Report Warns: Oceans on the Brink of Becoming Too Acidic to Support Marine Life

The world’s oceans are nearing a critical point of acidification that could make them unable to sustain marine life or regulate the climate effectively, according to a new report released on Monday.

The report, published by the Potsdam Institute for Climate Impact Research (PIK), highlights nine key factors essential for maintaining Earth’s life-supporting systems. Of these, six have already surpassed safe thresholds due to human activities, and ocean acidification is on the verge of becoming the seventh.

The breached boundaries include factors like climate change, biodiversity loss, habitat destruction, freshwater depletion, and the increase in pollutants such as plastics and chemical fertilizers used in agriculture. Now, with rising carbon dioxide (CO2) emissions from the burning of fossil fuels like coal, oil, and gas, the oceans are absorbing more CO2, pushing them closer to unsustainable acidification levels.

“As CO2 emissions rise, more of it dissolves in seawater, leading to increased acidity in the oceans,” explained Boris Sakschewski, a lead author of the report. He added that even with rapid cuts to emissions, some level of acidification will persist due to the CO2 already released and the time it takes for ocean systems to recover. Consequently, crossing the ocean acidification threshold appears inevitable in the near future.

The increasing acidity poses a significant threat to marine ecosystems, as it harms corals, shellfish, and phytoplankton—key components of the food chain. This disruption could impact the food security of billions of people and limit the ocean’s ability to absorb CO2, which helps mitigate global warming.

Among the nine planetary boundaries identified by PIK, the only one not immediately at risk of being crossed is the protective ozone layer. Damaged by man-made chemicals, it has been recovering since 1987 when many of these chemicals were banned. However, the threshold related to fine particulate matter in the atmosphere—tiny particles that can cause respiratory diseases—is nearing dangerous levels, though efforts to improve air quality in several countries have shown some signs of progress.

The nine planetary danger zones outlined by PIK serve as warnings about tipping points that could push Earth’s natural systems beyond recovery. If crossed, these thresholds could result in irreversible and catastrophic consequences for billions of people and future generations.

Sakschewski emphasized the interconnected nature of these boundaries, explaining that exceeding one could destabilize the entire planet’s life-support systems. However, addressing one issue—such as preventing global temperatures from rising more than 1.5°C above pre-industrial levels—could yield positive effects across multiple environmental challenges.