Malcolm Gladwell (The Tipping Point: How Little Things Can Make a Big Difference – Little Brown – 2000) defines a Tipping Point as, “the moment of critical mass, the threshold, the boiling point.” Since Gladwell’s publication, the term has been “adopted” in various disciplines, some of which have applied more quantitative descriptions. The Tipping Point term plays an important role in Climate Change (see my June 25, 2012 blog), forming a set of markers to hopefully help us make changes, before we reach the point of no return that we are all trying to avoid. In a recent survey in Science magazine (Marten Scheffer et al. (11 co-authors) – Science – 19 October 2012, Vol 338, p. 344), Tipping Point was defined as a “Catastrophic Bifurcation,” a term which was taken from mathematical Chaos Theory, and has its own well developed definition. Bifurcation indicates a splitting into two branches; the “fork” in the title of both my book and this blog refers to the same phenomenon. Tipping Points are predictable, an aspect that attracts a great deal of interest for obvious reasons. The financial markets have seen intense activity in this area (see James Owen Weatherall’s The Physics of Wall Street, Houghton Mifflin Harcourt, 2013), with attempts to predict upcoming financial bubbles. The main premise behind the ability to predict bifurcation is that one monitors the driving forces that tend to restore a system to its state of equilibrium. As the system approaches the tipping points, these restoring forces tend to decrease until they completely disappear.
Last week, Jim Hansen announced that he is retiring (he is 72) from NASA to continue pursuing political and legal efforts to limit greenhouse gases. His retirement has attracted widespread attention (Justin Gillis – New York Times – 4/02/2013). Hansen has been known for both his scientific work and his efforts to bring public attention to the inherent dangers of humanity’s current effects on changing the physical environment. He has focused primarily on climate change in both of these settings. Hansen has been the head of NASA’s Goddard Institute of Space Studies (GISS) since 1981. In this capacity, he pioneered both the measurement of the Global Mean Temperature and the development of the General Circulation Model. These allowed for comparison between predictions and experiments, aiding in projecting the future under various scenarios. Hansen was shocked by what he saw, and gave his testimony before a congressional committee in 1988 to warn the rest of the world. That same year, the Intergovernmental Panel on Climate Change (IPCC) was established by two United Nation organizations: the World Meteorological Organization (WMO) and the United Nation Environmental Program (UNEP). The IPCC published its first official assessment report in 1990. It then convened at the Earth Summit in Rio de Janeiro in June of 1992 to establish the United Nations Framework Convention on Climate Change (UNFCCC). This served as the precedent for the beginning of the Kyoto Protocol, whose implementation and progress have now more or less stalled.
Throughout this time Hansen was wearing two hats simultaneously: that of the “objective” scientist, whose work was scrutinized and refereed by the scientific community, and that of a “Cassandra,” warning us of the consequences of our current actions. NASA administrators and many scientists criticized him for his dual role (see my May 7, 2012 blog). Some in NASA have argued that NASA should not involve itself in trying to predict the future, worrying that any mispredictions might lead to a loss of credibility for the agency. Opponents claim that his science is colored by a political agenda. He was, however, one of the first to fully realize that with upwards of 7 billion people, each striving for a better standard of life, the future of science and political activities cannot remain separate. We are now part of the physical system. We are part of science. I often use one of the most important principles in science, called Le-Chatelier’s Principle, that states:
Any system in chemical equilibrium, as a result in the variation in one of the factors determining the equilibrium, undergoes a change such that, if this change had occurred by itself, it would have introduced a variation of the factor considered in the opposite direction.
The equilibrium between humans and the physical environment is now being disturbed, and one possible way the system could restore its own equilibrium would be to wipe us from the face of the Earth.
In this sense, “objective” scientists must become more like physicians. It is not enough to investigate the patient’s symptoms; we have to find out what went wrong and how to cure it. The “patient” in this case is the planet and Jim Hansen is trying with all his might to cure it. The political process is part of that cure. He is one of the earliest “scientist – healers,” and I wish him the best in all his endeavors.