Environmental dangers are often described in terms of tipping points—a maximum greenhouse gas level, the total human population our planet can support, or the increase in temperature triggering a large rise in sea levels. As much as we hear about tipping points for environmental disasters, the concept itself is benign: a mathematical threshold in a small value that, when crossed, leads to a large change in something else. Examples of statistics at the tipping point are all around us, and all of us can participate in making a difference for good.
