What are the natural phenomena around us?

1 and graupel

In summer, in mountainous areas, there are often many supercooled water droplets frozen around the crystal nucleus, forming a white, dull round particle. Meteorology calls this kind of thing graupel, and in many places, it is popularly called Mi Xue or Snow Graupel. Generally, the diameter of graupel is between 0.3 and 2.5 mm, which is brittle and easy to break. Polonium does not belong to the category of snow, but it is also a kind of atmospheric solid precipitation.

2. Water

Water is a compound of hydrogen and oxygen, and its chemical formula is H2O. In nature, it exists in three aggregation states: solid, liquid and gas. It is the foundation of all kinds of life on the earth, the most important component of organisms and plays an important role in the evolution of life. The change and movement of water created our world today.

On the earth, water is constantly circulating. The water in the ocean and on the ground is heated and evaporated into the sky. The water vapor moves to other places with the wind. When they encounter cold air, they form precipitation and return to the earth's surface.

3. Ice particles and hail

Ice particles and hail are relatively large translucent ice beads formed by flowing water droplets freezing around condensation nuclei layer by layer. Meteorology, the particle size less than 5 mm is called ice particles, and the particle size greater than 5 mm is called hail. Hail brings great harm to agricultural production. According to records, the largest hail in the world is bigger than a fist, with a diameter of over 1 0cm and a weight of over1kg.

Extended data:

The unnatural phenomena are:

1, red tide

Red tide is the rapid accumulation of algae in estuaries, oceans or fresh water, covering the whole sea area or beach, turning seawater into blood red. This phenomenon is due to the high-density phytoplankton gathering on the water surface to form a dense and visible mass structure. Although some phytoplankton are harmless, some phytoplankton are highly toxic, causing the death of fish, birds and marine mammals.

2. Melting icicles

Melting icicles look very much like ice spears, mainly in alpine glaciers, and their sizes vary from a few centimeters high to 5 meters high.

At first, the sun shines on the surface of snow or alpine glaciers and melts, forming irregular dents. Once dimples like this are formed, the sun's rays will be reflected in the dimples, increasing the sublimation of local substances. With the gradual deepening of micro-depressions, deep grooves are formed, and finally the ice spear structure is formed.

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