Question

which of these decreases as greenhouse gas pollution increases?

a. sea levels

b. rate of thermohaline circulation

c. rate of ice-sheet melting

d. ocean surface temperature

Explanation:

• Option A: Greenhouse gas pollution leads to global warming, causing ice sheets to melt and sea levels to rise, so sea levels increase, not decrease.
• Option B: Thermohaline circulation (ocean conveyor belt) is driven by differences in water density (from temperature and salinity). As greenhouse gases increase, global warming causes ice melting (adding fresh water, reducing salinity) and ocean warming (reducing density differences). This weakens the thermohaline circulation, so its rate decreases.
• Option C: Global warming from greenhouse gases increases the rate of ice - sheet melting, so this rate increases.
• Option D: Greenhouse gases trap heat, leading to an increase in ocean surface temperature.

Answer:

B. Rate of thermohaline circulation