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DesInventar Open Source Initiative

Definition of disaster types

Please find below the definition of disasters type used by our methodology.

Our methodology and our office are part of the Disaster Loss Data (DATA) project, under the umbrella of the Integrated Research on Disaster Risk (IRDR) programme and will apply the common standardized classification and definition after their approvals.

Disaster Loss Data (DATA) family classification

Airburst Extraterrestrial
An explosion of a comet or meteoroid within the Earth’s atmosphere without striking the ground.

Animal Incident Biological
Human encounters with dangerous or exotic animals in both urban and rural environments.

Ash Fall Geological
Fine (less than 4 mm in diameter) unconsolidated volcanic debris blown into the atmosphere during an eruption; can remain airborne for long periods of time and travel considerable distance from the source.

Avalanche  Hydrological
A large mass of loosened earth material, snow, or ice that slides, flows or falls rapidly down a mountainside under the force of gravity.
• Snow Avalanche: Rapid downslope movement of a mix of snow and ice.
• Debris Avalanche: The sudden and very rapid downslope movement of unsorted mass of rock and soil. There are two general types of debris avalanches - a cold debris avalanche usually results from an unstable slope suddenly collapsing whereas a hot debris avalanche results from volcanic activity leading to slope instability and collapse.

Bacterial Disease Biological
An unusual increase in the number of incidents caused by the exposure to bacteria either through skin contact, ingestion or inhalation. Examples include salmonella, MSRA, and cholera, among others.

Biological Hazard Biological
A hazard caused by the exposure to living organisms and their toxic substances (e.g. venom, mold) or vector-borne diseases that they may carry. Examples are venomous wildlife and insects, poisonous plants, and mosquitoes carrying disease-causing agents such as parasites, bacteria, or viruses (e.g. malaria).

Climatological Hazard Climatological
A hazard caused by long-lived, meso- to macro-scale atmospheric processes ranging from intra-seasonal to multi-decadal climate variability.

Coastal Erosion  Hydrological
The temporary or permanent loss of sediments or landmass in coastal margins due to the action of waves, winds, tides, or anthropogenic activities.

Coastal Flood  Hydrological
Higher-than-normal water levels along the coast caused by tidal changes or thunderstorms that result in flooding, which can last from days to weeks.

Cold Wave  Meteorological
A period of abnormally cold weather. Typically a cold wave lasts two or more days and may be aggravated by high winds. The exact temperature criteria for what constitutes a cold wave vary by location.

Convective Storm  Meteorological
A type of meteorological hazard generated by the heating of air and the availability of moist and unstable air masses. Convective storms range from localised thunderstorms (with heavy rain and/or hail, lightning, high winds, tornadoes) to meso-scale, multi-day events.

Debris Flow, Mud Flow, Rock Fall  Hydrological
Types of landslides that occur when heavy rain or rapid snow/ice melt send large amounts of vegetation, mud, or rock downslope by gravitational forces.

Derecho  Meteorological
Widespread and usually fast-moving windstorms associated with convection/convective storm. Derechos include downburst and straight-line winds. The damage from derechos is often confused with the damage from tornadoes.

Disease  Biological
Either an unusual, often sudden, increase in the number of incidents of an infectious disease that already existed in the region (e.g., flu, E. coli) or the appearance of an infectious disease previously absent from the region (e.g., plague, polio).

Drought  Climatological
An extended period of unusually low precipitation that produces a shortage of water for people, animals and plants. Drought is different from most other hazards in that it develops slowly, sometimes even over years, and its onset is generally difficult to detect. Drought is not solely a physical phenomenon because its impacts can be exacerbated by human activities and water supply demands. Drought is therefore often defined both conceptually and operationally. Operational definitions of drought, meaning the degree of precipitation reduction that constitutes a drought, vary by locality, climate and environmental sector.

Earthquake  Geological
Sudden movement of a block of the Earth’s crust along a geological fault and associated ground shaking.

Energetic Particles Extraterrestrial
Emissions from solar radiation storms consisting of pieces of matter (e.g., protons and other charged particles) moving at very high speed. The magnetosphere and atmosphere block (solar) energetic particles (SEP) from reaching humans on Earth but they are damaging to the electronics of space-borne technology (such as satellites) and pose a radiation hazard to life in space and aircrafts travelling at high altitudes.

Expansive Soil  Hydrological
Earthen material, particularly clays that, upon wetting, freezing, or drying will alternately expand or contract causing damage to foundations of buildings and other structures. Shrinkage is generally referred to as desiccation.

Extraterrestrial Hazard Extraterrestrial
A hazard caused by asteroids, meteoroids, and comets as they pass near-earth, enter the Earth’s atmosphere, and/or strike the Earth, and by changes in interplanetary conditions that effect the Earth’s magnetosphere, ionosphere, and thermosphere.

Extratropical Storm  Meteorological
A type of low-pressure cyclonic system in the middle and high latitudes (also called mid-latitude cyclone) that primarily gets its energy from the horizontal temperature contrasts (fronts) in the atmosphere. When associated with cold fronts, extratropical cyclones may be particularly damaging (e.g., European winter/windstorm, Nor’easter).

Extreme Temperature  Meteorological
A general term for temperature variations above (extreme heat) or below (extreme cold) normal conditions.

Fire following Earthquake Geological
Urban fires triggered by earthquakes. Particularly susceptible areas include densely spaced, wooden buildings that dominate local architecture, and where the earthquake has damaged or ruptured water and gas pipelines. Small local fires have the potential to merge into conflagrations destroying many city blocks.

Flash Flood  Hydrological
Heavy or excessive rainfall in a short period of time that produce immediate runoff, creating flooding conditions within minutes or a few hours during or after the rainfall.

Flood  Hydrological
A general term for the overflow of water from a stream channel onto normally dry land in the floodplain (riverine flooding), higher-thannormal levels along the coast and in lakes or reservoirs (coastal flooding) as well as ponding of water at or near the point where the rain fell (flash floods).

Fog  Meteorological
Water droplets that are suspended in the air near the Earth’s surface. Fog is simply a cloud that is in contact with the ground.

Forest Fire  Climatological
A type of wildfire in a wooded area.

Frost, Freeze  Meteorological
Frost is the consequence of radiative cooling resulting in the formation of thin ice crystals on the ground or other surfaces in the form of needles, feathers, scales, or fans. Frost occurs when the temperature of surfaces is below freezing and water vapor from humid air forms solid deposits on the cold surface. Freeze occurs when the air temperature is at (32˚F/0˚C) or below over a widespread area for a climatologically significant period of time. Use of the term is usually restricted to advective situations or to occasions when wind or other conditions prevent frost. Frost and freeze are particularly damaging during the crop growing season.

Fungal Disease  Biological
Exposure to fungi either through skin contact, ingestion or inhalation of spores resulting in an unusual increase in the number of incidents. Examples are fungal pneumonia, fungal meningitis, etc.

Geomagnetic Storm Extraterrestrial
A type of extraterrestrial hazard caused by solar wind shockwaves that temporarily disturb the Earth’s magnetosphere. Geomagnetic storms can disrupt power grids, spacecraft operations, and satellite communications.

Geophysical Hazard  Geological
A hazard originating from solid earth. This term is used interchangeably with the term geological hazard.

Glacial Lake Outburst Climatological
A flood that occurs when water dammed by a glacier or moraine is suddenly released. Glacial lakes can be at the front of the glacier (marginal lake) or below the ice sheet (sub-glacial lake).

Ground Movement Geological
Surface displacement of earthen materials due to ground shaking triggered by earthquakes or volcanic eruptions.

Hail  Meteorological
Solid precipitation in the form of irregular pellets or balls of ice more than 5 mm in diameter.

Heat Wave  Meteorological
A period of abnormally hot and/or unusually humid weather. Typically a heat wave lasts two or more days. The exact temperature criteria for what constitutes a heat wave vary by location. Hydrological Hazard A hazard caused by the occurrence, movement, and distribution of surface and subsurface freshwater and saltwater.

Ice Jam Flood  Hydrological
The accumulation of floating ice restricting or blocking a river’s flow and drainage. Ice jams tend to develop near river bends and obstructions (e.g., bridges).

Impact - Collision Extraterrestrial
A type of extraterrestrial hazard caused by the collision of the Earth with a meteoroid, asteroid or comet.

Insect Infestation Biological
The pervasive influx, swarming and/or hatching of insects affecting humans, animals, crops, and perishable goods. Examples are locusts and African Bees.

Lahar  Geological
Hot or cold mixture of earthen material flowing on the slope of a volcano either during or between volcanic eruptions.

Landslide following Earthquake Geological
Independent of the presence of water, mass movement may also be triggered by earthquakes.

Lava Flow  Geological
The ejected magma that moves as a liquid mass downslope from a volcano during an eruption.

Lightning  Meteorological
A high-voltage, visible electrical discharge produced by a thunderstorm and followed by the sound of thunder.

Liquefaction  Geological
The transformation of (partially) water-saturated soil from a solid state to a liquid state caused by an earthquake. Liquefaction reduces the strength and stiffness of soil causing buildings to topple over.

Mass Movement  Geological
Any type of downslope movement of earth materials.

Meteorological Hazard  Meteorological
A hazard caused by short-lived, micro- to meso-scale extreme weather and atmospheric conditions that last from minutes to days.

Parasitic Disease Biological
Exposure to a parasite–an organism living on or in a host–causes an unusual increase in the number of incidents. Exposure to parasites occurs mostly through contaminated water, food or contact with insects, animals (zoonotic), pets, etc. Examples are malaria, chagas disease, giardiasis and trichinellosis.

Prion Disease  Biological
A type of biological hazard caused by prion proteins. Prion diseases or transmissible spongiform encephalopathies (TSEs) are a family of rare progressive neurodegenerative disorders that affect both humans and animals characterised by long incubation periods and neural loss. Examples are Bovine Spongiform Encephalophathy (BSE), Creutzfeldt- Jakob-Disease (CJD), Kuru, etc.

Pyroclastic Flow Geological
Extremely hot gases, ash, and other materials of more than 1,000 degrees Celsius that rapidly flow down the flank of a volcano (more than 700 km/h) during an eruption.

Radio Disturbance Extraterrestrial
Triggered by x-ray emissions from the Sun hitting the Earth’s atmosphere and causing disturbances in the ionosphere such as jamming of high and/or low frequency radio signals. This affects satellite radio communication and Global Positioning Systems (GPS).

Rain  Meteorological
Water vapour condenses in the atmosphere to form water droplets that fall to the Earth.

Riverine Flood  Hydrological
A type of flooding resulting from the overflow of water from a stream or river channel onto normally dry land in the floodplain adjacent to the channel.

Rogue Wave  Hydrological
An unusual single crest of an ocean wave far out at sea that is much higher and/or steeper than other waves in the prevailing swell system.

Sandstorm, Dust Storm  Meteorological
Strong winds carry particles of sand aloft, but generally confined to less than 50 feet (15 m), especially common in arid and semi-arid environments. A dust storm is also characterised by strong winds but carries smaller particles of dust rather than sand over an extensive area.

Seiche  Hydrological
A standing wave of water in a large semi- or fully-enclosed body of water (lakes or bays) created by strong winds and/or a large barometric pressure gradient,

Shockwave  Extraterrestrial
A shockwave carries energy from a disturbance through a medium (solid, liquid, gas) similar to a wave though it travels at much higher speed. It can be a type of extraterrestrial hazard caused by the explosion (airburst) or impact of meteorites that generate energy shockwaves capable of shattering glass, collapsing walls, etc.

Sinkhole  Hydrological
Collapse of the land surface due to the dissolving of the subsurface rocks such as limestone or carbonate rock by water.

Snow, Ice  Meteorological
Precipitation in the form of ice crystals/snowflakes or ice pellets (sleet) formed directly from freezing water vapour in the air. Ice accumulates when rain hits the cold surface and freezes.

Space Weather  Extraterrestrial
A general term for extraterrestrial weather conditions driven by solar eruptions such as geomagnetic storms, radio disturbances, and solar energetic particles.

Storm Surge  Meteorological
An abnormal rise in sea level generated by a tropical cyclone or other intense storms.

Subsidence  Climatological
Subsidence refers to the sinking of the ground due to groundwater removal, mining, dissolution of limestone (e.g., karst, sinkholes), extraction of natural gas, and earthquakes.

Tornado  Meteorological
A violently rotating column of air that reaches the ground or open water (waterspout).

Tropical Cyclone  Meteorological
A tropical cyclone originates over tropical or subtropical waters. It is characterised by a warm-core, non-frontal synoptic-scale cyclone with a low pressure centre, spiral rain bands and strong winds. Depending on their location, tropical cyclones are referred to as hurricanes (Atlantic, Northeast Pacific), typhoons (Northwest Pacific), or cyclones (South Pacific and Indian Ocean).

Tsunami  Geological
A series of waves (with long wavelengths when traveling across the deep ocean) that are generated by a displacement of massive amounts of water through underwater earthquakes, volcanic eruptions or landslides. Tsunami waves travel at very high speed across the ocean but as they begin to reach shallow water they slow down and the wave grows steeper.

Viral Disease  Biological

Volcanic Activity  Geological
A type of volcanic event near an opening/vent in the Earth’s surface including volcanic eruptions of lava, ash, hot vapour, gas, and pyroclastic material.

Wave Action  Hydrological
Wind-generated surface waves that can occur on the surface of any open body of water such as oceans, rivers and lakes, etc. The size of the wave depends on the strength of the wind and the traveled distance (fetch).

Wildfire  Climatological
Any uncontrolled and non-prescribed combustion or burning of plants in a natural setting such as a forest, grassland, brush land or tundra, which consumes the natural fuels and spreads based on environmental conditions (e.g., wind, topography). Wildfires can be triggered by lightning or human actions.

Wind  Meteorological
Differences in air pressure resulting in the horizontal motion of air. The greater the difference in pressure, the stronger the wind. Wind moves from high pressure toward low pressure.

Winter Storm, Blizzard  Meteorological
A low pressure system in winter months with significant accumulations of snow, freezing rain, sleet or ice. A blizzard is a severe snow storm with winds exceeding 35 mph (56 km/h) for three or more hours, producing reduced visibility (less than .25 mile (400 m).

DesInventar specific definition
Please noted, that the methodology allows to add, remove, create any terms related to specific disasters, however, we recomend to map them to the international standardized definition.
Find below, other hazards available with our methodology.

Automobile, rail, aircraft or navigation accidents. Limited to accidents induced by natural phenomena, such as landslides, earthquakes, hurricanes, rain, etc. Includes transportation accidents generating spills or leaks of harmful substances, regardless of the cause.

Torrential water flows dragging large amounts of solid material (pebbles, stones, and rock blocks) common in dry regions river beds which are produced by heavy rain. Equivalent to the term “huaico” used in Peru.

Boat Capsize
Overturning of a boat due to hitting the water-bed or due to sea disturbances, or other natural phenomena such as heavy winds or flash floods.

Explosions of any type, but limited to those induced or highly connected to natural phenomena, such as electrical storms, earthquakes, droughts, etc.

Extreme Rain
Precipitation. Includes punctual, persistent or torrential rain, or rain exceeding the rainfall averages of a specific region; also, unusual long rain periods. Rain includes terms such as downpour, cloudburst, heavy shower, deluge, etc.

Urban, industrial or rural fires, but not including forest fires. Limited to those induced or highly connected to natural phenomena, such as electrical storms, earthquakes, droughts, etc.

Flood - Urban Flood
Storm water that gets collected in city or urban areas after heavy rains due to blocking or under capacity of storm water drains. It may also be a riverine flood occurring specifically over an urban area.

Leak/Oil Spill
Leak of harmful liquid, solid or gas substances, whether radioactive or not, generated by technological accidents, human fault or transportation accidents.

Soil liquefaction describes a phenomenon whereby a saturated soil substantially loses strength and stiffness in response to an applied stress, usually earthquake shaking or other sudden change in stress condition, causing it to behave like a liquid.

Panic o mass hysteria among people concentrated in a certain place (stadiums, theaters, etc.) that can kill or injure them, and cause physical damage. Limited to those induced or highly connected to natural phenomena, such as electrical storms, earthquakes, etc., and early warnings about incoming events.

Pollution Concentration of
polluting substances in the air, water or soils, at levels harmful to human health, crops or animal species.

Deposits of solid material on hillsides and river beds produced by mass movements, wind, floods or surface erosion with damages on crops, utilities or other infrastructure.

Soil Erosion
Washing away of soil down the surface of hill slopes or mass movements due to storm water flow during intense rains or winds. This can cause in turn sedimentation in streams / rivers and areas at the toe of the hills.

Structural Collapse
Damages or collapse of any type of structure for reasons such as excess weight in public places, bridges, etc. This event includes damage that, although not taking the structures to the point of collapse, does make them unusable. Damages in structures caused by natural phenomena are reported as an effect of these phenomena.


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