PHL WATERS KEY TO CLIMATE FIGHT: Biological carbon pump valued at PHP 56 trillion per year

By Francis Allan L. Angelo

A groundbreaking global study published in Nature Climate Change has placed a trillion-dollar value on the ocean’s role in removing carbon from the atmosphere, spotlighting tropical marine regions like the Philippines as critical players in climate mitigation.

The study, released March 27, estimates that the ocean’s biological carbon pump (BCP) sequesters approximately 2.81 billion metric tons (Gt) of carbon annually—roughly 10 billion tons of carbon dioxide (CO₂)—locking it away for at least 50 years.

This natural process provides an economic service valued at more than $1 trillion (PHP 56 trillion) per year, a figure that could reshape how nations view marine conservation in the era of climate change.

Without the BCP, atmospheric CO₂ levels would be 200 parts per million (ppm) higher, the researchers said. For comparison, global fossil fuel emissions were estimated at 36.6 billion tons of CO₂ in 2023, according to the Global Carbon Budget.

The study also highlighted the importance of protecting marine resources from collapsing under human activities.

New Lens on PHL Ocean Stewardship

The study’s release comes as the Philippine government submitted an updated seabed chart of the Philippine Rise to the United Nations, highlighting its potential for oil and gas exploration. But researchers now argue that the same region may hold even greater long-term value as a carbon sink—a crucial natural asset in the fight against climate change.

“The global report highlights the vital role of the ocean’s biological carbon pump in mitigating climate change—an urgent priority for the Philippines as we advance our commitments to climate resilience and marine biodiversity protection,” said Dr. Charina Lyn Amedo-Repollo, physical oceanographer and assistant professor at the University of the Philippines’ Marine Science Institute.

“As a pioneer in establishing marine protected areas in the Coral Triangle, with over 2,000 MPAs, safeguarding key habitats, and integrating the blue economy into our development strategy, the Philippines recognizes that protecting marine ecosystems is both an environmental necessity and an economic opportunity,” she added.

Trillions in Natural Capital

The biological carbon pump works as a vast marine conveyor belt, where phytoplankton, zooplankton, and fishcapture carbon near the ocean surface and transport it to deeper waters through sinking particles and vertical migrations. Once sunk, this carbon can remain trapped for decades or centuries.

The study estimates the BCP’s total value at $2.2 trillion from 2023 to 2030, potentially reaching $7 trillion by 2050, depending on carbon prices and discount rates used for future projections​.

Exclusive Economic Zones (EEZs) like that of the Philippines capture 41 percent of this carbon sequestration, representing roughly 1.16 Gt of carbon annually. However, only 7 percent of this captured carbon occurs within marine protected areas (MPAs).

Globally, 27 percent of BCP carbon is sequestered in Ecologically and Biologically Significant Areas (EBSAs), of which the Philippines hosts three. These EBSAs are often located in regions where industrial activity threatens to undermine their ecological integrity.

PHL Among Top Marine Carbon States

Although countries with large EEZs, such as the United States and Australia, dominate total carbon capture volume, the Philippines is part of a critical tropical corridor where per-area sequestration rates are highest. This makes the nation a key actor in future nature-based climate finance, especially as policymakers seek “bridging solutions” that reduce emissions while delivering co-benefits for biodiversity and local economies.

The Coral Triangle, which includes the Philippines, Indonesia, Malaysia, Papua New Guinea, Solomon Islands, and Timor-Leste, is particularly rich in biodiversity and biological carbon activity.

The study’s authors argue that countries in this region could lead efforts to integrate ocean-based carbon storage into carbon markets, potentially unlocking climate finance mechanisms.

Call for Policy and Market Reform

“The BCP is critical, yet remains unprotected,” said Fabio Berzaghi, lead author of the study and researcher at the World Maritime University. “Without formal inclusion in policy or carbon markets, we risk losing this service.”

Berzaghi and his colleagues propose incorporating the BCP into international agreements, such as the Paris Agreement’s Global Stocktake and the Kunming-Montreal Global Biodiversity Framework, which targets the protection of 30 percent of the world’s oceans by 2030.

They also recommend enabling developing countries to benefit from their oceanic carbon assets through debt-for-nature swaps, carbon credits, and ecosystem service payments, especially for Small Island Developing States (SIDS), which store 11 to 13 percent of global BCP carbon despite their small land area​.

“Accounting of ecosystem services—ecological, climate, and economic benefits—are useful for managing ecosystems and for informing governments,” Berzaghi said. “Damaging nature has a cost for society, and its protection requires funding and holistic approaches.”

Global Sequestration Hotspots

The researchers identified global “carbon sequestration hotspots” where protecting just 10 percent of ocean areas could safeguard 30 percent of the BCP service.

These hotspots include the eastern and northern Pacific, the western coasts of Africa and the Americas, and the Indian Ocean—regions that overlap with many EEZs, including those of the Philippines.

However, many of these areas also face high fishing pressure, deep-sea mining proposals, and pollution, placing them at risk of degradation.

Mary Wisz, co-author of the report and senior scientist at the Technical University of Denmark, emphasized that “Nations can protect the biological carbon pump within their territories with marine protected areas, marine spatial planning, and environmental impact assessments.”

She added that ratifying the Biodiversity Beyond National Jurisdiction (BBNJ) Treaty, agreed upon in 2023, would empower countries to protect carbon sinks in international waters, which store 59 percent of all BCP carbon annually.

From Data to Action

Despite its massive contribution to planetary health, the BCP has been largely ignored in economic planning and global carbon accounting.

According to the study, countries with high debt loads and low credit ratings—including some Southeast Asian nations—could leverage their ocean carbon stocks as natural capital. These valuations could strengthen national climate adaptation strategies while offering new income streams through emerging carbon offset markets.

“There’s a growing push to recognize blue carbon as a real asset in climate finance,” said Berzaghi. “But for that to happen, we need scientific transparency, clear measurement of carbon residence time, and policies that reward conservation.”

For the Philippines, this could mean pivoting its Philippine Rise exploration strategy toward one that balances economic ambitions with climate and ecological stewardship.

“Strengthening protections and aligning ocean-based carbon storage with national and global frameworks will be key to enhancing climate adaptation while fostering sustainable economic growth,” Amedo-Repollo said.