The Great Barrier is shaped like a giant dome, where inside a giant mist has formed.
"Shield" and Relevance.[]
The anime show explains at the beginning how the president has taken "emergency measures," which were not elaborated on until episode 2.
Functionality[]
Further elaboration in episode 9 shows that a C-17 aircraft was able to fly through the barrier unharmed due to unnatural works surrounding the 'Fog.' However, the giant tentacle effect is not explained thus far in the series.
