Carbon Reduction: Saving Our Oceans

The ocean is the world's greatest ally in the fight against climate change. Covering over 70% of the Earth's surface, it absorbs 90% of the heat and 25-30% of the carbon dioxide emissions caused by human activity. However, the increasing temperature and acidity of the ocean due to carbon pollution are making the seas uninhabitable for many organisms, disrupting ocean currents, and altering food webs. To protect the ocean and its biodiversity, it is crucial to reduce carbon emissions and implement ocean-based carbon removal approaches, such as conserving coastal ecosystems and investing in offshore energy production. By slowing down warming, acidification, and deoxygenation, we can give marine species and ecosystems more time to adjust and avoid widespread collapse.

Reducing carbon pollution slows ocean warming

The ocean is central to stabilising the Earth's climate and reducing global greenhouse gas emissions. It is the world's greatest ally against climate change, absorbing 90% of the excess heat caused by carbon pollution and other greenhouse gases emitted by humans.

The ocean has absorbed about 90% of the warming that has occurred in recent decades due to increasing greenhouse gases, and 30% of the carbon dioxide released into the atmosphere. However, this has come at a cost to the ocean's health. As the ocean continues to absorb more heat and carbon dioxide, it becomes warmer and more acidic, disrupting ocean currents and altering food webs that humans, plants, and animals rely on.

By reducing carbon pollution, we can slow down ocean warming and give marine species and ecosystems more time to adjust to the changing conditions. This will help to avoid the widespread extinction of marine species and the collapse of marine ecosystems.

Reducing carbon pollution will also help to protect coastal communities. Slower sea level rise will allow coastal systems, such as wetlands and mangroves, to better protect these communities and give them more time to prepare for the impacts of climate change.

The ocean's ability to function as a carbon sink depends on its rich biodiversity. Mangrove forests, seagrass beds, and coral reefs are all crucial carbon sinks and provide numerous benefits that support life on Earth. Mangroves, for example, store on average 1,000 tonnes of carbon per hectare, while also supporting healthy fisheries, improving water quality, and providing coastal protection.

By reducing carbon pollution, we can help protect and restore these vital ecosystems, ensuring the ocean can continue to play its critical role in mitigating the impacts of climate change.

Less ocean warming means less ocean acidification

Ocean acidification is the process by which seawater becomes more acidic due to the excess carbon dioxide it absorbs from the atmosphere. This occurs as carbon dioxide dissolves into the ocean, triggering a chemical reaction that increases acidity over time. The more carbon dioxide that is released into the atmosphere through human activity, such as burning fossil fuels, the more the ocean absorbs, and the more acidic it becomes.

The average acidity of seawater has increased by 30% since the Industrial Revolution, and the pH of ocean water is expected to continue to fall. This change in ocean chemistry has significant ramifications for ocean ecologies, food security, and economies that depend on marine industries. For example, the shellfish industry could lose more than $400 million annually by 2100 if ocean acidification is left unchecked.

By reducing carbon pollution, we can slow the rate of ocean acidification, giving marine species and ecosystems more time to adjust to changing conditions. This will help to protect the biodiversity and economic value of our oceans, as well as the billions of people worldwide who rely on the ocean as their primary source of food and income.

Less ocean acidification helps marine life

The increased acidity of the ocean has a twofold impact on marine life: it reduces the availability of carbonate ions, which are essential for building shells and skeletons, and it increases the acidity of the seawater itself. The former affects the ability of marine organisms to build and maintain their protective shells and skeletons, while the latter can impair the overall health of marine life.

For example, in more acidic conditions, mussels and oysters are expected to grow less shell by 25% and 10% respectively by the end of the century. Additionally, the increased acidity can affect the development of larvae, impacting their ability to survive and reach adulthood. This, in turn, can have repercussions on the food sources for other marine organisms and humans, threatening food security for millions.

By reducing carbon pollution, we can help to slow down ocean acidification, giving marine species more time to adjust to changing conditions and preserving the health and biodiversity of our oceans.

Protecting coastal ecosystems helps the ocean

Protecting coastal ecosystems is crucial for safeguarding the ocean and mitigating the impacts of climate change. These ecosystems provide essential services that contribute to the health and resilience of the ocean. Here are some reasons why protecting coastal ecosystems is vital:

• Carbon sequestration: Coastal habitats such as mangroves and seagrasses are highly effective at sequestering carbon dioxide from the atmosphere. Mangroves, in particular, are carbon-rich ecosystems, storing large amounts of carbon in their biomass and soils. Protecting and restoring these habitats helps combat climate change by reducing the amount of carbon dioxide in the atmosphere.
• Storm protection: Wetlands, sand dunes, reefs, and other coastal ecosystems act as natural buffers against storms. They slow down waves, reduce their height and intensity, and prevent erosion. This results in decreased storm surges, more stable shorelines, and enhanced resilience for coastal communities. Protecting these ecosystems is a nature-based solution that helps safeguard both the environment and vulnerable communities.
• Biodiversity support: Coastal ecosystems, such as coral reefs, provide a habitat for a diverse range of marine life. Coral reefs cover less than 0.1% of the ocean's surface but support over 25% of marine biodiversity. Protecting these ecosystems ensures the preservation of numerous species and maintains the delicate balance of ocean life.
• Economic benefits: Coastal ecosystems contribute significantly to local economies. They support industries such as fisheries and tourism, providing income and livelihoods for coastal communities. Additionally, healthy coastal ecosystems reduce the costs associated with climate change impacts, such as flooding and storm damage. Protecting these ecosystems helps maintain economic stability and prosperity for coastal regions.
• Water quality improvement: Coastal habitats, including mangroves and wetlands, play a crucial role in improving water quality. They act as natural filters, trapping sediments and pollutants before they reach the ocean. This helps maintain the health of marine ecosystems and ensures clean water for marine life and human communities alike.
• Climate change adaptation: Protecting coastal ecosystems is a vital component of adapting to and mitigating the effects of climate change. As the planet warms, coastal communities become increasingly vulnerable to flooding and sea-level rise. Coastal ecosystems act as a natural defence, providing protection and resilience. Preserving these ecosystems is essential for helping communities adapt to the changing climate and reducing their vulnerability to climate-related disasters.

Reducing emissions protects human communities

The ocean is central to stabilising the Earth's climate and reducing global greenhouse gas emissions. As the world's largest carbon sink, the ocean absorbs 25-30% of all carbon dioxide emissions and 90% of the excess heat generated by these emissions.

However, the increasing greenhouse gas emissions have negatively impacted the ocean's health, warming and acidifying seawater, and causing detrimental changes to life underwater and on land. This, in turn, affects human communities, as the ocean plays a crucial role in providing for and protecting them.

Protecting Human Communities

The ocean is essential for human communities, offering protection, food sources, and economic opportunities. Firstly, the ocean is a vital buffer against the impacts of climate change, absorbing heat and energy from rising greenhouse gas emissions. This helps to reduce the severity of climate change-induced events, such as floods and storms, which disproportionately affect highly vulnerable communities in low-lying areas and small islands. By slowing down warming and sea-level rise, reducing emissions can give human communities more time to prepare and adapt to changing conditions.

Secondly, the ocean provides food and economic opportunities for millions of people worldwide. Fisheries and aquaculture industries are vital sources of livelihood and nutrition for coastal communities, including Indigenous peoples. However, warming oceans and ocean acidification are disrupting these industries. For example, warming waters are causing fish stocks to migrate poleward, forcing fishermen to travel farther to catch the same species. Additionally, ocean acidification makes it more difficult for organisms like oysters and shellfish to build shells, impacting the shellfish industry.

Furthermore, the ocean's ability to absorb carbon and mitigate climate change is closely tied to its health and biodiversity. Coastal ecosystems such as mangroves, seagrasses, and coral reefs are essential carbon sinks, sequestering carbon dioxide from the atmosphere at much higher rates than terrestrial forests. These ecosystems also support healthy fisheries, improve water quality, and provide coastal protection. However, human activities such as overfishing, pollution, and climate change are severely compromising their health. Protecting and restoring these ecosystems is crucial for maintaining the ocean's ability to absorb carbon and safeguard human communities from the worst impacts of climate change.

The Way Forward

To protect human communities from the impacts of climate change, it is essential to reduce carbon emissions and mitigate ocean warming and acidification. This involves a combination of approaches, including investing in offshore energy production, conserving and restoring coastal ecosystems, and removing carbon dioxide from the atmosphere. Transitioning to zero-emission energy sources in the shipping industry, for example, can help reduce greenhouse gas emissions and protect the ocean's health. Additionally, restoring coastal blue carbon ecosystems, such as mangroves and seagrasses, can increase carbon sequestration and provide co-benefits like reducing coastal erosion and improving water quality.

Addressing the climate crisis requires a multifaceted approach that includes both emissions reduction and carbon removal. By leveraging the ocean's potential as a carbon sink and implementing sustainable practices, we can protect human communities and work towards a more resilient future.

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