A very, very preliminary outline. Basically a starting point, without much of an end.

>> Preface: The anthropocene. Needs to be the context here — that humanity is now capable of putting stresses on the planet at a scale once reserved for meteors, solar activity, and so on. This isn’t just about climate: every aspect of the planet’s biosphere, from the composition of its atmosphere to pollutants in water to where water goes to what physically covers entire continents, is determined by us.

>> Introduction to tipping. An easy-to-grasp scene where tipping takes place. Maybe Aaron Ellison and his pitcher plant research? The dynamics of tipping, as seen in an ecosystem contained in a thimbleful of water … and Aaron can connect up to larger tipping questions/scales.

>> History: the first environmental tipping research. It used to be thought that environmental changes followed nice, easy, essentially linear progressions. Whatever happens, it’s a shift in degree along a straightforward scale. But this doesn’t appear to be the case. Early research that showed otherwise: on the dynamics of spruce budworm infestations in Maine. (The researchers still alive now; old, living across the street from each other …  good scene?)

Their work draws on Nobel prize-winning math used to describe non-linear physical systems: fluid turbulence, the magnetizing of metals, and so on. Maybe dig in here on the dynamics of tipping, what this nebulous term actually means?

>> Environmental tipping research expands. There are several key ecosystems in which the foundations of ecological critical transition research were laid. First is the arid band across Africa: about 5,500 years ago, the Sahara underwent a radical shift from lush grasslands to desert. For decades this baffled scientists. It only made sense when they started using models that incorporated critical transition dynamics.

Arid grasslands remain a mainstay of critical transition research — will come back to them later in the book, when talking about research applications. Two more important systems are freshwater lakes as they become eutrophic — a very dramatic change, and one that’s relatively easy to study — and coral reefs, which have tremendous ecological significance and are also easy to study. The late-20th century collapse of corals in the Bahamas are a very instructive example.

Should arid grasslands get there own chapter here, clearly demarcated from the underwater stuff? Or should this chapter be about the emergence of the research, and segue naturally into ….

>> Tipping that’s already happened. In the Mediterranean (and perhaps the North Sea, Black Sea, and other mid-sized bodies of water.) The Mediterranean transition is especially poignant: its waters have historical resonance, with fishing records stretching back to the time of Aristotle … and giant swaths of its most-productive regions have essentially gone from underwater jungles to underwater deserts. It’s that dramatic. Where once there were rich webs of life, there are now minnows, invertebrate animals and bacteria.

>> Tipping in the rainforest. Following that example of the underwater jungles, how about the above-ground jungles, the so-called lungs of the world? Some absolutely fascinating research going on in the Amazon, and also in Borneo and Malaysia. There’s a tendency to think of deforestation as something you can just stop, and the forest will grow back. But it might not be like that: enough deforestation can trigger changes that will so radically change the environment that it’s impossible for the forest to ever grow back. The new condition is probably savannah.

The rainforest-to-savannah possibility would make for a perfect segue into an Earth-wide tip, and what that would mean. However, there are still a few….

>> Things that haven’t fit in neatly so far. Until now, I’ve been talking about specific regions. Within those regions, combinations of factors — say, overfishing and pollution — have an effect. But some things are a bit harder to quantify just yet. What is the effect of, say, losing a tenth of the world’s species? We just don’t know, and this isn’t region-specific. Same goes, perhaps, for the plastic content of Earth’s oceans, the amount of fresh water we use, the total amount of nitrogen pollution and land use.

These factors were among those discussed in the landmark Nature paper from September 2009: the attempt to sketch out a “safe operating space” for humanity, putting planet-wide numbers on seven stresses (the others were carbon dioxide pollution, ocean acidification, phosphorus pollution.) At least one, if not more, of these deserves their own chapter — I’m leaning towards fresh water use and plastics, because they’ve received less attention than these other stresses, and are so dramatic.

And hopefully these planet-wide rather than region-wide chapters will lend themselves to….

>> Could Earth tip? And if so, what’s it going to look like? This is tough, because the science at this level is so speculative. But it should come together as the reporting does. Ostensibly lots of great … um … computing scenes.

>> Practical applications. Some of the early pioneers in transition research are now applying the findings to managing grasslands in Australia. Some of the newcomers, who have been running a long-term research site in New Mexico, are instituting a program in Mongolia. (Mongolia sounds like a possible chapter unto itself … scientists say the grasslands can handle 18 million cattle, the government says 100 million; a microcosm of our demands on the Earth.) They’re trying to look for physical patterns that hint at am impending shift — telltale changes in the geometries of vegetation, as seen from above, or else measured at ground level. (Maybe the grasslands/early warning stuff should go earlier, between the “research expands” chapter — which focuses on grasslands — and “tipping that’s already happened”?

Trying to find early warning signs of tipping points is fantastically important. But what if it’s not always possible? The best thing to do is use precautionary common sense. But how do you do so at a planetary level?

Image: Invoking the power of the IBM Selectric, courtesy of Marc Smith