Final answer:
The Pacific Ocean likely has more coral reefs than the Atlantic due to its warmer temperatures, as coral reefs are sensitive to even slight temperature changes. Climate change and oceanic acidification also threaten reefs by altering seawater composition and damaging coral health.
Step-by-step explanation:
The reason that the Pacific Ocean has many more coral reefs than the Atlantic Ocean may be attributed to several environmental factors. However, warmer temperatures in the Pacific may be the significant difference, as coral reefs are quite temperature-sensitive. Only a slight increase in temperature can cause a breakdown in the symbiotic relationship between coral and algae, leading to coral bleaching. This phenomenon severely affects the reef's health and biodiversity. It's also noted that the level of tectonic activity, such as earthquakes, is not a likely reason for the difference in coral reef distribution between the two oceans.
Factors such as climate change, oceanic acidification, and water pollution alter the composition of seawater, posing serious threats to coral reefs. The lower solubility of oxygen in warmer waters and increased carbon dioxide levels, which lead to acidification, are detrimental to coral health. Additionally, human activities, including agricultural runoff and overfishing, further degrade reef environments.