Oily water covered a five-mile stretch of beach on Perdido Key, Florida over the weekend, just two weeks after Hurricane Sally hit the area. US coast guard officials are in the process of determining the source of the oil, which Escambia County Administrator Janice Gilley said resembled the tarballs from the 2010 Deepwater Horizon oil spill. Climate change, caused by burning fossil fuels, increases air and ocean temperatures and has wide-ranging effects on hurricane intensity. Warmer temperatures increase the rate of water evaporation from land and sea surfaces, which feeds moisture and energy into storms. (USA TodayWKRGHuffPost; Climate Signals background: Hurricanes)