August 26, 2016 23:11

Why does it rain ?

clouds, which we can observe in the sky, made up of water.At the moment when the droplets therein are large and heavy, they fall to the ground.This process we call rain.

As you remember, in biology class at school, we were an unusual phenomenon, as the water cycle in nature.Any liquid on the surface of our planet, whether it is a pool, river, sea, lake or ocean, tends to evaporate.When the sun's rays heat the water surface, it turns into a vapor state. turns out that large droplets are very small, so much so that it is not visible to the human eye.

weight of this pair is so small that it just rushes up and the wind is flying in one direction or another.Day by day, these droplets are attracted to each other and have formed a cloud.The colder air at the top, the harder, longer and darker are the drop.Therefore clouds are dark clouds.As soon as the droplets become heavy, clouds, so to speak, can not withstand their weight and let them down.Thus we can see the rain.

Fallen from the sky again, liquid p

enetrates into the soil, where the river enters the submarine, and from there - again in the rivers and oceans.Then again, the process begins the water cycle in nature ...

little interesting facts

  • If we talk about Russia, then in our country are very unevenly distributed rainfall.Their greatest number of falls in the Caucasus and on the eastern shore of the Black Sea - about 2000 millimeters.Least of all - on the northern coast of the Caspian Sea, as well as on the islands of the Arctic Ocean - no more than 200 mm.Therefore, by the way, here the air is dry and cold.
  • the wettest city in the world has long been considered Cherrapunji - a small town in the Indian state of Meghalaya.It is small, it is home to just over 10 thousand inhabitants, located at an altitude of 1313 m above sea level.The average amount of annual rainfall of 11777 mm.It is worth noting here that the rains fall only from April to September (in the remaining months of their relatively small).This is not to say that it's hot.For example, in December-January, the temperature is kept at 12 ° C, while in the summer - about 20 ° C.The soils here are very poor because they are constantly washed away by heavy rains.

Acid rain

This name can be designated absolutely all kinds of precipitation, including snow and hail, at which the decrease in pH due to air pollution acid oxides.

first term "acid rain" used the English scientist Robert Smith in the late 19th century.He described it in one of his books.But other scientists have put his theory of the existence of the phenomenon of nature called into question.But now no one doubts that it is the cause of destruction of vegetation and even some animals.In addition, this kind of rainfall significantly reduces the fertility of the soil, destroying the facades of buildings, monuments of culture, cars and so on.

known that rain water in its normal state has a slightly acid reaction due to the presence in the air of carbon dioxide.But the acid rain is formed due to the fact that the water reacts with nitrogen oxides or sulfur, which in turn contained in the air.How do they get there?Very simply - to blame a variety of plants, thermal power plants, and even ordinary cars.

As we already wrote, the phenomenon is extremely dangerous for the environment.In addition to the vegetation, it adversely affects the reservoirs, increasing the acidity in them to such an extent that the local fauna and flora simply die.However, this is not the worst thing - much worse that this affects people who drink this water afterwards or use fish for food from such a reservoir.

By the way, experts have calculated that by the end of this century, from acid rain the United States will suffer huge losses: more than $ 8 billion from the loss of crops and about $ 2 billion from the loss of forests.How to deal with this problem?To reduce the amount of harmful emissions into the atmosphere