Question

There is consensus among scientists that humans are causing the climate to warm. Why might this warming impact biological productivity in the deepest ocean zones? Use the figure below to aid in answering this question.
a world map with ocean currents flowing from the Atlantic Ocean to the Pacific Ocean back to the Atlantic Ocean. Warm surface flow areas are depicted in red and cool subsurface areas depicted in blue.
© 2016 NASA.gov


A. Warming may slow or halt the formation of cold dense water in polar regions, reducing the delivery of carbon dioxide to depth, and slowing aerobic cellular respiration and productivity in deeper zones.
B.Warming may slow or halt the formation of cold dense water in polar regions, reducing the delivery of nutrients to depth, and thereby reducing productivity in deeper zones.
C. Warming may slow or halt the formation of cold dense water in polar regions, reducing the delivery of phytoplankton to depth, and thereby reducing productivity in deeper zones.
D. Warming may slow or halt the formation of cold dense water in polar regions, reducing the delivery of well oxygenated water to depth, and thereby slowing aerobic cellular respiration and productivity in deeper zones.

Answer 1

The answer is: "Warming may slow or halt the formation of cold dense water in polar regions, reducing the delivery of nutrients to depth, and thereby reducing productivity in deeper zones."

Global warming is caused by the accumulation of greenhouse gases in the atmosphere primarily by human activity. These increases the temperature in the polar regions will warm the water (and subsequently halting the formation of cold water). The melting of ice will release nutrients and stimulate the growth of phytoplanktons, and these organisms will compete with the nutrition in the deeper zones (the phytoplanktons and algae will reduce the available nutrients for deep sea creatures) and therefore decreasing the productivity.