which direct water to flow downhill to form rivers and lakes.
•
Erosional processes, including flooding, landslides, and windstorms replenishes soil and helps
sustain life.
Floods don't distribute often large area but extending more discrete form. All
of these make
difficult to observe floods and their maximum, as a result it is possible only after floods to determine the
maximum water flow according to their traces. The formation of rainfall floods is different from the
formation flood flow. At that time the main role is duration and character of rainfalls. Firstly determined
the rainfall area, its duration, quantity, average and maximum intensity and then on the
basis of these
determined the scale of the floods. Depending on all of them rainfall flood is the most dangerous for
forming flooding in river.
Results
Research of floods and droughts event from a scientific point are very important for their early
warning and prevention of damage. That time this is an important challenge for world scientists. The
past 20 years exposed to flood at the banks of the lake and largest river and suffered damage from this
incident cases was significantly increased. This is very seriously problem for the farms of in the area and
people which living here.
Flooding can cause a range
of health impacts and risks, including: death and injury, contaminated
drinking water, hazardous material spills, increased populations of disease-carrying insects and rodents,
moldy houses, and community disruption and displacement.
As rains become heavier, streams, rivers, and lakes
can overflow, increasing the risk of water-
borne pathogens flowing into drinking water sources. Downpours can also damage critical infrastructure
like sewer and solid waste systems, triggering sewage overflows that can spread into local waters.
In addition to extreme floods, other dangerous geographical events for agriculture is drought.
Drought is an insidious hazard of nature. It is often referred to as a "creeping phenomenon" and its
impacts vary from region to region. Drought can therefore be difficult for people to understand.
Heavy rains also make some difficulty for aviation activities, even can be caused aviation
disasters. Incessant rainfall weakens the appearance, causing the electricity and icing of aircraft during
the flight. Torrential rains significantly affects landing of the aircraft.
Lightning is the most dangerous atmospheric events for economy. Especially it has a serious
impact for transport. At aeronavigation lightning was caused very serious losses and many human
deaths.
Lightning is a sudden electrostatic discharge during an electrical
storm between electrically
charged regions of a cloud , between that cloud and another cloud (CC lightning), or between a cloud
and the ground (CG lightning). As a rule lightning occurs on ball-rain (CC) clouds and it is accompanied
with downpour and hard rain.
At Earth's surface at the same time nearly 1,500 lightning are observed. Their average speeds are
registered for 46/1 second. Lightning are unevenly distributed on the surface of our planet. There are
ten times more lightning over the ocean than on the mainland. The maximum lightning activity on Earth
is observed in Central Africa. Over the Arctic and Antarctic polar regions are
almost never observed the
lightning .
Watch closely and you will see the step leaders heading down from the cloud. These are rarely
visible and last only a few thousandths of a second. Note that one reaches the ground and this is the
path that the much brighter lightning bolt follows.
The intensity of the lightning depends on the sun's rays, therefore the maximum of the afternoon
hours in the summer, but the minimum is taken into account at the time of the sinking sun.
Discussion
This paper addresses natural disasters whose origin and scale are not limited to natural causes, in
other words where the causes and the effects are also closely related to demographic and industrial
growth, something inherent to the socio-economic growth of contemporary societies.
The natural hazards are - related to the activities of the wind - strong winds, wind shear, wind side,
crosswind, which caused to limited
visibility distance - blizzard, fog, dust and dust storms, heavy rains
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and low clouds, related to convective processes - lightning, turbulence, extreme temperatures and
besides hail.
Likewise, the analysing of dangerous atmospheric events is very important for agrometeorology
which is the main field of the country's economy. Particularly, hail, extreme temperatures and shower is
very important for agriculture and livestock. These events have a very negative impact on agricultural
economy.
The dangerous meteorological events affect transport system, especially aviation transport.
Nowadays, many traffic accidents have occurred because of limited visibility distance. According to flight
experience, 60% of aircraft accidents due to limitation of meteorological visibility occurred by fog effect.
In recent years, it was clear by the
world flight experience, 78% of aviation events happened by
metereological conditions during take-off and landing of aircraft is caused by wind drifts.
Global statistics on the economic impact of disasters are collected and reported as a total sum for
all sectors, and do not capture the impact on individual sectors. National and international disaster loss
databases typically report populations affected and damage to housing and other infrastructure, but
seldom report damage or losses in the agriculture sector. As a result, there is no clear understanding of
the extent to which natural hazards and disasters impact the agriculture sector and subsectors in
developing countries.
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