It is hard to preserve current electronic culture, such as social media. This will be a challenge for cultural historians.

I was immediately struck when I came to Vienna at the degree of energy and material efficiency here. Off the top of my head, i've noticed the following practices:
*escalators slow down when no one is using them
*napkins are not stuffed into bags for you when you get food for take out (you pick them up yourself from the counter
*soda machines have glass bottles, not aluminum cans, and next to the machines are racks to put the empty bottles into afterwards for reuse
*trainstations and other public places don't have maps, flyers, etc. just sitting in containers for people to grab. you have to get them from the ticket window, for example
*doors to trains and trams do not open unless you push a button/pull a lever/etc. i don't know why this is, perhaps to save heating/air conditioning?
*bags at supermarkets need to be purchased, they are not just given to you

Achieving environmental targets, e.g. not exceeding standard concentration of PM2.5, by controlling local sources or domestic (as in a country) is already difficult. Bbut what about the stuffs blown in from other countries? A study using a global 3-D chemistry transport model 'GEOSCHEM' at Harvard Univ. reveals that the US may not be able to attain their air quality level in national parks to the targeted level even if they turn off the whole US emissions because transboundary pollution even far away from China will result in exceeding of the targeted concentration.

Some options to produce biofuels in order to reduce greenhouse gas emissions might affect the albedo, i.e. the reflective properties, of the ground where the biofuel is grown. In the worst case the albedo might be reduced with amounts that offset the benefits from biofuel use. Therefore such effects should be included in future climate policy targets.