Fresh water resources are... General characteristics of the world's water resources

Despite the fact that about 70% earth's surface covered with water, it is still a very valuable resource. Especially when it comes to quality. What are water resources? What is their structure and world reserves? What are the most pressing water problems of our time? All this will be discussed in the article.

What are water resources?

Geographic, as is known, consists of five spheres: litho-, atmospheric-, bio-, techno- and hydrosphere. What are water resources? This is all the water that is contained in the hydrosphere. It is found in oceans and seas, lakes and rivers, glaciers and reservoirs, in the soil and in the air (in the form of water vapor).

About 70% of the earth's surface is covered with water. Only 2.5% of this volume is fresh water, which humanity needs. IN absolute values- this is at least 30 million cubic kilometers, which is thousands of times greater than the needs of world civilization. However, we should not forget that the bulk of these reserves are contained in the “ice shells” of Antarctica, the Arctic and Greenland. In addition, the state of water resources available to humans is often unsatisfactory.

Structure of planetary water resources

The planet's water resources are divided into two classes:

• waters of the World Ocean;
• terrestrial (or surface) waters.

Rivers, lakes, reservoirs and glaciers contain only four percent of the world's water reserves. Moreover, most of them (by volume) are confined specifically to glaciers. And the largest “reservoir” of fresh water on the planet is Antarctica. Underground flows also belong to the Earth's water resources, but their quantitative estimates vary greatly in numbers.

Pure is the most valuable for humans and any other living organisms. Its protection and rational use is one of the most important tasks of humanity at the present stage.

Water resource update

Features of water resources include the possibility of self-purification and renewal. However, the renewability of water depends on several factors, in particular the type of hydrological body.

For example, water in rivers is completely renewed in about two weeks, in a swamp - in five years, and in a lake - in 15-17 years. This process takes the longest time in ice sheets (on average it takes 10 thousand years), and the fastest in the biosphere. In a living organism, water goes through a full renewal cycle in a few hours.

Distribution of water resources by macroregion and country

The Asian region leads the world in terms of total water resources. Follows him South America, North America and Europe. The poorest corner of the planet in terms of water reserves is Australia.

However, there is one important nuance here. So, if you calculate the volume of water reserves per capita of a continent or part of the world, you get a completely different picture. With this calculation, Australia comes out on top, but Asia comes in last. The thing is that in Asia the population is growing at a rapid pace. Today it has already reached the milestone of four billion people.

Which countries don't have to worry about water? Below are the top five states with the largest fresh water reserves. This:

1. Brazil (6950 km 3).
2. Russia (4500 km 3).
3. Canada (2900 km 3).
4. China (2800 km 3).
5. Indonesia (2530 km 3).

It is worth noting the uneven distribution of water resources on Earth. Thus, in the equatorial and temperate climate zones they are even found in abundance. But in the so-called “arid” (tropical and subtropical climate) the population experiences an acute shortage of life-giving moisture.

Water resources and people

Water is in demand in everyday life, energy, industry, and recreation. The use of this resource may be accompanied by its extraction from a natural source (for example, from a river bed) or without it (for example, for the operation of water transport).

The largest consumers of water resources are:

• Agriculture;
• industrial and energy enterprises;
• communal sphere.

The volumes of municipal water consumption are constantly growing. According to environmentalists, in large metropolitan areas economically developed countries one person uses at least 300 liters of liquid daily. This level of consumption may lead to a shortage of this resource in the near future.

Pollution and depletion of world waters

Pollution of water resources is very acute. Today it has reached catastrophic levels in some regions of the planet.

Every year, millions of tons of chemicals, oil and petroleum products, phosphorus compounds, and municipal solid waste enter the World Ocean. The latter form huge ones out of garbage. The waters of the Persian Gulf, North and Caribbean seas are very polluted with oil. Already about 3% of the surface of the North Atlantic is covered with an oil film, which has a detrimental effect on living organisms of the ocean.

A big problem is also the reduction of the planet's water resources. However, the deterioration of the quality of life-giving moisture is no less dangerous. After all, one cubic meter Untreated sewage can enter the natural riverbed and spoil tens of cubic meters of clean water.

In developing countries of the world, according to statistics, from poor quality drinking water every third resident suffers. It is the main cause of many diseases in the arid zone of Africa and Latin America.

Main types and sources of pollution of world waters

In ecology, water pollution is understood as exceeding the maximum permissible concentrations of substances contained in them (harmful chemical compounds). There is also such a thing as depletion of hydro resources - deterioration in water quality due to constant activity.

There are three main types of water pollution:

• chemical;
• biological;
• thermal;
• radiation.

The role of a pollutant can be any substance that enters a hydrological body due to human activity. At the same time, this substance significantly worsens the natural quality of water. One of the most dangerous modern pollutants is oil and its products.

Sources of pollution can be permanent, periodic or seasonal. They can be of both anthropogenic and natural origin, be point, linear or areal.

The largest source of pollution are the so-called ones, that is, those that are formed as a result of industrial, construction or communal human activities. They are usually oversaturated with harmful organic and inorganic substances, heavy metals and microorganisms. There are industrial (including mine), municipal, agricultural and other types of wastewater.

Characteristics of water resources in Russia

Russia is one of the countries in the world that does not experience water shortages. The country's modern water resources are 2.5 million rivers and watercourses, about two million lakes and hundreds of thousands of swamps. The territory of Russia is washed by twelve seas. A huge amount of fresh water is stored in glaciers (mountain and polar).

To improve water supply, thousands of reservoirs of various sizes have been created on the territory of our state. In total, they contain about 800 km 3 of fresh water. These objects not only serve as artificial reservoirs of a valuable natural resource, but also regulate the regime of rivers and prevent floods and floods. Thus, their importance cannot be overestimated.

Among the main problems of water resources in Russia, the following should be highlighted:

• irrational water use;
• deterioration in the quality of drinking water;
• unsatisfactory condition of waterworks and hydraulic structures.

Finally...

What are water resources? This is all the water that is contained in the hydrosphere. Countries such as Brazil, Russia, Canada, China, Indonesia and the USA have the largest reserves of water resources.

In modern realities, the problem of pollution and irrational use of world waters is becoming very urgent, and in some regions - especially acute. Its solution is impossible without consolidating the efforts of all countries on the planet and effectively implementing joint global projects.

Water resources- This is fresh water suitable for consumption, contained in rivers, lakes, glaciers, and underground horizons. Atmospheric vapors, ocean and sea salt waters are not yet used in the economy and therefore account for potential water resources.

Types of water resources

• surface water (oceans, seas, lakes, rivers, swamps)- the most valuable source of fresh water, but the whole point is that these objects are distributed quite unevenly over the Earth’s surface. Thus, in the equatorial zone, as well as in the northern part of the temperate zone, water is in excess (25 thousand m 3 per year per person). And the tropical continents, which consist of 1/3 of the land, are very acutely aware of the shortage of water reserves. Based on this situation, their agriculture develops only under the condition of artificial irrigation;
• groundwater ;
• reservoirs created artificially by man ;
• glaciers and snowfields (frozen water of glaciers in Antarctica, the Arctic and snowy mountain peaks). This is where most of the fresh water is found. However, these reserves are practically unavailable for use. If all the glaciers are distributed over the Earth, then this ice will cover the earth with a ball 53 cm high, and by melting it, we thereby raise the level of the World Ocean by 64 meters;
• moisture what is found in plants and animals;
• vapor state of the atmosphere.

Water resources of the Russian Federation

When thinking about the water resources of Russia, first of all, we should note the rivers. Their volume is 4,270 km 3 . There are 4 water basins on the territory of Russia:

• the seas of the Northern and Arctic Oceans, as well as the large rivers flowing into them (Northern Dvina, Pechora, Ob, Yenisei, Lena, Kolyma);
• seas Pacific Ocean(Amur and Anadyr);
• seas Atlantic Ocean(Don, Kuban, Neva);
• the internal basin of the Caspian Sea and the flowing Volga and Ural.

Half of all fresh water in the country comes from lakes. Their number in the country is approximately 2 million. Of these, the largest ones are:

• Baikal;
• Ladoga;
• Onega;
• Taimyr;
• Khanka;
• Vats;
• Ilmen;
• White.

A special place should be given to Lake Baikal, because 90% of our fresh water reserves are concentrated in it.

Lakes of the Russian Federation are used for irrigation and as sources for water supply. Some of the listed lakes have a decent supply of medicinal mud and therefore are used for recreational purposes.

The swamps of Russia also play an important role, although many people disrespect them by draining them. Such actions lead to the death of entire huge ecosystems, and as a result, rivers do not have the opportunity to cleanse themselves naturally. Swamps also feed rivers and act as their controlled object during floods and floods. And of course, swamps are a source of peat reserves.

The total volume of annually renewable water resources in Russia (river flow) is estimated at 4270 km³/year, which is taken as the starting point for assessing the country’s water supply. Among the countries of the world in terms of the total value of renewable water resources, Russia ranks second after Brazil.

An important indicator for assessing water resources is water availability (specific value of natural average annual flow per unit area and per inhabitant). Russia's water supply per unit area is approximately 250 thousand m3/year, which is much higher compared to any of the neighboring republics (except Georgia). According to this indicator, Russia occupies a somewhat more modest place in the world than in terms of the total volume of river flow, significantly (3 times) inferior to Brazil and Norway, noticeably inferior to India, and is almost on the same level with the USA, China and Canada.

Features of the distribution of water resources in Russia.

Russia is very rich in water resources. In most of the country, more precipitation falls than can evaporate, and this has led to an abundance of surface water: swamps, lakes and rivers. Most regions of the country do not lack fresh water, but the internal distribution of water resources in Russia is extremely uneven. There is a huge gap between regions in terms of total runoff. Thus, the Far East has 1812 km³/year on its territory, and the Central Black Earth region only 21.0 km³/year. Hence, the specific water availability differs sharply.

Rivers Russia belongs to the basins of three oceans: the Arctic, Pacific and Atlantic, some to the endorheic basin of the Caspian Sea. Most of the rivers are fed by melt water, which is responsible for the phenomenon of annual floods (river floods in the spring). Some rivers of Siberia and Far East The main food is obtained in summer from rainwater. The total length of Russian rivers is 2.3 million km, and the volume of annual flow is 4000 cubic meters. km.

Rivers are the basis of Russia's water fund. Over 120 thousand rivers more than 10 km long flow through its territory; the number of small rivers is much greater. The sections of rivers favorable for navigation have a length of about 400 thousand km. The basins of the seas of the Arctic Ocean include such large rivers as the Northern Dvina, Pechora, Ob, Yenisei, Lena, and Kolyma. The mountains and plains of the Far East are drained by rivers flowing into the seas of the Pacific Ocean (Amur, Anadyr, etc.). The Don, Kuban, and Neva rivers flow into the seas of the Atlantic Ocean. The Volga and Ural Rivers, which flow into the Caspian Sea, belong to the internal drainage basin.

Lakes very unevenly placed. There are especially many of them where there is a favorable combination of climate humidity and an abundance of lake basins. Most of the lakes are located in the northwestern part of the country, the lowlands of Central and Northeastern Siberia. Cluster of lakes in the south Western Siberia associated with poor drainage of the territory and the presence of shallow closed depressions. In the mountains, the largest lakes are of tectonic origin. The largest in Russia are Lake Ladoga, Lake Onega, the Caspian Sea (the largest lake in the world) and Baikal. The economic importance of lakes is not as great as that of rivers, although their water reserves are important for both the population and industry.

The groundwater- the most important sources of drinking water. The artesian basins (West Siberian, Moscow, etc.) have the largest reserves in Russia. Mineral springs (North Caucasus) are of great health value.

In Russia, a significant increase in the use of groundwater for domestic and drinking water supply is envisaged (currently, almost 65% of large cities use surface water, including Moscow, St. Petersburg, Nizhny Novgorod and etc.).

Currently, 40 large reservoirs with a volume of more than 1 km³ have been created in Russia, not counting many small ones, with a total volume of 892 km³ of water. The largest volume of fresh water is contained in the reservoirs of Eastern Siberia, the smallest in the Central, Central Chernozem and Volga-Vyatka regions. The Bratsk Reservoir ranks second in the world after the African Lake Victoria. The largest reservoirs in the world also include the Krasnoyarsk, Zeyskoye, Ust-Ilimskoye, and Samara reservoirs.

If you look at our planet from space, the Earth appears as a blue ball completely covered with water. And the continents are like small islands in this endless ocean. This is understandable. Water occupies 70.8% of the planet's surface, leaving only 29.2% of land. The watery shell of our planet is called the hydrosphere. Its volume is 1.4 billion cubic meters.

Water appeared on our planet about 3.5 billion years ago in the form of vapor that was formed as a result of degassing of the mantle. Currently, water is the most important element in the Earth's biosphere, since it cannot be replaced by anything. Fortunately, water resources are considered inexhaustible because scientists have come up with a way to desalinate salt water.

The main purpose of water as a natural resource is to support the life of all living things - plants, animals and humans. It is the basis of all life on our planet, the main supplier of oxygen in important process on Earth - photosynthesis.

Water - most important factor climate formation. By absorbing heat from the atmosphere and releasing it back, water regulates climate processes.

It is impossible not to note the role of water sources in the modification of our planet. From time immemorial, people have settled near reservoirs and water sources. Water serves as one of the main means of communication. There is an opinion among scientists that if our planet were entirely dry land, then, for example, the discovery of America would be delayed for several centuries. And we would hardly have learned about Australia for another 300 years.

Types of Earth's water resources

The water resources of our planet are the reserves of all water. But water is one of the most common and most unique compounds on Earth, since it is present in three states at once: liquid, solid and gaseous. Therefore, the Earth's water resources are:

. Surface waters (oceans, lakes, rivers, seas, swamps)

. The groundwater.

. Artificial reservoirs.

. Glaciers and snowfields (frozen water from glaciers in Antarctica, the Arctic and highlands).

. Water contained in plants and animals.

. Atmospheric vapors.

The last 3 points relate to potential resources, because humanity has not yet learned to use them.

Fresh water is the most valuable; it is used much more widely than sea, salt water. Of the total water reserves in the world, 97% of water comes from seas and oceans. 2% of fresh water is contained in glaciers, and only 1% is fresh water reserves in lakes and rivers.

Use of water resources

Water resources are the most important component of human life. People use water in industry and at home.

According to statistics, most water resources are used in agriculture (about 66% of all fresh water reserves). About 25% is used by industry and only 9% goes to meet the needs of utilities and households.

For example, to grow 1 ton of cotton, about 10 thousand tons of water are needed, for 1 ton of wheat - 1,500 tons of water. To produce 1 ton of steel, 250 tons of water are required, and to produce 1 ton of paper, at least 236 thousand tons of water are needed.

A person needs to drink at least 2.5 liters of water per day. However, on average per 1 person per major cities spend at least 360 liters per day. This includes the use of water in sewers, water supply, for watering streets and extinguishing fires, for washing vehicles, etc., etc.

Another option for using water resources is water transport. Every year, over 50 million tons of cargo are transported across Russian waters alone.

Don't forget about fisheries. Breeding marine and freshwater fish plays an important role in the economies of countries. Moreover, fish farming requires clean water, saturated with oxygen and free of harmful impurities.

An example of the use of water resources is also recreation. Who among us doesn’t like to relax by the sea, barbecue on the river bank or swim in the lake? In the world, 90% of recreational facilities are located near water bodies.

Water conservation

Today there are only two ways to preserve water resources:

1. Preservation of existing fresh water reserves.

2. Creation of more advanced collectors.

The accumulation of water in reservoirs prevents its flow into the world's oceans. And storing water, for example, in underground cavities, allows you to protect water from evaporation. The construction of canals allows us to solve the issue of delivering water without it seeping into the ground. New methods of irrigating agricultural land are also being developed that make it possible to use wastewater.

But each of these methods has an impact on the biosphere. Thus, the reservoir system prevents the formation of fertile silt deposits. The canals impede the replenishment of groundwater. And water filtration in canals and dams is the main risk factor for swamps, which leads to disturbances in the planet’s ecosystem.

Today, the most effective measure for protecting water resources is the wastewater treatment method. Various methods can remove up to 96% harmful substances of water. But this is often not enough, and the construction of more advanced treatment facilities often turns out to be economically unprofitable.

Water pollution problems

Population growth, development of production and agriculture - these factors have led to a shortage of fresh water for humanity. The share of polluted water resources is growing every year.

Main sources of pollution:

. Industrial wastewater;

. Wastewater utility routes;

. Drains from fields (when the water is oversaturated with chemicals and fertilizers);

. Burial in reservoirs radioactive substances;

. Drains from livestock complexes (such water contains a lot of biogenic organic matter);

. Shipping.

Nature provides for the self-purification of reservoirs, which occurs due to the water cycle in nature, due to the life activity of plankton, irradiation with ultraviolet rays, and the sedimentation of insoluble particles. But all these processes can no longer cope with the mass of pollution that human activity brings to the planet’s water resources.

Water resources are the reserves of surface and groundwater located in water bodies that are used or can be used.
Water occupies 71% of the Earth's surface. 97% of water resources are salt water and only 3% are fresh water. Water is also found in soil and rocks, plants and animals. A large amount of water is constantly in the atmosphere.
Water is one of the most valuable natural resources. One of the main properties of water is its irreplaceability. In itself, it has no nutritional value, but it plays an exceptional role in metabolic processes that form the basis of the life activity of all life on Earth, determining its productivity.
Daily human need for water in normal conditions is about 2.5 liters.
Water has a high heat capacity. Absorbing a huge amount of thermal cosmic and intraterrestrial energy and slowly releasing it, water serves as a regulator and stabilizer of climate processes, softening strong temperature fluctuations. Evaporating from water surfaces, it turns into a gaseous state and is transported by air currents to various regions of the planet, where it falls in the form of precipitation. Glaciers have a special place in the water cycle, since they retain moisture in a solid state for a very long time (thousands of years). Scientists have concluded that the water balance on Earth is almost constant.
For many millions of years, water activates soil formation processes. It greatly cleanses the environment by dissolving and removing contaminants.
A lack of water can slow down economic activity and reduce production efficiency. In the modern world, water has acquired independent importance as an industrial raw material, often scarce and very expensive. Water is mandatory component almost all technological processes. Water of special purity is needed in medicine, food production, nuclear technology, semiconductor production, etc. Huge amounts of water are spent on people's domestic needs, especially in big cities.
The predominant part of the earth's waters is concentrated in the World Ocean. This is a rich storehouse of mineral raw materials. For every 1 kg of ocean water there are 35 g of salts. Sea water contains more than 80 elements of the D.I. Periodic Table. Mendeleev, the most important of which for economic purposes are tungsten, bismuth, gold, cobalt, lithium, magnesium, copper, molybdenum, nickel, tin, lead, silver, uranium.
The world ocean is the main link in the water cycle in nature. It releases most of the evaporated moisture into the atmosphere. Absorbing a huge amount of thermal energy and slowly releasing it, ocean waters serve as a regulator of climate processes on a global scale. The heat of the oceans and seas is spent on maintaining the vital activity of marine organisms, which provide food, oxygen, medicines, fertilizers, and luxury goods to a significant part of the planet's population.
Aquatic organisms inhabiting surface layer The oceans provide the return of a significant part of the planet's free oxygen to the atmosphere. This is extremely important, since motor vehicles and oxygen-intensive metallurgical and chemical production often consume more oxygen than the nature of individual regions can compensate.
Fresh waters on land include glacial, underground, river, lake, and swamp waters. Renewable resource strategic importance V last years becomes drinking water good quality. Its shortage is explained by a significant deterioration in the general environmental situation around the sources of this resource, as well as tightening worldwide requirements for the quality of consumed water, both for drinking and for high-tech industries.
The bulk of fresh water reserves on land are concentrated in the ice sheets of Antarctica and the Arctic. They represent a huge reservoir of fresh water on the planet (68% of all fresh water). These reserves are preserved for many millennia.
By chemical composition underground waters are very different: from fresh to highly concentrated waters minerals.
Fresh surface water have a significant self-cleaning ability, which is provided by the Sun, air, micro-

roorganisms and oxygen dissolved in water. However, fresh water is becoming a major shortage on the planet.
Swamps contain 4 times more water than the world's rivers; 95% of swamp water is located in peat layers.
The atmosphere contains water mainly in the form of water vapor. Its bulk (90%) is concentrated in the lower layers of the atmosphere, up to a height of 10 km.
Fresh water is distributed unevenly across the Earth. The problem of supplying the population with drinking water is very acute and has become increasingly worse in recent years. About 60% of the Earth's surface is made up of zones where fresh water is either absent, severely deficient, or of poor quality. Approximately half of humanity experiences a shortage of drinking water.
Fresh surface waters (rivers, lakes, swamps, soil and groundwater) are subject to the most severe pollution. Most often, sources of pollution are insufficiently treated or not treated at all discharges from production facilities (including hazardous ones), discharges from large cities, and runoff from landfills.
Pollution environment in the Volga basin is 3-5 times higher than the national average. Not a single city on the Volga is provided with
quality drinking water. There are many environmentally hazardous industries and enterprises in the basin without treatment facilities.
The exploitable reserves of explored groundwater deposits in Russia are estimated at approximately 30 km/year. The degree of development of these reserves currently averages just over 30%.

...glaciers, groundwater...

Most of the world's reserves water make up salty water world ocean, the reserves of fresh water technically accessible to humans account for only 0.3% of all water resources on Earth.

World water resources - the big picture

With the Earth's water resources, the overall picture is:

• overall volume water resources is 1,390,000,000 cubic meters. km;
• less than 3% of the earth's water resources are fresh water;
• 0.3% of available fresh water is the water of rivers, lakes...ground and underground.

Parts of the hydrosphere

Stationary water resources of the world according to M. I. Lvovich:

• World Ocean:
  • Volume of water, thousand km 3 - 1,370,000;
  • Water exchange activity, number of years - 3,000.
• The groundwater :
  • Volume of water, thousand km 3 - ~ 60,000;
• Groundwater... including zones of active exchange:
  • Volume of water, thousand km 3 - ~ 4,000;
  • Water exchange activity, number of years - ~ 330.
• Glaciers:
  • Volume of water, thousand km 3 - 24,000;
  • Water exchange activity, number of years - 8,600.
• Lakes:
  • Volume of water, thousand km 3 - 230;
  • Water exchange activity, number of years - 10.
• Soil moisture:
  • Volume of water, thousand km 3 - 82;
  • Water exchange activity, number of years - 1.
• River (channel) waters:
  • Volume of water, thousand km 3 - 1.2;
  • Water exchange activity, number of years - 0.032.
• Atmospheric vapors:
  • Volume of water, thousand km 3 - 14;
  • Water exchange activity, number of years - 0.027.

Water exists in natural natural conditions in three basic states - ice, liquid and steam, due to which there is a constant circulation and redistribution of water resources - the water cycle in nature (the continuous movement of water in the hydrosphere, atmosphere, lithosphere). Under the influence of heat, liquid water evaporates, the steam, in turn, rises into the atmosphere, where it condenses and returns to the earth in the form of precipitation - rain, snow, dew... part of the water accumulates in glaciers, which in turn return part of the water again to a liquid state.

It should be noted that 98% of all fresh liquid water comes from groundwater.

Water resources and ecology

Let us note an important fact - the total amount of water in nature remains unchanged. However, it is necessary to understand that the active activities of mankind lead to environmental deterioration and upset the balance of the planet’s ecosystems, and this in turn significantly reduces the quantity and availability of clean drinking water that people need for a healthy and quality life.

In some regions of the planet, intensive human economic activity is already leading to a noticeable shortage of fresh water. This is especially noticeable in those regions that previously experienced a lack of fresh water due to natural causes.

Maintaining a system that guarantees the sustainable replenishment of clean drinking water on our planet is an important condition development of modern civilization.

And finally, some more background information.

River flow by parts of the world

• Europe:
  • Volume of annual runoff, km 3 - 2,950;
  • Drain layer, mm - 300.
• Asia:
  • Volume of annual runoff, km 3 - 12,860;
  • Drain layer, mm - 286.
• Africa:
  • Volume of annual runoff, km 3 - 4,220;
  • Drain layer, mm - 139.
• North and Central America:
  • Volume of annual runoff, km 3 - 5,400;
  • Drain layer, mm - 265.
• South America:
  • Volume of annual runoff, km 3 - 8,000;
  • Drain layer, mm - 445.
• Australia, including Tasmania, New Guinea and New Zealand:
  • Volume of annual runoff, km 3 - 1,920;
  • Drain layer, mm - 218.
• Antarctica and Greenland:
  • Volume of annual runoff, km 3 - 2,800;
  • Drain layer, mm - 2,800.
• All land:
  • Volume of annual runoff, km 3 - 38,150;
  • Drain layer, mm - 252.

Balance assessment of water resources. Sources of Water Resources

• Total river flow:
  • All land, km 3 - 38,150;
  • All land, mm - 260.
• Underground drain:
  • All land, km 3 - 12,000*;
  • All land, mm - 81.
• Evaporation:
  • All land, km 3 - 72,400;
  • All land, mm - 470.
• Precipitation:
  • All land, km 3 - 109,400;
  • All land, mm - 730.
• • All land, km 3 - 26,150;
  • All land, mm - 179.
• Surface (flood) runoff:
  • All land, km 3 - 82,250;
  • All land, mm - 551.