The biosphere of the planet is presented in the form of an organized shell of the earth's crust. Its boundaries are mainly determined by the field of the existence of life. The substance of the shell has a heterogeneous physico-chemical composition. Living, biogenic, inert, biocosal, radioactive substance, substance of cosmic nature, scattered atoms - this is what the biosphere consists of. The main difference between this shell in its high organization.
The world water cycle is due to the influence of the energy of the sun. Its rays fall on the earth's surface, transmitting its H2O energy, heating it, and turn it into steam. Theoretically, given the average evaporation rate per hour, over the course of a thousand years, the entire oceans can travel in the form of steam.
Natural mechanisms form large volumes of atmospheric fluid, transfer them to sufficiently large distances and return to the planet in the form of
precipitation. Precipitation falling to the Earth, fall into the river. They flow into the oceans.
There are small and large water cycles. Small due to rainfall in the oceans. A large water cycle is associated with precipitation on land.
Every year, about one hundred thousand cubic meters of moisture are spilled on the ground. Due to it, lakes, rivers, seas are replenished, moisture also penetrates into the rocks. A certain fraction of these waters evaporates, and part returns to the oceans and seas. A number of living organisms and plants use for growth and nutrition.
The water cycle contributes to the hydration of artificial and natural land ecosystems. The closer the area is to the ocean, the more rainfall. From land, moisture constantly returns to the ocean. A certain volume evaporates, especially in forest areas. Part of the moisture is collected in the rivers.
The water cycle requires a significant amount of energy. About a third of the total amount received from the Sun is spent on the entire process. Before the development of civilization, the water cycle was balanced: the same amount of water got into the ocean as it evaporated. With a constant climate, there would be no shallowing of rivers and lakes.
With the development of civilization, the water cycle began to break. Watering crops contributed to increased evaporation. In the southern regions there was a significant shallowing of the rivers. So, over the past thirty years, the Amu Darya and Syr Darya brought very little water to the Aral Sea, as a result, the water level in it also dropped significantly. At the same time, the appearance of an oil film on the surface of the oceans reduced evaporation.
All these factors negatively affect the state of the biosphere. Not only southern areas are affected. Serious changes are noted in the northern regions. More often recently, droughts have occurred, and foci of environmental disasters are forming. So, for example, in Western Europe during the last three or four years in the summer there was very hot weather. Although in the past the climate in these areas was very mild. As a result of too much temperature rise, forest fires often began to occur.