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List Of Severe Weather Phenomena
Severe weather phenomena are weather conditions that are hazardous to human life and property. Severe weather can occur under a variety of situations, but three characteristics are generally needed: a temperature or moisture boundary, moisture, and (in the event of severe, precipitation-based events) instability in the atmosphere. Examples Atmospheric * Fog ** Haar (fog) ** Ice fog Electrical storms * Storms * Thunderstorms ** Multicellular thunderstorm ** Pulse storm ** Squall line ** Storm cell (single-cell) ** Supercells, rotating thunderstorms Fire * Wildfire or bushfire (ignition of wildfires is sometimes by lightning strike, especially in "dry thunderstorms") ** Firestorm ** Fire whirl, also called ''firenado'' and ''fire tornado'' Flooding * Floods ** Flash floods ** Coastal flooding ** Tidal flooding Oceans and bodies of water * Harmful algal bloom ** Blue green algae ** Red tide * High seas * High tides * king tide * Ice shove * Rogue wave * Seiche * Swell (ocea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weather
Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloud cover, cloudy. On Earth, most weather phenomena occur in the lowest layer of the planet's atmosphere of Earth, atmosphere, the troposphere, just below the stratosphere. Weather refers to day-to-day temperature, precipitation, and other atmospheric conditions, whereas climate is the term for the averaging of atmospheric conditions over longer periods of time. When used without qualification, "weather" is generally understood to mean the weather of Earth. Weather is driven by atmospheric pressure, air pressure, temperature, and moisture differences between one place and another. These differences can occur due to the effect of Sun angle on climate, Sun's angle at any particular spot, which varies with latitude. The strong temperature contrast between polar and tropical air gives rise to the largest scale atmospheric circulations: the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tidal Flooding
Tidal flooding, also known as sunny day flooding or nuisance flooding, is the temporary inundation of low-lying areas, especially streets, during exceptionally high tide events, such as at full and new moons. The highest tides of the year may be known as the king tide, with the month varying by location. These kinds of floods tend not to be a high risk to property or human safety, but further stress coastal infrastructure in low lying areas. This kind of flooding is becoming more common in cities and other human-occupied coastal areas as sea level rise associated with climate change and other human-related environmental impacts such as coastal erosion and land subsidence increase the vulnerability of infrastructure. Geographies faced with these issues can utilize coastal management practices to mitigate the effects in some areas, but increasingly these kinds of floods may develop into coastal flooding that requires managed retreat or other more extensive climate change adapt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Undertow (water Waves)
In physical oceanography, undertow is the undercurrent that is moving offshore when waves are approaching the shore. Undertow is a natural and universal feature for almost any large body of water: it is a return flow compensating for the onshore-directed average transport of water by the waves in the zone above the wave troughs. The undertow's flow velocities are generally strongest in the surf zone, where the water is shallow and the waves are high due to shoaling. In popular usage, the word "undertow" is often misapplied to rip currents. An undertow occurs everywhere underneath shore-approaching waves, whereas rip currents are localized narrow offshore currents occurring at certain locations along the coast. Oceanography An "undertow" is a steady, offshore-directed compensation flow, which occurs below waves near the shore. Physically, nearshore, the wave-induced mass flux between wave crest and trough is onshore directed. This mass transport is localized in the up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rip Currents
A rip current, often simply called a rip (or misleadingly a '' rip tide''), is a specific kind of water current that can occur near beaches with breaking waves. A rip is a strong, localized, and narrow current of water which moves directly away from the shore, cutting through the lines of breaking waves like a river running out to sea. The current in a rip is strongest and fastest next to the surface of the water. Rip currents can be hazardous to people in the water. Swimmers who are caught in a rip current and who do not understand what is happening, or who may not have the necessary water skills, may panic, or they may exhaust themselves by trying to swim directly against the flow of water. Because of these factors, rip currents are the leading cause of rescues by lifeguards at beaches, and in the United States, they are the cause of an average of 46 deaths by drowning per year. A rip current is not the same thing as undertow, although some people use the term incorrectly wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tidal Surge
A storm surge, storm flood, tidal surge, or storm tide is a coastal flood or tsunami-like phenomenon of rising water commonly associated with low-pressure weather systems, such as cyclones. It is measured as the rise in water level above the normal tidal level, and does not include waves. The main meteorological factor contributing to a storm surge is high-speed wind pushing water towards the coast over a long fetch. Other factors affecting storm surge severity include the shallowness and orientation of the water body in the storm path, the timing of tides, and the atmospheric pressure drop due to the storm. There is a suggestion that climate change may be increasing the hazard of storm surges. Some theorize that as extreme weather becomes more intense and sea level rises due to climate change, storm surge is expected to cause more risk to coastal populations. Communities and governments can adapt by building hard infrastructure, like surge barriers, soft infrastructu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swell (ocean)
A swell, also sometimes referred to as ground swell, in the context of an ocean, sea or lake, is a series of mechanical waves that propagate along the interface between water and air under the predominating influence of gravity, and thus are often referred to as surface gravity waves. These surface gravity waves have their origin as wind waves, but are the consequence of dispersion of wind waves from distant weather systems, where wind blows for a duration of time over a fetch of water, and these waves move out from the source area at speeds that are a function of wave period and length. More generally, a swell consists of wind-generated waves that are not greatly affected by the local wind at that time. Swell waves often have a relatively long wavelength, as short wavelength waves carry less energy and dissipate faster, but this varies due to the size, strength, and duration of the weather system responsible for the swell and the size of the water body, and varies from event ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seiche
A seiche ( ) is a standing wave in an enclosed or partially enclosed body of water. Seiches and seiche-related phenomena have been observed on lakes, reservoirs, swimming pools, bays, harbors, caves and seas. The key requirement for formation of a seiche is that the body of water be at least partially bounded, allowing the formation of the standing wave. The term was promoted by the Swiss hydrologist François-Alphonse Forel in 1890, who was the first to make scientific observations of the effect in Lake Geneva. The word had apparently long been used in the region to describe oscillations in alpine lakes. According to Wilson (1972), this Swiss French dialect word comes from the Latin word meaning "dry", i.e., as the water recedes, the beach dries. The French word or (dry) descends from the Latin. Seiches in harbours can be caused by ''long period'' or '' infragravity waves'', which are due to subharmonic nonlinear wave interaction with the wind waves, having periods longer th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rogue Wave
Rogue waves (also known as freak waves, monster waves, episodic waves, killer waves, extreme waves, and abnormal waves) are unusually large, unpredictable, and suddenly appearing surface waves that can be extremely dangerous to ships, even to large ones. They are distinct from tsunamis, which are often almost unnoticeable in deep waters and are caused by the displacement of water due to other phenomena (such as earthquakes). A rogue wave appearing at the shore is sometimes referred to as a sneaker wave. In oceanography, rogue waves are more precisely defined as waves whose height is more than twice the significant wave height (''H'' or SWH), which is itself defined as the mean of the largest third of waves in a wave record. Therefore, rogue waves are not necessarily the biggest waves found on the water; they are, rather, unusually large waves for a given sea state. Rogue waves seem not to have a single distinct cause, but occur where physical factors such as high winds and stron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Shove
An ice shove (also known as an ice surge, ice push, ice heave, shoreline ice pileup, ice piling, ice thrust, ice tsunami, ice ride-up, or ''ivu'' in Inupiat) is a surge of ice from an ocean or large lake onto the shore. Ice shoves are caused by ocean currents, strong winds, or temperature differences pushing ice onto the shore, creating piles up to 12 metres (40 feet) high. Ice shoves can be caused by temperature fluctuations, wind action, or changing water levels and can cause devastation to coastal Arctic communities. Climate change will also play a role in the formation and frequency of ice shove events; a rise in global temperatures leads to more open water to facilitate ice movement and low pressure systems to destabilize ice sheets and send them shoreward. Causes Temperature fluctuations When temperatures decrease, ice contracts and forms stress fractures; water then seeps into these tension cracks and freezes. When temperatures rise, the ice sheet expands. This sequ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
King Tide
A king tide is an especially high spring tide, especially the perigean spring tides which occur three or four times a year. King tide is not a scientific term, nor is it used in a scientific context. The expression originated in Australia, New Zealand and other Pacific nations to describe especially high tides that occur a few times per year. It is now used in North America as well, particularly in low-lying South Florida, where king tides can cause tidal flooding. In Vancouver, Canada, king tides are a growing problem along its seawall. Definition King tides are the highest tides. They are naturally occurring, predictable events. Tides are the movement of water across Earth's surface caused by the combined effects of the gravitational forces exerted by the Moon, Sun, and the rotation of Earth which manifest in the local rise and fall of sea levels. Tides are driven by the relative positions of the Earth, Sun, Moon, land formations, and relative location on Earth. In the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Tides
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide tables can be used for any given locale to find the predicted times and amplitude (or "tidal range"). The predictions are influenced by many factors including the alignment of the Sun and Moon, the phase and amplitude of the tide (pattern of tides in the deep ocean), the amphidromic systems of the oceans, and the shape of the coastline and near-shore bathymetry (see '' Timing''). They are however only predictions, the actual time and height of the tide is affected by wind and atmospheric pressure. Many shorelines experience semi-diurnal tides—two nearly equal high and low tides each day. Other locations have a diurnal tide—one high and low tide each day. A "mixed tide"—two uneven magnitude tides a day—is a third regular category. Tides va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Sea
The terms international waters or transboundary waters apply where any of the following types of bodies of water (or their drainage basins) transcend international boundaries: oceans, large marine ecosystems, enclosed or semi-enclosed regional seas and estuaries, rivers, lakes, groundwater systems (aquifers), and wetlands. "International waters" is not a defined term in international law. It is an informal term, which sometimes refers to waters beyond the "territorial sea" of any country. In other words, "international waters" is sometimes used as an informal synonym for the more formal term high seas or, in Latin, ''mare liberum'' (meaning ''free sea''). International waters (high seas) do not belong to any state's jurisdiction, known under the doctrine of 'mare liberum'. States have the right to fishing, navigation, overflight, laying cables and pipelines, as well as scientific research. The Convention on the High Seas, signed in 1958, which has 63 signatories, defined "h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
