Spray a cold 13x9x2-inch baking pan with nonstick cooking spray. Place popcorn in the baking pan.
In a small mixing bowl stir together sugar, water, cinnamon, nutmeg, and ginger. Add spice mixture to popcorn in baking pan. Toss popcorn until coated. Bake in a 350 degree F oven for 15 minutes, stirring once or twice.
Transfer popcorn from baking pan to a large piece of foil. Cool popcorn completely. If desired, store in a tightly covered container up to 3 days. Makes 6 (3/4-cup) servings.