The company I work for uses high quality carbon offsets to reach carbon neutrality for all business activities, including business travel by employees. Of course, this isn't scalable, so it doesn't really absolve me. But the travel I do is also not really optional. I just personally don't think it's necessary or helpful. Doesn't mean I don't have to do it when I'm called upon to do so.

The other thing I do is live a fairly carbon efficient lifestyle. I travel much less than other folks in my income bracket, and I live in the most carbon efficient city in the U.S. I take mass transit to work and don't own a car. There is of course more that I could do, but if I zero out my usage it will make precisely no difference to the outcome. So I also vote with my dollars and my actual votes for political candidates who will push in the right direction on this issue.

But more than anything, I think if I'm honest, I don't justify it. I just do it. These scales cannot be balanced -- the human mind cannot encompass actions whose harms are so incrementally minor and diffuse, but corporately so major and severe. Our social heuristic engine is not equipped to process it, and mine isn't an exception.

Thank you for an honest and good answer

Generally speaking, people almost always find some way to justify their actions to themselves, if they even think about what they do in ethical terms at all.

They justify it by convincing themselves their actions are necessary to feed their families, or they think what they do isn't as bad as what someone else does, or everyone else is doing it, or they'll compromise for now but do better later, or they just don't care about most others and are looking out for themselves, their friends and family.