Grid rotation angle and diagnostics

General scientific issues regarding ROMS

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yadusharma
Posts: 25
Joined: Tue Sep 22, 2015 3:09 pm
Location: Indian Institute of Technology Gandhinagar

Grid rotation angle and diagnostics

#1 Unread post by yadusharma »

Hi All,

I have a question regarding the diagnostic terms from the ROMS outputs. Do we need to rotate the diagnostic terms (all 2D and 3D momentum terms and also temperature diagnostic terms (advection etc)) using grid rotation angle? I would be grateful for any suggestions in this regard

Thanks in advance

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wilkin
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Joined: Mon Apr 28, 2003 5:44 pm
Location: Rutgers University
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Re: Grid rotation angle and diagnostics

#2 Unread post by wilkin »

All vector component diagnostics are in the ROMS coordinate system. So, if you want them east/north you need to rotate them.

Note that many components are on their respective faces of the rho cells, not necessarily at the cell center. So "u" and "v" components would need to be averaged to the appropriate rho point first before applying the rotation (the "angle" is defined at rho points). I

f you are in doubt as to which point a term is defined at you can look at the second-to-last entry for that variable in varinfo.dat: u3dvar is at a u-point, v3dar is at a v-point, r3dvar is at a rho-point.
John Wilkin: DMCS Rutgers University
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu

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