Hello to the solsarin site. Welcome, we’d like to look”what percentage of all water on earth is groundwater.”
Distribution of the Earth’s water
Earth is known as the “Blue Planet” because 71 percent of the Earth’s surface is covered with water. Water also exists below land surface and as water vapor in the air. Water is a finite source. The bottled water that is consumed today might possibly be the same water that once trickled down the back of a wooly mammoth. The Earth is a closed system, meaning that very little matter, including water, ever leaves or enters the atmosphere; the water that was here billions of years ago is still here now. But, the Earth cleans and replenishes the water supply through the hydrologic cycle.
The earth has an abundance of water, but unfortunately, only a small percentage (about 0.3 percent), is even usable by humans. The other 99.7 percent is in the oceans, soils, icecaps, and floating in the atmosphere. Still, much of the 0.3 percent that is useable is unattainable. Most of the water used by humans comes from rivers. The visible bodies of water are referred to as surface water. The majority of fresh water is actually found underground as soil moisture and in aquifers. Groundwater can feed the streams, which is why a river can keep flowing even when there has been no precipitation. Humans can use both ground and surface water.
Distribution of the water on Earth
Ocean water: 97.2 percent
Glaciers and other ice: 2.15 percent
Groundwater,: 0.61 percent
Fresh water lakes: 0.009 percent
Inland seas: 0.008 percent
Soil Moisture: 0.005 percent
Atmosphere: 0.001 percent
Rivers: 0.0001 percent.
Where is Earth’s Water?
“Water, Water, Everywhere….”
You’ve heard the phrase, and for water, it really is true. Earth’s water is (almost) everywhere: above the Earth in the air and clouds, on the surface of the Earth in rivers, oceans, ice, plants, in living organisms, and inside the Earth in the top few miles of the ground.
For an estimated explanation of where Earth’s water exists, look at this bar chart. You may know that the water cycle describes the movement of Earth’s water, so realize that the chart and table below represent the presence of Earth’s water at a single point in time. If you check back in a million years, no doubt these numbers will be different!
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.
Here is a bar chart showing where all water on, in, and above the Earth exists. The left-side 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.
Notice how of the world’s total water supply of about 332.5 million cubic miles of water, over 96 percent is saline. And, of the total freshwater, over 68 percent is locked up in ice and glaciers. Another 30 percent of freshwater is in the ground. Fresh surface-water sources, such as rivers and lakes, only constitute about 22,300 cubic miles (93,100 cubic kilometers), which is about 1/150th of one percent of total water. Yet, rivers and lakes are the sources of most of the water people use everyday.
In the first bar, notice how only 2.5% of Earth’s water is freshwater – the amount needed for life to survive.
The middle bar shows the breakdown of freshwater. Almost all of it is locked up in ice and in the ground. Only a little more than 1.2% of all freshwater is surface water, which serves most of life’s needs.
The right bar shows the breakdown of surface freshwater. Most of this water is locked up in ice, and another 20.9% is found in lakes. Rivers make up 0.49% of surface freshwater. Although rivers account for only a small amount of freshwater, this is where humans get a large portion of their water.
Glaciers and ice caps
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 260 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.
Water on Earth is a finite source. Protecting the water means protecting all forms of the Groundwater can be found in aquifers. water found on Earth. 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.
Groundwater is the water present beneath Earth’s surface in rock and soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock become completely saturated with water is called the water table. Groundwater is recharged from the surface; it may discharge from the surface naturally at springs and seeps, and can form oases or wetlands. Groundwater is also often withdrawn for agricultural, municipal, and industrial use by constructing and operating extraction wells. The study of the distribution and movement of groundwater is hydrogeology, also called groundwater hydrology.
Typically, groundwater is thought of as water flowing through shallow aquifers, but, in the technical sense, it can also contain soil moisture, permafrost (frozen soil), immobile water in very low permeability bedrock, and deep geothermal or oil formation water. Groundwater is hypothesized to provide lubrication that can possibly influence the movement of faults. It is likely that much of Earth’s subsurface contains some water, which may be mixed with other fluids in some instances.
Groundwater is often cheaper, more convenient and less vulnerable to pollution than surface water. Therefore, it is commonly used for public water supplies. For example, groundwater provides the largest source of usable water storage in the United States, and California annually withdraws the largest amount of groundwater of all the states. Underground reservoirs contain far more water than the capacity of all surface reservoirs and lakes in the US, including the Great Lakes. Many municipal water supplies are derived solely from groundwater.
Use of groundwater has related environmental issues. For example, polluted groundwater is less visible and more difficult to clean up than pollution in rivers and lakes. Groundwater pollution most often results from improper disposal of wastes on land.
Major sources include industrial and household chemicals and garbage landfills, excessive fertilizers and pesticides used in agriculture, industrial waste lagoons, tailings and process wastewater from mines, industrial fracking, oil field brine pits, leaking underground oil storage tanks and pipelines, sewage sludge and septic systems.
Additionally, groundwater is susceptible to saltwater intrusion in coastal areas and can cause land subsidence when extracted unsustainably, leading to sinking cities (like Bangkok)) and loss in elevation (such as the multiple meters lost in the Central Valley of California). These issues are made more complicated by sea level rise and other changes caused by climate changes which will change precipitation and water scarcity globally.