American Meteorological Society Certification (AMS) Practice

Surface runoff refers to the movement of water over the land's surface when excess water from rainfall, melting snow, or other sources flows towards rivers, lakes, and oceans. It is an important part of the hydrological cycle, as it contributes to the replenishment of water bodies and helps transport nutrients and sediments.

The correct response identifies this process accurately: surface runoff is the water that travels above ground as it flows towards larger bodies of water due to gravity. This can occur when the ground is saturated, impermeable, or when precipitation rates exceed absorption capacities.

In contrast, other options describe different processes related to water movement. For instance, evaporation involves water transitioning from liquid to vapor, underground water movement pertains to groundwater flow, and condensation refers to water vapor turning into liquid on surfaces like leaves. These processes, while relevant to the broader context of the water cycle, do not define surface runoff, which specifically involves water traveling over land surfaces.