How much of the world is water

Glaciers melting can have a tremendous effect on the sea level. If all of the glaciers were to melt today, the sea would rise an estimated feet, according to the USGS.

Glaciers have had a tremendous effect on the formation of the Earth's surface and are still influencing the topography everyday. Groundwater is defined as water that is found beneath the surface of the Earth in conditions of percent saturation if it is less than percent saturation, then the water is considered soil moisture. Ninety-eight percent of Earth's available fresh water is groundwater.

It is about 60 times as plentiful as the fresh water found in lakes and streams. Water in the ground travels through pores in soil and rock, and in fractures and weathered areas of bedrock. The amount of pore space present in rock and soil is known as porosity. The ability to travel through the rock or soil is known as permeability.

A "high" permeability and porosity value means that the water can travel quickly. Groundwater can be found in aquifers. An aquifer is a body of water-saturated sediment or rock in which water can move readily. There are two main types of aquifers: unconfined and confined.

An unconfined aquifer is a partially or fully filled aquifer that is exposed to the surface of the land. Because this aquifer is in contact with the atmosphere, it is impacted by meteoric water and any kind of surface contamination. There is not an impermeable layer to protect this aquifer. In contrast, a confined aquifer is an aquifer that has a confining layer that separates it from the land surface. This aquifer is filled with pressurized water due to the confining layer.

If the water is pressurized at a high enough value, when a well is drilled into the confining aquifer, water rises above the surface of the ground. This is known as a flowing water well. The pressure of the water is called the hydraulic head.

Groundwater movement, or velocity, is measured in feet or meters per second.. In some areas, the bedrock has low permeability and porosity levels, yet groundwater can still travel in the aquifers. Groundwater can travel through fractures in the rock or through areas that are weathered. Limestone, for example, weathers in solution, creating underground cavities and cavern systems. At the land surface, these areas are known as "karst". The voids in the rock, created as limestone goes into solution, can cause collapses at the land surface.

These collapses are known as sinkholes. Sinkholes are often a direct conduit to the groundwater and areas where contamination can easily infiltrate the aquifers. Sinkhole areas also can have land subsidence as mass wasting occurs in areas with a sudden change in slope and contact with water.

Land subsidence may or may not be noticeable in some areas because it appears as hills and valleys due to the very large size. As groundwater becomes more of a source for drinking water, the problem of sinkholes and land subsidence could increase.

Porosity and permeability of the sediment, soil, and bedrock in the area also affects the recharge rate of the groundwater. This means that in some areas, the groundwater can be pumped out faster than it can replenish itself. This creates a number of problems. One of these problems is called "drawdown," a lowering of the aquifer near a pumping well. This can occur in areas where the well is pumping faster than the groundwater aquifer is recharged. Drawdown creates voids in the bedrock and can lead to additional land subsidence or sinkholes as there is no longer water present and the void cannot hold the weight of the material above and collapses.

Because groundwater is a very plentiful source of fresh water, it must be a protected resource. In many areas, however, groundwater is not protected. Once an aquifer is contaminated with chemicals or petroleum, it is difficult, if not impossible, to clean up. Therefore, prevention of contamination is paramount.

Karst areas pose a difficult problem because anything spilled on the surface travels quickly and easily into the aquifer.

Many times, surface water also is in direct contact with undergroundwater, and depending on if the stream is feeding the groundwater a losing stream or if the groundwater is feeding the stream a gaining stream this can create a problem with contamination of the groundwater. There is also the problem of saltwater intrusion present in coastal regions, such as Florida where over-pumping of the groundwater draws the denser saltwater up into the aquifer.

So, protection of the groundwater should be a high priority as the population on Earth continues to rise and potable water becomes a valuable resource. Protecting groundwater also means protecting surface water, rain water, and all forms of water, because water continues to cycle and recycle. Once the water is contaminated, it is difficult to ever remediate.

Water on Earth is a finite source. Protecting the water means protecting all forms of the Groundwater can be found in aquifers. Water at the surface, under the ground, in vapor form, and as precipitation. Pollution from using fossil fuels can impact all forms of water from crude oil leaks to acid rain generated from coal burning.

Acid rain falls onto the land and flows into the surface water, back into the ground, and back into the air.

It can be an endless cycle. As contamination infiltrates the water cycle, more water will be impacted. Most of the water on Earth is saline. Fresh water is and will be in demand and become a very valuable resource. Care must be taken to prevent overuse of potable water sources. Care must also be taken to protect the Earth's waters from contamination.

Water is indeed a valuable resource. Distribution of the water on Earth Ocean water: Surface waters Surface waters can be simply described as the water that is on the surface of the Earth. The water cycle The hydrologic cycle or water cycle is a graphic representation of how water is recycled through the environment. Glaciers and ice caps Glaciers and icecaps are referred to as storehouses for fresh water.

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 Of total freshwater, over 68 percent is locked up in ice and glaciers. Another 30 percent of freshwater is in the ground.

Note: Percentages may not sum to percent due to rounding. One estimate of global water distribution Percents are rounded, so will not add to Earth's water is almost everywhere: above the Earth in the air and clouds and on the surface of the Earth in rivers, oceans, ice, plants, and in living organisms. But did you know that water is also inside the Earth? Read on to learn more. Earth's water is always in movement, and the natural water cycle, also known as the hydrologic cycle, describes the continuous movement of water on, above, and below the surface of the Earth.

Water is always changing states between liquid, vapor, and ice, with these processes happening in the blink of an eye and over millions of years. Our interactive diagrams allow you to "mouse around" the parts of the water cycle and view explanations, pictures, and more. Yes, of course the most obvious fact about water is that it is wet, at least in the liquid state.

But, there are many more facts about water that make it a most fascinating substance, one that all life on and in the Earth depends on. Not only do the oceans provide evaporated water to the water cycle, they also allow water to move all around the globe as ocean currents. Oceans are the storehouses of water nature uses to run the water cycle.

Water is always changing states between liquid, vapor, and ice, with these processes happening in the blink of an eye and over. The content is provided for information purposes only.

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