The top environmental story of 2011 — and probably 2012 too

If you’re wondering what to worry about in the coming year, look no further than the eco-landscape.
Climate change, species extinctions, ocean acidification, forestry losses, soil erosion and air pollution. We humans, now 7 billion strong, are pushing the planet hard, creating a brew of intractable environmental issues that threaten our way of life, and ultimately our survival.
Grim? It doesn’t get much more so.
There were bright moments in 2011. A sampling: