Rotation Process of the Earth turning on its axis. Rotationm determines day and night, and the length of the day. Compare with revolution.
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Rotation in the opposite sense from Earth's rotation, i.e. clockwise in the Northern Hemisphere as seen from above. The opposite of cyclonic rotation.
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A rotation-type anemometer consists of an array of three (or four) hemispherical cups mounted symmetrically about a vertical rotation axis. The rate of rotation of the cup array is a measure of the wind speed, as determined indirectly by gearing a mechanical or electrical counter to the shaft.
If rotation is observed, then the term dust whirl or debris cloud should be used.
*Dust Whirl - A rotating column of air rendered visible by dust. Similar to debris cloud; see also dust devil, gustnado, tornado.
If rotation is observed, then the term dust whirl or debris cloud should be used.
A storm which carries a large amount of dust into the atmosphere. Particles of dust and or sand are energetically lifted to great heights by strong and turbulent winds.
The ~ of a tropical storm is more recognizable than for a tropical depression. Tropical storms can cause a lot of problems even without becoming a hurricane. However, most of the problems a tropical storm cause stem from heavy rainfall.
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the ~ of the earth which causes winds to be deflected to the right in the northern hemisphere and to the left in the southern hemisphere. This is known as the Coriolis effect and results in the formation of giant eddies (cyclones and anticyclones).
TORQUE - Rotational force applied to the propeller.
TORQUE EFFECT - The tendency for an aircraft to roll the opposite way the propeller is rotating due to drag on the propeller.
TRAFFIC PATTERN - A prescribed traffic flow for all aircraft landing and departing at an airfield.
A area of rotation of storm size that may often be found on the southwest part of a supercell. Its circulation can be larger than the tornado that may develop within it, but not necessarily. Originally a radar term for a rotation signature that met certain criteria, it is best seen on Doppler radar.
Bartel's Rotation Number
The serial number assigned to 27-day rotation periods of solar and geophysical parameters. Rotation 1 in this sequence was assigned arbitrarily by Bartel to begin in January 1833.
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The Earth's rotation imparts an acceleration known as the Coriolis effect, Coriolis acceleration, or colloquially, Coriolis force. This acceleration causes cyclonic systems to turn towards the poles in the absence of strong steering currents.
ANTI-CYCLONIC ROTATION Rotation opposite that of the earth. For example, clockwise in the Northern Hemisphere as would be seen from a view above. The opposite of cyclonic rotation.
Cyclonic - Rotation in the same sense that the earth rotates, counter-clockwise in the Northern Hemisphere. Wind around a low; subgeostrophic.
Anticyclonic Rotation Rotation in the opposite sense as the Earth's rotation. In the Northern Hemisphere, this would be clockwise as would be seen from above.
Antlophobia The fear of floods.
~ anemometer A type of anemometer in which the rotation of an element serves to measure the wind.
In reality, the rotation of the Earth changes everything. The rise of air in the equatorial region reduces surface air pressure, creating an equatorial low pressure zone (Equatorial Low). In this zone the weather is humid and rainy, with feeble wind flowing in with no prevailing direction.
~The spinning of a body, such as the earth, about its axis.ROTGRotatingRotor CloudA turbulent altocumulus cloud formation found in the lee of some mountain barriers when winds cross the barrier at high speed. The air in the cloud rotates around an axis parallel to the range.
VORTICITY- Any rotation within a horizontal or vertical windflow.
VORT MAX, VORT LOBE- Highest value of vorticity. A region of maximum vorticity. A wind flow through a vort max will produce divergence downwind from the vort max.
3) Analyze areas of rotation (when generated from one AZRAN to another).
A sidereal day is equivalent to one complete rotation of the earth relative to the equinox, which is 23 hours, 56 minutes, and 4.091 seconds. A sidereal year is the interval required for the earth to make one absolute revolution around the sun, which is 365 days, 6 hours, 9 minutes, and 9.5 seconds.
It is used to aid in displaying shear and rotation in storms and storm top divergence that might otherwise be obscured by the storm's motion, investigate the 3-D velocity structure of a storm, and help with determining rotational features in fast and uniform moving storms.
GeosynchronousTerm applied to any equatorial satellite with an orbital velocity equal to the rotational velocity of the earth.
Fujiwhara effectThe Fujiwhara effect describes the rotation of two storms around each other.Funnel cloudA rotating, cone-shaped column of air extending downward from the base of a thunderstorm but not touching the ground. When it reaches the ground it is called a tornado.
AnticycloneA large-scale circulation of winds around a central region of high atmospheric pressure, clockwise in the Northern Hemisphere, counterclockwise in the Southern HemisphereAnticyclonic RotationRotation in the opposite sense as the Earth's rotation, i.e.
Is any rotation observed in the cloud elements etc? What was the wind regime, before, during and after the event? Note particularly the onset of notable gustiness, changes of wind in direction/speed as compared with onset of precipitation etc. Was a sea breeze front involved?
The serious tornado is aided by rotation aloft, especially at the edges of large mesoscale rotating convective storms. Again, centrifugal force aids the formation of a core of low pressure that hurries air upwards.
Since the earth is rotating, the force observed as gravity is the resultant of the force of gravitation and the centrifugal force arising from this rotation. It is directed normal to sea level and to its geopotential surfaces.
An effect of the earth's rotation that deflects the direction of any large moving object (including the wind) to the right in the Northern Hemisphere, and to the left in the Southern Hemisphere. The Coriolis Force is responsible for giving a cyclone its spin.
The deflection (to the right in the northern hemisphere) is caused by the rotation of the earth.Corrective Action Report (CAR)Used to identify and document problems with ARM systems, physical infrastructure, or instruments.
TORNADO - A region of rotation extending from the base of a thunderstorm or other convective cloud to the earth's surface. This is a vortex, or wind velocity field, with a speed of at least 40 MPH at the surface. Tornadoes depend on a parent cloud, such as a thunderstorm, in order to develop.
This daily rotation of the earth means that in 24 hours a point on its equator moves a distance of some 40 000 kilometres, giving it a tangential velocity of about 1670 kilometres per hour (or roughly 1000 mph).
an instrument which measures wind speed or wind speed and direction; a cup anemometer measures the wind speed from the speed of ~ of a windmill which consist of 3 or 4 hemispherical or conical cups, each fixed to the ends of horizontal arms attached to a vertical axis; ...
*Mesocyclone - A storm-scale region of ~, typically around 2-6 miles in diameter and often found in the right rear flank of a supercell (or often on the eastern, or front, flank of an HP storm).
The measurement of the ~ of a small air parcel. It has vorticity when the parcel spins as it moves along its path.
When seen from within several miles, many wall clouds exhibit rapid upward motion and cyclonic ~. However, not all wall clouds rotate. Rotating wall clouds usually develop before strong or violent tornadoes, by anywhere from a few minutes up to nearly an hour.
Cyclonic circulation (or Cyclonic ~) - Circulation (or ~) which is in the same sense as the Earth's ~, i.e. counterclockwise (in the Northern Hemisphere) as would be seen from above.
Precipitation often totally envelops the region of ~, making visual identification of any embedded tornadoes difficult and very dangerous. Unlike most classic supercells, the region of ~ in many HP storms develops in the front-flank region of the storm (i.e.
Vorticity - A measure of the local ~ in a fluid flow. In weather analysis and forecasting, it usually refers to the vertical component of ~ (i.e., ~ about a vertical axis) and is used most often in reference to synoptic scale or mesoscale weather systems.
Coriolis Force- An apparent force caused by the ~ of the Earth. In the Northern Hemisphere winds are deflected to the right, and in the Southern Hemisphere to the left.
Cloud ~ is one example of differential motion, but not all differential motion indicates ~. For example, horizontal wind shear along a gust front may result in differential cloud motion without the presence of ~.
[Slang], a region of storm-scale ~, in a thunderstorm, which is wrapped in heavy precipitation. This area often coincides with a radar hook echo and/or mesocyclone, especially one associated with an HP storm.
A force per unit mass that arises solely from the earth's ~, acting as a deflecting force. It is dependent on the latitude and the speed of the moving object.
Vorticity This is a term used by meteorologists to describe the ~ of a fluid. An example is the ~ of the atmosphere (a gaseous fluid) around relatively large scale low and high pressure cells.
Anticyclonic- describes the movement of air around a high pressure; and ~ about the local vertical oppostie the earth's ~.
Arctic Air- a mass of very cold, dry air that usually originates over the Arctic Ocean north of Canada and Alaska.
This helps forecasters to identify the tell-tale circular ~ typical of budding funnel clouds. Further, this radar can detect areas of high winds in the atmosphere not observable from the ground. It can also sense areas of wind-shear.
An effect caused by the Earth's ~, which causes winds and currents to follow a curved path across the Earth's surface- to the right (clockwise) in the northern hemisphere, to the left (anti-clockwise) in the southern hemisphere.
HORIZONTAL VORTICITY- A ~ of air caused by vertical speed or directional wind shear.
HORSE LATITUDES - subtropical regions where anticyclones produce settled weather.
HUMIDITY -The amount of water vapor in the atmosphere. (See relative humidity).
Coriolis effect A deflective force arising from the ~ of the earth on its axis; affects principally synoptic-scale and global-scale winds. Winds are deflected to the right of the initial direction in the Northern Hemisphere, and to the left in the Southern Hemisphere.
Vorticity - A measure of the ~ of air in a horizontal plane. Positive (counter-clockwise or cyclonic) vorticity can be correlated with surface low development and upward vertical motion (in areas of positive vorticity advection).
absolute vorticity—the ~ of the Earth imparts vorticity to the atmosphere; absolute vorticity is the combined vorticity due to this ~ and vorticity due to circulation relative to the Earth (relative vorticity).
They also occasionally contain ~ on a broad scale. Because of its structure, the severe storm may last for hours beyond the lifetime of a normal thunderstorm while producing large hail, high winds, torrential rain, and possible tornadoes.
Coriolis Effect- The curving motion of anything, such as air, caused by the ~ of the Earth.
Cyclone- A low-pressure system in which winds spin inward in a counterclockwise direction in the northern hemisphere.
Depression- An area of low atmospheric temperature.
Coriolis Force - A force that deflects moving objects to one side because of the Earth's ~. The object is still going straight but the Earth moves underneath it, making it look like it is moving to one side. In the Northern Hemisphere, the Coriolis Force deflects objects to the right.
Coriolis Effect-The deflective effect of the earth's ~ on all free-moving objects, including the atmosphere and oceans. To the right in the northern hemisphere and left in the southern hemisphere.
VORTICITY: A measure of the amount of "spin" (or ~) in the atmosphere.
WAA: Warm Air Advection
WARM FRONT: A boundary between a warm airmass that is replacing a cooler airmass.
Cyclonic: Air flow around the centre of a surface Low. In the Northern Hemisphere, this flow is counter-clockwise as seen from above. (In the Southern Hemisphere, it is clockwise.) Also, any ~ in the direction of the Earth's ~.
CORIOLIS FORCE: An apparent force on moving particles produced by the ~ of the Earth. In the Northern Hemisphere, the wind is deflected to the right by the coriolis force.
The deflection of moving objects (air and water currents) due to the ~ of the Earth--to the right in the northern hemisphere, and to the left in the southern. (JPL) ...
Coriolis Force - An apparent force observed on any free moving object in a rotating system. On the earth, this reflective force results from the earth's ~ and causes moving particles (including wind) to deflect to the right in the northern hemisphere and to the left in the southern ...
An apparent force exerted on moving objects due to the earth's ~.
Fujita Tornado Scale: classifies tornadoes from F0 (wind speeds of 40-72 mph) to F5 (261-318 mph) on the basis of ~al speeds derived from the damage they cause. Developed by T. Theodore Fujita.
anticyclone (high-pressure area) An atmospheric high-pressure closed circulation with clockwise ~ in the Northern Hemisphere, counterclockwise in the Southern Hemisphere, and undefined at the Equator.
See also: What is the meaning of Surface, Weather, Pressure, Air, Cloud?