Is a coconut an isolated thermodynamic system? This is a question that I have been thinking about this week. A coconut appears to be impermeable to matter since its milk does not leak out and it might be insulated against heat transfer because its husk is used for insulation in some building products. If you are wondering why I am pondering such matters, then it is because, once again, I am teaching thermodynamics to our first year students (see ‘Pluralistic Ignorance‘ on May 1st, 2019). It is a class of more than 200 students and I am using a blended learning environment (post on 14th November 2018) that combines lectures with the units of the massive open online course (MOOC) that I developed some years ago (see ‘Engaging learners on-line‘ on May 25th, 2016). However, before devotees of MOOCs get excited, I should add that the online course is neither massive nor open because we have restricted it to our university students. In my first lecture, I talked about the concept of defining the system of interest for thermodynamic analysis by drawing boundaries (see ‘Drawing boundaries‘ on December 19th, 2012). The choice of the system boundary has a strong influence on the answers we will obtain and the simplicity of the analysis we will need to perform. For instance, drawing the system boundary around an electric car makes it appear carbon neutral and very efficient but including the fossil fuel power station that provides the electricity reveals substantial carbon emissions and significant reductions in efficiency. I also talked about different types of system, for example: open systems across whose boundaries both matter and energy can move; closed systems that do not allow matter to flow across their boundaries but allow energy transfers; and, isolated systems that do not permit energy or matter to transfer across their boundaries. It is difficult to identify closed systems in nature (see ‘Revisiting closed systems in nature‘ on October 5th, 2016); and so, once again I asked the students to suggest candidates but then I started to think about examples of isolated systems. I suspect that completely isolated systems do not exist; however, some systems can be approximated to the concept and considering them to be so, simplifies their analysis. However, I am happy to be corrected if anyone can think of one!
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.
I had slightly surreal time last week. I visited the USA to attend a review of a research programme sponsored by the US Government and reported on two of our research projects. When I arrived in the USA on Monday evening, I went to collect my rental car and was told that I had been upgraded to a pick-up truck because the rental company did not have left any of the compact cars that had been booked for me. I gingerly manoeuvred the massive vehicle, a Toyota Tacoma, out of the parking garage and on to the freeway. I should admit to having owned a large SUV when we lived in the USA and so driving along the freeway was not a totally new experience, except that the white bonnet in front of me seemed huge.
The following morning, I drove to the location of the review and strategically selected a parking space with empty spaces all around it so that I could drive through into the space and avoid needing to reverse the behemoth. As I was walking across the parking lot, someone accosted me and said: ‘Nice truck, how do you like it?’ Embarrassed at driving such an environmental-unfriendly vehicle, I responded that it was a rental car that I just picked up. To which he replied that the best protection against my Tacoma, was his Tacoma. And, that it was his dream car. Then, I noticed that he had parked his black one alongside mine.
Our children learnt to drive in our ancient Ford Explorer and loved it. We all knew that it was wrong to drive something that consumed fuel so voraciously even if it did get us effortlessly through the most horrendous winter storms. However, we have left all that behind and now either use public transport or drive cars that achieve 60 mpg or more on good days. But here I was being admitted to a club that worshipped their pick-up trucks.
We walked together into the review which was held in a small lecture theatre equipped with comfortable armchairs, which was just as well because we sat there from 8.30 to 4.30 for two days listening to half-hour presentations with only short breaks. We were presented with some stunning research based on brilliant innovative thinking, such as materials that can undergo 90% deformation and fully recover their shape and how the rippling motion of covert feathers on a bird’s wings could help us design more efficient aeroplanes. More on that in later posts. Of course, there were some less good presentations that had many us reaching for our mobile phones to catch up on the endless flow of email [see: ‘Compelling Presentations‘ on March 21st, 2018). At the end of each day, we dispersed to different hotels scattered across town in our rental cars. On Thursday, I drove back to the airport and topped up the fuel tank before returning my truck. I worked out that it had achieved only 19 mpg (US) or 23 mpg (UK), despite my gentle driving – that’s almost three times the consumption of my own car! On the plane home I started reading ‘Overstory‘ by Richard Powers, a novel about our relationship to trees and the damage we are doing to the environment on which trees, and us, are dependent.
This week’s lecture in my thermodynamics course for first-year undergraduate students was about thermodynamic systems and the energy flows in and out of them. I concluded the lecture by talking about our planet as a thermodynamic system using the classic schematic in the thumbnail [see ‘Ample sufficiency of solar energy‘ on October 25th, 2017 for more discussion on this schematic]. This is usually a popular lecture but this year it had particular resonance because of the widely publicised strikes by students for action on climate change. I have called before for individuals to take responsibility given the intransigence of governments [see ‘Are we all free riders‘ on June 6th, 2016 or ‘New Year Resolution‘ on December 31st, 2014]; so, it is good to see young people making their views and feelings known.
Weather-related events, such as widespread flooding and fires, are reported so frequently in the media that perhaps we have started to ignore them as portents of climate change. For me, three headlines events have reinforced the gravity of the situation:
The publication earlier this month of a joint report by UNICEF and the Royal College of Paediatrics and Child Health that air pollution in the UK so high that it is infringing the fundamental rights of children to grow up in a clean and safe environment; and, under the Government’s current plans, air pollution in the UK is expected to remain at dangerous levels for at least another 10 years.
I apologise for my UK focus this week but whereever you are reading this blog you could probably find similar headlines in your region. For instance, the 2016 UNICEF report states that one in seven children worldwide live in toxic air and air pollution is a major contributing factor in the deaths of around 600,000 children under five every year. These three headlines illustrate that there is a planetary emergency because climate change is rapidly and radically altering the ecosystem with likely dire consequences for all living things; that despite a near-existential threat to the next generation as a consequence of air pollution most governments are effectively doing nothing; and that in the UK we are locked into a fossil-fuel dependency for the foreseeable future due to a lack of competent planning and commitment from the government which will compound the air pollution and climate change problems.
Our politicians need to stop arguing about borders and starting worrying about the whole planet. We are all in this together and no man-made border will protect us from the impact of making the planet a hostile environment for life.