Pemberton believes Tomlin, who made six league appearances for Cherries this season, will bring plenty of experience to Ashton Gate with the Robins sitting third bottom on the Championship table.
"We've been monitoring his situation at Bournemouth and it's great that we've been able to bring him on board," Pemberton told the club's official website.
"He wants to play football and he'll bring us ability and experience.
"We've already spoken about the way we want to set the team up with a tighter backline but we can't neglect the fact we need to score goals.
"Hopefully Lee will give us that in the final third. In tight games, like at Leeds on Saturday, hopefully he can be the one to notch something for us."