In the quest for Five Percent for Footprint (FPF, like SPF just for the plane), it you are going to cut out 1 in 20 days of commuting to work, the simplest is to telecommute. No funky schedules, no readjusting your travel pattern. Instead of going to your car to drive to work, walk over to a place in your home that is free of noise and distraction. You may need to make sure your kids, S.O. and others understand that you are working, not just loafing at home.
Another dependency is that your works lends itself to working remotely, you may need to figure out how to connect to the office. It's important when working remotely that people get a sense that, well you're working. So talk with your boss about ways to schedule.
One way to make telecommuting work is to schedule your FPF day as a research day, or a day that your write those extended memos that need silence. The lack of someone popping into your cube at random times (Guilty!) breaking your hard earned train of thought.
This is the by far the simplest way to get back some time. Depending on your commute you'll realize how draining the commute can be. On the flip side, you need to be prepared if that was your alone time to decompress. In that case, take a walk after your work at home day and help both your's and the planet's health.