Oceans are getting acidic. Marine life faces existential crisis

One of the most pressing concerns highlighted in the report is ocean acidification, which is primarily driven by rising atmospheric CO2 levels due to fossil fuel emissions.

In Short

• The ramifications of this transgression are profound
• The report emphasises that ocean acidification is not uniform
• Regions like the polar areas are already experiencing heightened effects

A new report has revealed alarming insights into the health of our planet, indicating that Earth is far beyond its safe operating limits.

The inaugural Planetary Health Check, produced by the Planetary Boundaries Science (PBScience) initiative, points to the precarious state of six out of nine key planetary boundaries, with ocean acidification perilously close to being breached.

The report, led by Earth System scientist Johan Rockstr¶m and the Potsdam Institute for Climate Impact Research, highlights that climate change, biosphere integrity, and other critical boundaries have already been transgressed, leading to a dire prognosis for the planet’s habitability.

“Our updated diagnosis shows that vital organs of the Earth system are weakening,” warns Levke Caesar, a co-author of the report. “We are moving deeper into risk zones that threaten life support functions, increasing the likelihood of crossing irreversible tipping points.”

OCEAN ACIDIFICATION WORSE

One of the most pressing concerns highlighted in the report is ocean acidification, which is primarily driven by rising atmospheric CO2 levels due to fossil fuel emissions.

Currently, the global aragonite saturation — a measure of ocean acidity — stands at 2.80, just above the critical threshold of 2.75. If current trends continue, scientists predict that ocean acidification could exceed safe limits within the next few years.

The ramifications of this transgression are profound, threatening the very foundations of marine ecosystems.

DIRE CONSEQUENCES

As acidification progresses, fragile coral reefs and vital phytoplankton populations—crucial for marine food webs—face devastating impacts.

This could lead to the degradation and collapse of global fisheries, exacerbating food insecurity in vulnerable communities and inflicting severe economic damage worldwide. “We are risking losing the planet as we know it,” Caesar warns. “The risk increases the further we push into the red zones.”

The report emphasises that ocean acidification is not uniform; regions like the polar areas are already experiencing heightened effects due to cooler waters absorbing CO2 more rapidly.

Helen Findlay, a biological oceanographer, notes, “I think it puts at risk fully understating the impacts because the polar regions have potentially more weight in terms of their contribution to climate cycles.”

Alongside acidification, other stressors like extreme heat and deoxygenation compound the challenges facing marine life.

Experts are advocating for a comprehensive approach to address these interconnected issues, calling for significant reductions in climate emissions—50% by 2030—to reverse the trend of planetary boundary transgressions.