Development of blue carbon ecosystems: An effective climate engineering approach for managing drastic climate impact on coastal regions

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Under the Climate Engineering Governance Initiative created in 2018 (which currently serves as an international platform for collaboration and coordination on climate resilience strategies), climate engineering consists of experimental strategies aiming not only at shielding the Earth from the warming induced by greenhouse gas (GHG) emissions, but also off-setting accumulated GHG from the atmosphere.


Climate engineering approaches include a diverse array of climate mitigation and adaptation methodologies (ecosystem restoration, blue carbon engineering, space-based geoengineering, stratospheric aerosol injection, albedo modification, marine cloud brightening, ocean albedo modification, direct air capture, carbon capture and storage) of which blue carbon ecosystems appear as an innovative way for mitigating drastic climate change impact on coastal regions as reaffirmed at the COP 26 held in 2021 in Glasgow (Scotland, United Kingdom).


Blue carbon engineering constitutes a potential way to mitigate and reverse the effects of global warming and drastic climate change impact on coastal regions. This engineering process consists of developing natural coastal, estuarine and marine photosynthetic ecosystems (saltmarshes, seagrass meadows, mangrove forests, macroalgae communities such as kelp forests, and freshwater tidal ecosystems such as coastal bald cypress floodplain forests) that have the capability to absorb significant amounts of carbon dioxide from the atmosphere and the environment through a long-term bio-sequestration process. 


The potential and effectiveness of blue carbon engineering in carbon sequestration and climate change mitigation process lie in the extremely high productivity of these ecosystems with huge carbon storage capability over thousands of years. Through the development of blue carbon engineering at diverse coastal regions worldwide, seagrass meadows, mangrove forests and salt marshes, which cover approximately 0.5% of the coastal regions, account for more than 50% of all blue carbon and carbon sequestration in ocean sediments.


Concretely, recent global experimental researches on blue carbon engineering showed that seagrass meadows, mangrove forests, and salt marshes (that build coastal soils at a median rate of 5.5, 4.5 and 1.48 millimetres per year, respectively) could not only potentially achieve a long-term sequestration ranging from 65 to 85 % of the total carbon emissions from the coastal regions and nearby environment, but also significantly mitigate drastic climate impacts on these regions. In this regard, the development and promotion of blue carbon engineering in the Greater Pearl River Delta Region might be an effective way for enhancing the regional climate resilience strategies.


This article is contributed by Ir Dr Alex Gbaguidi with the coordination of the Environmental Division.

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