Traveling is one of my most challenging carbon footprint costs, as I travel a lot for my work. Ironically, it is frequently for sustainability conferences. I try to compare my footprint to my handprint. If the trip has a greater benefit from meeting face-to-face than remotely and I can buy carbon off-sets then I am able to justify the trip. Otherwise, I do my best to plan webinars and on-line meetings to cut down on trips.
One more complication is that my partner was transferred to Hawaii, so this has added a couple of flights onto our life now. I am striving to at least combine trips, with open jaw flights, via Honolulu now, so I can cut down on some roundtrips to Portland.