Final answer:
High-latitude oceans are being affected by global warming and climate change, leading to shifts in marine populations, threats to coral reefs, and changes in plankton and fish distributions.
Step-by-step explanation:
High-latitude oceans are experiencing changes due to global warming and climate change. The increase in ocean temperatures is triggering shifts in marine populations and affecting various ecosystems. For example, rising temperatures are causing coral reefs to be threatened and are causing changes in plankton populations and fish distributions in the northern oceans. Additionally, global warming has the potential to raise ocean levels and jeopardize freshwater sources.