Domain definition for Monsoon Wang's NAFM

[lee1043]

Found by @pochedls at xCDAT/xcdat#166 (comment).

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The NAFM region in monsoon_wang driver is for North African Monsoon, 310E to 60E (as in below figure).

(image from here)

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However, with region defined as longitude=(310, 60), the area considered is from 60E to 310E (mirrored, as in below figure).

import cdms2
import vcs
f = cdms2.open('CanCM4_NAFM_wang-monsoon.nc')
d = f('variable_993')
x = vcs.init()
x.png('NAFM.png')

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In the PMP's driver for the Monsoon Wang metric, it opens model file with regular cdms2 open, as f = cdms2.open(modelFile).

@gleckler1 Could you point the reference paper for the Monsoon Wang index? And any idea for quick fix?

[gleckler1]

@lee1043 https://doi.org/10.1016/j.dynatmoce.2007.05.002

[lee1043]

Note: This issue should be resolved by using the new regions_subset function.

@bosup is working on xcdat migration of monsoon Wang code and will test this function in the monsoon Wang (related discussion: xCDAT/xcdat#692).

[lee1043]

The above screenshot from ncview CanCM4_NAFM_wang-monsoon.nc where the file is from Demo 2a notebook from PR #1200 confirms that the issue will be resolved by merging the PR.