Mix ginger ale and water in a saucepan, and bring to a boil. Reduce heat to a simmer; stir in lemon juice, 1 tablespoon lemon zest, raspberries, and sliced ginger. Bring to a boil, and cook over medium heat for 30 minutes, stirring occasionally. Strain the sauce through a fine strainer into a clean saucepan; discard solids. Stir sugar into strained sauce, bring to a boil over medium heat, reduce heat, and simmer until the sauce has thickened, about 10 minutes. Remove from heat, and allow to cool while you prepare the salmon.
Preheat oven to 400 degrees F (200 degrees C).
Coat salmon fillets with olive oil; sprinkle with sea salt, black pepper, and 1 tablespoon of lemon zest. Place salmon fillets into a broiler-proof baking dish. Brush salmon fillets generously with raspberry sauce.
Bake in the preheated oven until salmon is almost opaque in the center and the fish flakes easily, about 10 minutes. Turn on the oven's broiler, and broil the fillets until browned, 2 to 3 minutes. Serve with extra sauce if desired.
