I would like to more thoroughly investigate the impact I have on the world. This includes determining roughly how my interactions with other people affect their well-being; how much energy is required to sustain my habits (this would be the energy expenditure involved in the transportation, distribution, production, etc... of the goods and services I consume or utilize); and what my carbon/emissions footprint is.

Before I act on this, I would like to further reduce the likelihood that I waste my time doing something intractable or unuseful. So, as a first step, I ask:

What metrics might be useful for measuring an individual's short-term and long-term impact on civilization and the biosphere?

I have already thought about estimating my impact in terms of emissions, energy expenditures, and well-being fluctuations in others, but would like to know if this list should be expanded or pruned.  

While there are more questions I could ask (e.g., how should I proceed in measuring metric x), I think the question I have asked above is a decent first step in this project.

In addition to any answers to this question, a pointer to resources or existing literature on the topic of "human impact quantification" (or an equivalent term) would be highly appreciated.  I do not know if similar projects have been carried out, save for posts similar to Scott Alexander's Carbon Cost Quantified. An interesting prototype question I have thought of for my investigation is: How costly (in terms of energy expenditure or emissions) is it for me to use a single square of toilet paper?.

A tangential question to this one that focuses more on the successful execution of a project on impact quantification might be: What are some products or services that more easily allow one to quantify the impact they make by using them? Any advice (questions or other considerations) of this nature would also be useful to me.