What is the ruling on someone who experiences a wet dream and semen exits during his sleep in the daytime in Ramadan, and water is unavailable for ghusl?

If a fasting person has a wet dream and finds traces of seminal fluid after waking up, ghusl (ritual bath) becomes obligatory upon him. If the time for prayer comes and he does not find water, he should perform tayammum (dry ablution) and pray. He is not required to repeat the prayer when water becomes available.