Desde hace makes the most sense. The best form for this sentence is, "Te espere` una hora." It's shorter and direct.
Los Angeles, California, shortened from original Spanish name was once <span>El Pueblo de Nuestra Señora la Reina de los Ángeles del Río de Porciúncula.</span>
Wrong subject, lol. But I would infer that the rates of evaporation is higher since the more evaporation there is then the more substances are left behind by the ocean water. (In other words, salt)