“A PARTICULARLY CONTROVERSIAL IDEA”

If anyone knows anything about climate protection and climate change, then it’s got to be the Hungarian diplomat Janos Pasztor. He can look back at a long career at the United Nations (UN) – including his involvement in the UN Environment Management Group and the United Nations Framework Convention on Climate Change. From January 2015 to December 2016, Pasztor even worked as the UN Secretary-General’s chief advisor on climate change and climate protection.

If anyone knows anything about climate protection and climate change, then it’s got to be the Hungarian diplomat Janos Pasztor. He can look back at a long career at the United Nations (UN) – including his involvement in the UN Environment Management Group and the United Nations Framework Convention on Climate Change. From January 2015 to December 2016, Pasztor even worked as the UN Secretary-General’s chief advisor on climate change and climate protection.

MR PASZTOR, YOU’RE INTENSIVELY INVOLVED IN GEO-ENGINEERING, AMONG OTHER THINGS. WHAT EXACTLY COMES UNDER THIS CATEGORY IN YOUR MIND?

Janos Pasztor: Geo-engineering stands for the idea that humans could manipulate the global climate on a large scale – in order to counter human-produced climate change. That’s the general definition. But currently, there’s a debate taking place about what exactly comes under the heading of geo-engineering. That’s why I prefer not to talk about geo-engineering in general, but rather about the different approaches within the field.

SO WHAT APPROACHES ARE THERE THEN?

Pasztor: One idea is to free the air of the billions of tons of CO₂ that we’ve polluted it with. This method is known as carbon dioxide removal (CDR). There are many different approaches to putting it into effect, some natural, some technological. All of them have a snag, though, because none of them can be put into effect rapidly enough and on the appropriate scale. Another possibility would be to reflect sunlight back into space, thereby lowering the global temperature. This method has a number of names – solar radiation modification (SRM), solar radiation management or solar geo-engineering – but so far it exists for the most part on the theoretical plane, in scientific papers and in computer models.

AND IS THERE A THIRD OPTION?

Pasztor: Well, a particularly controversial idea, which also belongs to SRM, is to spray reflecting particles into the stratosphere. However, this so-called stratospheric aerosol injection (SAI) poses several challenges, for instance, as things stand, its potentially unbalanced effects. However, so far it’s really only an idea that has not yet been applied or tested outside a laboratory. All the same, research on stratospheric aerosols is currently being conducted at Harvard University, and this could prove to be relevant for SAI.

WHAT ARE THE ADVANTAGES AND DISADVANTAGES OF THESE TECHNOLOGIES?

Pasztor: Assessing all these GE technologies against the background of the threat of climate change, they have one great advantage: they could reduce the risks of global warming. Some have other advantages too, but this varies from technology to technology. Of course, all of them would also entail costs and come with risks – though these wouldn’t be the same for everyone – and this in turn could lead to compensation claims and liabilities. This makes it difficult to assess the advantages and disadvantages conclusively.

PERHAPS WE NEED TO GO INTO A LITTLE MORE DETAIL: WHAT ABOUT CARBON DIOXIDE REMOVAL?

Pasztor: With regard to CDR, we should keep in mind the International Panel on Climate Change (IPCC), which has said that we’ll have to remove between 100 and 1,000 billion tonnes of CO₂ from the air by 2100. Only then will we be able to keep global warming at 1.5°C or achieve climate neutrality by 2050. To do that, we need CDR. But of course, CDR also comes with risks – such as the extensive use of land, energy and water. Some technologies could also have negative effects on biodiversity, groundwater and soil quality. In this regard, we need to take a closer look at the individual CDR technologies.

WHAT ABOUT SOLAR RADIATION MODIFICATION?

Pasztor: We still know very little about SRM – and we hardly know anything about the advantages and disadvantages, the risks and benefits. However, from the little we know, we’ve concluded that SRM could affect the oceans, the weather, the ozone hole, the clouds in tropospheric layers, biological productivity and even the water cycle. It could also affect geopolitical stability, and throw up cultural and philosophical questions. But, of course, the very same risks could also arise if we fail to do enough to combat climate change.

AND THEN THERE’S STRATOSPHERIC AEROSOL INJECTION...

Pasztor: SAI technology can bring about substantial changes in global temperature – at low cost. However, it also leads of course to various political challenges that need to be discussed.

HOW CAN WE ENSURE THAT WE CAN HANDLE AND CONTROL ALL OF THESE RISKS? LET’S START AGAIN WITH CDR TECHNOLOGY.

Pasztor: The issue needs to be debated within society as a whole. Discussions have already begun, but no conclusions have been reached as yet. If CDR is to be used, governments and other stakeholders must provide political incentives in order for research to be pushed forward – while ensuring that the research, testing and application of CDR is conducted in a safe way. And policy-makers in the international arena would have to deal with the social and economic impacts, and also with accountability, testing, accounting and financing. The UN Framework Convention on Climate Change (UNFCCC) consists of a number of elements that could be used as the basis for a policy framework – though this needs to be elaborated on further. The Convention on Biological Diversity (CBD) or the United Nations Environment Assembly (UNEA) are relevant in this regard too.

THAT ALREADY SOUNDS QUITE DETAILED. WHAT ABOUT SRM?

Pasztor: Discussions about SRM are not as far advanced, but are currently becoming more and more important – because the challenges that lie ahead of us are becoming increasingly clear. Only when these discussions have become well advanced will we be able to make decisions. However, some SRM techniques are already being tested in the field – for this purpose we need a policy guide, a code of conduct, independent monitoring, and protective measures. In the longer term, international control could gain in importance, with the help too of the UN General Assembly, the UNFCCC, the CBD, the London Agreement, the Vienna Agreement and the UN Convention on the Law of the Sea.

WHAT’S YOUR PERSONAL OPINION ON GEO-ENGINEERING?

Pasztor: This isn’t about my personal opinion – even though I’ve dedicated the last four decades of my professional life to environmental protection and the promotion of sustainable development. And now that I’ve got three grandchildren who’ll be living in the environment of the future, it’s also become a matter of personal concern for me, of course. We know from the Intergovernmental Panel on Climate Change (IPCC) that we’ll need to implement CDR on a large scale. However, we can decide as a society how we want to do it, who pays for it and so on. We should all – regardless of the procedures we use – have the opportunity to express our opinions. I’m more interested in these procedures coming into being than in forming my own opinion about what we should ultimately do.

THAT’S WITH REGARD TO CDR. BUT WHAT ABOUT THE OTHER TECHNOLOGIES?

Pasztor: If we look at SRM, the answer is even more difficult. Because we simply don’t know enough about its advantages and disadvantages, or about the details of how it works or could be controlled. All I can say is this: we may have to use some of these technologies – and the big challenge is that we simply can’t reject any of them without learning more about them. That’s why I believe that we currently need more research to expand our knowledge before we can even think about using any of these technologies.

APART FROM THE SPECIFIC TECHNOLOGY USED, COULD IT BE THAT MANY PEOPLE SEE GEO-ENGINEERING AS AN EXCUSE FOR NOT CHANGING THEIR LIFESTYLES – DESPITE CLIMATE CHANGE?

Pasztor: True. There’s a risk that some people and organisations will try to use these ideas – in order to escape the pressure of having to reduce emissions. But the IPCC has clearly said that CDR will be essential in keeping global warming below 1.5°C; that’s why we need to talk about it. It would be negligent of us not to do so. In the case of SRM, we still know too little to decide whether we need to use this technology. But, even in this case, it seems to me that the risk is greater if we limit public debate – we should rather be making sure that we conduct it in a responsible and inclusive way.