How much earths surface is water




















Water has so many uses on Earth, such as human and animal consumption, power production, and industrial and agricultural needs. Precipitation—in the form of rain and snow—also is an important thing to understand. It is the main way that the water in the skies comes down to Earth, where it fills the lakes and rivers, recharges the underground aquifers, and provides drinks to plants and animals.

Different amounts of precipitation fall on different areas of the Earth at different rates and at various times of the year. One problem facing the cycle of water on Earth is water contamination. Chemicals that go into the water often are very difficult, if not impossible, to remove. One potential source of contamination of water is runoff, the overland flow of water.

While precipitation causes the runoff to occur, stripping vegetation from land can add to the runoff in a particular area. The sediment and soil from these areas, not to mention any pesticides or fertilizers that are present, are washed into the streams, oceans, and lakes.

What happens to the rain after it falls depends on many factors, such as the intensity and duration of rainfall, the topography of the land, soil conditions, amount of urbanization, and density of vegetation.

A common misconception about rain that it is tear-shaped, when in actuality it is shaped more like a hamburger bun. Rain drops also are different sizes, due to the initial difference in particle size and the different rate of coalescence. Glaciers and icecaps are referred to as storehouses for fresh water. They cover 10 percent of the world's land mass. These glaciers are primarily located in Greenland and Antarctica. The glaciers in Greenland almost cover the entire land mass.

Glaciers begin forming because of snowfall accumulation. When snowfall exceeds the rate of melting in a certain area, glaciers begin to form. This melting occurs in the summer. The weight of snow accumulating compresses the snow to form ice. Because these glaciers are so heavy, they can slowly move their way down hills.

Glaciers affect the topography of the land in some areas. Ancient glaciers formed lakes and valleys. The Great Lakes are an example of this. Glaciers range in length from less than the size of a football field to hundreds of miles long.

They also can reach up to 2 miles thick. 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. 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 U. It is available in over 30 languages and also in an interactive version made for online.

We also offer three age-related versions of an interactive versions. Earth's water is always in motion, 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. Skip to main content. Search Search. Water Science School. How Much Water is There on Earth? Where is Earth's Water? Learn more. The Water Cycle Learn more. Water Basics by Topic Learn more.

All Earth's water, liquid fresh water, and water in lakes and rivers. Learn more at the Water Science School.

Related Water Science School pages:. Date published: June 6, Filter Total Items: 5. Year Select Year Apply Filter. Date published: November 6, Note: This section of the Water Science School Date published: September 20, Date published: September 25, Date published: June 8, Attribution: Water Resources.

Below are multimedia items associated with water basics. Filter Total Items: 4. List Grid. October 16, The Natural Water Cycle 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. The ground stores huge amounts of water and it exists to some degree no matter where on Earth you are.

Lucky for people, in many places the water exists in quantities and at depths that wells can be drilled into the water-bearing aquifers and withdrawn to server the many needs people have. Freshwater on the land surface is a vital part of the water cycle for everyday human life. On the landscape, freshwater is stored in rivers, lakes, reservoirs, and creeks and streams. Most of the water people use everyday comes from these sources of water on the land surface.

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. Glaciers are a big item when we talk about the world's water supply. Almost 10 percent of the world's land mass is currently covered with glaciers, mostly in places like Greenland and Antarctica. You can think of a glacier as a frozen river, and like rivers, they "flow" downhill, erode the landscape, and move water along in the Earth's water cycle.

The U. This photograph depicts several examples of geological features along the California coastline that are shaped by varied coastal processes. The gently sloping beach, stark bluffs, and presence of smooth rocks suggests that the coastal processes shaping this coastline are complex.

Imperial Geyser looking south. This hot spring pool is about 30 m about ft across and contains alkaline-Cl waters with a steam vent in the pool and mudpots outside the pool area in the upper right part of this photo. Steamboat Geyser erupts in the golden light of sunrise on July 18th, The water-dominated part of a Steamboat eruption usually lasts anywhere from 3 to 90 minutes.

Afterwards, a steam-dominated phase continues for many hours. Skip to main content. Search Search. Water Science School. Where is Earth's Water? How much water is there? Earth's Water. The Water Cycle Where to begin? Water Basics by Topic Topics. Left bar: All water, freshwater and saline , on, in, and above the Earth. Center bar: All freshwater Right bar: Only the portion of freshwater residing in surface water rivers and lakes, etc , snow and ice, and relatively-shallow ground water.

Below are other science topics associated with Earth's water. Date published: November 13, Filter Total Items: Year Select Year



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