Where is freshwater located in the world

Did You Know. How Is Water Distributed? The ice sheet covers approximately 8. The Greenland ice sheet also contains large volumes of fresh water. Lakes and other reservoirs counteract fluctuations in river flow from one season to the next because they store large amounts of water.

Lakes contain by far the largest amount of fresh surface water. River flows can vary greatly from one season to the next and from one climatic region to another. In tropical regions, large flows are witnessed year round, whereas in drylands , rivers are often ephemeral and only flow periodically after a storm. Past data records for river flow and water levels help to predict yearly or seasonal variations, though it is difficult to make accurate longer-term forecasts. Some records in industrialised countries go back up to years.

By contrast, many developing countries started keeping records only recently and data quality is often poor. Many wetlands were destroyed or converted to other uses during the last century. Those that remain can play an important role in supporting ecosystems , preventing floods, and increasing river flows.

Ninety-six percent of liquid fresh water can be found underground. Groundwater feeds springs and streams, supports wetlands, helps keep land surfaces stable, and is a critical water resource. And, since groundwater is supplied by the downward percolation of surface water, even aquifers are happy for water on the Earth's surface.

You might think that fish living in the saline oceans aren't affected by freshwater, but, without freshwater to replenish the oceans they would eventually evaporate and become too saline for even the fish to survive. As we said, everybody and every living thing congregates and lives where they can gain access to water, especially freshwater.

Just ask the 6 billion people living on Earth! Here's a satellite picture of the world at night. The most obvious thing you can see is that people live near the coasts, which, of course, is where water, albeit saline, is located.

But the interesting thing in this picture are the lights following the Nile River and Nile Delta in Egypt the circled area. In this dry part of the world, surface-water supplies are essential for human communities. And if you check the price of lakefront property in your part of the world, it probably sells for much more than other land.

View the full image from NASA. To many people, streams and lakes are the most visible part of the water cycle. Not only do they supply the human population, animals, and plants with the freshwater they need to survive, but they are great places for people to have fun.

You might be surprised at how little of Earth's water supply is stored as freshwater on the land surface, as shown in the diagram and table below. Freshwater represents only about three percent of all water on Earth and freshwater lakes and swamps account for a mere 0. Twenty percent of all fresh surface water is in one lake, Lake Baikal in Asia. Another twenty percent about 5, cubic miles about 23, cubic kilometers is stored in the Great Lakes.

Rivers hold only about 0. You can see that life on Earth survives on what is essentially only a "drop in the bucket" of Earth's total water supply! People have built systems, such as large reservoirs and small water towers like this one in South Carolina, created to blend in with the peach trees surrounding it to store water for when they need it.

These systems allow people to live in places where nature doesn't always supply enough water or where water is not available at the time of year it is needed. The Earth is a watery place. But just how much water exists on, in, and above our planet? 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.

This bar chart shows how almost all of Earth's water is saline and is found in the oceans. Of the small amount that is actually freshwater, only a relatively small portion is available to sustain human, plant, and animal life. In the first bar, notice how only 2. The middle bar shows the breakdown of freshwater. Almost all of it is locked up in ice and in the ground. With this stunning realization comes a recognition that we have to utilize this resource very wisely.

An important first step is to educate ourselves and future generations of citizens. We can make better consumer, voter, and community member choices when we are informed about how we use resources, the ramifications of misuse, and solutions and actions to prevent fresh water issues.

This guide was developed to support teachers in teaching topics with real-world context, and provide them with the background to feel competent and comfortable when teaching about fresh water.