Natural disasters such as floods, hurricanes, tornadoes, volcanic eruptions, earthquakes and tsunamis are major adverse events caused by natural processes that can result in loss of life, property damage or economic impacts depending on the resilience of the affected population. While an event may not cause widespread damage in an unpopulated area, the same event can have disastrous consequences if it occurs in a vulnerable area, as seen with the 2015 Nepal earthquake that caused lasting damage requiring years of repairs. Earthquakes are caused by the sudden release of energy in the Earth's crust that creates seismic waves, which can be powerful enough to destroy cities. Floods occur when water submerges land that is usually dry, such as from overflowing

2. A natural disaster is a major adverse event resulting
from natural processes of the Earth; examples
include floods, hurricanes, tornadoes, volcanic
eruptions, earthquakes, tsunamis, and other geologic
processes. A natural disaster can cause loss of life or property
damage, and typically leaves some economic damage in its
wake, the severity of which depends on the affected
population's resilience, or ability to recover and also on the
infrastructure available.
An adverse event will not rise to the level of a disaster if it
occurs in an area without vulnerable population. In a vulnerable
area, however, such as Nepal during the 2015 earthquake, an
earthquake can have disastrous consequences and leave lasting
damage, requiring years to repair.

3. An earthquake (also known as
a quake, tremor or temblor) is the shaking
of the surface of the Earth, resulting from
the sudden release of energy in
the Earth's crust that creates seismic
waves. Earthquakes can be violent enough
to toss people around and destroy whole
cities. The seismicity or seismic activity of
an area refers to the frequency, type and
size of earthquakes experienced over a
period of time.

4. A flood is an overflow of water that submerges
land which is usually dry.[1] The European
Union (EU) Floods Directive defines a flood as a
covering by water of land not normally covered
by water.[2] In the sense of "flowing water", the
word may also be applied to the inflow of
the tide.
Flooding may occur as an overflow of water
from water bodies, such as a river, lake, or
ocean, in which the water overtops or
breaks levees, resulting in some of that water
escaping its usual boundaries,[3] or it may occur
due to an accumulation of rainwater on
saturated ground in an areal flood.

5. A volcano is a mountain that opens downward
to a pool of molten rock below the surface of
the earth. When pressure builds up, eruptions
occur. Gases and rock shoot up through the
opening and spill over or fill the air with lava
fragments. Eruptions can cause lateral blasts,
lava flows, hot ash flows, mudslides,
avalanches, falling ash and floods. Volcano
eruptions have been known to knock down
entire forests. An erupting volcano can trigger
tsunamis, flash floods, earthquakes, mudflows
and rockfalls.