![]() Global warming is the most overwhelming boundary. Currently we lose over 100 species per million per year. ![]() The boundary is 10 species going extinct per million per year. Loss of biodiversity reduces every form of ecological resilience. Drawing on a landmark paper in Nature in 2009 (“ A Safe Operating Space for Humanity,” by Johan Rockström et al.) Lynas outlined the nine boundaries we should stay within, starting with three we’ve already crossed. Some of those global alterations made by humans may be approaching tipping points-thresholds-that could destabilize the whole Earth system. Welcome to the Anthropocene, our very uniquely human geological era.” We’ve raised the temperature of the Earth system, reduced the alkalinity of the oceans, altered the chemistry of the atmosphere, changed the reflectivity of the planet, hugely affected the distribution of freshwater, and killed off many of the species that share the planet with us. In doing this we’ve had to capture between a quarter and a third of the entire photosynthetic production of the planet. In half a million years we’ve gone from prodding anthills with sticks to building a worldwide digital communications network. ![]() ![]() ![]() We’ve made a bit of a comeback since then. We were down to just a thousand or so embattled breeding pairs. “About 74,000 years ago,” Lynas began, “a volcanic event nearly wiped out humanity. ![]()
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