbon sink will be destroyed once the blue carbon sinks themselves are destroyed. Once destroyed, it will release all the carbon stored in itself from across the years into the atmosphere. The carbon released from blue carbon degradation is comparable to the annual CO2 emission of many small countries. Carbon is a leading contributor to violent global warming and climate change, which also means extra power in creating the next round of global extreme weather. Such a vicious cycle needs to be prevented. 

Although still seen as a very novel idea to many stakeholders and scientists, blue carbon is proving itself to be a very positive player in current climate change mitigation. Aside from its carbon storage capacity, blue carbon sinks can also bring immediate benefits under the current climatic conditions with frequent extreme weather. The global community needs to realize that, although the role of blue carbon sinks in improving climate change is currently difficult to observe or quantify, it has already become an important defense line against extreme weather conditions. For example, nature-based coastlines offer an extra line of protection when severe weather hits. A research conducted by The Nature Conservancy points out that coastal wetlands helped in protecting millions of people from storms, flooding, and other climate-related risks, and can save communities hundreds of millions of dollars by reducing flood damage by up to 29%.

As mentioned previously, blue carbon sinks themselves face enormous challenges from extreme weather when protecting us. Although it is difficult to find effective measures that can immediately and evidently mitigate the negative impacts of extreme climate, researchers and policymakers should actively look for solutions to defend blue carbon sinks against unfavorable conditions; even such approaches might be beyond its financial means in the short term. It is important to first note that the protection of any kind of natural environment should not be determined by merely economic outcomes, and blue carbon and blue carbon sinks are as essential to our planet as any other natural environment.

However, aside from other secondary factors like economical concerns that affect decision-making, the more serious issue that must be recognized is the considerable knowledge gap on how to specifically protect blue carbon sinks. Most scientific research on blue carbon has focused on its carbon stock capability and its role in mitigating climate change. Researchers are aware of the vulnerability of blue carbon in front of extreme weather conditions, but at this stage, there is little research on how to protect blue carbon from destruction in extreme weather conditions. To prevent the natural environment from irreversible damage, human intervention should be executed timely and decisively when the destructive power of the extreme weather far exceeds the self-healing ability of the ecosystem. For example, the Niubeiliang National Nature Reserve of Shaanxi, China, has a developed system that offers different protection schemes to different species in the case of global warming caused by extreme weather conditions. Current research on blue carbon is insufficient to establish a similarly effective mechanism for human intervention programs under extreme weather conditions. Scientists and policy makers need to find out a plan for blue carbon and blue carbon stocks as soon as possible to prepare for the next wave of extreme weather that will inevitably come again.

If we can find a set of effective solutions, policies and protocols related to blue carbon sinks in the cases of extreme weather, the benefits will certainly not let us down. While sometimes difficult to identify in the short-term, their strong carbon storage capacity will definitely make a firm contribution to improving climate change and also to mitigating abnormal extreme weather in the future. Conversely, the consequences of failing to protect blue carbon sinks from both natural and manmade degradation would be something that none of us would like to see.

This commentary was written as part of the BCCC Program Quarterly newsletter’s 2022 Q3 Theme of the Quarter: Global Extreme Weather.