a quest for: Knowledge .......................................................................................................... A good starting place for a quest for knowledge is an understanding of one's ignorance.
Ballocks to that. It's your data, you have the responsibility to show us where you get it from. Just give us the links. You must have them. If you don't, we will think you are like Magical Realist, who tries things on as serious, and then pretends it was all a joke and dissociates himself from it when exposed.
So why post a vaguely based per capita chart, to make a point about total effect? And why post now about percentage increases, if your point is about total effect? There's a book written about this kind of employment of percentages and poorly defined populations and so forth. The title of the book is "How To Lie With Statistics".
The charts were just broad strokes indicating trend-----as pointed out, they did not agree with each other 100%. The mentioned percentage increases are pertinent to mitigation..........I doubt that you and I will agree on the finer points of the value of most efforts of mitigation. (as an aside I would rather invest in remediation)----Planting trees, I suppose could be seen as both mitigation and remediation? Anyway, the point wasn't the particular details nor methodology behind the posted studies, it was more of an answer to the question posed in the beginning of this thread "How can I help to reduce global warming" (one answer = Don't fly. Not all can follow my path, nor would want to. I like trees and shade, I have the acreage, so planting them was a win for me and a win for the environment. And, I do not like to travel---so that part is also easy. There are myriad things that we all can do---don't use air conditioning, put on an extra layer of clothing in the winter, curtail unnecessary travel, by locally grown food, .......etc.....etc... If you find just one that you like you become less of the problem, and more of the solution. and 2 would be better. cool?
Grok'd! - To Wit : "there are three kinds of falsehoods, lies, damned lies and statistics" - Arthur James Balfour, 1st Earl of Balfour, as quoted in the Manchester Guardian, 29th June 1892: "Professor [Joseph] Munro reminded him of an old saying which he rather reluctantly proposed, in that company, to repeat. It was to the effect that there were three gradations of inveracity - there were lies, there were d-d lies, and there were statistics." - http://www.phrases.org.uk/meanings/lies-damned-lies-and-statistics.html
a finer point Aviation makes a significant contribution to anthropogenic climate forcing. The impacts arise from emissions of greenhouse gases, aerosols and nitrogen oxides, and from changes in cloudiness in the upper troposphere. An important but poorly understood component of this forcing is caused by ‘contrail cirrus’—a type of cloud that consist of young line-shaped contrails and the older irregularly shaped contrails that arise from them. Here we use a global climate model that captures the whole life cycle of these man-made clouds to simulate their global coverage, as well as the changes in natural cloudiness that they induce. We show that the radiative forcing associated with contrail cirrus as a whole is about nine times larger than that from line-shaped contrails alone. We also find that contrail cirrus cause a significant decrease in natural cloudiness, which partly offsets their warming effect. Nevertheless, net radiative forcing due to contrail cirrus remains the largest single radiative-forcing component associated with aviation. http://www.nature.com/nclimate/journal/v1/n1/full/nclimate1068.html
Kind of off topic, but speaking of contrails.. I came across an article a few days ago about a couple who are "chemtrail" nuts. She quit her six figure job as a software developer to become an organic farmer.. Anyway, her and her husband are both convinced that all of the airplanes flying around are full of some chemical mixture that they are spraying in the atmosphere. She was asked where she first came across this. Guess what she said... Facebook. She was convinced of the chemtrail conspiracy through Facebook groups. Think of how many people are being convinced of equally ludicrous bs, like climate change being a hoax, through friggin Facebook...