Any of the commercial rubber roof cleaners (Protect-All)will remove most of the streaks if you spray it on after wetting the roof area with water ... let sit a bit ... scrub with a soft bristled brush ... repeat as needed. Once you get the streaks removed to your satisfaction, apply Aerospace 303 a couple of times a year. The streaks will be fewer and easier to remove. Yeah ... for those of you who think I'm daft and don't realize you can't see the streaks from the ground ... I know they are there and truckers know it too.