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Canadian Weather Radar Network
The Canadian weather radar network consists of 31 weather radars spanning Canada's most populated regions. Their primary purpose is the early detection of precipitation, its motion and the threat it poses to life and property. Each had until 2018 a range of in radius around the site to detect reflectivity, 3 angles with a range of , for detecting velocity pattern ( Doppler effect), and an extra long range up to at low elevation angle but strongly folded or aliased (where the maximum unambiguous velocity interval (±Vmax) is less than the full range of velocities being measured which leads to some being displayed with the wrong values). The renewal of the network, from 2018 to 2023, with new S-Band radars brings these numbers respectively to for reflectivity and for full Doppler coverage. Furthermore, the new radars are dual-polarized which means precipitation type can be estimated directly. Starting in June 2021, some of the radars' ranges will be extended to in the lowest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by total area. Its southern and western border with the United States, stretching , is the world's longest binational land border. Canada's capital is Ottawa, and its three largest metropolitan areas are Toronto, Montreal, and Vancouver. Indigenous peoples have continuously inhabited what is now Canada for thousands of years. Beginning in the 16th century, British and French expeditions explored and later settled along the Atlantic coast. As a consequence of various armed conflicts, France ceded nearly all of its colonies in North America in 1763. In 1867, with the union of three British North American colonies through Confederation, Canada was formed as a federal dominion of four provinces. This began an accretion of provinces an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catherine McKenna
Catherine Mary McKenna (born August 5, 1971) is a Canadian lawyer and former politician who served as a Cabinet minister from 2015 to 2021. A member of the Liberal Party, McKenna was the minister of environment and climate change from 2015 to 2019 and minister of infrastructure and communities from 2019 to 2021. She was the member of Parliament (MP) for Ottawa Centre from 2015 to 2021. She is currently the Chair of the United Nations High-Level Expert Group on the Net-Zero Emissions Commitments of Non-State Entities. Background After graduating from École élémentaire catholique Notre-Dame (her father insisted that all his children be bilingual despite not knowing any French himself) McKenna attended Saint Mary Catholic Secondary School in Hamilton, Ontario. After graduating from the University of Toronto, she filmed a documentary in Asia. Career McKenna is trained as a lawyer. In 2005, McKenna co-founded Canadian Lawyers Abroad - Avocats canadiens à l'étranger (CLA-ACE ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quebec City
Quebec City ( or ; french: Ville de Québec), officially Québec (), is the capital city of the Provinces and territories of Canada, Canadian province of Quebec. As of July 2021, the city had a population of 549,459, and the Communauté métropolitaine de Québec, metropolitan area had a population of 839,311. It is the eleventhList of the largest municipalities in Canada by population, -largest city and the seventhList of census metropolitan areas and agglomerations in Canada, -largest metropolitan area in Canada. It is also the List of towns in Quebec, second-largest city in the province after Montreal. It has a humid continental climate with warm summers coupled with cold and snowy winters. The Algonquian people had originally named the area , an Algonquin language, AlgonquinThe Algonquin language is a distinct language of the Algonquian languages, Algonquian language family, and is not a misspelling. word meaning "where the river narrows", because the Saint Lawrence River na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulse Repetition Frequency
The pulse repetition frequency (PRF) is the number of pulses of a repeating signal in a specific time unit. The term is used within a number of technical disciplines, notably radar. In radar, a radio signal of a particular carrier frequency is turned on and off; the term "frequency" refers to the carrier, while the PRF refers to the number of switches. Both are measured in terms of cycle per second, or hertz. The PRF is normally much lower than the frequency. For instance, a typical World War II radar like the Type 7 GCI radar had a basic carrier frequency of 209 MHz (209 million cycles per second) and a PRF of 300 or 500 pulses per second. A related measure is the pulse width, the amount of time the transmitter is turned on during each pulse. After producing a brief pulse of radio signal, the transmitter is turned off in order for the receiver units to hear the reflections of that signal off distant targets. Since the radio signal has to travel out to the target and back ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vaisala
Vaisala Oyj () is a Finnish company that develops, manufactures and markets products and services for environmental and industrial measurement. Their major customer groups and markets are national meteorological and hydrological services, aviation authorities, defense forces, road authorities, the weather critical energy sector, life science and high-technology industries and building automation. Vaisala had over 1,900 employees and net sales of €379.5 million in 2020. Vaisala serves customers in more than 150 countries. The parent company Vaisala Oyj, domicile in Vantaa, Finland, is listed on the NASDAQ OMX Helsinki. Vaisala Group has offices and operations in Finland, the United States, Australia, Brazil, Canada, China, France, Germany, India, Italy, Japan, Kenya, Malaysia, México, South Korea, Sweden, United Arab Emirates, and the United Kingdom. History Vaisala originated in the 1930s when Professor Vilho Väisälä (1889–1969), Vaisala's founder and long-time manag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetron
The cavity magnetron is a high-power vacuum tube used in early radar systems and currently in microwave ovens and linear particle accelerators. It generates microwaves using the interaction of a stream of electrons with a magnetic field while moving past a series of cavity resonators, which are small, open cavities in a metal block. Electrons pass by the cavities and cause microwaves to oscillate within, similar to the functioning of a whistle producing a tone when excited by an air stream blown past its opening. The resonant frequency of the arrangement is determined by the cavities' physical dimensions. Unlike other vacuum tubes, such as a klystron or a traveling-wave tube (TWT), the magnetron cannot function as an amplifier for increasing the intensity of an applied microwave signal; the magnetron serves solely as an oscillator, generating a microwave signal from direct current electricity supplied to the vacuum tube. The use of magnetic fields as a means to control the flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raytheon
Raytheon Technologies Corporation is an American multinational aerospace and defense conglomerate headquartered in Arlington, Virginia. It is one of the largest aerospace and defense manufacturers in the world by revenue and market capitalization. In addition, it is one of the largest providers of intelligence services. Raytheon Technologies manufactures aircraft engines, avionics, aerostructures, cybersecurity, guided missiles, air defense systems, satellites, and drones. The company is also a large military contractor, getting a significant portion of its revenue from the U.S. government. The company is the result of the merger of equals between the aerospace subsidiaries of United Technologies Corporation (UTC) and the Raytheon Company, which was completed on April 3, 2020. Before the merger, UTC spun off its non-aerospace subsidiaries Otis Elevator Company and Carrier Corporation. UTC is the nominal survivor of the merger but it changed its name to Raytheon Technologies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterprise Electronics Corporation
Enterprise Electronics Corporation or EEC is an Alabama-based commercial weather radar system company, founded in 1971. EEC has designed and manufactured over 1,000 weather radar systems to over 90 countries. EEC offers S Band, C Band, and X Band options commercially. In 2013, EEC expanded its product line offering by acquiring the weather satellite ground station division from the Australia-based Environmental Systems & Services Pty Ltd company (ES&S). History Founded by a group of radar engineers in 1971, EEC made its public debut in 1974, when production of cavity magnetron and klystron commercial S and C-Band weather radars began.. Also in 1974, EEC was selected by the US National Weather Service to deliver 160 WSR-74 radar systems to replace the older models across the country. Following this, EEC expanded its operations, becoming a commonly consulted private radar company for media radars. Today, EEC is the only commercial weather radar vendor in the US to offer a comple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polarization (waves)
Polarization (also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the oscillations. In a transverse wave, the direction of the oscillation is perpendicular to the direction of motion of the wave. A simple example of a polarized transverse wave is vibrations traveling along a taut string ''(see image)''; for example, in a musical instrument like a guitar string. Depending on how the string is plucked, the vibrations can be in a vertical direction, horizontal direction, or at any angle perpendicular to the string. In contrast, in longitudinal waves, such as sound waves in a liquid or gas, the displacement of the particles in the oscillation is always in the direction of propagation, so these waves do not exhibit polarization. Transverse waves that exhibit polarization include electromagnetic waves such as light and radio waves, gravitational waves, and transverse sound waves (shear waves) in solids. An electromagnetic wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Klystron
A klystron is a specialized linear-beam vacuum tube, invented in 1937 by American electrical engineers Russell and Sigurd Varian,Pond, Norman H. "The Tube Guys". Russ Cochran, 2008 p.31-40 which is used as an amplifier for high radio frequencies, from UHF up into the microwave range. Low-power klystrons are used as oscillators in terrestrial microwave relay communications links, while high-power klystrons are used as output tubes in UHF television transmitters, satellite communication, radar transmitters, and to generate the drive power for modern particle accelerators. In a klystron, an electron beam interacts with radio waves as it passes through resonant cavities, metal boxes along the length of a tube. The electron beam first passes through a cavity to which the input signal is applied. The energy of the electron beam amplifies the signal, and the amplified signal is taken from a cavity at the other end of the tube. The output signal can be coupled back into the input cavi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newfoundland (island)
Newfoundland (, ; french: link=no, Terre-Neuve, ; ) is a large island off the east coast of the North American mainland and the most populous part of the Canadian province of Newfoundland and Labrador. It has 29 percent of the province's land area. The island is separated from the Labrador Peninsula by the Strait of Belle Isle and from Cape Breton Island by the Cabot Strait. It blocks the mouth of the Saint Lawrence River, creating the Gulf of Saint Lawrence, the world's largest estuary. Newfoundland's nearest neighbour is the French overseas collectivity of Saint Pierre and Miquelon. With an area of , Newfoundland is the world's 16th-largest island, Canada's fourth-largest island, and the largest Canadian island outside the North. The provincial capital, St. John's, is located on the southeastern coast of the island; Cape Spear, just south of the capital, is the easternmost point of North America, excluding Greenland. It is common to consider all directly neighbouring i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edmonton
Edmonton ( ) is the capital city of the Canadian province of Alberta. Edmonton is situated on the North Saskatchewan River and is the centre of the Edmonton Metropolitan Region, which is surrounded by Alberta's central region. The city anchors the north end of what Statistics Canada defines as the " Calgary–Edmonton Corridor". As of 2021, Edmonton had a city population of 1,010,899 and a metropolitan population of 1,418,118, making it the fifth-largest city and sixth-largest metropolitan area (CMA) in Canada. Edmonton is North America's northernmost large city and metropolitan area comprising over one million people each. A resident of Edmonton is known as an ''Edmontonian''. Edmonton's historic growth has been facilitated through the absorption of five adjacent urban municipalities ( Strathcona, North Edmonton, West Edmonton, Beverly and Jasper Place) hus Edmonton is said to be a combination of two cities, two towns and two villages./ref> in addition to a series ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
