‘Humanity is performing an unprecedented experiment on global temperatures, releasing millions of parts of carbon which had been sequestered for millions of years.’ – Mark Lynas, Author of 6 Degrees: Our Future on a Hotter Planet
I’ve always been fascinated by climate change, so I was excited to attend a recent discussion at the University of Exeter by experts in their fields. This was the final annual meeting of a 4 year project called HELIX, where scientists have been looking at the impacts of climate change.
I’ve written a post about the talk as the speakers responded to a number of important questions which many of us inevitably want answers to!
The research undertaken during the HELIX looked at temperature increases of 1.5 degrees (which is the UN’s new aim), 2 degrees (which we definitely want to keep below according to international policy), and what could happen if we miss those targets and the world temperatures increase by 4-6 degrees. However, we shouldn’t just pay attention to temperature when it comes to human survival; rises in humidity will also have a profound effect on our ability to survive.
Here are just a FEW of the effects of climate change we are already seeing:
- Heatwaves have killed nearly 148,000 people, most in Europe
- Climate change related disasters have cost more than 11 billion dollars damage in US (this is likely to increase dramatically after the recent extreme weather)
- Glaciers are already in recession. If we continue with med-high emissions, we will lose land ice. Present day 100 year even projected to occur every 11 years by 2050, every 1-3 years by 2100. It’s obviously happening and will have an impact inevitably
- El nino affects 60 million people in Africa already, and this is just a window to the future. There were 3 consecutive droughts between 2016-2017 in Somalia , leading to a harvest 37% below usual yields.
- Global food insecurity has increased by around 40 million people since 2015. The main factors leading to this are conflict, drought, flooding, and extreme weather events.
Here are some questions and answers from the experts* surrounding climate change:
What should we be doing as individuals?
Manuel Carmona Yebra: ‘Eat less/no meat, breed less, try not to use car too much, and fly as rarely as you can.’
How much is the USA leaving the Paris COP21 agreement a setback?
Prof. Richard Betts: ‘Trying to speak objectively (I’m a scientist, not a politician), one country pulling out doesn’t make a massive difference, but if it sets an example it could lead to other countries pulling out’.
An increase of 1.5 degrees may not make a difference to you as a human, but what are the implications to the world?
‘Floods seen once in 100 years will now have 50 year return period, and it is implied that flood magnitudes will be much higher because of changing rainfall patterns.’ – Prof. Ashvin Gosain
Prof. Ashvin Gosain: It will be much more beneficial to keep temperatures to rising by 1.5 degrees rather than 2 degrees. A 1.5 degree change is expected to alter distribution patterns of rainfall in SE Asia, having a huge impact on agriculture, particularly as around 60% of agriculture in Asia depends on rainfall not irrigation, as current patterns are suitable to provide good yields.
Even with a 1.5 degree increase in temperature, volumes of rainfall will be disrupted, and the gap between rainfall will increase, leading to less rainy days. This has implications for soil quality, and ultimately, lead to crop failure. This means that S.E. Asia would have to make massive investments in irrigation. Aside from this, flood frequencies will continue to increase, as will the severity of droughts. In Bangladesh, sea level rises are likely to encroach on 10% of their land mass, leading to refugees.
Furthermore, erosion of soil will increase leading to more sediment in reservoirs, encroaching on fresh water.
We need to find sustainable options which are cost-effective and may lead to ‘win-win’ scenarios which are positive for local people.
Would it be more practical to focus on a global population rhetoric? Would it not be fair to adjust perspective to population management?
Prof. Ashvin Gosain: It is difficult to impose rules in a democratic society; one comment made by a politician in the 1970s led to them losing their seat. Education can bring about this change, and it has already been happening.
The rate of population increase in India is now less than it used to be, and is predicted to stabilise around 2030. I think we are capable of managing population in terms of food; managing the population is the key question, as if managed properly, you can still control emissions whilst being populous. In our case (in India), we export our population to the whole world, and we make a good human resource. I’m not saying produce more people, but I’m not promoting producing fewer people.
What is the worst that could happen in a 4-5 degree world?
Prof. Richard Betts: It is important to emphasize that we can’t predict the future precisely. Ultimately, sooner or later we could go beyond the limits that our species can survive. If we reached 12 degrees (which is well above the temperature rises which HELIX looked at), models predict that large areas in tropics could reach 35 degrees upwards; above this, mammals cannot survive as they can’t cool themselves. However, we can’t plausibly predict a 12 degree rise to happen this century, but it could happen in 200 years. Some smaller areas could even reach this by end of century, although this is unlikely.
Prof. Ashvin Gosain: Misusing our resources inefficiently has already happened – in developing countries, most systems are already deteriorated due to their own actions without climate change even happening. If we start managing resources properly and with rules/regulations, this could be beneficial not just for preventing climate change.
‘The worst that could happen is already happening in some developing countries!’ – Ashvin Gosain
Manuel Carmona Yebra: The worst that could happen with increasing global temperatures is that the resulting loss of water could lead to conflict, compounding the situation. The best solution is that we find an alternative energy source to cover global needs – energy is the main contributor to climate change.
Tania Osejo Carrillo: It may be that insurance could be bought relating to weather forecast eventually e.g. providing payouts to farmers during droughts so their businesses are protected. We need to work directly with farmers and implement a training process to improve the capacity of farmers to understand how financial instruments work.
Could water become expensive in a similar way to oil? Could future pricing of water reflect shortages?
Manuel Carmona Yebra: Water has a price but it’s negligible. Whether it will become expensive is contentious as it’s a basic resource. I don’t have clear answers, but water is much more valuable than oil and will become more so as the world warms.
What about the effects of animal agriculture on climate change in relation to methane production, water, and deforestation?
Richard Betts: Agriculture and land use is a major contributor and changes land surface. Methane is quite rightly an issue. I think it is quite clear that reducing emissions from that sector is one important step that could be taken. This is where the boundary between being a scientist and a citizen becomes tricky – I eat meat but I know it is contributing – we should all be thinking about whether we should reduce our meat intakes!
How will river flow change under increasing global temperatures?
Prof. Richard Betts: There is a range of uncertainty, particularly in colder regions (e.g. Siberia), but overall, all models show a projected increase in river flows. There is variation between models, but the current consensus is towards a wetter world with rising temperatures. This means we need to plan for water resources, but we cannot put all resources under one possible outcome as we can’t predict exactly how water systems will change. In some cases, it has been predicted that there could be a 5x increase in the impact of flooding if global temperatures rose by 4 degrees.
How will crop yield change under rising global temperatures?
Prof. Richard Betts: This is one of most important but uncertain areas. We don’t know how CO2 will affect crop yields, as CO2 improves plant growth so to an extent, the rise in CO2 may offset the rise in temperatures. However, this is a very complex issue for which a range of models are needed. Unfortunately, it is most likely that crop yields will decrease but we can’t say exactly how bad it’ll be.
Here are the key outcomes of the HELIX research project:
- The climate IS changing and we ARE causing it.
- The climate changes naturally of course, but the main driver in recent years is human influence
- Recently passed milestone of 400ppm of CO2 this year
- There is a range of uncertainty in projections as the project used over 2 dozen models to show wide range of possibilities
- Changes in hazardous weather, changing vulnerability
- Rising sea levels, flooding, drought, crop yields, heat stress
List of speakers:
- Prof. Ashvin Gosain: Indian institute of technology Delhi
- Prof. Richard Betts (@richardabetts): Chair in Climate Impacts at the University of Exeter, Head of Climate Impacts at the Met Office Hadley Centre
- Dr. Astrid Wissenburg: Director of research at the University of Exeter
- Dr. Tania Osejo Carrillo: Climate change adaptation consultant at the United Nations World Food Programme
- Manuel Carmona Yebra (@CarmonaYebra): Policy Officer – Adaptation to Climate Change, European Commission.
*Reworded slightly as I simply couldn’t type fast enough during the talk, but I have made sure to avoid any misinterpretation!