The Flood is a natural phenomenon caused by the excess of water in the landscape outside the watercourse. Its consequences can be various damage to property, environmental damage or sacrifice in human life. Floods cause damage particularly to households, infrastructure and businesses located in natural floodplains.
Some floods develop slowly, while others like flash floods can develop in just a few minutes and without visible signs of rain. In addition, floods can be local, impacting a neighborhood or community, or very large, affecting entire river basins.
We distinguish two terms. Flood – Significant transient increase in water flow, either due to sudden increase in flow (eg as a result of precipitation and / or snow melting), or by a reduction in the flow of the channel (ice congestion, clogging of bridge holes, etc.). Flash Flood – Spilling water from the riverbed as a result of the flood.
is a heavily rotating vortex that occurs below the bottom of a convective storm that during its existence reaches at least one earth surface and is strong enough to cause material damage to it. It is capable of bringing objects up to 5 tons into the air. The wind speed in tornadoes ranges from 50 to 100 m / s or more, with an average of eight meters.
Tornadoes occur in storms almost all over the world, with the most famous area being the US Midwest and South, it is a so-called tornado alley, respectively. a tornado belt that stretches in the Mississippi River Basin between the Rocky Mountains and the Apala Mountains – Texas, Kansas, Oklahoma and Nebraska. In the United States, the largest occurrence of tornadoes in the world. Most tornadoes occur there between April and June.
There are two types of tornadoes. The first type is the so-called super-electric tornado, which is linked to the occurrence of super-storm storm. Supercele is a convective cloud made up of a single massive storm cell. It rotates heavily around its vertical axis and can see a so-called mesocyclone with a diameter of about 20 km. Such a storm is one of the most deadly convective storm ever.
The second type is the so-called non-supermarket tornado, whose maternal storm is not superceleral. This means that it is a storm of more storm cells. The non-suppressor storm cell has a lifetime of about 30 minutes, which does not mean that the storm lasts so long. The storm cells of the storm are at different stages of development and new ones are emerging. Tornadoes bound to this storm are much weaker, but it is not excluded that there will be a strong tornado. This type of tornado is typical for the Czech Republic, where the occurrence of supercelence is rare.
The Earthquake is the sudden movement of the earth’s crust, caused by the release of tension – for example, from the constant movements of the earth plates – along the breaks. Greater earthquakes are usually found in those areas of the world through which major breakthroughs pass (the west coast of America, East Asia and the islands between it and Australia, the Caucasus, Turkey and Iran, the Mediterranean, etc.) Earthquake study deals with geophysics specifically with its part of seismology.
The epicenter is the point at ground level directly above the hypocenter.
A Storm is a disturbed state of an environment or an astronomical body’s atmosphere particularly affecting its surface, and strongly implying severe weather. It may be marked by significant disturbances to normal conditions such as strong winds, tornados, hail, thunder and lightning, heavy rainfall, heavy winds (tropical cyclone, windstorm), or wind transporting some substance through the atmosphere as in a dust storm, blizzard, sandstorm, etc.
A winter storm is an event in which varieties of precipitation are formed that only occur at low temperatures, such as snow or sleet, or a rainstorm where ground temperatures are low enough to allow ice to form (i.e. freezing rain). In temperate continental climates, these storms are not necessarily restricted to the winter season, but may occur in the late autumn and early spring as well.
In some cases, it may occur on the surface of the surface that the water in the liquid phase, which after the extinction on the object immediately freezes, allows the formation of ice crusts on the objects. In this case, we are talking about glaciers.
During the snowstorm there will be a lot of snow on the earth’s surface that will cause subsequent calamity situations in areas such as traffic collapse, power line breaks, or crossings in forests. It is reported that about 2 cm of water is able to transfer up to 20 cm of snow cover.
A very strong and violent snow storm that passes through the gale is called a blizzard.
An avalanche (also called a snowslide) is a rapid flow of snow down a sloping surface. Avalanches are typically triggered in a starting zone from a mechanical failure in the snowpack (slab avalanche) when the forces on the snow exceed its strength but sometimes only with gradual widening (loose snow avalanche). After initiation, avalanches usually accelerate rapidly and grow in mass and volume as they entrain more snow. If the avalanche moves fast enough, some of the snow may mix with the air forming a powder snow avalanche, which is a type of gravity current.
Slides of rocks or debris, behaving in a similar way to snow, are also referred to as avalanches.
In mountainous terrain, avalanches are among the most serious objective natural hazards to life and property, with their destructive capability resulting from their potential to carry enormous masses of snow at high speeds.
A Conflagration is a large and destructive fire that threatens human life, animal life, health, and/or property. It may also be described as a blaze or simply a (large) fire.
A Conflagration can begin accidentally, be naturally caused (wildfire), or intentionally created (arson).
Landslides occur when the slope changes from a stable to an unstable condition. A change in the stability of a slope can be caused by a number of factors, acting together or alone. Natural causes of landslides include:
Gravitational slope movements: A group of slope movements that are the origin of gravity. Tensions in the slope affect the development of slope (altitude or slope change), its relief and subsurface water regime. Gravitational forces subsequently cause shear stress on the slopes, causing deformation of rock or earth. Depending on the speed, the gravitational slope moves (from the slowest to the fastest). It’s Longevity, Slope, and Leadership.
Fluvial slope movements: A group of slope motions with water. In the case of surface water runoff, whether precipitation or melting (ie caused by melting), the rhone is mentioned. There is unconcentrated water flowing on the surface of the terrain, which takes away the fine particles of soil or the weathered shell. Rain or hot water that is infiltrated into the soil, the slope continues to act mechanically and chemically. Subsurface water can then cause the following uphill movements. These are Sufozi, Soliflukci and Drowning.
A Mudslide, is a catastrophically rapid slope stream of flowing material, consisting of fine-grained material saturated with water, with debris up to blocks of rocky rocks. The speed of such a current ranges from a km / h to more than 100 km / h. The cause of the formation of the mary is the saturation of the slope with water, which can be caused by intense rainfall or melting snow cover. As a condition of the formation of the mure there is sufficient incline of the slope and sufficient layer of sediments on the slope.
A Pyroclastic Cloud, also referred to as a hot cloud, is often the occurrence of explosive volcanic eruptions. It is a moving, fluidized mixture of gaseous volcanic gases, magma and volcanic ash fragments, with a temperature of 100 to 1100 ° C, moving (like avalanche) along the volcanic slope down at high speeds (150-700 km / h). These properties are one of the most devastating forms of volcanic activity. Pyroclastic Cloud occur in explosive eruptions of viscous magma.
The causes of pyroclastic Cloud are as follows: Collapse of the cloud of gases and ash. If the explosion pressure is not sufficient to push ash clouds high into the atmosphere, the dropped material falls and flows down the slopes of the volcano. Collapse of the volcanic dome and its subsequent decay. Destruction of a part of the volcano during a major explosion. “Foaming” of the lava during the process of its degassing during an eruption.