Climate change is one of the most pressing and pervasive challenges facing humanity in the 21st century. The accumulation of greenhouse gases (GHGs) in the Earth’s atmosphere, particularly carbon dioxide (CO₂), has been a primary driver of global warming, which has led to rising sea levels, extreme weather events, and shifts in ecosystems [1]. The current pace of CO₂ emissions, primarily from fossil fuel combustion, deforestation, and industrial activities, far exceeds the planet’s natural ability to absorb or mitigate the impact. As a result, global temperatures are rising, with far-reaching consequences for biodiversity, food security, public health, and overall planetary stability, international efforts have largely focused on reducing GHG emissions by transitioning to renewable energy sources, improving energy efficiency, and adopting sustainable practices in agriculture, transportation, and industry. While reducing emissions is crucial, there is growing recognition that these efforts alone will not be sufficient to limit global warming to safe levels [2]. Even with rapid reductions in emissions, the CO₂ that has already been released into the atmosphere remains a major threat, potentially pushing the climate past tipping points that will cause irreversible damage. Therefore, a multi-faceted approach to climate mitigation is necessary, with carbon sequestration emerging as a vital component of the solution.

Carbon sequestration refers to the process of capturing CO₂ from the atmosphere and storing it in a manner that prevents it from being released back into the air. This can be achieved through both natural and engineered methods. Natural processes include the absorption of CO₂ by forests, soils, and oceans. Terrestrial carbon sequestration, for example, involves the absorption of CO₂ by plants during photosynthesis, which is then stored in the biomass and soil. Oceans act as a significant carbon sink, with marine plants, such as phytoplankton, absorbing CO₂ during photosynthesis [3]. However, natural sequestration alone is insufficient to offset the current rate of CO₂ emissions, especially with deforestation and changes in land use that reduce the Earth’s capacity to absorb carbon. Given this, engineered carbon sequestration technologies have become increasingly important as part of the global strategy to mitigate climate change. These technologies can capture CO₂ directly from industrial sources or even the ambient air, where CO₂ concentrations are relatively low, and store it safely for long periods. The scope and scale of these technologies are still evolving, with several promising approaches currently under research and development. The most notable of these include Direct Air Capture (DAC), Bioenergy with Carbon Capture and Storage (BECCS), soil carbon sequestration, ocean fertilization, and carbon mineralization.

Direct Air Capture (DAC) involves using chemical processes to capture CO₂ from ambient air, which is then either stored in geological formations or used in the production of various materials. This technology has been hailed as one of the most promising solutions for mitigating climate change because of its potential to remove CO₂ from the atmosphere directly. Similarly, BECCS combines bioenergy production with carbon sequestration, capturing the CO₂ released from biomass combustion and storing it underground. This technology offers the dual benefit of generating energy while simultaneously removing CO₂ from the atmosphere [4].

Soil carbon sequestration, on the other hand, involves increasing the amount of carbon stored in the soil through improved land management practices, such as no-till farming, agroforestry, and crop rotation. These practices can enhance soil fertility while sequestering significant amounts of CO₂. Other methods, such as ocean fertilization, aim to stimulate the growth of marine organisms that absorb CO₂ through photosynthesis and store it in the ocean’s depths [5]. Additionally, carbon mineralization processes involve capturing CO₂ and converting it into stable minerals, providing a long-term and safe storage solution. The potential of these technologies to scale up and make a significant impact on climate change mitigation is undeniable. However, the widespread implementation of these methods faces several hurdles, including high costs, technological limitations, environmental risks, and concerns about long-term storage security, many of these technologies require careful consideration of their social, ethical, and economic implications. Despite these challenges, carbon sequestration represents a critical tool in the broader strategy to combat climate change and help the world meet ambitious climate goals, such as those set forth in the Paris Agreement.

Major decarbonization technologies aim to reduce CO₂ emissions by addressing both the supply and demand sides of energy systems. Key conventional mitigation strategies include renewable energy sources, nuclear power, carbon capture, utilization, and storage (CCUS), fuel switching, and improvements in energy efficiency. These technologies are extensively utilized across critical sectors, such as power generation, industry, transportation, and buildings, to significantly lower greenhouse gas emissions. By integrating these approaches, a transition toward a more sustainable and low-carbon future becomes increasingly attainable copyright permission from Springer and reference of [9].

Understanding Carbon Sequestration

Carbon sequestration occurs naturally in forests, oceans, and soils. Terrestrial carbon sequestration, also known as biological sequestration, involves the absorption of CO2 by plants during photosynthesis, which is then stored in vegetation and soil. Oceanic sequestration occurs when CO₂ dissolves in seawater or is absorbed by marine organisms. However, these natural processes are insufficient to offset the vast amounts of CO₂ emitted by human activities [6].To address this issue, artificial or engineered approaches to carbon sequestration have been developed, enabling the capture, storage, and utilization of CO₂ from industrial sources and the atmosphere. These methods can significantly enhance the Earth’s ability to manage excess carbon and mitigate the adverse effects of climate change.

Emerging Technologies in Carbon Sequestration

1. Direct Air Capture (DAC)

Direct air capture (DAC) is one of the most promising technologies for removing CO₂ directly from the atmosphere. DAC involves using chemical processes to captureCO₂ from ambient air, which is then stored underground or converted into useful products. The captured CO₂ can be stored in geological formations or used for enhanced oil recovery, or even transformed into building materials such as carbon-neutral concrete. While DAC technologies are still in the early stages, their potential to scale up in the future is significant.

2. Bioenergy with Carbon Capture and Storage (BECCS)

Bioenergy with carbon capture and storage (BECCS) combines bioenergy production with carbon sequestration. In this process, biomass, such as plant material or agricultural waste, is used to generate energy. The CO₂emitted during combustion is captured and stored underground, making the entire process net-negative in terms of carbon emissions. BECCS has been proposed as a key solution for achieving negative emissions, although it faces challenges related to land use, biomass supply, and storage capacity [7].

3. Soil Carbon Sequestration

Soil carbon sequestration involves increasing the amount of carbon stored in the soil through agricultural practices such as no-till farming, cover cropping, agroforestry, and improved pasture management. Healthy soils are capable of storing significant amounts of carbon, thus acting as a natural sink for atmospheric CO₂. This approach not only mitigates climate change but also improves soil fertility, enhances biodiversity, and supports sustainable agriculture.

4. Ocean Fertilization and Algal Carbon Sequestration

Ocean fertilization is an approach that involves introducing nutrients, such as iron, into ocean waters to stimulate the growth of phytoplankton. Phytoplankton absorb CO₂during photosynthesis and, when they die, the carbon is transported to the ocean floor, where it can be stored for long periods. Although ocean fertilization has shown promise, its effectiveness, potential ecological risks, and ethical concerns remain topics of ongoing research and debate.

5. Carbon Mineralization

Carbon mineralization, also known as enhanced weathering, involves the process of converting CO₂ into stable minerals by reacting it with naturally occurring minerals such as basalt. This process occurs naturally over geological timescales, but researchers are working to accelerate the process to make it more efficient. By injecting CO₂ into rock formations, it can be chemically bound into minerals, providing a long-term and safe storage solution [8].

Global Impacts and Challenges

While carbon sequestration technologies have the potential to play a significant role in climate change mitigation, several challenges must be addressed to make these approaches scalable and effective.

1. Cost and Economic Viability

Many of the emerging carbon sequestration technologies, such as DAC and BECCS, are still costly and not yet economically viable at large scales. The high costs associated with capturing, storing, and transporting CO₂ are significant barriers to their widespread adoption. Governments and private industries will need to invest in research, development, and infrastructure to bring down costs and improve efficiency.

2. Storage Capacity and Safety

The storage of captured CO₂, especially in geological formations, raises concerns about the long-term safety and monitoring of storage sites. If CO₂ were to leak from storage sites, it could undermine the effectiveness of carbon sequestration efforts and contribute to further environmental harm. Ensuring the integrity of storage sites and monitoring for potential leaks will be critical to the success of these technologies.

3. Environmental and Social Impacts

Some carbon sequestration methods, such as ocean fertilization and BECCS, may have unintended environmental consequences, such as disrupting marine ecosystems or competing with food production for land. Additionally, large-scale deployment of these technologies could lead to social and ethical concerns, such as land ownership, food security, and the impact on local communities. A balanced approach that considers the environmental, social, and ethical implications is necessary for the sustainable implementation of carbon sequestration.

4. Policy and Global Cooperation

For carbon sequestration technologies to be effective, they must be integrated into national and international climate policies [8]. Global cooperation and clear regulatory frameworks will be essential for guiding the deployment of these technologies and ensuring that they are implemented in a way that maximizes their benefits and minimizes risks. Carbon pricing, government incentives, and international climate agreements will play a key role in driving the adoption of carbon sequestration.

Conclusion

Innovative approaches to carbon sequestration offer promising solutions for mitigating climate change by reducing the concentration of CO₂ in the atmosphere. Emerging technologies such as DAC, BECCS, soil carbon sequestration, ocean fertilization, and carbon mineralization have the potential to complement efforts to reduce greenhouse gas emissions and help achieve global climate targets. However, these technologies face significant economic, environmental, and social challenges that need to be addressed through continued research, investment, and international cooperation.Ultimately, carbon sequestration can serve as a critical tool in the global effort to combat climate change, but it must be viewed as part of a broader strategy that includes reducing emissions, promoting sustainable practices, and transitioning to renewable energy sources. The future of carbon sequestration depends on the collective efforts of governments, industries, scientists, and communities working together to build a sustainable, low-carbon future.

References

1. Metting, F. B., Smith, J. L., Amthor, J. S., &Izaurralde, R. C. (2001). Science needs and new technology for increasing soil carbon sequestration. Climatic change, 51(1), 11-34.
2. Adenle, A. A., Azadi, H., &Arbiol, J. (2015). Global assessment of technological innovation for climate change adaptation and mitigation in developing world. Journal of environmental management, 161, 261-275.
3. Adenle, A. A., Azadi, H., &Arbiol, J. (2015). Global assessment of technological innovation for climate change adaptation and mitigation in developing world. Journal of environmental management, 161, 261-275.
4. Fawzy, S., Osman, A. I., Doran, J., & Rooney, D. W. (2020). Strategies for mitigation of climate change: a review. Environmental Chemistry Letters, 18, 2069-2094.
5. Wennersten, R., Sun, Q., & Li, H. (2015). The future potential for Carbon Capture and Storage in climate change mitigation–an overview from perspectives of technology, economy and risk. Journal of cleaner production, 103, 724-736.
6. Bhattacharyya, S. S., Leite, F. F. G. D., Adeyemi, M. A., Sarker, A. J., Cambareri, G. S., Faverin, C., … & Parra-Saldívar, R. (2021). A paradigm shift to CO2 sequestration to manage global warming–With the emphasis on developing countries. Science of the Total Environment, 790, 148169.
7. Nazir, M. J., Li, G., Nazir, M. M., Zulfiqar, F., Siddique, K. H., Iqbal, B., & Du, D. (2024). Harnessing soil carbon sequestration to address climate change challenges in agriculture. Soil and Tillage Research, 237, 105959.
8. Lobus, N. V., Knyazeva, M. A., Popova, A. F., &Kulikovskiy, M. S. (2023). Carbon Footprint Reduction and Climate Change Mitigation: A Review of the Approaches, Technologies, and Implementation Challenges. C, 9(4), 120.
9. Fawzy, S., Osman, A.I., Doran, J. et al. Strategies for mitigation of climate change: a review. Environ Chem Lett 18, 2069–2094 (2020). https://doi.org/10.1007/s10311-020-01059-w