Depends on many things as to how "efficient" you can get . Here's one possibility:

my @envars;

push @envars,{ value => 23, description => 'temperature in Celsius' },
              { value => 56, description => 'relative humidity in %' }
+,
              { value => 1008.1, description => 'pressure in millibars
+' },
              { value => 4, description => 'dewpoint in degrees Celsiu
+s' },
              { value => 344, description => 'total column ozone in Do
+bson Units' };
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You could do better by not repeating the text "value" and "description" several times.

# say you've got 2 parallel arrays @values and @descriptions
my @envars = map({ value => $values[$_], description => $descriptions[
+$_] }, 0..$#values);
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Or perhaps you really want to just push them onto the array rather than clobbering it each time...

# Same assumption as before ...
for my $i (0..$#values) {
  push @envars, { value => $values[$i], description => $descriptions[$
+i] };
}
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