Global ChangeIntersection of Nature and Culture

That’s the conclusion of a new paper by Thomas Dietz and colleagues published this week in the Proceedings of the National Academy of Sciences (open access).Policy measures like cap and trade, they argue, could take years to implement.  Why not take a look at how much readily available technologies in U.S. homes could potentially reduce emission in the short term?

How much of a difference could households make? According to Dietz et al., they are

• 38% of the overall US carbon emissions
• 8% of global emissions
• larger than the emissions of any single country except China

By altering behaviors at home to reduce emissions, they call this kind of rapid response a “behavioral wedge,” analogous to the other kinds of carbon reduction wedges proposed by Pacala and Socolow.

What kinds of reductions are possible?

• They estimate that behavior modifications could save 20% of household emissions in 10 years
• This is 7.4% of the the US emissions
• Interestingly, they ranked these behavior changes by amount of carbon reduced and the ease of which people are willing to change behavior (what they call behavioral plasticity).

Here’s what they found (ranked from highest to lowest behavioral plasticity, with emissions reductions in megatons of carbon in parentheses):

1. weatherization (25.2)
2. HVAC equipment (12.2)
3. low-flow showerheads (1.4)
4. efficient water heaters (6.7)
5. appliances (14.7)
6. low rolling resistance tires (7.4)
7. fuel-efficient vehicle (56.3)
8. change HVAC air filters (8.7)
9. tune up AC (3)
10. routine auto maintenance (8.6)
11. laundry temperature (0.5)
12. water heater temperature (2.9)
13. standby electricity (9.2)
14. thermostat setbacks (10.1)
15. line drying (6)
16. driving behavior (24.1)
17. carpooling and trip chaining (36.1)

Bottom line:

• Upgrading homes is a lot more behaviorally palatable than altering driving habits.
• The good news is that there are some home modifications like weatherization and HVAC equipment that can have a big impact.
• The bad news is that changing to a more fuel-efficient vehicle, altering driving behavior, and carpooling can also have a big impact, but these behaviors are least likely to change.

This paper is a great example of why sociology and psychology are critical to the current conversation on climate change.

photo credit: http://www.flickr.com/photos/caribb/ / CC BY-NC-ND 2.0