Final answer:
Continents are involved in a balanced cycle of evaporation and precipitation, part of the Earth's hydrological cycle. They neither gain nor lose water permanently as the water that evaporates from one region can return as precipitation to another. The balance is influenced by geographical and climatic factors.
Step-by-step explanation:
Earth's continents are involved in a continuous cycle of water exchange through evaporation and precipitation. This natural process is part of the Earth's hydrological cycle, where water from the land and oceans enters the atmosphere through evaporation or sublimation. It then condenses into clouds and falls back to Earth as rain or snow. The amount of water involved in this cycle is significant with roughly 44,000 terawatts (TW) of energy globally going into evaporating water. This can be simplified into an estimate for how much water evaporates and precipitates by considering a single square meter of ocean surface.
Notably, the balance of evaporation and precipitation is influenced by a number of factors, including global wind circulation cells and the geographical distribution of land and oceans. For example, regions near the equator receive more rainfall due to rising and cooling air masses, while areas around 30 degrees north and south latitude are typically drier because of descending warmer air. Climate patterns are also shaped by the size of continents, major ocean currents, and mountain ranges, which can alter how much precipitation an area receives and where.
In summary, continents neither gain nor lose water permanently; rather, they are stages for the flow and transformation of water. Water that evaporates from one part of a continent will eventually return as precipitation, though not necessarily in the same location.