AP Environmental Science 9.7: Ocean Acidification

Determine the pH recorded at Station ALOHA in 2005.
(1 point for identifying from the graph the correct value of pH recorded at Station ALOHA in 2005)
8.08 (+/- 0.02)

(1 point for correctly predicting the effect of an increase in concentration of $\mathrm{CO}_{2}$ in the ocean)

- Oceanic $\mathrm{CO}_{2}$ will increase.

- Dissolved oceanic $\mathrm{CO}_{2}$ will increase.

Based on the data, identify the relationship in the concentration of atmospheric $\mathrm{CO}_{2}$ and the pH of the ocean water.
(1 point for correctly identifying the relationship between the concentration of atmospheric $\mathrm{CO}_{2}$ and the pH of ocean water based on data)

- As atmospheric $\mathrm{CO}_{2}$ increases, pH decreases.

- As more $\mathrm{CO}_{2}$ dissolves in the water, it becomes more acidic/less alkaline.

- As atmospheric $\mathrm{CO}_{2}$ increases, $\mathrm{H}_{3} \mathrm{O}^{+}$or $\mathrm{H}^{+}$ions increase.

(l point for the correct balanced chemical equation that represents the reaction between oceanic carbon dioxide and water)

bicarbonate ion)

carbonate ion)

Identify the specific environmental problem that directly results from the decrease in pH of Earth's oceans.
(l point for correctly identifying the specific environmental problem that directly results from the decrease in pH of Earth's oceans)
Ocean Acidification

(2 points; 1 point for correctly explaining the impact of a decrease in pH on shells or exoskeletons and 1 point for an impact on survival of organisms)

Chemical impact on shell/coral
formation

Impact on survival of organism

- Prevent the growth of new
coral/shells
- Prevent renewal/maintenance of existing coral/shells

Organisms, such as mollusks and coral, would be threatened with
- Reduced fitness/decreased number of offspring