Slightly more than one drop of water would fill all the rivers and lakes. It fills pores and fractures in layers of underground rock called aquifers.
Some of this water lies too far under the earth's surface to be extracted at an affordable cost. Surface-water runoff - precipitation that does not infiltrate into the ground or return to the atmosphere: streams, rivers, lakes, wetlands, and reservoirs.
Water Use in the U. More than half the people in the U. The value in the above table is near the high end of the range. Skip to main content. Earth Observatory Water Cycle Overview. Outreach , Informal , General. Water is a vital substance that sets the Earth apart from the rest of the planets in our solar system. Earth is a water planet: three-quarters of the surface is covered by water, and water-rich clouds fill the sky.
Sometimes, all three states are even present in the same time and place, such as this wintertime eruption of a geyser in Yellowstone National Park. Water vapor—and with it energy—is carried around the globe by weather systems.
This satellite image shows the distribution of water vapor over Africa and the Atlantic Ocean. Technical Announcements. Employees in the News. Emergency Management. Survey Manual. The Earth is a watery place. But just how much water exists on, in, and above our planet? Read on to find out. Spheres showing : 1 All water largest sphere over western U.
About 71 percent of the Earth's surface is water-covered, and the oceans hold about Water also exists in the air as water vapor , in rivers and lakes , in icecaps and glaciers , in the ground as soil moisture and in aquifers , and even in you and your dog.
Water is never sitting still. Thanks to the water cycle , our planet's water supply is constantly moving from one place to another and from one form to another. Things would get pretty stale without the water cycle! The globe illustration shows blue spheres representing relative amounts of Earth's water in comparison to the size of the Earth. Are you surprised that these water spheres look so small?
They are only small in relation to the size of the Earth. This image attempts to show three dimensions, so each sphere represents "volume. The smaller sphere over Kentucky represents Earth's liquid fresh water in groundwater, swamp water, rivers, and lakes.
The volume of this sphere would be about 2,, mi 3 10,, km 3 and form a sphere about Yes, all of this water is fresh water, which we all need every day, but much of it is deep in the ground, unavailable to humans. Do you notice the "tiny" bubble over Atlanta, Georgia?
That one represents fresh water in all the lakes and rivers on the planet. Most of the water people and life on earth need every day comes from these surface-water sources. The volume of this sphere is about 22, mi 3 93, km 3. The diameter of this sphere is about Yes, Lake Michigan looks way bigger than this sphere, but you have to try to imagine a bubble almost 35 miles high—whereas the average depth of Lake Michigan is less than feet 91 meters.
The vast majority of water on the Earth's surface, over 96 percent, is saline water in the oceans. The freshwater resources, such as water falling from the skies and moving into streams, rivers, lakes, and groundwater, provide people with the water they need every day to live.
Water sitting on the surface of the Earth is easy to visualize, and your view of the water cycle might be that rainfall fills up the rivers and lakes. But, the unseen water below our feet is critically important to life, also.
How do you account for the flow in rivers after weeks without rain? In fact, how do you account for the water flowing down a driveway on a day when it didn't rain?
0コメント