Sentences with "nonreferential it" and "nonreferential there" fall into several categories. The one that applies best to your sample sentence is the so-called "existential" category of sentences that use "nonreferential there." So, for example:
There is a God.
There is a Santa Claus.
There is a contrast between the two brothers.
Another category of nonreferential there's is "locative":
There are several books on the table.
There used to be a tree behind the garage.