Somebody who wants to reduce his "carbon footprint" can bicycle to work, never buy aerosols and turn off his air-conditioner-and still blow away all this virtue on a couple of long flights.

Somebody who wants to reduce his "carbon footprint" can bicycle to work, never buy aerosols and turn off his air-conditioner—and still blow away all this virtue on a couple of long flights.

Increasing or decreasing respiration - When you breathe more rapidly, you blow out more carbon dioxide.