Same thing I do with mine on my Prelude. If it's cold or there's ice on it, I just push it down or pull it up... which ever it is I want.

Just be careful when pushing it down. Don't just put your hand on the tip and push down... try grabbing in the middle and pulling it down a bit at a time. Don't want the antenna to snapoff or bend by pushing from the top. I only push from the top when there's less than 4 inches to go.

Your location says NYC (assuming New York City) I'm about 2-3 hours west of you... it's facking cold, snowy and icey here... make sure it's not just cold or frozen. No need to replace it if it just needs to thaw.