Some coastal regions are becoming much more acidic than previously thought. This rapid acidification is driven by rising atmospheric CO₂ and natural ocean processes, posing a serious threat to marine life and coastal economies., says a recent research from the University of St Andrews shows that Atmospheric CO₂ and ocean pH are closely connected.
As more CO₂ enters the atmosphere, seawater absorbs it, making the ocean more acidic. This process is accelerating in coastal upwelling systems, where deep, acidic waters rise to the surface.
Upwelling Amplifies Acidification
Upwelling brings nutrient-rich, already acidic waters from the deep ocean to the coast. When organic matter sinks and decomposes, it releases CO₂, further increasing acidity. When this water upwells, it reacts with atmospheric CO₂, making coastal waters even more acidic.
Study Methods and Findings
Researchers used historic coral samples and boron isotope signatures to reconstruct acidity changes over the 20th century. They then applied a regional ocean model to predict future changes. The study found that upwelling regions acidify faster than expected from rising atmospheric CO₂ alone.
Implications for Marine Ecosystems
Upwelling systems are among the most productive in the world, supporting major fisheries. Accelerated acidification threatens these ecosystems, with major implications for food security and coastal economies.
Global Examples of Upwelling Regions
The California Current is a key example, but other important upwelling systems include the Humboldt Current off Peru and the Benguela and Canary Currents off West Africa. These regions are now at higher risk due to amplified acidification.
Expert Insights
Dr. Hana Jurikova, Senior Research Fellow, noted that predicting how upwelling systems respond to climate change is complex, as natural and human factors interact to amplify environmental change. Dr. James Rae, Reader in Earth and Environmental Science, emphasized that solutions like heat pumps and electric vehicles also help combat ocean acidification.
Q&A: Understanding Ocean Acidification
Q: Why are coastal areas acidifying faster?
A: Upwelling brings already acidic deep water to the surface, which reacts with atmospheric CO₂, increasing acidity.
Q: What are the impacts of ocean acidification?
A: It threatens marine ecosystems, fisheries, and coastal economies.
Q: Can we slow ocean acidification?
A: Yes, reducing CO₂ emissions through climate solutions can help mitigate acidification.
FAQ: Common Questions About Ocean Acidification
Q: What causes ocean acidification?
A: Increased atmospheric CO₂ is absorbed by seawater, lowering pH and increasing acidity.
Q: Which regions are most affected?
A: Coastal upwelling systems like the California, Humboldt, Benguela, and Canary Currents.
Q: How does acidification affect marine life?
A: It harms calcifying organisms like corals and shellfish, disrupting food webs and fisheries.
