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Unable to run NCL on my MacOSX Catalina system

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I am not able to run ncl on my MacOSX Catalina computer. I have followed all the web page instructions ( but I can't make it work.

I enclose a screenshot with useful information (indicated at the bottom of the web page).

Thanks in advance.

Best regards,


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Did you happen to use the Homebrew installation for ncar-ncl? I had previously tried that and gotten the dyld error that you are getting.There are new security features on MacOS since El Capitan that prevent the programs from setting the DYLD (dynamic linker) environment variables, which could explain your error. You can read more about that here. I recommend installing NCL using conda, as described here: . This is now the preferred way of installing NCL, according to NCAR.