In autumn rains and precipitation are frequent. Why is it raining? Acid and radioactive rain

Why is it raining? It is unlikely that a person will begin to ask this question if the sky frowned outside the window, the first drops fell from it, but you urgently need to leave the house. In this case, people just take an umbrella and go about their business. But it is quite possible in moments of leisure, philosophizing and contemplation

think about why it rains. There are many constant processes going on in nature. One of them - its main participants: liquids of various kinds and the sun.

The luminary not only illuminates the earth, but also warms it. Water, heating up, passes into another state - gaseous. Water vapor rises. The higher the vapor rises, the colder the air surrounds them. Molecules under these circumstances, in the process of condensation, are converted into crystals, which, accumulating, form clouds and clouds. When they gain a large mass, there is a violation of their stability. Cloud clusters are no longer able to hold water, and drops begin to fall out of them. That's why it rains.

The water that falls on the surface of the earth either evaporates again, or seeps into the ground, or immediately enters the reservoir. In any case, the evaporation process starts again. It is infinite and, like everything ingenious, simple.

It is usually determined by the temperature regime in the subcloud layer, the height of the clouds and their structure. As a rule, clouds that bring precipitation have a mixed composition: ice crystals and drops of cold water. Falling down from the total mass, this mixture is transformed in conditions of either warm or frosty air. If the temperature of the subcloud layer is positive, then raindrops reach the ground. If the parameters are negative, snow falls on the ground.

The lower layers of the atmosphere also play a role. If in summer clouds form very high above the ground, in conditions of negative temperature, then the main composition of the mass consists of ice crystals. This means that snow flies out of the cloud into the subcloud layer. But when passing through warm air, snowflakes melt. Then hail falls on the ground. If they manage to melt completely, then drops of water. That's why it's snowing, raining, hail.

In the summer - every student will answer this question. Because it's warm. Why does it rain in winter? It happens that atmospheric phenomena occur with a deviation (for various reasons) from the normal course of events. For example, in winter, warm cloud clusters formed in a tropical region over the ocean or sea can enter mid-latitudes. In this case, a thaw begins, the previously fallen snow melts, and instead of snowflakes, rain falls on the ground.

This also happens in the summer. Masses of cold air are breaking through from the Arctic. Warm is pushed aside, but at the same time it forms with powerful cloudiness. Precipitation can be extremely heavy. At first it rains, then as the air cools, hail or sleet can fall. These precipitations can fall without cooling, but always in the presence of powerful clouds. If the front hangs over a certain area, the temperature of the atmosphere will drop even more, then real snow will fall on the ground.

Answer from Oksana[guru]
The sun warms the water in the ocean, in the sea, in the river, in any puddle.
Water evaporates, turns into transparent vapor and rises upward, where warm air currents carry it along, because warm air is lighter than cold air, it always tends to rush upward.
Light water vapor rises higher and higher from the earth heated by the sun, it climbs high, where it is constantly, even on the hottest summer day, very cold, like in winter.
The steam is warm, and when it touches cold air, it turns into tiny droplets of water.
The droplets are as light as fluff, they stay in the air perfectly, they float and move all the time, because everyone pushes them; new and new currents of warm air rising from the ground.
Warm air throws droplets even higher, cold air drags them down; so they fly, tiny travelers, up and down; they dance, merge together, become larger.
There are very, very many of them, and together they form a cloud.
In the upper part of the cloud, the droplets freeze - it is very cold there; they turn into ice floes, grow, become heavier, so they can no longer stay in the cloud and fall down. And when they fall, they melt, because it is much warmer below; again become droplets of water, merge together - and it rains on the earth.
It's raining because water
Constantly striving for the ground.
Because it's already cold
And in heaven, someone can not sleep.
Because falling in love with you
I got lost among the three pines,
Because, not loving the heat,
A sad autumn has come.
The author of the poems, unfortunately I do not know who ...

Answer from Elena Maksimova[newbie]
When heavy black clouds gather in the sky, people say: "It will rain." Most of the time it actually starts. But where did the clouds come from, and why does it rain from them? The reason for all this is the Sun. It heats the surface of the planet and the waters in the oceans, lakes and rivers turn into steam. It mixes with air.
Rising warm air spreads water vapor in the atmosphere. Cooling down, the air gives up part of its load, and the invisible water vapor again becomes water. Clouds form from its droplets. This process, which is opposite to evaporation, is called condensation. Inside the cloud, tiny droplets gradually grow, collecting more and more moisture. Finally, the drops become so large that they can no longer be held up by air currents and fall to the ground in the form of rain.
Evaporation continues throughout the day. Water vapor rises into the atmosphere. But in order for it to turn into clouds, consisting of the smallest droplets, solid particles are also needed, on the surface of which the vapor could condense. If there are no or very few dust particles or ice crystals in the air, condensation may not occur.
This is how events unfold on a warm summer day, when the sun shines in the bright sky in the morning, and in the afternoon clouds gather and rain falls on the ground, sometimes heavy, but short downpour. These are local rains. The rains are long, lingering, for two or three days, or even for a week, powerful air whirlwinds - cyclops - are brought from afar. The inhabitants of the European plain are showered with water that has evaporated from the surface of the Atlantic Ocean. By determining the speed of the cyclone, meteorologists can predict the time of the onset of rainy weather.
Have you ever wondered why it rains? Who is crying there in the sky? Maybe there is someone bad at this moment? So bad that you can't hold back your tears. And they drip onto the ground, breaking off the cheeks of an angel sitting on a gloomy gray cloud ... Do you know why there is different rain? In summer, the angels are happy, and their tears appear only from happiness. Therefore, such rain falls when the sun shines. And it reflects in their eyes. And from these glare, a rainbow is obtained.
And by autumn, the angels begin to feel sad, they cry more and more often and hide their eyes in the clouds... Then the tears fall to the ground sadly, quietly... This is the autumn rain. In winter, angels begin to feel sad without love... And tears, falling from their eyes down to the ground, turn into snowflakes, cold, prickly... Here they are... different rains...
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Answer from Vitaly Noroh[newbie]
water evaporates, water drips. simple

Answer from User deleted[active]
and in the high layers of the atmosphere, steam condenses into water and falls to the ground - everything is simple

Answer from Anna[guru]
Rain is the result of a complex and lengthy process involving the sun, earth and air. First, the earth is warmed by the sun. As a result, the water of the oceans, seas, lakes, as well as the moisture contained in the soil, turn into water vapor. This vapor is then mixed with air. This is how the evaporation process goes.
And then, along with lighter warm air, water vapor rises high into the sky, where they cool and turn into clouds. This process is called condensation.
What happens next with the water vapor inside the clouds. The smallest droplets of water contained in the clouds gradually grow, absorbing more and more moisture. Finally, the drops become so heavy that the air currents are unable to hold them, and they fall to the ground in the form of rain. That's why it's raining.
The process of water evaporation takes place almost around the clock, and water vapor rises. But it doesn't rain every day. Far from always invisible vapors turn into visible raindrops. This is because a certain surface is required for the condensation process to take place. If there are few or practically no dust particles in the air, then condensation does not occur. Snowflakes and ice crystals that are high in the clouds contribute to the condensation process.
If warm and cold air currents collide in the atmosphere, it will most likely lead to rain. Warm air contains a lot of moisture, which is cooled by cold air currents. Invisible vapors turn into heavy drops of water, which fall to the ground.

Rain is the most common form of precipitation. Even in elementary grades, students are told where the rain comes from. But, despite the availability of teacher explanations, there are many unclear "why". For example, why is it possible for a small cloud to pour out torrents of rain, while black clouds pass by without even splashing? Why do drops come in different sizes and how are they formed?

Rain and the water cycle

Everything starts with warmth. Solar energy causes water to evaporate from the surfaces of oceans, lakes, seas, rivers, other bodies of water, soil, and even plants. Turning into steam, it rises into the air. The force of the wind speeds up the process. Small water particles are not tangible. At high humidity (especially in the tropical zone), you can see how the bubbles circle around, not sinking, but rather, tending up.

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Causes of rain (precipitation formation)

Climatology and meteorology - sciences that are directly interested in any precipitation, distinguish 4 main reasons for the appearance of rain:

1. Ascending air movements
2. The presence of water vapor in the air, in an amount sufficient to form rain
3. Meeting of warm and cold air currents
4. Presence of elevated landforms

Ascending air movements

The sun heats the earth's surface, and moisture begins to evaporate from it. The evaporation process occurs not only directly from the soil, but also from the surface of the ocean, sea, lake, as well as from leaf blades and human skin. All the water that has evaporated while in the air. But, the heated air - in accordance with the laws of physics, begins to slowly rise up. Together with all the water it contains.

It is necessary to remember important physical concepts - relative and absolute humidity. Absolute - this is the amount of water vapor that is already - at the moment, contained in the air. Relative humidity is the amount of humidity that exists relative to what could be at a given temperature. And the last physical law - the higher the air temperature, the more water vapor it can hold in itself.

There is already some moisture in the ascending air currents. But as you move up, the temperature drops. Therefore, moisture begins to condense into clouds. When the temperature drops even lower, and the cloud can no longer hold the amount of moisture contained in it, the excess falls in the form of rain.

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The presence of water vapor in the air, in an amount sufficient to form rain

The process is similar to the one described above, only with clarifications. The rule of rain formation works if there is a place for water vapor to come from - from the surface of freshly plowed soil, a river, a lake mirror, or a leaf plate of green seedlings of cabbage and spinach. And if we are in the center of the Sahara desert, then there will be no moisture in the air, no matter how much the sun shines.

Every person has experienced this natural phenomenon. We all hid from the rain under umbrellas many times and have long been accustomed to checking if there are clouds in the sky before a walk. And the most curious are sure to ask the question, where does this rain come from?

Where does the water for rain come from in the sky?

It turns out everything is very simple. Under the influence of solar heat, the smallest droplets of water evaporate from the surface of the Earth. These droplets are very small, almost invisible to the eye, such small droplets are called water vapor.

Water evaporates from the leaves of trees, from the surface of the earth and even from the surface of our body. Most of the water, of course, evaporates in the form of steam from the water surface of rivers, lakes, seas and oceans.

Evaporation over water can be seen in the early morning, when the vapor begins to collect in droplets right above the water. And you can also see such steam when the kettle boils.

Rising higher and higher, the vapor enters the cold layers of the atmosphere and collects in water droplets and tiny ice floes. After all, the temperature at the top, where the clouds gather, is about zero degrees. The wind collects droplets into huge bizarre clouds. You can see before the rain how white clouds gather into a cloud before our eyes darken. This is because there is so much water in the sky that it blocks out sunlight.

It happens that droplets freeze due to low temperatures and, together with raindrops, fall to the ground. It's hailing.

The droplets in the cloud connect with each other, become heavier and begin to fall to the ground. So it starts to rain.

Why does it rain more often in autumn?

Rains in Russia in autumn are even less frequent than in summer. According to weather forecasters, the largest amount of precipitation falls in June. And in autumn, due to the large number of cloudy days, it seems to us that autumn is rainy.

In winter, evaporating water vapor does not even have time to gather into droplets, but immediately turns from steam into fluffy snowflakes. Yes, snowflakes are formed from steam. And then instead of rain in winter it snows.

Now you know how water gets into the atmosphere and why it rains. Once on the ground in the form of rain or snow, water goes into groundwater, into the seas, oceans, rivers, lakes, and other bodies of water, and everything starts again and again. This natural phenomenon is called the water cycle.

Without such a water cycle, our planet would turn into a lifeless desert.

You can arrange a small water cycle even at home. For this transparent cover and put on fire. You will see how the steam will rise, settle on the lid, in the form of droplets. And the drops will fall down to rise up again, turning into steam. Such a wonderful rain in a saucepan.

Meanwhile, the evaporation of water from the surface of the soil and water bodies continues. The wind knocks together small flocks of fog. A cloud forms. Tiny droplets of water vapor move randomly, sometimes they merge and become larger during collisions. However, this is not enough to start.

For this to happen, the droplets must become large and heavy enough that the updrafts of air cannot hold them. One raindrop is obtained by merging with a million other cloud droplets. This is a very lengthy process.

Rain clouds form in the troposphere, the lowest layer of the atmosphere. The troposphere is heating up, so the air temperature near the surface of the planet is very different from the temperature a few kilometers above it - it drops by an average of 6 ° C for each rise. Even in the summer heat, at an altitude of 8-9 km above the Earth's surface, downright arctic cold reigns, and temperatures of -30 ° C are not uncommon here.

Processes inside the cloud

Water vapor, rising up along with air currents, gradually cools down, and then freezes, turning into tiny ice crystals. Thus, in the upper part of the rain cloud there are ice crystals, and in the lower part there are water droplets.

Water vapor condenses inside the cloud. As you know, this process is possible only in the presence of any surface. Water vapor settles on water droplets, all kinds of dust particles and motes raised up by ascending air currents, as well as on ice crystals. The size and weight of the crystals rapidly increases. They can no longer stay in the air and break down.

When passing through the thickness of the cloud, the ice crystals become even larger and more weighty as the condensation continues. If the temperature is above zero at the lower boundary of the cloud, the ice floes melt and fall to the ground in the form of rain; if it is below zero, hail occurs.

And then everything starts all over again. Numerous rain streams form that replenish terrestrial reservoirs. Some of the precipitated moisture seeps through the soil and enters underground water bodies. And part of the water evaporates, and a cloud forms above the earth.