We come now to the time that humanity lives on earth. We have seen that Nature has developed two tendencies from the beginning. The first is the development of awareness or “mind”, present even in the very first self-generating metabolism. This awareness has clearly been a valuable trait, and it has been selected for and refined since the beginning of life. The second tendency is toward cooperation. We have followed this from even before the dawn of life, and have watched the growth, refinement and complexity of successive stages of the cooperative entity of life and the levels that it is composed of. These levels can be thought of as a set of nested Russian dolls, from complex molecule, up through complex ecosystems. Humans, whales and dolphins seem to be the most aware and cooperatively functioning of the multicellular beings so far brought forth within this cooperative system.
But what of the entity of all life? If it is cooperative entity then, like the most primitive bacterium, it has mind. Some ability to decide about its internal regulation and its inputs and outputs are implied as a function of its identity. Does Earth have identity?
Our ability to communicate with this entity is not guaranteed, as we ourselves would not expect to communicate with a single cell in one of our bodies. It would be very useful, in our current situation, to be able to talk to Nature, but rational approaches do not make much sense in this pursuit. Some cultures have developed awareness of Earth, but with different faculties then the rational.
Tipping points in complex systems are situations where the system either converts suddenly to a different state, or where runaway positive feedback threatens the whole system. These points can be envisioned in a complex system, but not predicted with precision with any computer working today. Several potentially catastrophic tipping points in the Earth system are being monitored today.
The northern jet stream seems to depend on a large temperature difference between the mid-latitudes and the poles. The polar regions have warmed much faster in the last few decades than the mid-latitudes, and the jet stream has become slower and much more wavy. The jet stream appears to be in transition, but we cannot predict what the next steady state of this system will be.
The North Atlantic Conveyor, that includes the Gulf Stream, shut down at the end of the last glaciation and caused an 1100 year return to the Ice Age in northern Europe. There are signs that this may be another tipping point: a similar shutdown of the North Atlantic Conveyor could happen in the near future.
Methane is much stronger as a greenhouse gas than CO2. There are large stores of methane in shallow sediments in the Arctic Ocean and in the permafrost of northern climates. Rising temperatures have begun releasing this methane, and there could be a tipping point into a positive feedback loop where massive amounts of methane could be released suddenly. Current computer models and other rational analysis are not yet powerful enough to predict any of the above situations.