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Tsunami Warning Systems
A tsunami warning system (TWS) is used to detect tsunamis in advance and issue the warnings to prevent loss of life and damage to property. It is made up of two equally important components: a network of sensors to detect tsunamis and a communications infrastructure to issue timely alarms to permit evacuation of the coastal areas. There are two distinct types of tsunami warning systems: international and regional. When operating, seismic alerts are used to instigate the watches and warnings; then, data from observed sea level height (either shore-based tide gauges or DART buoys) are used to verify the existence of a tsunami. Other systems have been proposed to augment the warning procedures; for example, it has been suggested that the duration and frequency content of t-wave energy (which is earthquake energy trapped in the ocean SOFAR channel) is indicative of an earthquake's tsunami potential. History and forecasting The first rudimentary system to alert communities of an imp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tsunami Evac Sign Seaside Oregon
A tsunami ( ; from ja, 津波, lit=harbour wave, ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explosions (including detonations, landslides, glacier calvings, meteorite impacts and other disturbances) above or below water all have the potential to generate a tsunami. Unlike normal ocean waves, which are generated by wind, or tides, which are in turn generated by the gravitational pull of the Moon and the Sun, a tsunami is generated by the displacement of water from a large event. Tsunami waves do not resemble normal undersea currents or sea waves because their wavelength is far longer. Rather than appearing as a breaking wave, a tsunami may instead initially resemble a rapidly rising tide. For this reason, it is often referred to as a tidal wave, although this usage is not favoured by the scientific community because it might give ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Tsunami Warning Center
The National Tsunami Warning Center (NTWC) forms part of an international tsunami warning system (TWS). It serves as the operations center for all coastal regions of Canada and the United States, except Hawaii, the Caribbean, and the Gulf of Mexico. Headquartered in Palmer, Alaska, it is operated by the National Oceanic and Atmospheric Administration, National Oceanic and Atmospheric Administration (NOAA). The NTWC detects and analyzes earthquakes worldwide, issuing warnings to local officials in the hazard zones about the advisability of evacuating low-lying coastal areas and moving ships to deep water. History Following the March 27, 1964 Alaska earthquake and tsunami, the NTWC (formerly known as The Palmer Observatory) was established in 1967 in Palmer, Alaska, under the auspices of the U.S. National Geodetic Survey, Coast and Geodetic Survey. This earthquake alerted State and Federal officials that a facility was necessary to provide timely and effective tsunami warnings and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrographic And Oceanographic Service Of The Chilean Navy
SHOA or Servicio Hidrográfico y Oceanográfico de la Armada de Chile (Spanish for Hydrographic and Oceanographic Service of the Chilean Navy) is an agency of the Chilean Navy managing situations dealing with hydrography and oceanography, including tides and tsunamis. SHOA has faced severe criticism after the 2010 Chile earthquake, the largest earthquake since the 1960 Valdivia earthquake. Criticism include the lack of coordination with other authorities and the ONEMI (Chile's emergency office). ONEMI, SHOA and the government have been accused of the initial neglect of the tsunami warning sent by the Pacific Tsunami Warning Center which resulted in the deaths of hundred of persons. The director of SHOA Mariano Rojas was removed from office and replaced by Patricio Carrasco due to his responsibility over the failed tsunami warning. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tide Gauge
A tide gauge is a device for measuring the change in sea level relative to a vertical datum. It its also known as mareograph, marigraph, sea-level recorder and limnimeter. When applied to freshwater continental water bodies, the instrument may also be called a limnimeter. Operation Sensors continuously record the height of the water level with respect to a height reference surface close to the geoid. Water enters the device by the bottom pipe (far end of the tube, see picture), and electronic sensors measure its height and send the data to a tiny computer. Historical data are available for about 1,450 stations worldwide, of which about 950 have provided updates to the global data center since January 2010. At some places records cover centuries, for example in Amsterdam where data dating back to 1700 is available. When it comes to estimating the greater ocean picture, new modern tide gauges can often be improved upon by using satellite data. Tide gauges are used to measure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tilt-Sensor
An inclinometer or clinometer is an instrument used for measuring angles of slope, elevation, or depression of an object with respect to gravity's direction. It is also known as a ''tilt indicator'', ''tilt sensor'', ''tilt meter'', ''slope alert'', ''slope gauge'', ''gradient meter'', ''gradiometer'', ''level gauge'', ''level meter'', ''declinometer'', and ''pitch & roll indicator''. Clinometers measure both inclines and declines using three different units of measure: degrees, percentage points, and topos. The astrolabe is an example of an inclinometer that was used for celestial navigation and location of astronomical objects from ancient times to the Renaissance. A ''tilt sensor'' can measure the tilting in often two axes of a reference plane in two axes. In contrast, a full motion would use at least three axes and often additional sensors. One way to measure tilt angle with reference to the earth's ground plane, is to use an accelerometer. Typical applications can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenna (radio)
In radio engineering, an antenna or aerial is the interface between radio waves propagating through space and electric currents moving in metal conductors, used with a transmitter or receiver. In transmission, a radio transmitter supplies an electric current to the antenna's terminals, and the antenna radiates the energy from the current as electromagnetic wave In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, which propagate through space and carry momentum and electromagnetic radiant energy. It includes radio waves, microwaves, infrared, (visib ...s (radio waves). In Receiver (radio), reception, an antenna intercepts some of the power of a radio wave in order to produce an electric current at its terminals, that is applied to a receiver to be Amplifier, amplified. Antennas are essential components of all radio equipment. An antenna is an array of conductor (material), conductors (Driven element, elements), elect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Positioning System
The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite systems (GNSS) that provides geolocation and time information to a GPS receiver anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. It does not require the user to transmit any data, and operates independently of any telephonic or Internet reception, though these technologies can enhance the usefulness of the GPS positioning information. It provides critical positioning capabilities to military, civil, and commercial users around the world. Although the United States government created, controls and maintains the GPS system, it is freely accessible to anyone with a GPS receiver. The GPS project was started by the U.S. Department of Defense in 1973. The first prototype spacecraft was lau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accelerometer
An accelerometer is a tool that measures proper acceleration. Proper acceleration is the acceleration (the rate of change of velocity) of a body in its own instantaneous rest frame; this is different from coordinate acceleration, which is acceleration in a fixed coordinate system. For example, an accelerometer at rest on the surface of the Earth will measure an acceleration due to Earth's gravity, straight upwards (by definition) of g ≈ 9.81 m/s2. By contrast, accelerometers in free fall (falling toward the center of the Earth at a rate of about 9.81 m/s2) will measure zero. Accelerometers have many uses in industry and science. Highly sensitive accelerometers are used in inertial navigation systems for aircraft and missiles. Vibration in rotating machines is monitored by accelerometers. They are used in tablet computers and digital cameras so that images on screens are always displayed upright. In unmanned aerial vehicles, accelerometers help to stabilise flight. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismometer
A seismometer is an instrument that responds to ground noises and shaking such as caused by earthquakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The output of such a device—formerly recorded on paper (see picture) or film, now recorded and processed digitally—is a seismogram. Such data is used to locate and characterize earthquakes, and to study the Earth's internal structure. Basic principles A simple seismometer, sensitive to up-down motions of the Earth, is like a weight hanging from a spring, both suspended from a frame that moves along with any motion detected. The relative motion between the weight (called the mass) and the frame provides a measurement of the vertical ground motion. A rotating drum is attached to the frame and a pen is attached to the weight, thus recording any ground motion in a seismogram. Any movement from the ground moves the frame. The mass tends not to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arica
Arica ( ; ) is a Communes of Chile, commune and a port city with a population of 222,619 in the Arica Province of northern Chile's Arica y Parinacota Region. It is Chile's northernmost city, being located only south of the border with Peru. The city is the capital (political), capital of both the Arica Province and the Arica and Parinacota Region. Arica is located at the orocline, bend of South America's western coast known as the Arica Bend or Arica Elbow. At the location of the city are two valleys that dissect the Atacama Desert converge: Azapa Valley, Azapa and Lluta River, Lluta. These valleys provide citrus and olives for export. Arica is an important port for a large inland region of South America. The city serves a free port for Bolivia and manages a substantial part of that country's trade.In addition it is the end station of the Bolivian oil pipeline beginning in Oruro, Bolivia, Oruro. The city's strategic position is enhanced by being next to the Chile Route 5, Pan-Ame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antofagasta
Antofagasta () is a port city in northern Chile, about north of Santiago. It is the capital of Antofagasta Province and Antofagasta Region. According to the 2015 census, the city has a population of 402,669. After the Spanish American wars of independence, Bolivia claimed Antofagasta as part of its territory. Despite having an overwhelmingly ethnic Chilean population, Chile recognised Bolivian sovereignty of Antofagasta in 1866, but in 1879 Chile recanted its recognition of Bolivian sovereignty citing a Bolivian breach of the latest boundary treaty. Antofagasta was captured by Chile in February 14 1879 triggering the War of the Pacific (1879–83). Chilean sovereignty was officially recognised by Bolivia under the terms of the 1904 Treaty of Peace and Friendship. The city of Antofagasta is closely linked to mining activity, being a port and the chief service hub for one of Chile's major mining areas. While silver and saltpeter mining have been historically important for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UNESCO
The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations (UN) aimed at promoting world peace and security through international cooperation in education, arts, sciences and culture. It has 193 member states and 12 associate members, as well as partners in the non-governmental, intergovernmental and private sector. Headquartered at the World Heritage Centre in Paris, France, UNESCO has 53 regional field offices and 199 national commissions that facilitate its global mandate. UNESCO was founded in 1945 as the successor to the League of Nations's International Committee on Intellectual Cooperation.English summary). Its constitution establishes the agency's goals, governing structure, and operating framework. UNESCO's founding mission, which was shaped by the Second World War, is to advance peace, sustainable development and human rights by facilitating collaboration and dialogue among nations. It pursues this objective t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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