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? The answer is that there is more to our water supply than just surface water, there is also plenty of water beneath our feet. Even though you may only notice water on the Earth's surface, there is much more freshwater stored in the ground than there is in liquid form on the surface. In fact, some of the water you see flowing in rivers comes from seepage of groundwater into river beds.
Water from precipitation continually seeps into the ground to recharge aquifers , while at the same time water in the ground continually recharges rivers through seepage. Humans are happy this happens because we make use of both kinds of water. In the United States in , we used about billion gallons 1, billion liters of surface water per day,and about Although surface water is used more to supply drinking water and to irrigate crops, groundwater is vital in that it not only helps to keep rivers and lakes full, it also provides water for people in places where visible water is scarce, such as in desert towns of the western United States.
Without groundwater, people would be sand-surfing in Palm Springs, California instead of playing golf. For a detailed explanation of where Earth's water is, look at the data table below. Notice how of the world's total water supply of about Not only is the reef the largest living structure on Earth, but it is also visible from space.
In short: a lot. Tiny photosynthetic organisms, known as phytoplankton, help to turn sunlight into oxygen, just like plants do on land. Plankton sinking as marine snow is also an important food source for deep sea organisms. Physical forces separate water of different temperatures with warm water rising and cold, denser water sinking.
Cold dense water travels along the seafloor. When exploring the deep waters of our oceans, ROV Hercules brings its own lighting system. Since , we have mapped over 96, square miles , square kilometers of the seafloor in the Atlantic, Gulf of Mexico, Caribbean Sea, and the Pacific Ocean which is 0. Thankfully many organizations are working toward the goal of a global ocean map. Measuring in at feet 68 meters , our exploration vessel can travel 13, nautical miles 24, kilometers at 10 knots on a fill-up and spend up to 40 consecutive days at sea.
Ocean Exploration Trust. How much water is in the ocean? How many animals are believed to live in the ocean? How many shipwrecks are in the ocean? How deep can ROV Hercules explore? How deep is the ocean? How big is the ocean? What is the deepest point of the ocean? Something like ,,,,,, gallons that's million trillion gallons of the stuff roughly 1,,,,,,, liters can be found on our planet.
This water is in a constant cycle — it evaporates from the ocean, travels through the air, rains down on the land and then flows back to the ocean. About 70 percent of the planet is covered in ocean, and the average depth of the ocean is about 12, feet 3, meters.
Ninety-eight percent of the water on the planet is in the oceans, and therefore is unusable for drinking because of the salt. Less than 3 percent of the planet's water is fresh, but about 1. Another 0. Only about 0. That's still thousands of trillions of gallons, but it's a very small amount compared to all the water available.
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