He is described as white, about 5ft 10in in height and of medium build.
He has short grey hair, and usually wears jeans, a t-shirt and a zip-up jumper.
‘Concerns are growing for Michael’s welfare’
Officers investigating Mr Irvine’s disappearance are appealing for any one who may know of his whereabouts to come forward.
Sergeant Alexander Brydon said: “Concerns are growing for Michael’s welfare and we would appeal to anyone who may have seen him or has any information on his whereabouts to please contact police.
“Information can be passed to officers via 101 quoting police incident reference 1640 of May 22.”