You'll want to take a look at eval...

eval {
  @time_arr    = split(/-/,$components[1]);
  $time_arr[1] = $time_arr[1] -1;
  $unix_time   = timelocal(0,0,0,@time_arr[2,1,0]);
};

if ( $@ ) {
    # propagate unknown errors
  die $@ unless $@ =~ /out of range/;
}

# ... script continues
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    --k.