AICE Marine Science Paper 2 Practice Exam

El Niño is a complex climate pattern characterized by the periodic warming of sea surface temperatures in the central and eastern Pacific Ocean. One significant ecological consequence of El Niño is the disruption of nutrient cycling, particularly in marine environments.

During an El Niño event, the warming of ocean waters inhibits the upwelling of nutrient-rich water from the deep sea. Normally, this upwelling is crucial for supporting phytoplankton growth, which forms the base of the marine food web. When this process is disrupted, there is a decrease in phytoplankton productivity, which can lead to lower fish populations and reduced overall biodiversity.

Additionally, the altered temperature and salinity levels during these events can further affect the availability of nutrients necessary for marine ecosystems. This highlights how interconnected oceanic processes are and how climate phenomena like El Niño can have cascading effects on marine life and biodiversity.