There are several properties of water that make earth a suitable environment for life, including the fact that as water gets colder, density increases. this increase in density causes water to sink, creating ocean currents. in what area would this happen the most? a. along all parts of the equator b. in the northern hemisphere, within the arctic circle c. in the southern hemisphere, within the tropic of capricorn d. near the equator, within the tropic of cancer