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Recommendation for map-projection in subtropical region

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New member
Hey guys,

I'm trying to simulate the jet-stream in the subtropical regions, (West 120°-60° / South 5°-55°) over 10 days.
Currently I am using mercator as my map-projection, which is easy to use, but I have been told that my max map factor ( = 1.47 ) may be a little bit too high.
Would you consider 1.47 too much?

please finde the attached mapfactor from my geo_em file.

What would you recommend?

This is the geogrid section of my namelist.wps:

parent_id = 1,
parent_grid_ratio = 1,
i_parent_start = 1,
j_parent_start = 1,
e_we = 188,
e_sn = 193,
geog_data_res = 'default',
dx = 30000,
dy = 30000,
map_proj = 'mercator',
ref_lat = -34.0,
ref_lon = -90.0,
truelat1 = -34.0,
truelat2 = -34.0,
stand_lon = 0.090,

Thanks for any advice.



  • MAPFAC_M_in_geo_em.d01.png
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That is probably a bit higher than you want. Have you tried the lambert projection to see if you get better results?