User:John R. Brews/Coriolis force: Difference between revisions

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==Meteorology==
==Meteorology==
{{Image|Wind deflection.PNG|right|250px|Wind motion in direction of pressure gradient is deflected by the Coriolis force by an amount dependent upon latitude, less closer to the equator and most at the poles.}}
{{Image|Wind deflection.PNG|right|250px|Wind motion in direction of pressure gradient is deflected by the Coriolis force by an amount dependent upon latitude, less closer to the equator and most at the poles.}}
A pressure gradient in the atmosphere is equalized by driving a wind along the pressure gradient. However, from the natural viewpoint of meteorology, the motion is observed in the reference frame of a rotating Earth. As pointed out just above, in the Earth's reference frame, any motion is affected by a Coriolis force, as given by:
:<math> \boldsymbol{ v} = \begin{pmatrix} v_e \\ v_n\end{pmatrix}\ ,</math> &nbsp; &nbsp; <math>\boldsymbol{ a_{Cor}} = \begin{pmatrix} v_n \\ -v_e\end{pmatrix}\ f\ , </math>
where ''f'' = {{nowrap|2''&omega;'' sin''&phi;''}} is called the ''Coriolis parameter''. Consequently, the wind takes an apparent direction deflected to the right of the pressure gradient in the northern latitudes, and to the left in the southern latitudes. The Coriolis parameter is a maximum at the poles, zero at the equator and flips sign as one crosses form the northern to southern hemispheres, as indicated in the figure.


==Notes==
==Notes==

Revision as of 16:14, 5 March 2011

Meteorology

(PD) Image: John R. Brews
Wind motion in direction of pressure gradient is deflected by the Coriolis force by an amount dependent upon latitude, less closer to the equator and most at the poles.

A pressure gradient in the atmosphere is equalized by driving a wind along the pressure gradient. However, from the natural viewpoint of meteorology, the motion is observed in the reference frame of a rotating Earth. As pointed out just above, in the Earth's reference frame, any motion is affected by a Coriolis force, as given by:

   

where f = 2ω sinφ is called the Coriolis parameter. Consequently, the wind takes an apparent direction deflected to the right of the pressure gradient in the northern latitudes, and to the left in the southern latitudes. The Coriolis parameter is a maximum at the poles, zero at the equator and flips sign as one crosses form the northern to southern hemispheres, as indicated in the figure.

Notes


Contributed by myself in June 2008, for example, here here, added Limerick


http://books.google.com/books?id=-3H5V0LGBOgC&pg=PA122&dq=Foucault+pendulum&hl=en&ei=CV1gTenZOpGisQO9ruzNCA&sa=X&oi=book_result&ct=result&resnum=9&ved=0CGQQ6AEwCA#v=onepage&q=Foucault%20pendulum&f=false

http://books.google.com/books?id=NAo7yv7Jmq0C&pg=PA22&dq=Foucault+pendulum&hl=en&ei=VopgTdmBCoK4sQP6p-ncCA&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCoQ6AEwADgK#v=onepage&q=Foucault%20pendulum&f=false

http://books.google.com/books?id=NAo7yv7Jmq0C&pg=PA22&dq=Foucault+pendulum&hl=en&ei=VYVgTcujHoOusAO0vOXNCA&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCoQ6AEwADgK#v=onepage&q=Foucault%20pendulum&f=false


http://books.google.com/books?id=hrBe52GPHrYC&pg=PA351&dq=Foucault+pendulum&hl=en&ei=VYVgTcujHoOusAO0vOXNCA&sa=X&oi=book_result&ct=result&resnum=9&ved=0CFQQ6AEwCDgK#v=onepage&q=Foucault%20pendulum&f=false

http://books.google.com/books?id=GfCil84YTm4C&pg=PA116&dq=Foucault+pendulum&hl=en&ei=E4ZgTeaDGIa-sQP1zvDHCA&sa=X&oi=book_result&ct=result&resnum=8&ved=0CE0Q6AEwBzgU#v=onepage&q=Foucault%20pendulum&f=false

http://books.google.com/books?id=mms6MXH9CuoC&pg=PA22&dq=Foucault+pendulum&hl=en&ei=34ZgTeukEIuesQPMvPHYCA&sa=X&oi=book_result&ct=result&resnum=2&ved=0CCsQ6AEwATge#v=onepage&q=Foucault%20pendulum&f=false

http://books.google.com/books?id=imrm2aOs9_8C&pg=PA90&dq=Foucault+pendulum&hl=en&ei=34ZgTeukEIuesQPMvPHYCA&sa=X&oi=book_result&ct=result&resnum=7&ved=0CEQQ6AEwBjge#v=onepage&q=Foucault%20pendulum&f=false

Maxwell

http://books.google.com/books?id=wr2QOBqOBakC&pg=PA184&dq=Foucault+pendulum&hl=en&ei=U4hgTd-9Foa6sQP3lt3ACA&sa=X&oi=book_result&ct=result&resnum=2&ved=0CDAQ6AEwATgy#v=onepage&q=Foucault%20pendulum&f=false

Practical matters

http://books.google.com/books?id=sSPLspTUYEEC&pg=PA73&dq=Foucault+pendulum&hl=en&ei=U4hgTd-9Foa6sQP3lt3ACA&sa=X&oi=book_result&ct=result&resnum=4&ved=0CDsQ6AEwAzgy#v=onepage&q=Foucault%20pendulum&f=false

http://books.google.com/books?id=1J2hzvX2Xh8C&pg=PA272&dq=Foucault+pendulum&hl=en&ei=D4lgTdrSGIi6sQPrsunYCA&sa=X&oi=book_result&ct=result&resnum=3&ved=0CDIQ6AEwAjg8#v=onepage&q=Foucault%20pendulum&f=false

References