"Are you aware that..." means "do you know that..."
The word "aware" is more formal than "know".
People often talk about "being aware" of social issues such as poverty, sexual abuse, pollution, and other problems. Organizations that deal with these issues try to make people aware of them. The organizations hope that once people become aware that there is a problem, they'll work to try to fix it. Here are some useful phrases that you may hear which are related to "awareness":
We're promoting awareness of child obesity.
Our goal for now is just to raise awareness of the problem.