It depends on how it is fastened. It may be glued to the wall in back or screwed and glued through the top and into the bottom of the splash. No matter how it is attached if you will be re-doing the area then the best way to take it off is by looking undeneath to see if there are in fact any screws. If so, remove them from the bottom and then pry the splash away from the wall carefully....Mark Hammond

If it is primarily attached with glue, most glues are thermoplastic, meaning that heat from a heat gun or a hair dryer will soften them to some degree.