Snyder is responsible for this scene.
HOWEVER, Whedon is responsible for nearly every other good Superman scene in the movie. Remember, this was supposed to be a two-movie story, and Superman was supposed to turn evil for part of it. Fortunately Whedon realized that people were sick and tired of grumpy, mopey, serial killer Superman and chucked all of that, and gave us happy Clark instead. Shame about the mustache, though.