Example: Long Description of the Water Cycle Diagram – USGS

Ocean and Atmosphere

On the left side, the ocean occupies the largest water pool. Two ocean layers are identified: a surface “mixed zone” and a deeper “deep-water zone.” Water evaporates from the ocean surface into atmospheric moisture. Moisture is transported over land by wind. Precipitation falls over both ocean and land as rain or snow.

Land Surface Processes

As moist air moves inland, precipitation falls on mountains, forests, grasslands, urban areas, and agricultural landscapes. Some precipitation becomes runoff, flowing downslope into streams and rivers. Some collects in lakes—shown as either fresh or saline—and some accumulates in wetlands, depicted as fresh or brackish environments. Water also moves downhill through streamflow to closed basins, where no rivers exit to the ocean.

Urban regions show domestic water use, urban runoff, and municipal water use, all ultimately contributing to surface waters or returning treated water back into systems. Industrial zones depict industrial water use, which connects to rivers or groundwater.

Snow, Ice, and High-Elevation Storage

Mountainous regions to the upper right contain ice sheets, glaciers, snowpack, and snowmelt. Snow and ice slowly release meltwater into surface streams and groundwater. Some meltwater contributes to reservoirs—artificial storage used for municipal, industrial, agricultural, and ecological needs. Cold-region soils show permafrost, inhibiting deep infiltration of water.

Evapotranspiration and Soil Moisture

Across vegetated landscapes, arrows indicate evapotranspiration, the combined process of water evaporating from soil and transpiring from plants. Soil moisture pools feed vegetation and contribute to groundwater recharge.

Rivers and Human Water Use

A network of rivers flows from mountains toward the ocean. Along these rivers are icons for grazing water use, agricultural water use, and industrial water use. Some water is diverted for irrigation, some infiltrates into soils or shallow aquifers, and some returns to rivers as runoff. River water eventually discharges into the ocean as streamflow to ocean.

Groundwater and Subsurface Processes

The bottom half of the diagram shows a large cross-section of groundwater stored within porous rock and sediments. Arrows indicate how precipitation infiltrates downward as groundwater recharge. Additional arrows show groundwater discharge to the ocean, connecting the aquifer to the coastal ocean system. The groundwater body extends across the entire landscape, underlying mountains, valleys, forests, urban centers, and agricultural fields.

Overall Movement

A small inset in the lower right provides a simplified schematic illustrating cyclical flow: evaporation, atmospheric transport, precipitation, infiltration, runoff, streamflow, and groundwater exchange.

This long description was created with assistance from ChatGPT (OpenAI), then reviewed and edited for accuracy and accessibility.