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Tidal Range
Tidal range is the difference in height between high tide and low tide. Tides are the rise and fall of sea levels caused by gravitational forces exerted by the Moon and Sun, by Earth's rotation and by centrifugal force caused by Earth's progression around the Earth-Moon barycenter. Tidal range depends on time and location. Larger tidal range occur during spring tides (spring range), when the gravitational forces of both the Moon and Sun are aligned (at syzygy), reinforcing each other in the same direction ( new moon) or in opposite directions ( full moon). The largest annual tidal range can be expected around the time of the equinox if it coincides with a spring tide. Spring tides occur at the second and fourth (last) quarters of the lunar phases. By contrast, during neap tides, when the Moon and Sun's gravitational force vectors act in quadrature (making a right angle to the Earth's orbit), the difference between high and low tides (neap range) is smallest. Neap ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar Phase
A lunar phase or Moon phase is the apparent shape of the Moon's directly sunlit portion as viewed from the Earth. Because the Moon is tidally locked with the Earth, the same hemisphere is always facing the Earth. In common usage, the four major phases are the new moon, the first quarter, the full moon and the last quarter; the four minor phases are waxing crescent, waxing gibbous, waning gibbous, and waning crescent. A lunar month is the time between successive recurrences of the same phase: due to the eccentricity of the Moon's orbit, this duration is not perfectly constant but averages about 29.5 days. The appearance of the Moon (its phase) gradually changes over a lunar month as the relative orbital positions of the Moon around Earth, and Earth around the Sun, shift. The visible side of the Moon is sunlit to varying extents, depending on the position of the Moon in its orbit, with the sunlit portion varying from 0% (at new moon) to nearly 100% (at full moon). Phenomenon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ungava Bay
Ungava Bay (; , ; /) is a bay in Nunavut, Canada separating Nunavik (far northern Quebec) from Baffin Island. Although not geographically apparent, it is a marginal sea of the Arctic Ocean. The bay is roughly oval-shaped, about at its widest point and about in length; it has an area of approximately . It is generally fairly shallow, under , though at its border with the Atlantic Ocean depths of almost are reached. Geography Although it is quite close to the open Atlantic (separated only by Hudson Strait), Ungava Bay is part of the Arctic Ocean. Ungava Bay is separated from Hudson Bay by the Ungava Peninsula. Of the many islands in Ungava Bay, Akpatok Island is largest. Bathymetric studies suggest that Ungava Bay may be the remnant of an impact crater (age unknown) approximately in diameter. The southwestern corner of Ungava Bay vies with the Bay of Fundy for the highest tidal range in the world. Some sources estimate the spring tide range at the mouth of the Leaf River ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burntcoat Head, Nova Scotia
Burntcoat (improperly known as Burncoat) is an unincorporated rural Canadian community in Hants County, Nova Scotia. The area is well known for its cape of Burntcoat Head, the location of the largest recorded tidal range (the greatest difference in height between high tide and low tide) of anywhere in the world. It is also home to Burntcoat Head Park, which offers public access to the ocean floor. Etymology The origin of the name "Burntcoat" or "Burncoat", as the community is sometimes named, is unknown. The derivation of the spelling of the name is also unclear. Today the village on the ''west'' side of the Noel Bay is named Burntcoat, however, the Acadians named the village on the ''east'' side of the Noel Bay "Pointe Brull" (i.e., Burnt Point or Burnt Coast). Perhaps the Protestant settlers who came after the exodus of the Acadians from the community confused the names for the east and west side of the Noel Bay and thought the west side of the bay was "Pointe Brull". The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bay Of Fundy
The Bay of Fundy () is a bay between the Canadian provinces of New Brunswick and Nova Scotia, with a small portion touching the U.S. state of Maine. It is an arm of the Gulf of Maine. Its tidal range is the highest in the world. The bay was named ''Bakudabakek'' by the indigenous Mi'kmaq and Passamaquoddy groups, meaning "open way". The Wolastoqiyik peoples named it ''Wekwabegituk'', meaning "waves at the head of the bay". The name "Fundy" has been speculated to have derived from the French word ("split") or ("head of the bay"). Some individuals have disputed this, including William Francis Ganong, who suggested that the name likely derived from Portuguese origin instead, specifically regarding João Álvares Fagundes, who may have referred to the bay as ("Great Bay") and nearby waters as ("deep river"). Hydrology Tides The tidal range in the Bay of Fundy is about ; the average tidal range worldwide is only . Some tides are higher than others, depending on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Funnel
A funnel is a tube or pipe that is wide at the top and narrow at the bottom, used for guiding liquid or powder into a small opening. Funnels are usually made of stainless steel, aluminium, glass, or plastic. The material used in its construction should be sturdy enough to withstand the weight of the substance being transferred, and it should not react with the substance. For this reason, stainless steel or glass are useful in transferring diesel fuel, while plastic funnels are useful in the kitchen. Sometimes disposable paper funnels are used in cases where it would be difficult to adequately clean the funnel afterwards (for example, in adding motor oil into a car). Dropper funnels, also called dropping funnels or tap funnels, have a Tap (valve), tap to allow the controlled release of a liquid. A flat funnel, made of polypropylene, utilises living hinges and flexible walls to fold flat. The term "funnel" may refer to the Chimney (locomotive), chimney or smokestack on a steam lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M2 Tidal Constituent
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] |
Mean High Water
A chart datum is the water level, water surface serving as origin (mathematics), origin (or coordinate surface) of depth (coordinate), depths displayed on a nautical chart and for reporting and predicting tide heights. A chart datum is generally derived from some tidal phase, in which case it is also known as a tidal datum. Common chart datums are ''lowest astronomical tide'' (LAT)Australian Bureau of MeteorologNational Tide Centre Glossary(retrieved 30 April 2013) and ''mean lower low water'' (MLLW). In non-tidal areas, e.g. the Baltic Sea, mean sea level (MSL) is used. A chart datum is a type of vertical datum and must not be confused with the horizontal datum for the chart. However, it is necessarily an equigeopotential (a water "level surface"): the chart datum is tilted across smaller to larger tidal range regions; in rivers, it is a sloping and undulating surface following the low stage (hydrology), stage. Definitions The following tidal phases are commonly used in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flooding
A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding. Examples for human changes are land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees. Global environmental issues also influence causes of floods, namely climate change which causes an intensification of the water cycle and sea level rise. For example, climate change makes extreme weather events more frequent and stronger. This leads to more intense floods and increased flood risk. Natural types of floods include river flooding, groundwater flooding coastal flooding and urban flooding sometimes known as flash flooding. Tidal flooding may inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Pressure
Atmospheric pressure, also known as air pressure or barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as , which is equivalent to 1,013.25 millibars, 760 mm Hg, 29.9212 inchesHg, or 14.696 psi.International Civil Aviation Organization. ''Manual of the ICAO Standard Atmosphere'', Doc 7488-CD, Third Edition, 1993. . The atm unit is roughly equivalent to the mean sea-level atmospheric pressure on Earth; that is, the Earth's atmospheric pressure at sea level is approximately 1 atm. In most circumstances, atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point. As elevation increases, there is less overlying atmospheric mass, so atmospheric pressure decreases with increasing elevation. Because the atmosphere is thin relative to the Earth's radius—especially the dense atmospheric layer at low altitu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Hydrographic Office
A hydrographic office is an organization which is devoted to acquiring and publishing hydrographic information. Historically, the main tasks of hydrographic offices were the conduction of hydrographic surveys and the publication of nautical charts. In many countries, various navigation-related services are now concentrated in large governmental organizations, sometimes termed "maritime administration" (however, the International Hydrographic Organization uses the term "hydrographic offices" for its member organizations). Besides nautical charts, many hydrographic offices publish a body of books and periodicals that are collectively known as nautical publications. The most important of these are: * Sailing Directions (or ''pilots''): detailed descriptions of areas of the sea, shipping routes, harbours, aids to navigation, regulations etc. * lists of lights: descriptions of lighthouses and lightbouys *tide tables and tidal stream atlases * ephemerides and nautical almanacs for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth's Orbit
Earth orbits the Sun at an astronomical unit, average distance of , or 8.317 light-second, light-minutes, in a retrograde and prograde motion, counterclockwise direction as viewed from above the Northern Hemisphere. One complete orbit takes days (1 sidereal year), during which time Earth has traveled .Jean Meeus, ''Astronomical Algorithms'' 2nd ed, (Richmond, VA: Willmann-Bell, 1998) 238. See Ellipse#Circumference. The formula by Ramanujan is accurate enough. Ignoring the influence of other Solar System bodies, Earth's orbit, also called Earth's revolution, is an ellipse with the Earth–Sun barycenter as one focus (geometry), focus with a current orbital eccentricity, eccentricity of 0.0167. Since this value is close to zero, the center of the orbit is relatively close to the center of the Sun (relative to the size of the orbit). As seen from Earth, the planet's orbital prograde motion makes the Sun diurnal motion, appear to move with respect to fixed stars, other star ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
