How was the calm before the storm formed?

How was the calm before the storm formed?

What was the calm before the storm formed? Quiet before a storm is a very common metaphor. Before the storm comes, there is often a quiet moment, and that moment is the most photographed. Let's see how the calm before the storm is formed.

How is the calm before the storm formed? 1 "Peace before the storm" was very popular in Napoleon's time. Napoleon, a famous general, had a set of fixed procedures in advance before fighting against foreign troops. In the face of fierce fighting, the soldiers are very nervous and afraid. No one wants to talk more, just silently waiting for the battle to come. Therefore, people call it "the peace before the storm".

Of course, this is just a metaphor. "Quiet before a storm" is actually a common weather phenomenon. Our common phenomenon is that there are many storms in summer. When the storm came, the sky was gloomy, there was silence between heaven and earth, and the whole atmosphere was very dull. Soon, the storm began to spread. "Quiet before the storm" still has scientific basis.

Because the ground temperature in the rainstorm area is too high, a strong updraft is formed, so the surrounding air will be sucked away by these airflows. Because the rainstorm trend follows the main wind direction, if the north wind is blowing at that time, the air in the south is being sucked into the rainstorm area by the updraft, and the main airflow (at this time, the north wind) is superimposed with the sucked "south wind" to form a "calm without wind" in a short time.

Others think that "the tranquility before the storm" is an "impression" or "psychological feeling" of people. When water vapor is pushed into the sky at a height of 1000 to 2,000 meters by a strong updraft, a large floating cumulus cloud is formed, and it often takes some time to change from cumulus cloud to cumulonimbus cloud. Compared with the subsequent rainstorm, this period of time was relatively calm, so it gave people the feeling of "the tranquility before the storm".

Now, "quiet before a storm" has changed from a proverb to an idiom to describe the eve of a terrible thing.

How is the calm before the storm formed? 2. Milk cloud.

The appearance of mammatus clouds often indicates changeable stormy weather, although relatively calm weather rarely occurs, or for a long time after the end of bad weather.

The appearance of this cloud is due to the rapid deposition of cold and extremely humid saturated airflow at the top of the storm cloud, which forms a downward expansion or ripple at the bottom of the cloud. There are many changes in the shape of milk clouds, which can be expressed as long wavy ripples covering thousands of square kilometers, or as patch clouds close to spheres.

Perforated cloud

The "hole cloud" is a bright hole-like gap in the middle and high-end clouds, and there are wobbly ice crystal trajectories below. There must be supercooled water droplets in the clouds that form rain holes, and the water in this structure is liquid, even if the temperature in the clouds is below zero degrees Celsius.

When the cloud area begins to freeze, forming a chain reaction, rain clouds appear. In this special process of cloud formation, all the water vapor in supercooled water droplets began to gather to form ice crystals, which gathered quickly and could completely fall from the cloud.

The ice crystals in the fish cave clouds will not fall to the ground, because they are located in the middle and high-end clouds and evaporate and disappear before falling to the ground.

Rolling/rotor cloud

Cirrus clouds are horizontal tubular clouds in downward airflow, and their appearance usually indicates the arrival of storms, and rarely occurs at the end of storms.

This rapidly sinking air mass can attack the land surface, and its powerful airflow can reach a very long distance. Cold air will slide under the hot air layer, and then be sucked up by the vertical updraft of the storm, and then cirrus clouds will condense the water vapor in the hot air to form clouds. Eventually, cirrus will separate from the main clouds of the storm.

It is reported that cirrus clouds often stretch for thousands of meters, and cirrus clouds have appeared on the sea surface of shark bay in Australia. Witnesses said that the scene at that time was spectacular.

"Pink UFO"

In the Jala Mountains of Alp, Alp, a crystallized cumulus cloud once appeared. These cumulus clouds look like pink UFOs because of the sunshine at sunset.

It is reported that cumulus clouds often appear in mountainous areas. People sometimes mistake them for mysterious UFO events.

lenticular cloud

Lenticular clouds are formed in a stable moist air layer, and the moist air is forced to rise to the sky, condensing the water in it to form clouds. If the dry and wet air layers exchange, the cloud will form a vertical structure.

Once it passes through the obstacle, the lenticular cloud will return to its original state, and it will form a standing wave shape in the air, which is located on one side of the mountain range.

Maoziyun

It looks like a hat, usually at the top of a mountain range. When the steady airflow rises beyond the limit, the clouds will cool down and form a strange shape like a hat.

undulatus

Amsterdam Island in the South Indian Ocean is one of the most remote islands on the earth, but a strange cloud-"wave cloud" often appears over the island.

It can form a microwave-like cloud, separating the Antarctic from the Indo-Australian continental plate. Although the island is only 88 1 m high, it can affect the distribution of low clouds over the South Indian Ocean. A layer of moist air rises and falls on the island, forming a narrow and continuous lenticular cloud, just like the remnants of atmospheric waves.

When this cloud structure extends down to the island, it is like a ripple left by a ship crossing the water surface, extending for hundreds of kilometers, and finally mixing with the cumulus edge in the north.

nimbus

This kind of cloud looks very much like jellyfish floating in the air, and their tentacles hang just below them, much like a "rain flag". Usually it rains or snows in this state, but raindrops or snowflakes have evaporated and disappeared before falling to the ground.

Langhuayun

This kind of cloud looks like a huge wave on the shore. Very rare, it will only disappear 1-2 minutes. It is reported that the formation of this cloud is caused by wind shear.

This cloud is formed by a cold air current at the lower part and a warm air current at the upper part. The upper airflow moves faster than the lower airflow, and the wind shear will make the clouds fluctuate. If the wind speed is appropriate, the fluctuation of the upper airflow will be faster than that of the lower airflow, thus forming a spray like a coast.

Horseshoe vortex cloud

Horseshoe vortex clouds are very rare and usually disappear only for 1-2 minutes. It is usually formed in horizontal rotating airflow, also known as air vortex.

This kind of airflow movement is usually formed by updraft, which will suddenly change when the airflow is horizontal and windy, thus causing the airflow to vortex. When the airflow at the curved end of the vortex cools down, a new rotating dentate cloud can be formed.

The most suitable observation of horseshoe vortex cloud is near supercell storm, which refers to lightning storm accompanied by rotating updraft. Wind accelerates the formation of storms and promotes the shear of airflow to some extent.