Earth Hour just ended here in Los Angeles. I'll confess I didn't start on time, but once I got my act together, Rob and I walked the dogs and then had a drink on our apartment balcony until it ended. We had a candle lit and I do wonder how much that contributed to global warming.
While walking the dogs, we saw our corner store was open for business, but with the lights off. If I'd had to guess who in the neighborhood would participate, I'd never have picked this store. To me, that's the most encouraging part of this exercise -- finding out people I never thought would care, actually do.
Overall, I didn't notice a big difference in the amount of our neighborhood's light pollution, but here's a couple of pictures of Griffith Park Observatory, with and without lights.