The answer is "Increased carbon Dioxide levels have made the oceans more alkaline.
Explanation:
Google states "In the natural environment carbonate alkalinity tends to make up most of the total alkalinity due to the common occurrence and dissolution of carbonate rocks and presence of carbon dioxide in the atmosphere."
The current increase of carbon dioxide in the atmosphere is as a result of human activities that began in the late 1700s. This period sparked the beginning of the Industrial Revolution and this is when we began to use fossil fuels. The burning of fossil fuels coupled with widespread global deforestation has led to a rise in CO2. Excess carbon dioxide in the oceans causes it to become more acidic. This acidity will affect marine species with shells like mussels and lobsters. <span />
