How can i get my cat to stop meowing so much?

i have a black and white domestic short hair cat (dont know what hes mixed with) but he is a indoor /outdoor cat and he crys SO loud and SO much when he wants to go out even at night. about a year ago he cryed but NEAR as bad as he does now and its soo annoying. he crys like hes dying or something just to go out and he does the same loud obnoxious crying to come in to so is there a way to tone his meowing down? it so obnoxious and loud i just dont even want to let him back in.