Ho Štěpán, this is a challenging question. I'm working on answering it for
you. So far I can tell you that a) both sentences have exactly the same
meaning. B) in these one sentence ‘there’ is functioning as a pronoun. C)
the second sentence is called an expletive sentence and is thought to be poor
English in some circles (though not by me!) I suppose you already know this
though and want to clarify the term semantically empty. I'll be back shortly to
try to answer that. By the way it's also common in English to use both there at
the start as a pronoun and again at the end as a place eg. There were a lot of
children there.
Ok I'm back. I'd say yes. It can be called a dummy pronoun without explicit
meaning. Let me know if you want links to more info.