The economists John Kay and Mervyn King assert in their book ‘Radical Uncertainty – decision-making beyond numbers‘ that ‘economic forecasting is necessarily harder than weather forecasting’ because the world of economics is non-stationary whereas the weather is governed by unchanging laws of nature. Kay and King observe that both central banks and meteorological offices have ‘to convey inescapable uncertainty to people who crave unavailable certainty’. In other words, the necessary assumptions and idealisations combined with the inaccuracies of the input data of both economic and meteorological models produce inevitable uncertainty in the predictions. However, people seeking to make decisions based on the predictions want certainty because it is very difficult to make choices when faced with uncertainty – it raises our psychological entropy [see ‘Psychological entropy increased by ineffective leaders‘ on February 10th, 2021]. Engineers face similar difficulties providing systems with inescapable uncertainties to people desiring unavailable certainty in terms of the reliability. The second law of thermodynamics ensures that perfection is unattainable [see ‘Impossible perfection‘ on June 5th, 2013] and there will always be flaws of some description present in a system [see ‘Scattering electrons reveal dislocations in material structure‘ on November 11th, 2020]. Of course, we can expend more resources to eliminate flaws and increase the reliability of a system but the second law will always limit our success. Consequently, to finish where I started with a quote from Kay and King, ‘certainty is unattainable and the price of near-certainty unaffordable’ in both economics and engineering.
The latest UN Climate Change Conference in Madrid, which is holding its closing session as I am writing this post, does not appear to have reached any significant conclusions. Unsurprisingly, vested interests have dominated and there is little agreement on a plan of action to slow down climate change or to mitigate its impact. However, perhaps there is progress because two recent polls imply that 75% of Americans believe humans cause climate change and roughly half say that urgent action is needed. This is important because the USA has made the largest cumulative contribution to greenhouse gas emissions with 25% of total emissions, followed by the EU-28 at 22% and China at 13%, according to the Our World in Data website. However, the need for urgent action is being undermined by suggestions that we cannot afford it, or that we will have better technology in the future that will make it easier to act. However, much of the engineering technology that is needed to remove fossil fuels from our economy is already available. Of course, the technology will be improved in the future but that is always true because we are continually making technological advances. We could replace fossil fuels as the energy source for all of our electricity, buildings and heating (31%) and for most of our industry (21%) and transportation (14%) using the technology that is available today and this could eliminate about two-thirds of current global greenhouse gas emissions. The numbers in parentheses are the percentage contributions to global greenhouse gas emissions according to the IPCC. Of course, it would require a massive programme of infrastructure investment; however, if we are serious then the subsidies paid to the oil and gas industry could be redirected toward decarbonising our economies. According to the IMF, that is approximately $5.2 trillion per year in subsidies, which is about the GDP of Japan. The science of climate change is well-understood (see for example ‘What happens to emitted carbon‘ and ‘Carbon emissions and surface warming‘) and widely recognised; the engineering technology to mitigate both climate change and its impacts is largely understood and implementation-ready; however, most urgently, we need well-informed public debate about the economic changes required to decarbonise our society.
Footnote: The videos ‘What happens to emitted carbon‘ and ‘Carbon emissions and surface warming‘ are part of a series produced by my colleague, Professor Ric Williams at the University of Liverpool. He has produced a third one: ‘Paris or Bust‘.
Last week in Liverpool, we hosted a series of symposia for participants in a dual PhD programme involving the University of Liverpool and National Tsing Hua University, in Taiwan, that has been operating for nearly a decade. On the first day, we brought together about dozen staff from each university, who had not met before, and asked them to present overviews of their research and explore possible collaborations using as a theme: UN Sustainable Development Goal No.11: Sustainable Cities and Communities. The expertise of the group included biology, computer science, chemistry, economics, engineering, materials science and physics; so, we had wide-ranging discussions. On the second and third day, we connected a classroom on each campus using a video conferencing system and the two dozen PhD students in the dual programme presented updates on their research from whichever campus they are currently resident. Each student has a supervisor in each university and divides their time between the two universities exploiting the expertise and facilities in the two institutions.
The range of topics covered in the student presentations was probably even wider than on the first day; extending from deep neural networks, through nuclear reactor technology, battery design and three-dimensional cell culturing to policy impacts on households. One student spoke about the beauty of mathematical equations she is working on that describe the propagation of waves in lattice structures; while, another told us about his investigation of the causes of declining fertility rates across the world. Data from the UN DESA Population Division show that live births per woman in the Americas & Europe have already fallen below the 2.1 required to sustain the population, while it is projected to fall below this level in south-east Asia within the next five years and in the world by 2060. This made me think that perhaps the Gaia principle, proposed by James Lovelock, is operating and that human population is self-regulating as it interacts with constraints imposed by the Earth though perhaps not in a fashion originally envisaged.