Science communication and climate change – what have we learned so far?

interview with CONSTRAIN by the EUROPEAN SCIENCE-MEDIA HUB about the challenges of communicating climate change research

What is the CONSTRAIN project and what are its main objectives? What are the key findings so far?

We are a Horizon 2020 project investigating key remaining uncertainties in the climate system (e.g. how gases and aerosols affect the climate) and using this information to improve climate projections for the next few decades.

One of the key findings is that by drastically reducing emissions, we can reduce the rate of global warming by up to half in the coming decades, giving us more time and space to adapt to the impacts of climate change. We also provide yearly updates on the remaining carbon budget – the amount we can emit and still have a good chance of staying within a certain amount of warming. For a 50/50 chance of staying within 1.5˚C this is around 420 gigatonnes of CO₂, or about 10 years of current emissions.

Does that mean that that we only have 10 years to combat climate change before we reach the point of no return?

It doesn’t mean we only have 10 years to combat climate change: every tonne of CO₂ and every bit of warming counts, whether that’s in 10 or 100 years’ time. More warming means worse climate impacts, so if we end up reaching 1.6˚C that’s still better than 1.7˚C.

Put simply, the remaining carbon budget concept gives us a really useful framework for assessing whether climate policies or emissions reductions are on track to limit the rise of global temperature to a certain level, but the main thing to remember is that the budget is small, every tonne of CO₂ emitted adds to global warming, and emissions must fall to net zero by mid-century in order for us to avoid the most dangerous effects of climate change. There is more detail on the carbon budget concept in each of our annual CONSTRAIN Zero In Reports.

How do you present the key goals and findings of your project to the general public? What is the target audience? Could you provide any figures?

We use a lot of different tools for different audiences, but when it comes to the general public, things like radio interviews and podcasts are really effective, as is Twitter. We’ve also held webinars that are available on YouTube, such as the ones we delivered at the United Nations Climate Change Conference COP26. And for our webinar on the latest Intergovernmental Panel on Climate Change (IPCC) report on the climate system, which we held in August 2021 just after the report launch, we had almost 400 people tuning in. Our mailing list has around 300 members.

Our main audience includes policy and decision makers, from across the EU, as well as in the countries most affected by climate change. We try to reach them, with the help of our stakeholder committee, through our annual reports and briefing notes as well as at COP events.

In order to better communicate to a general public, do you ‘translate’ the main findings of your project from scientific language to more citizen-friendly language?

Yes, our annual Zero In reports aim to do just that. For example, the latest report looks at the amount of warming we can expect in the next few decades, depending on which emissions pathway we follow. It tries to demystify some of the concepts that are set out in major climate assessments and agreements, including the latest IPCC report.

We’ve also developed some briefing notes on specific topics, such as what a 1.5˚C degree pathway might look like, and we hope to provide more in future. All of the news stories on our website aim for plain English, often signposting people to more technical reports and papers. We also go further and write articles and blogs for websites such as The Conversation, which aims to connect researchers with the general public. We’re also thinking about some new products, e.g. podcasts and maybe even a graphic novel. And we’ve developed animations and infographics to illustrate some of the concepts we talk about.

One challenge is translating complex science into accessible language without losing integrity. What we think is ‘simple’ sometimes still isn’t if you don’t work in climate science. We’ve tried to address this by having different layers of information in our reports – so an executive summary in plain English, then a more detailed explanation, and finally some scientific background provided as annexes. Also, we have to appreciate that not everyone has English as a first language. We’ve translated some of our content into French and Spanish already, and are looking at more translations for COP27, particularly into Arabic given that it’s being held in Egypt.

Do you cooperate with similar climate change projects to improve communication to a general public?

We work closely with other projects and organisations to get the message out. For example, at COP25 and COP26 we worked with the Global Carbon Project to talk about climate change and the carbon budget. All of our scientists take part in many projects, including other EU-funded projects.

Most of our activities are carried out in collaboration with others. This helps us to learn what works and what doesn’t. We also invite a range of partners to take part in the webinars we run and share their reflections. Furthermore, we are interested in learning from other Horizon 2020 projects and initiatives that focus specifically on science communication, e.g. by inviting them to come and talk to our researchers.

Have you tried to deliver policy recommendations to local or national governments based on your project’s outcomes? Was it successful?

The main way our science is translated into policy is through our involvement in the IPCC process. In addition to our own scientific papers, we had eight lead authors working on the Working Group I report that came out in August 2021. This then informed the negotiations at COP26, and provided an evidence base that was widely accessible. We hope that our reports also inform policy decisions, but these are notoriously hard to track. We do, however, monitor where the reports are cited and have found them cited in a number of interesting places, for instance in statements delivered to the Dutch House of Representatives, a policy paper by the Foundation for European Progressive Studies, and a Committee on the Environment, Public Health and Food Safety report on the European Parliament’s carbon footprint.

Some of our papers have also informed policy documents. For example, our work on Covid-19’s impact on climate is featured in the Commission’s report ‘Climate Action in the Post-Covid-19 World’, which aims to advise policymakers on shaping a greener and more equitable future. We also respond to relevant consultations from the European Commission and the UK Government.

What challenges did you face in delivering the results of your project due to the Covid-19 pandemic? How did your promotional strategy change?

Like everyone else, we shifted our activity online. So for example when COP26 was delayed, we took part in the Virtual Climate Dialogues organised by the UN Framework Convention on Climate Change instead. But actually, going online has given us access to a much wider audience. It’s sometimes been difficult juggling time zones though – for example, our stakeholder committee is based anywhere from South America through Southeast Asia to Australia, so getting everyone together means some early mornings and late nights. But we’ve probably been able to take part in more events than we otherwise would have as we have been able to do them from home.

We also shifted focus at the start of the pandemic and carried out several studies relating to the pandemic itself, which got lots of attention. These included work on the impact of the pandemic on the future climate, the effects of less aviation and the fall in pollution during lockdown itself.

Could you briefly explain the main climate change tendencies related to the Covid-19 pandemic?

In terms of the pandemic’s impact on the future climate, both the study itself and the results were really interesting. During the first lockdown, Google started releasing data on the location of mobile phones to help policy makers understand how restrictions were changing people’s behaviour. This meant we could easily get information on how activity had changed, organised both by country and by sector (industry, residential, transport etc.). We combined the Google information with a global emissions database to estimate how emissions of 10 different pollutants changed during the first lockdown. Then we used a simple climate model to translate these emissions changes into future temperature change.

Despite the huge changes in activity, we found that the first lockdown would only have a tiny impact on the climate – a saving of one hundredth of a degree – mainly because the lockdown emissions drop was just a temporary ‘blip’ in our greenhouse gas trajectory.

But then we looked at post-lockdown recovery options, and found that a strong green recovery (investing in green industries and cutting fossil fuel finance) could prevent enough warming by mid-century to give us a good chance of limiting warming to 1.5°C, in line with the Paris Agreement and the more recent Glasgow Climate Pact that came out of COP26.

So although the actual effect of the first lockdown on the climate was tiny, Covid-19 has brought a massive opportunity to shift towards a low carbon economy, and this could make a huge difference to future climate change and the impacts it might bring.