Water reserves on earth and ways to reduce water hunger. What percentage of water is on earth

, streams, fresh lakes, and also in the clouds. According to various estimates, the share of fresh water in the total amount of water on Earth is 2.5-3%.

About 85-90% of fresh water is contained in the form of ice.

In connection with the increasing pollution of water sources, population growth, and the development of new territories, the task of artificially obtaining fresh water arises. This is achieved by:

desalination of sea water, including solar desalination
condensation of water vapor from the air using deep sea water;
condensation of water vapor in daily cold accumulators, in particular those of natural origin, such as caves in coastal rocks.

The latter method creates huge natural reserves of fresh water in the coastal areas of several countries, which have been recently discovered. Strata of fresh water sometimes go under the seabed, and fresh springs emerge through cracks in the impenetrable layers.

The cost of fresh water is becoming so high that the production of refrigeration units has begun, obtaining water from humid air by condensation.

The distribution of fresh water around the globe is extremely uneven. Europe and Asia, where 70% of the world's population lives, contain only 39% of river waters. Russia occupies a leading place in the world in terms of surface water resources. About 1/5 of the world's fresh water reserves and more than 4/5 of Russia's reserves are concentrated in the unique Lake Baikal alone. With a total volume of 23.6 thousand km 3, about 60 km 3 of rare purity natural water is reproduced in the lake annually.

According to the UN, more than 1.2 billion people already live in conditions of constant shortage of fresh water, about 2 billion suffer from it regularly, and by the middle of the 21st century. the number of people living with constant water shortages will exceed 4 billion people. Thus, we can talk about an impending global water crisis. In such conditions, it is likely that the main advantage of Russia in the “post-oil” period is water resources, and the production of water-intensive products may become the dominant direction of development of the Russian economy.

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See what “Fresh water” is in other dictionaries:

fresh water- Natural water with mineralization up to 1 mg/l... Dictionary of Geography

fresh water- — EN freshwater Water having a relatively low mineral content, generally less than 500 mg/l of dissolved solids. (Source: LANDY) EN bathing freshwater Freshwater in which bathing is explicitly authorized or in which bathing is not prohibited and is traditionally practiced by a large number of bathers. Water... Technical Translator's Guide

Evaporators, desalination units. P. water has always been an essential item on ships on sea voyages, but mainly only for drinking. Currently, P. water consumption on new ships has increased, thanks to realized in practice... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Ephron

This term has other meanings, see Water (meanings). Water... Wikipedia

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Imagine this. A new look at gigantic numbers and immeasurable quantities, Smith David J. If the entire history of our planet is compressed into 1 hour, then dinosaurs lived on Earth for only 3 minutes. If all the money in the world is a pile of 100 coins, then Africa will only get 3 coins. If the Sun is...

The lake contains 1/5 of all fresh water in the world and 3/4 of all fresh water in Russia. It is noteworthy that the majority of our citizens live in places where there is not enough fresh water. In total, about 8-10% of all water reserves in Russia.

Humans are 70% water. Can live 3 days without drinking fresh water. Our life activity leads to the gradual destruction of fresh water reserves. There is a lot of fresh water in Russia in lakes. Here are the largest of them: 911.0 cubic kilometers; 292.0 cubic kilometers; Lake Baikal 23000.0 cubic kilometers; Lake Khanka 18.3 cubic kilometers. Reservoirs: Rybinsk - 26.3 cubic kilometers; Samara - 58.0 cubic kilometers; Volgogradskoe - 31.4 cubic kilometers; Tsimlyanskoe - 23.7 cubic kilometers; Sayano-Shushenskoye - 31.3 cubic kilometers, Krasnoyarsk - 73.3 cubic kilometers and, accordingly, Bratskoye - 170.0. Fresh water is available in. Its reserves are also stored there. This is our reserve in case of shortage of valuable liquid.

Despite such vast reserves of water, it is used ineptly. In our country, fresh water is consumed as follows: 59% of all available fresh water is spent for industrial needs, 21% is spent for household purposes. Including for household needs, as well as for drinking. 13% is allocated for irrigating fields. And 7% remains in reserve for needs that may arise.

The above water consumption figures could be less. To do this, it is necessary to save fresh water. Such high costs are explained by water losses due to deterioration of water supply networks. Every year 9 cubic kilometers of fresh water are lost. In total, the amount of water lost in public utilities is equal to 16% of 100% of the water used annually. Water is lost and does not reach consumers. Fresh water is wasted in the fields. This is due to morally and physically outdated equipment. It has long needed to be replaced with new, more advanced equipment. The amount of clean fresh water is significantly reduced due to the discharge of waste into it. So in 2002, the total amount of waste water unsuitable for food was 54.7 cubic kilometers. These disappointing figures arise mainly for two reasons: water pollution by enterprises and wastewater discharge by housing and communal services. Although housing and communal services and enterprises should treat wastewater, they do not do this. In Europe, wastewater is treated to the maximum extent possible. In Russia, the total amount of treated wastewater in 2002 was 2.5 cubic kilometers. In other words, only 10% of all wastewater that must be treated. Such small numbers arose due to overload of treatment facilities or their complete absence.

Wastewater can be divided into several types based on its composition. These are, firstly, pollution (clay, particles of ores, acid and alkaline solutions), secondly, organic pollution (particles of wood, paper), thirdly, sewage formed through the activity of humans and other animals (fecal matter, animal parts and other waste).

Now there is no shortage of fresh water in Russia. In many countries around the world, the problem of water shortage is very acute. This is actually a serious problem. Due to the growth of large cities, housing and communal services have to spend more and more water. A lot of water is wasted on agriculture. Most of the fresh water is taken away by industry. These three industries compete with each other. A war may break out over fresh water in the near future. Industry, as you know, always receives more income than agriculture. Therefore, the latter industry is less competitive and loses in this fight. As a result, agriculture suffers. It becomes unprofitable to grow different crops. Such a country would rather buy finished agricultural products. Scientists give an interesting example. If the trend towards water shortages in the next half century does not change for the better, then in 2050, fields will have to be irrigated for a full harvest with an amount of water equal to 24 per year.

Potential water reserves of Russia

GREENPEACE monitors clean drinking water on the planet. Water shortages in Russia and the world are expected in the near future. Researchers provide the following figures. By 2050, people will be provided with four times less fresh water compared to the 20th century. Scientists have found that by the 20th century, one billion people will experience acute water shortages. The interaction between the entire landmass continued for millions of years. Currently, due to the barbaric use of a natural resource - water, the ocean does not receive enough moisture, which evaporates from the land. This is what causes the decrease in water levels in rivers. Just a few centuries ago, the interaction of water between the ocean and land was 50/50. Our civilization may soon be in danger of extinction precisely because of water shortages. Humanity can also become extinct because of dirty water. About 20 thousand people die in Russia every year. People were poisoned by water poisoned by chemicals and discharges. Many people get dangerous diseases due to poor water.

Today, according to scientists, there are no completely clean people in our country. Thus, a poison was recently discovered in the Moscow River - nitrite nitrogen. At the same time, municipal authorities argued with federal authorities about the permissible concentration of a toxic substance in the river. Although they could do the cleaning together sooner. Many water polluting companies have done a good job of this. Researchers identify three types of dirty water: Moderately polluted, polluted and dirty water. In recent years, Russian reservoirs have been divided precisely according to these three criteria. The dirtiest ones are, and. These are rivers with poor ecology, which will get worse over the years.

The problem of water shortage comes first among others. If the situation does not change, then the person will have nothing to drink. Well, then there are only three days to survive.

All water reserves on Earth can be divided into liquid (salt and fresh), solid (fresh) and

gaseous (fresh) water (Table 6.9). The total volume of water is about 1.5 billion km3. Moreover, 93.96% of water is concentrated in the seas and oceans. The high salt content (up to 35 mg/l) makes this water unsuitable for domestic needs and drinking.

Freshwater makes up less than 6% of all water resources on Earth. Scientists have calculated that the world's fresh water supply is approximately 30.3 million km3. The territory of the former USSR contains about 69 thousand km3 of fresh water. However, most of the world's fresh water reserves are concentrated in the glaciers of Antarctica, Greenland, the Arctic and other permafrost zones, which makes it inaccessible.

It is believed that only 0.2-0.3% of all water on Earth can actually be used for drinking purposes. Despite the world's relatively large reserves of fresh water, at the XXXV session of the UN General Assembly it was noted that more than 1 billion people experience an acute shortage of good-quality water for drinking and domestic purposes.

The first reason for water shortages is that sources of drinking water are extremely unevenly distributed both on Earth as a whole and in individual countries. For example, in the former USSR, 80% of fresh water is concentrated in Eastern Siberia, the Far East and the European North, where only 30% of the country's population lives and industry and agriculture are less concentrated.

Water consumption in developed countries is constantly increasing and is approaching the value of the entire freshwater resource. In Russia, this is especially noticeable in the south of the European part, where water consumption has already exceeded 2/3 of the total river flow and has had an extremely adverse effect on the water balance of the Caspian Sea.

The second most important reason for the lack of fresh water is anthropogenic. This is not an absolute decrease in the amount of water, but a decrease in its quality as a result of contamination by microorganisms and chemicals when household, fecal, industrial and agricultural wastewater enters water bodies. According to UN reports, about 1 million new chemical compounds are synthesized in the world every year, more than 15 thousand of which are very toxic. In general, up to 80% of all chemical compounds gradually enter the environment, including natural water bodies. In the world, a total of about 420 km3 of wastewater is released annually, which can lead to pollution of up to 7000 km3 of natural waters. This is 1.5 times more than the entire river flow of the former Soviet Union, which was 4,700 km3.

Due to the reduction in fresh water reserves on Earth and the decline in the quality of natural waters, humanity faces the problem of “water hunger.” This requires an intensive search for new scientific solutions aimed at providing high-quality water to the population, industry and agriculture.

To reduce “water hunger”, two main closely interrelated areas of action can be distinguished. The first direction should include maintaining the quality of natural waters, primarily the effective treatment of household wastewater before discharge into water bodies. However, an equally important problem is the fight against environmental pollution from industrial wastewater. In this area, the solution is seen in the development and improvement of methods for treating wastewater from industrial facilities, the use of “recycling water supply”, i.e. multiple reuse of purified water for technological purposes. In the future, it is possible to use “dry technologies” that do not require water and, therefore, do not lead to pollution of water bodies.

The second direction in the fight against “water hunger” involves the rational use and increase of natural water supplies. This is a strict economy of drinking water for both domestic and industrial needs and a constant fight against losses of this

the most valuable and expensive product, including using economic methods.

The water supply to the population can be increased by creating artificial reservoirs that accumulate fresh water reserves. The construction of reservoirs simultaneously solves other important national economic issues - energy, transport, industrial, agricultural, hygienic, aesthetic. Currently, dozens of large reservoirs have been created on the Volga, Angara, Irtysh and other large rivers, which also help in providing electricity. A hydroelectric power station with a capacity of about 4,100 MW was built on the Bratsk reservoir on the Angara with a volume of 169.4 km 3 .

In recent years, methods have also been developed for accumulating fresh water reserves in underground aquifers from surface runoff, including flood waters. The thickness of the earth through which surface water passes acts as a filter, which significantly improves the quality of surface water as it turns into groundwater. At the same time, in some regions, saline groundwater will be diluted with low-mineralized surface runoff filtered through the soil.

One of the hypothetical possibilities for obtaining large quantities of fresh water is the melting of the eternal ice of the Arctic, as well as icebergs. However, this creates a number of complex energy, economic, technical and environmental issues, in particular a likely significant increase in sea levels.

Why did the problem of “water hunger” arise?

Over the years of human existence, water on Earth has not decreased. However, people's need for water is increasing sharply. By consuming more and more clean water, people return to nature the polluted wastewater from industrial production, public services, and the agricultural complex. And there is less and less clean water on Earth.

Water is the most abundant substance on our planet: although in varying quantities, it is available everywhere, and plays a vital role for the environment and living organisms. Fresh water is of greatest importance, without which human existence is impossible, and nothing can replace it. Humans have always consumed fresh water and used it for a variety of purposes, including domestic, agricultural, industrial and recreational use.

Water reserves on Earth

Water exists in three states of aggregation: liquid, solid and gaseous. It forms oceans, seas, lakes, rivers and groundwater located in the upper layer of the Earth's crust and soil cover. In its solid state, it exists in the form of snow and ice in polar and mountainous regions. A certain amount of water is contained in the air in the form of water vapor. Huge volumes of water are found in various minerals in the earth's crust.

Determining the exact amount of water reserves around the world is quite difficult because water is dynamic and in constant motion, changing its state from liquid to solid to gaseous and vice versa. As a rule, the total amount of water resources in the world is estimated as the totality of all waters in the hydrosphere. This is all the free water that exists in all three states of aggregation in the atmosphere, on the Earth's surface and in the earth's crust to a depth of 2000 meters.

Current estimates have shown that our planet contains a huge amount of water - about 1386,000,000 cubic kilometers (1.386 billion km³). However, 97.5% of this volume is salt water and only 2.5% is fresh. Most of the fresh water (68.7%) is found in the form of ice and permanent snow cover in the Antarctic, Arctic, and mountainous regions. Further, 29.9% exists as groundwater, and only 0.26% of the Earth's total fresh water is concentrated in lakes, reservoirs and river systems where it is most easily available for our economic needs.

These figures were calculated over a long period of time, but if shorter periods are taken into account (one year, several seasons or months), the amount of water in the hydrosphere may change. This is due to the exchange of water between the oceans, land and atmosphere. This exchange is usually called the global hydrological cycle.

Freshwater resources

Fresh water contains a minimal amount of salts (no more than 0.1%) and is suitable for human needs. However, not all resources are available to people, and even those that are are not always suitable for use. Consider sources of fresh water:

Glaciers and snow covers cover about 1/10 of the world's land mass and contain about 70% of fresh water. Unfortunately, most of these resources are located far from populated areas and are therefore difficult to access.
Groundwater is by far the most common and accessible source of fresh water.
Freshwater lakes are mainly located at high altitudes. Canada contains about 50% of the world's freshwater lakes. Many lakes, especially those in dry areas, become salty due to evaporation. The Caspian Sea, Dead Sea, and Great Salt Lake are among the world's largest salt lakes.
Rivers form a hydrological mosaic. There are 263 international river basins on Earth, which cover more than 45% of the planet's landmass (with the exception of Antarctica).

Water resources objects

The main objects of water resources are:

oceans and seas;
lakes, ponds and reservoirs;
swamps;
rivers, canals and streams;
soil moisture;
groundwater (soil, groundwater, interstratal, artesian, mineral);
ice caps and glaciers;
precipitation (rain, snow, dew, hail, etc.).

Problems of water use

For many hundreds of years, human impact on water resources was insignificant and of an exclusively local nature. The excellent properties of water - its renewal due to the cycle and the ability to be purified - make fresh water relatively purified and possessing quantitative and qualitative characteristics that will remain unchanged for a long time.

However, these features of water gave rise to the illusion of the immutability and inexhaustibility of these resources. Out of these prejudices arose a tradition of careless use of extremely important water resources.

The situation has changed greatly over the past decades. In many parts of the world, the results of long-term and mismanagement of such a valuable resource have been discovered. This applies to both direct and indirect water use.

Around the world, over the course of 25-30 years, there has been a massive anthropogenic change in the hydrological cycle of rivers and lakes, affecting water quality and their potential as a natural resource.

The volume of water resources, their spatial and temporal distribution, are determined not only by natural climate fluctuations, as before, but now also by the types of economic activities of people. Many parts of the world's water resources are becoming so depleted and heavily polluted that they can no longer meet ever-increasing demands. It may
become a major factor hindering economic development and population growth.

Water pollution

The main causes of water pollution are:

Wastewater;

Domestic, industrial and agricultural wastewater pollutes many rivers and lakes.

Disposal of waste in seas and oceans;

Burying garbage in the seas and oceans can cause huge problems, because it negatively affects living organisms that live in the waters.

Industry;

Industry is a huge source of water pollution, producing substances harmful to people and the environment.

Radioactive substances;

Radioactive pollution, in which there is a high concentration of radiation in the water, is the most dangerous pollution and can spread into ocean waters.

Oil spill;

An oil spill poses a threat not only to water resources, but also to human settlements located near a contaminated source, as well as to all biological resources for whom water is a habitat or a vital necessity.

Leaks of oil and petroleum products from underground storage facilities;

Large quantities of oil and petroleum products are stored in tanks made of steel, which corrode over time, causing harmful substances to leak into the surrounding soil and groundwater.

Precipitation;

Precipitation, such as acid precipitation, occurs when air is polluted and changes the acidity of water.

Global warming;

Rising water temperatures cause the death of many living organisms and destroy a large number of habitats.

Eutrophication.

Eutrophication is a process of reducing the quality characteristics of water associated with excessive enrichment with nutrients.

Rational use and protection of water resources

Water resources require rational use and protection, ranging from individuals to enterprises and states. There are many ways we can reduce our impact on the aquatic environment. Here are some of them:

Saving water

Factors such as climate change, population growth and increasing aridity are increasing pressure on our water resources. The best way to conserve water is to reduce consumption and avoid increased wastewater.

At the household level, there are many ways to save water, such as taking shorter showers, installing water-saving appliances, and washing machines with low water consumption. Another approach is to plant gardens that do not require much water.

There are about 1.5 billion km3 of water on our planet and it covers more than 70% of the Earth's surface. However, fresh water accounts for only 3% of the total, namely 91 million km3. The main part of the water contained in the oceans is bitterly salty, and it is practically not applicable for economic activities without proper preparation. The main supply of fresh water is water located underground and in glaciers. Those. its extraction is difficult in both the first and second cases. But if in order to extract water from underground, it is possible to drill a water well , then the extraction of water from glaciers is practically impossible and economically unjustified. Scientists have calculated that natural ice contains more than 24 million cubic km of fresh water - this is the volume of flow of all the Earth's rivers over 500 years. If you try to evenly distribute ice over the surface of the Earth, it will cover it with a layer 53 meters thick. Rivers, lakes and usable underground freshwater account for only 0.3% of the world's free water reserves.

It is noteworthy that Lake Baikal contains a fifth of all the world's surface fresh water reserves.

Over the past 40 years, the amount of fresh water per person has decreased by more than 60%. Over the next 30 years, a further decrease in this amount by another 2 times is predicted.Agriculture is the main consumer of fresh water. It currently consumes 87% of available water. Products produced on irrigated lands are 2-5 times more expensive than those grown due to rainfall, since the cost of fuel and hydraulic structures is constantly increasing.

More than 80 countries around the world experience a constant shortage of fresh water, where together more than 2 billion people live.

Recently, Australian researchers announced that they were able to identify the existence of huge reserves of fresh water trapped below the ocean floor. Perhaps these are the resources that will be able to support future generations when existing sources dry up.Lead author of the study Vincent Postfrom Flinders University reported that, according to his colleagues, about 500 thousand cubic kilometers of water with low salinity levelswas discovered under the seabed on the continental shelfoff the coast of Australia, China, North and South America.“The volume of this water resource is a hundred times greater than the amount of fresh water extracted from the bowels of the earth in the last century, since 1900,” says Post. “Fresh water on our planet is drying up over time, so the discovery of new underground reservoirs off the coast is quite important. This means we now have another option to consider to help those suffering from drought and continental water shortages."

According to Post, his team came to this unexpected discovery after studying the seabed for scientific purposes and during geological exploration to discover oil and gas deposits. “By combining all the information we received, we came to the conclusion that fresh water lying below the seabed is a fairly common occurrence, and not an anomaly at all,” says the Australian scientist.

Such deposits are formed over hundreds of thousands of years. Their origins began when sea levels were significantly lower and those areas that are now hidden by the World Ocean were exposed to precipitation absorbed into the soil. When the polar ice sheets began to melt about 200,000 years ago, these coastlines were hidden by water, but their aquifers remain intact, protected by layers of clay and other sediment.

According to experts, extracting fresh water from such sources will cost much less than desalinating sea water. The most expensive process will be drilling, after which considerable efforts will need to be made to prevent contamination of groundwater.