These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 0.84 s (backtrack: 1/20).


!!! All ebuilds that could satisfy "sci-libs/udunits" have been masked.
!!! One of the following masked packages is required to complete your request:
- sci-libs/udunits-2.2.28::gentoo (masked by: UCAR-BSD license(s))
A copy of the 'UCAR-BSD' license is located at '/Volumes/Disk 1/Repository/portage-git/licenses/UCAR-BSD'.


(dependency required by "sci-misc/ncview-2.1.8::gentoo" [ebuild])
(dependency required by "=sci-misc/ncview-2.1.8" [argument])
For more information, see the MASKED PACKAGES section in the emerge
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