Who is Lietuenant Commander Roberto Bratt from Ice Hunt and what is their importance?

Roberto's mother is Mexican, and his father is Cuban. He blames his short fuse on the fact that they were both loud and volatile. He is a lieutenant commander and the XO of the Polar Sentinel. Dependable and stalwart, Roberto is the man chosen to go to the Ice Station and clear out all personnel before the Russians arrive. He and Lieutenant Washburn remain behind when they realize some members have not made it to the evacuation point, volunteering to see to their safety until a rescue can be mounted. Bravery and unselfish behavior are attributes they both possess.