Earth Week Day 6 - Global Goal 14

Global Goal 14: Life Below water

Waste in the ocean is a huge problem. Fish can eat microplastics, animals can get caught in nets or other packaging made from single use plastics. A good documentation to watch is „A Plastic Ocean“.

Many endangered species are directly affected by human activity. Sea turtles often eat plastic bags they mistake for jellyfish. Whales and sharks are often hunted. Sharks are hunted out of fear or finned and left to sink to the bottom of the ocean and drown for the sake of making a dish. Whales are considered a delicacy in many areas and the consumption has caused their numbers to decline rapidly.

Ocean acidification is the decrease in the pH of the Earth’s ocean. Between 1950 and 2020, the average pH of the ocean surface fell from approximately 8.15 to 8.05. You calculate the PH level with the logarithm of the concentration of hydronium ions.

Carbon dioxide emissions from human activities are the primary cause of ocean acidification, with atmospheric carbon dioxide (CO2) levels exceeding 410 ppm (in 2020). CO2 from the atmosphere is absorbed by the oceans. This produces carbonic acid which dissociates into a bicarbonate ion and a hydrogen ion. The presence of free hydrogen ions lowers the pH of the ocean, increasing acidity (this does not mean that seawater is acidic yet; it is still alkaline, with a pH higher than 8).

If this trend continues we will end up with acidic seawater, which kills coral reefs and other oceanic plants. It makes the habitat more and more hostile.