Water Distribution on Earth

What percentage of the Earth's surface is covered by water?

Which type of water constitutes approximately 97% of the total water on Earth?

How much of the freshwater on Earth is frozen in ice caps and glaciers?

What percentage of Earth's total water is freshwater available for use and consumption?

Which of the following best describes the makeup of surface water?

What is the approximate diameter of the spherical drop of water representing all available water on Earth?

What portion of the global water supply is groundwater used for drinking and crop irrigation?

Which form of water is NOT usable for drinking?

What percentage of the Earth's water resources is fresh water?

Which of the following best describes how water moves in the water cycle?

Where is the majority of Earth's freshwater located?

Which statement about saltwater is true?

What is the primary reason the water cycle is important to ecosystems?

What constitutes less than 1% of all freshwater on Earth?

Which of the following statements about groundwater in the western United States is accurate?

Earth's Water Distribution

Surface water: Covers about 71% of Earth's surface. Primary component is ocean water, making up approximately 97% of all water.
Freshwater: Represents just 3% of Earth's water. Significant portions are frozen in ice caps and glaciers (about 2/3 of the 3%).
Usable freshwater: Only about 1% of Earth's freshwater is readily accessible for human use. This includes groundwater (about 0.6%) and surface water (about 0.3%). Surface water consists of streams, rivers, ponds, and lakes.

Saltwater

Saline water: Over 96% of Earth's water is saltwater, not just found in oceans.
Salt concentration (ppm): Saline seas have varying salt concentrations, from 1,000 ppm to 35,000 ppm (oceans). Higher salt concentrations in some groundwater sources require treatment before consumption.

Freshwater Availability

Underground Storage: Approximately 30% of freshwater is in underground aquifers.
Frozen Freshwater: 68% of freshwater is frozen in ice caps and glaciers.
Surface Water: A small portion (about 0.3% of all of Earth's water or 0.009% of the total) makes up surface water like rivers, lakes, and streams. This represents a critical resource that needs careful management.

Water Cycle

Water's Movement: The continuous movement of water in different phases. The water cycle moves water from the Earth's surface to the atmosphere through evaporation and transpiration. Then, it travels back down to the Earth as precipitation.
Impact: Affects the weather, climates, and availability of drinking water.

Water Availability in Perspective

Large Volume but Limited Useable: While Earth appears mostly water, the amount usable for consumption is small compared to the total volume.
Volume of Water Comparison: A spherical drop of water covering the central US to represent all water available on Earth (332,500,000 cubic miles). The equivalent amount of freshwater is about the size of a small portion of Kentucky (2,551,000 cubic miles). Usable surface water like a speck of water a dot over a city like Indianapolis (22,339 cubic miles).

This quiz explores Earth's water distribution, focusing on surface water and freshwater sources. Learn about the proportions of saltwater and freshwater, as well as the availability of usable water for human consumption. Test your knowledge on the vital statistics of Earth's aquatic resources.