premise: In particular, carbon dioxide levels in the atmosphere and changes in the salinity of the ocean water are also important in causing these climate changes.
hypothesis: Ocean acidification occurs when excess carbon dioxide in the atmosphere causes the oceans to become acidic.
hypothesis_graph_structure: Ocean acidification<>occurs<>when excess carbon dioxide in the atmosphere causes the oceans to become acidic$$$excess carbon dioxide in the atmosphere<>causes<>the oceans to become acidic$$$the oceans<>to become<>acidic