“Fear of flying”
"For those who fly regularly, boarding airplanes for far-flung vacation destinations and distant family gatherings, flights could account for a large and growing share of their carbon footprint. A single round-trip between New York and Los Angeles produces more than half a ton of CO2 per person, or 4 percent of the total amount attributable to a typical U.S. resident in a year. U.S. residents who fly make an average of four round-trip flights each year. Fifteen percent of such people make at least 9 round trips a year."