Breakdown of È molto probabile che il ghiacciaio si scioglierà.
essere
to be
molto
very
che
that (conjunction introducing a clause)
probabile
probable
Questions & Answers about È molto probabile che il ghiacciaio si scioglierà.
Since è molto probabile che expresses probability, why doesn't it trigger the subjunctive here?
You are exactly right that è molto probabile che usually requires the subjunctive. However, this sentence is talking about an event that will happen in the future. Because modern Italian does not have a future subjunctive tense, it uses the regular future indicative (si scioglierà) to show that the action takes place after the main clause.
Could I use the present subjunctive here instead?
Why is it si scioglierà (reflexive) and not just scioglierà?
The verb here is sciogliersi (to melt / to thaw). Italian uses the reflexive form when a subject changes its own physical state without a direct outside actor. If you used the non-reflexive sciogliere, it would mean to melt something else, and you would need a direct object, like in Il sole scioglierà il ghiacciaio (The sun will melt the glacier).
How would I say this if the main clause was in the past, like 'It was very probable...'?