- Emerging infectious diseases
- Sustainable cities
- Moving towards low carbon energy
- The future of the oceans
I attended the talks on low carbon energy and presented a poster in this area. As I am currently working in that field, I have summarised some of the interesting findings from the talks and discussions I had with other delegates during the week.
The conference-defining image
This graph seemed to be on everybody's opening slides. It was first shown by Sir David King (a celebrated chemist with huge involvement in climate change research and policy) during his opening speech. It shows various simulations of where our emissions levels could end up, depending on a representative concentration pathway (RCPs). The different pathways show a number of radiative forcing values by 2100 compared with preindustrial levels (+2.6, +4.5, +6.0, and +8.5 W/m2). These different pathways lead to a range of different expected temperatures, from 0.9 to 5.4 °C increase. We need to be on RCP 2.6 or lower to give a temperature rise of under 2.3 °C.
Here are some of the graph's more important aspects:
- We are currently on track for the worst case scenario, RCP8.5. This will lead to famines, flooding and crop failure.
- The scenario we are aiming for (and that which the Paris agreement set) is RCP2.6. This requires not only complete reduction of CO2 production but actively removing carbon from the atmosphere.
- There is some uncertainty in the simulations as can be seen from the many light-coloured lines but within this error limit, the results all point to serious warming.
You are probably already familiar with this depressing outline of global warming. In the following sections, I will outline how scientists and policy makers are planning to tackle the problem.
Hope for a carbon negative future
Much of the conference discussion was focused on which technologies could make up for the shortfall of energy as we decarbonise our energy production.
Everyone is banking on solar
Professor Martin Green is an Australian expert in silicon solar cells whose group holds the record for the most efficient solar cell (at 25%, up from 11% efficiency in the 1970s). He spoke about the many countries banking on solar energy to replace fossil fuels. The graph below shows the projected chunk of energy that solar is predicted to supply, according to the German Advisory Council on Global Change.
Professor Green spoke about how the price of solar cells has dropped to the point of competing with wind power. Some of the first students who left China after Mao's death were among those who came into Professor Green's lab and contributed to this research. Many of them returned to China to set up production of solar cells while maintaining ties with Australia. This was supported by American money, seen as a safe investment due to Germany's aggressive drive to purchase solar energy. The plot below shows the growth of Chinese production of solar cells.
This increase in production and competition lead to a huge reduction in the costs of solar photovoltaic cells after 2005, as shown below.
Other drivers include the increase in efficiency of solar cells and a reduction in installation costs. We are currently implementing technology from 1970-80s to mass produce cells at ~18% efficiency. This is set to continue to increase up to 25% with more recent technology and even further with multi-layered designs. Eventually, wind and solar will compete with conventional fossil fuels.
Utility-scale solar voltaics are large solar farms that reduce the costs, compared with roof PV, by installing a large number of cells usually in a field. However, there are some significant challenges that have to be overcome before we completely transition to renewables.
What if the sun won't shine?
Solar and wind power both have one major drawback: they are intermittent power sources. Our power supply system relies on power sources that are continually generating. This demands large-scale deployment of power storage to be able to help iron out the fluctuations in the power produced from renewables. While hydro pumping is the most advanced energy storage method (pumping water up into a dam) and allows for the largest amount of energy to be stored it is limited by the requirement for a particular kind of geography (some are suggesting using underground caverns to mitigate this problem). Battery technology really needs to step up and take a much larger section of the power storage capacity if we are able to make use of the renewables. Professor Anthony Chen from the University of West Indies mentioned that using batteries to respond very quickly to power fluctuations in the grid system could provide a service to the grid and might be able to offset the costs of buying the batteries, a system called frequency regulation. We also need to rapidly develop the capacity and efficiency of batteries to meet this enormous need that will arise. If we consider renewables, it also suggests the need for more biomass and perhaps even nuclear power options in the short term to make sure the new decarbonised grid can supply power reliably.
Professor Jenny Nelson from Imperial College London spoke about another direction, looking into reducing the costs of the manufacturing the solar cells by synthesising them from organic molecules. These organic photovoltaics are significantly less efficient than silicon PVs but are potentially cheaper to make and able to be sprayed onto windows or plastics. This could reduce the costs of solar cells and help to make up for the storage costs.
Presenting my own work
I presented a poster about my PhD thesis, on reducing the amount of soot produced during combustion. Below is a picture taken at the poster session and I have uploaded a copy of the poster that you can read. Feel free to ask any questions in the comments.
Convincing the public and policy makers about climate change
It is one thing to have possible technology-based options for dealing with climate change, but this is not enough to solve the problem; we need cooperation from everyone up to their leaders. During the first opening plenary, Sir David King spoke about how to shift the discussion around climate change. He began with a story of when he was the Government Chief Scientific Advisor in the United Kingdom and was working to combat a bad outbreak of foot and mouth disease. There was no plan on how to deal with such a problem and it was difficult to manage. After the disaster, he began to think that there must be a better way to prepare for such events. Thus began the development of a plan on how to prepare for flooding in the UK. The idea was a small investment in preemptive action that will reduce the impact of this type of disaster. Many different steps were taken to prepare England for bad flooding, making use of weather models and cutting edge science. In 2015, this type of flooding did occur. The damage was extreme, exceeding five billion dollars, but substantially less than if they had not taken preventive action. It was later calculated that every pound spent in prevention provided a reduction in potential cost from disaster mitigation of seven to eight pounds.
In studying the risk associated with flooding, the impact of climate change was also beginning to be taken into account. This posed some serious problems and led the researchers and government to begin considering the risks associated with climate change for the UK. They asked themselves if they could afford to wait for climate change to happen, or if they should act straight away.
One of the risks that the world already face as a result of climate change is an increase in the number and severity of heatwaves. In 2003, a heatwave in Europe killed 70,000 people [1]. Climate science focuses on the average long term changes in the climate; this doesn’t always help to communicate the actual costs associated with climate change (think of Trump's suggestion that a two degree change will not be significant). It will be the rare, big-impact events that will cause the greatest loss of life and capital. These are the most important factors to consider and to mitigate. Considering the heatwave of 2003, the plot below shows the actual temperature in black with some other traces plotting simulations. The rare event that occurred in 2015 is what led to the huge loss of life, however as the temperature increases the chance of a similar event increases proportionally compared with the new baseline. It is also frightening to see that by 2040 the average summer temperature in Europe will be that of the heatwave in 2015.
One of the risks that the world already face as a result of climate change is an increase in the number and severity of heatwaves. In 2003, a heatwave in Europe killed 70,000 people [1]. Climate science focuses on the average long term changes in the climate; this doesn’t always help to communicate the actual costs associated with climate change (think of Trump's suggestion that a two degree change will not be significant). It will be the rare, big-impact events that will cause the greatest loss of life and capital. These are the most important factors to consider and to mitigate. Considering the heatwave of 2003, the plot below shows the actual temperature in black with some other traces plotting simulations. The rare event that occurred in 2015 is what led to the huge loss of life, however as the temperature increases the chance of a similar event increases proportionally compared with the new baseline. It is also frightening to see that by 2040 the average summer temperature in Europe will be that of the heatwave in 2015.
European summer temperature different from 1900 temperature levels. [2]
What Sir David King decided to do in order to convince communities about the impact of global warming was to bring in people from the insurance community who are experts in predicting the risk of rare events, to predict the risks associated with global warming in the UK, US, China and India. They were able to make predictions on the chance or risk of a serious disaster happening given different climate scenarios. For example, the chance of crop failure in the US and China head towards 25% (maize) and 75% (rice) respectively with a global temperature rise of around 4-5°C. This helped spur on nations leading up to the Paris agreement, encouraging China, US and India to join. In his discussion of the Paris agreement, he explained the subtle way they plan to make it work. The Paris agreement does not force anyone to make a commitment but allows countries to provide their bids to reduce their emissions. The clever, subtle, aspect is that there is a review process that considers the cumulative sum of the bids and determines, from climate models, whether we could reach the 2 degrees C target given the current pledges. This information then is relayed back to the countries encouraging them to improve their bids in order to meet the global temperature target. Below is a graph showing the impact of the new pledges (as of the Paris agreement) which will be used in the next review round to encourage countries to get improve their pledges to bring the worlds emissions down into the blue region.
You can see that the new pledges do not meet the less than 2 degrees C target and the next review process will be aiming to encourage countries to improve their bids to meet the 2 degrees C target. (wondering how New Zealand is going well we have an "inadequate" rating, for example, agriculture which accounts for 50% of our greenhouse gas emissions are not included in our emissions trading scheme. However, as we produce most of our electricity through renewable energy we have the potential of being a world leader in climate change reversal and a decarbonised society.) It would be great to have a similar risk assessment done in New Zealand in order to consider the cost of the risks associated with climate change on flooding and crop failure in New Zealand to convince the New Zealanders to act to curb emissions.
In another talk, the question was asked. How do scientists communicate with the public and policy makers to make sure decisions are made without misinformation sneaking in? Sir David Spiegelhalter a statistician and science communicator highlighted the need for scientists to be part of the entire communication process. Here is a figure he showed (which I reproduced).
He mentioned a study which showed that the exaggeration of claims in the news are predominately introduced at the universities press office. This means scientists need to be involved in the communication of their research coming out of the press office in their own university and along every step of the communication pathway in order to maintain accuracy. He also talked about empowering the public to be more critical about the information they are receiving (which is partially encouraged by the fact checking regulators).
This level of critique and commentary relies on the trust and integrity of the scientific community. My small contribution to the discussion during the policy discussion was a question about whether the commercialisation of science undermines the public's trust in scientists that are seen to have conflicts of interest. This was further discussed by the head of the Royal Society Sir Venki Ramakrishnan comment in the second policy panel discussion who asked whether the over industrialisation of science undermines its core values. Sir David King spoke about the need for scientists to be taught about ethics and the importance of being transparent in our discussions of science. He pointed to his work on developing an ethical framework for scientists. Just as doctors have to agree to a certain set of ethical principles his hope is that scientists will follow a similar path. I will leave you with the seven principles;
- Act with skill and care, keep skills up to date
- Prevent corrupt practice and declare conflicts of interest
- Respect and acknowledge the work of other scientists
- Ensure that research is justified and lawful
- Minimise impacts on people, animals and the environment
- Discuss issues science raises for society
- Do not mislead; present evidence honestly
References
[1] "Death toll exceeded 70,000 in Europe during the summer of 2003". Comptes Rendus Biologies. 331 (2): 171–178. ISSN 1631-0691. PMID 18241810. doi:10.1016/j.crvi.2007.12.001.
[2] http://www.nature.com/nature/journal/v432/n7017/abs/nature03089.html
