Final answer:
Ocean acidification has various negative consequences, but it does not lead to an increase in lobsters and crabs.
Step-by-step explanation:
Ocean acidification is the process of ocean waters decreasing in pH due to the absorption of carbon dioxide from the atmosphere. This change in pH has several negative consequences, including decreased fisheries and tourism, a potential shortage of food supply, and hindrance to the economy due to acidification of fish caught in cooler waters. However, lobsters and crabs will not increase as their shells form differently than calcifying organisms, so they are not directly affected by ocean acidification.