Showing the human cost is important. When people hear about ice-caps melting, foreign animals becoming extinct, etc, it is not very relevant and they can pretend it is not so important. If you show them people becoming homeless, or a rise in disease because of the climate changing, it becomes more relevant.
The other problem is that many people in the UK resent being told to be environmentally friendly, because large industries are the main polluters.
- Freight is predominantly transported by lorry because it is cheaper than using railways or waterways.
- Heavy industries are expected to cut their emissions, but often avoid it, either by claiming that it would put them out of business, or by storing gas until it is hazardous and then venting it (which is acceptable under Health and Safety regulations - I used to work at a Steelworks who did this).
- The government will not make existing power stations and the grid more efficient (e.g. by using CHP systems), preferring to open new Nuclear Power stations instead. They also never made a real committment to alternative energy sources, claiming it would never be viable to rely on them. Research into wind and tidal energy seems to be proving them wrong...
- Where wind farms and rubbish/biomass incinerators have been built, local people have complained bitterly about the noise and the view. People want energy, but they do not want it to be produced on their doorstep!
- People are told not to waste water: there are often hose-pipe bans, and even a campaign to turn the tap off while we brush our teeth (!!!) Yet the water companies waste huge volumes of water in silted-up reservoirs and leaking pipework that they do not replace.
- Worst of all, councils make money by selling our recyclable materials, but charge higher council tax for collecting it AND they are planning to fine people who do not sort their recycling correctly!
People don't see any point in being environmentally friendly when the government and industry don't bother.
I agree with you making the movie, I am just playing Devil's advocate ;-)
One idea that worked quite well was a BBC series called "When The Lights Go Out" - about a future where there is no electricity or gas. It played on the audience's natural fear of the dark, and Britain's memories of blackouts and rationing in the 2nd World War. The point was made that society would descend into chaos because we are so used to cheap energy - there would be little food in the shops, it would be cold, you cannot drive to a hospital, people would turn to crime... That's the sort of thing I mean about making it relevant to people.
Sorry about the rambling email - if you're interested I could find some references for the above points.