Snow, ice, drizzle, hail and rain are precipitation. They should be distinguished from hoarfrost and dew, which is nothing but condensed moisture,
Settled on objects or plants. A phenomenon like fog also comes from temperature differences. For example, in the fall,
water evaporates from warmer bodies of water. Steam entering cold air immediately condenses. But the water suspension, due to its own gravity, cannot rise up and become a cloud, therefore it spreads near the ground itself, filling the lowlands and floodplains of the rivers. However, here we will focus on precipitation. What is the difference between hail and similar grains and
icy rain? Learn from this article.
Transitional state?
Even a primary school student will say what the city is: something in between rain and snow. Water droplets harden and turn into ice - small and large. When they fall to the ground, they make a loud noise, as if nuts or pebbles are pouring in. The hailstones do not melt right away. Sometimes you can watch how they cover the earth with a carpet several tens of centimeters high. But the icy rain, although it painfully cuts his face, immediately turns into water. Sometimes a crystal ringing of individual "drops" on the asphalt is heard. But more often this type of precipitation is accompanied by the sounds of ordinary rain. And snow pellets pouring to the ground with a quiet rustle. These precipitations are different in appearance. Hailstones are large and translucent. Freezing rain is like shards of glass. And grains can be likened to miniature snowballs.
How is snow formed?
To seriously understand the question of what hail is, it is simply necessary to return to the basics of natural history and remember how clouds are formed that carry rain or snow. Moisture evaporates from the surface of the earth. But most often clouds form over oceans, where there is more water.
The ascending air
flows lift this steam up. At different heights, moisture condenses due to lower air temperatures. But it does not turn into droplets of water, but is converted into ice crystals, bypassing the liquid state. If the cloud is small and light, the wind drives it to drier areas, where it melts, without giving the earth rainfall. A dense
atmosphere cannot hold heavy, low-floating clouds. Ice crystals begin to sink. If the air temperature at the surface of the earth is positive, they melt, turning into droplets of rain. Well, if outside the window - below zero, the crystals grow together with each other, forming snowflakes of various shapes and sizes.
What is hail?
This is a completely different type of rainfall. And he arises in completely different clouds. Maybe you remember which clouds threaten us with a shower? Dense, dark gray, sometimes even purple ... Tall, like swirling towers, they fly swiftly, like a tornado. Unlike heavy rain, hail is rarely accompanied by lightning and thunder. But there is always a gale of wind. A hailstone is born in the same way as a snowflake - from an ice crystal. But it is not formed at all in the flat clouds that carry snow. Hail generates the form of clouds. High bulk rises several kilometers. It is clear that there is a temperature difference between the lower and upper edges of such a cloud. Crystals located closer to the ground melt, turning into drops of water (hail never falls in winter). But instead of pouring rain, powerful updrafts push this moisture up where it freezes — this time in the form of a small ice ball. If the movement of the wind inside the cloud is weak, a small hail falls. But if the air flow is strong, then the thawing ball was again brought up, where it is surrounded by another icy shell. Sometimes the gradients, when encountered, merge with each other. Then their shape changes. This is no longer a ball, but a complex conical or pyramidal formation. The more a drop makes migrations, the larger the hail. The maximum size of the ice pieces was 150 mm, and the weight was more than a kilogram.
How to prevent hail
It is clear that falling to the ground at a speed of 150 kilometers per hour, not so huge specimens can cause serious injuries and damage. People have long been thinking how to prevent the death of crops and livestock from hail. In the Middle Ages, they discovered a pattern: if you make very loud and sharp sounds, then rain will pour out of the cloud. Therefore, when approaching danger, people beat a bell or shot a cannon. From the pulsation of the air, the gradients disintegrated, became smaller and melted before they reached the ground. Now they are shooting at a dangerous cloud with a special projectile with silver or lead iodide reagent.
Now that we have learned what hail is, let's figure out what snow pellets are. These are small, 1-2 mm diameter snow balls. Unlike hail, they are fragile, opaque, white. In fact, these are fused and compacted snowflakes.
For general development
In modern Russian, the word "hail" has another meaning. This is the name of the multiple launch rocket system, which replaced the obsolete Katyusha. This deadly weapon was developed by A. I. Ganichev and the design bureau of the State Scientific-Production Enterprise “Fusion”. The base complex is modified from year to year, giving rise to Grad-V, P, 1A and other installations.