Rosebury, of Earnshaw Road, admitted three counts of making indecent images of children, possessing extreme images, and possessing a prohibited image of a child.
Det Con Aria Powell, of the online child abuse investigation team, said: “Online offending is not a victimless crime.
“People who view these horrific images are effectively facilitating this type of crime, which affects so many children across the world.
“We have a clear duty to protect members of the public, and especially the most vulnerable, and this sentence should send a clear message to offenders that you will be brought to justice – irrespective of who you are, or your position in society.”
Det Ch Supt Mike Allen, head of GMP’s Professional Standards Directorate, said: “The public rightly expects the highest professional standards from those who serve in the police, and it is clear that the actions of Mark Rosebury fall disgracefully below that.
“He should be appalled by his crimes and the impact his actions understandably have on the public’s confidence in the overwhelming majority of officers who are professional, decent, hard-working people who serve their communities day-in, day-out.
Rosebury remains suspended from the force, and following his imprisonment, his pay has been stopped “with immediate effect”, he said.
He added a misconduct hearing will now be accelerated, since there is no longer a risk to prejudicing criminal proceedings.
