Precipitation

Precipitation is any liquid or solid water droplets that come from the clouds and fall to the ground. It included drizzle, ice crystals, fog, wind, snow pellets, and hail. In this article, we are going to discuss precipitation, and its types, process, and examples.

What is Precipitation?

The formation of a solid from a solution is known as precipitation. Precipitation is any liquid or solid water droplets that come from the clouds and fall to the ground. It included drizzle, ice crystals, fog, wind, snow pellets, and hail. The water vapor condenses and produces tiny water droplets as the air reaches the freezing point, which is also known as the condensation point and dew point.

For example, precipitation occurs when a mass of humid, moist air collides with a mass of cold air. Condensation is when moisture condenses into droplets that become rain or crystals. As these droplets become too large to stay suspended in the air, they fall to the earth as precipitation.

Process of Precipitation

In the atmosphere, moisture occurs as water vapor condenses into larger and larger water droplets. When the drops are too high, they sink to the ground. The water droplets can freeze to form ice if a cloud is colder, as it will be at higher altitudes. Depending on the cloud's temperature and the earth's surface, these ice crystals fall to earth as hail, rain, or snow. Most rain starts as snow high in the sky. When the snowflakes fall into the warm air, they turn into raindrops. Dust or smoke particles in the atmosphere are required for precipitation. These particles, also known as "condensation nuclei", enable a surface for water vapor to condense on. It helps the water droplets to collect and grow large enough to fall to the ground.

Precipitation is still freshwater, particularly though the water comes from the ocean. It's because the salt of the sea does not evaporate with time. However, pollutants in the atmosphere may pollute water droplets until they hit the earth in some cases. The precipitation arising from it is called acid rain. Acid rain doesn't directly affect humans, but it does make lakes and rivers more acidic. As plants and animals also do not adapt to the acidity, it affects aquatic environments.

Examples of precipitation

In the water cycle, precipitation plays a major role as it is the one that allows freshwater to be deposited on the earth. There are various examples of precipitation given as follows:

• Rain
• Hail
• Snow
• Drizzle
• Sleet
• Freezing Rain
• Diamond Dust
• Snow Grains

Rain

Rain would be in the form of liquid droplets. Any of them evaporate when moving through the layer of dry air whenever raindrops fall from high altitude clouds. At times, before hitting the earth, dropping raindrops evaporate. Such rain is known as virga. On the opposite, there is a strong downpour when there is dense cloud cover, and the lower air is moist. The raindrops are large and more frequent in this form of rainfall. The second form of rainfall is usually more regular. Sleet or ice pellets are raindrops that fall from the sky but freeze before reaching the ground.

Hail

Hail appears in the clouds of cold storms. It forms when very cold-water droplets freeze or solidify as they contact dust or soil. Hailstones pelt the upper portion of the cloud as rain pours down. Before it falls, more frozen water droplets are transferred to the hailstone.

Unlike sleet, which forms and freezes when it falls on the earth, it is liquid, and hail falls like a solid ice block. Hailstones are usually small in size, but they may grow up to or larger than 15 cm in diameter and weigh more than a pound.

Snow

It is the type of precipitation that falls in the form of ice crystals. Hail is also frost, but hailstones are only a series of frozen water droplets. The snow has a very complex structure. The ice crystals are formed separately in clouds, and when they fall, they stay together in snowflakes. In comparison to a hail storm, snowfall is normally calm. The hailstones are tough, while the snowflakes are gentle.

Drizzle

Drizzle is a very light rainfall. It's thicker than fog but less than a shower. A mist is a thin fog that condenses near the ground. Fog is formed by ice crystals or cloud water droplets suspended in the air or near the earth's surface. Drizzle droplets are less than 0.5 millimeters (0.02 inches) in diameter. Low stratocumulus clouds form them. They sometimes evaporate before reaching the earth because of their small scale. Drizzle can be persistent in cold ambient temperatures.

Sleet

It is a form of precipitation that consists of a combination of rain and snow. It's a type of frozen rain that forms when rain falls to the ground and passes through a layer of extremely cold air. When violent vertical currents form in the atmosphere, sleet may quickly transform into hailstorms. Sleet is frequently experienced during thunderstorms and is generally followed by frosty ice particles, white deposits, a mixture of semi-solid rain and cloudy snow, and when they strike the ground or any other solid surfaces, ice pellets (sleet) bounce and fall with a harsh hitting sound.

Freezing Rain

Freezing rain occurs when the rain falls below freezing or temperature conditions. Usually, this results in the solidification of the rain droplets. When raindrops move through the atmosphere's sub-freezing layer, they become super-cooled and then freeze when they hit the earth. It is normal to experience an even coating of ice on vehicles, sidewalks, trees, and power lines during freezing rain. The resulting layer of ice is called the glaze, which may build-up to a thickness of a few centimeters. The freezing rains are a significant threat to the regular activity of road transport, aircraft, and power lines.

Diamond Dust

It is a tiny ice crystal generally formed at low temperatures below -30 °C and at low levels. The sparkling effect produced when light reflects off ice crystals in the air gave rise to the name "diamond dust".

Snow Grains

A tiny white or opaque grain of ice is snow grains. The snow grains are fairly smooth and usually less than 1 mm in diameter. They almost equate to the scale of the drizzle.

Types of Precipitation

Three types of precipitation are as follows:

1. Orographic Precipitation
2. Convectional Precipitation
3. Cyclonic or Frontal Precipitation

Orographic Precipitation

This precipitation occurs when the humid and warm air hits an orographic barrier (a mountain range). The atmosphere is pushed to rise due to the initial impetus. As the moisture-laden air increases, condensation forms, and saturation happens rapidly. The excess moisture falls as orographic precipitation down the windward slopes.

Convectional Precipitation

Convectional precipitation happens when the sun's energy heats the earth's surface, allowing water to evaporate and form water vapor. When the earth heats up, the air above it warms up as well. As a consequence, the air expands and rises. This condensation mechanism creates clouds high in the atmosphere.

Cyclonic or Frontal Precipitation

Cyclonic or frontal precipitation happens when the warm and cold air collide. Since warm air is lighter than cold air, it rises above it. The rising air is then cooled to the point of saturation, resulting in heavy rainfall. This type of rain only lasts a few hours. It is noted that tropical cyclones bring a lot of rain.