Recall by how much the acid levels in the ocean have increased by over the past 250 years.

Over the past 250 years, the acid levels in the ocean have increased significantly due to the absorption of atmospheric carbon dioxide (CO₂) generated by human activities, primarily fossil fuel combustion and deforestation. This phenomenon, known as ocean acidification, has led to a decrease in pH levels in seawater.

Specifically, since the beginning of the Industrial Revolution, ocean acidity (measured by pH) has decreased by approximately 0.1 units, which corresponds to a 30% increase in acidity. This shift from a pH of about 8.2 to approximately 8.1 represents a significant change in ocean chemistry, affecting marine ecosystems, particularly organisms that rely on calcium carbonate, such as corals and shellfish.

The ongoing rise in CO₂ emissions continues to pose a threat to marine life and overall ocean health, making it crucial to address climate change and reduce greenhouse gas emissions to mitigate further acidification effects.