Is it time for a radical new approach to fighting global warming?


25 June 2019

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One may call it a crazy idea. Someone else may say its an expression of desperation about the lack of action on climate change. Despite the regretful tone, however, these comments are from researchers who advocate further study into whether climate engineering could be part of the answer to alleviate global warming.

Climate engineering, or geoengineering, is a broad term that can cover a range of potentially large-scale interventions in the Earth’s climate, in a bid to reduce or reverse the warming trend. In one concept that has been contemplated by researchers, aircrafts would spray reflective aerosol particles into the stratosphere to reflect some sunlight back out to space. This would aim to replicate the cooling effect of sulphate particles churned out by volcanic eruptions. Such an effort would likely be an ongoing operation, and have to be globally coordinated, to be effective.

This may sound like a dramatic or risky approach, but advocates for further research say the only reason it’s being contemplated is that the world’s political leaders have failed to cut greenhouse gas emissions deeply enough to avoid the most severe impacts of a hotter climate.

“I always describe the idea of doing geoengineering to be insane – and it is,” says Professor John Moore, who leads a geoengineering research program at Beijing Normal University.

“No sane society would choose to do geoengineering. The fact that we are having to look at it is because the correct course of action requires more courage than the political leadership around the world has. So, that’s why we’re in this position.”

Andy Parker, an honorary research fellow at the University of Bristol, says in a Skype call with Global Ground Media that the 2015 Paris Agreement to cut global emissions was “an absolutely crucial necessary step forward for climate policy.” However, he warns that, even if nations cut their emissions by the promised amounts, the world would remain on track to get warmer by more than 3 degrees Celsius above pre-industrial levels.

Under the Paris Agreement, countries committed to keeping the global temperature increase this century to “well below” 2 degrees Celsius while aiming to try and contain it to 1.5 degrees Celsius.

However, each country that signed the agreement was given the freedom to set its own emission reduction targets, and the United States under President Donald Trump has since walked away from the deal. According to an analysis by the Climate Action Tracker, the policies presently in place around the world are projected to “result in about 3.3 degrees Celsius warming above pre-industrial levels.”

On-screen, Parker sits in front of a collection of bones of the long-extinct saber-toothed tiger in the University of Bristol’s Department of Earth Sciences. He now contemplates the risk to humanity from climate change, underlining the scale of the emergency: “I think the fact that people are studying SRM [Solar Radiation Management], seriously considering sun-blocking, is an expression of desperation about the state of climate risk.”

He continues: “The fact that we’ve known about climate change for decades and yet people have not been acting nearly fast enough, cutting emissions far enough, fast enough, to avoid what looks like a pretty high level of climate risk…that’s what’s caused people to start looking at these alternative approaches.”

Parker is also Project Director of the SRM Governance Initiative, which aims to foster debates about how such proposals would be managed if implemented – a daunting task given the competing interests of countries around the world. The initiative is an international project based at The World Academy of Sciences in Trieste, Italy, and the Environmental Defense Fund in San Francisco, USA. The initiative recently awarded grants to eight research teams to assess the impacts of such interventions on developing countries and emerging economies, on the basis that these voices must be part of the global climate conversation.

“Simply put, solar geoengineering matters more to developing countries,” Parker says as he explains the rationale of the latest research focus.

“Typically, developing countries are on the frontline of climate change, and therefore if SRM works really well, they stand to gain the most. If it goes wrong and there are horrible side effects and so on, then developing countries stand to lose the most, and that’s because they are typically less resilient to environmental change than the world’s richest countries. And so, developing countries should play a central role in the research, discussion and evaluation of geoengineering, but to date, most of the research has taken place in the world’s rich countries.”

The eight modelling projects will share a total of US$430,000 in grants provided by the Developing Country Impacts Modelling Analysis for SRM (DECIMALS) fund by the SRM Governance Initiative, which received support from the Open Philanthropy Project. The projects were selected from among 75 proposals from 30 countries.

Each project has a different focus on working out what the pros and cons of geoengineering would be in their country or region. Researchers emphasise that they are not conducting outdoor experiments, but instead using computer-based modelling to quantify the potential impacts.

In Indonesia, for example, a research team will assess how climate engineering could alter the incidence of floods and droughts in the country. The team, which is based at the Sepuluh Nopember Institute of Technology in Surabaya, East Java, will also examine the possible impact on the heat stress index, a measure that takes into account not only temperature but also humidity. When the index is high, people can be vulnerable to heat stress, a potentially dangerous condition that can lead to dehydration and even death.

“Because of climate change, floods happen more frequently in many places in Indonesia during the wet season due to heavy precipitation [rainfall],” explains the Principal Investigator of the project, Heri Kuswanto, who is also Coordinator of the Climate Change Group at the Sepuluh Nopember Institute of Technology’s Centre for Earth, Disaster and Climate Change.

“Meanwhile, drought duration and magnitude in some parts of Indonesia are higher and higher over time.”

Kuswanto says that research is essential to Indonesia, as it is one of the most vulnerable countries to the impacts of climate change. “Shifting the seasonal period, prolonged drought, higher intensity of extreme rainfall are some [examples of] evidence of climate change impact, among others,” he says. “All of these events are happening now. Indonesia is also getting warmer and warmer over time. If we do not do anything to stop the increasing temperature, what will happen in the next 50, 70 years? What will happen with our kids? What will happen with other animals?”

Kuswanto cautions, however, that the research is not intended to support the deployment of climate engineering. Instead, the researchers “stand in the middle” and aim to indicate whether such interventions would have a positive or negative impact on extreme temperature and precipitation change. “If it is good, then it will provide a scientific justification to continue SRM. If not, then another strategy might need to be explored,” he says.

Climate engineering is likely to present decision-makers with a series of difficult trade-offs – a point perhaps exemplified by the health impacts that will be considered by another DECIMALS-funded research project in Bangladesh.

Achieving a reduction in heat waves and flooding may reduce the incidence of cholera in Bangladesh, but excessive cooling may also increase the prevalence of malaria. The research team, based at the International Centre for Diarrhoeal Disease Research in Dhaka, will look at various scenarios for temperature and rainfall levels and analyse what that would mean for health outcomes.

Researcher Mohammed Mofizur Rahman, who is a co-principal investigator on the project, says he has seen meta-analysis suggesting that the temperature tolerance window for the malaria vector (carrier) is changing. The research team will examine what this means for malaria transmission if SRM is implemented. “So, we want to test it in computer simulations.”

Like the other researchers, Rahman says he is neither in favour nor against climate engineering; he wants to help ensure an informed debate.

Bangladesh, one of the most climate-vulnerable countries, needs to develop its own research base to ensure it can make decisions that take into account local impacts, he adds.

“The people who are really affected – their voice is not heard,” Rahman says.

Parker describes the Bangladesh project as “a nice little microcosm for the analysis of all of SRM itself in that they’re going to be carefully working through the complex potential benefits and risks, and they’re not going to find it’s all benefit, and they’re not going to find it’s all risk.”

Instead, Parker concedes, “it’s likely to be a messy mixed picture. Working out who it might benefit or harm and where and when is a good first step to being able to make an informed evaluation of it.”

Moore, of Beijing Normal University, will serve as a research collaborator on the DECIMALS projects, helping the teams to understand how to use the existing climate engineering models and apply them to their own research questions.

“I think that the conversation that’s been had to date,” Moore says, “has been far too much from the Western-centric viewpoint, and I think that the voices of the people who are being very strongly impacted by climate change already absolutely need to be heard on this far stronger than they have been.”

‘Masking’ the problem

While research continues, climate engineering has no shortage of critics.

The Intergovernmental Panel on Climate Change (IPCC) has previously described SRM as “untested” and suggested it “would entail numerous uncertainties, side effects, risks and shortcomings and has particular governance and ethical implications.”

“In spite of the estimated low potential costs of some SRM deployment technologies, they will not necessarily pass a benefit-cost test that takes account of the range of risks and side effects,” the IPCC said in its Fifth Assessment Report in 2014.

More recently, a paper published by the Climate Analytics think-tank similarly argued the risks would be too high. It noted that SRM is not a comprehensive solution to climate change, as it would merely “mask warming temporarily” and would not save coral reefs from severe damage, for example.

“Solar radiation management does not halt, reverse or address in any other way the profound and dangerous problem of ocean acidification, which threatens coral reefs and marine life, as it does not reduce CO2 emissions and hence influence atmospheric CO2 concentration,” said the authors of the paper, which was published in December 2018.

“SRM does not counter other effects of increased CO2 concentration adversely affecting the terrestrial and marine biosphere.”

The authors also argued that SRM might undermine the potential of solar energy projects and affect food production efforts because it would reduce the amount of solar radiation reaching the Earth’s surface.

Among the environmental movement, some fear the latest research effort could take attention away from the critical task of rapidly shifting from fossil fuels to clean energy.

“Experimenting with risky technologies such as Solar Radiation Management and other geoengineering techniques is not the answer to the current climate crisis, but a dangerous distraction from the task of tackling emissions at [the] source,” says Sara Shaw, the Climate Justice and Energy International Programme Co-coordinator at Friends of the Earth International.

“Chasing wild geoengineering fantasies will only let fossil fuel companies off the hook and delay the much-needed energy revolution.”

Shaw adds that interference in complex climate and ocean systems “is likely to have severe and irreversible impacts on ecosystems and people.”

Parker, on the other hand, believes the risks of geoengineering need to be weighed against the risks of global warming continuing to dangerous levels.

“Chemotherapy is horrible, it’s dangerous, it’s unpleasant, it’s got very nasty physical side effects and so on, but whether or not one should undertake a course of chemotherapy is based on [the] perception of the risks of cancer,” Parker says.

“And so it goes with solar geoengineering: no one in their right mind would just want to do this, but it’s a response to a potentially even bigger threat. And as with anyone trying to make their mind up about a risky course of action, it’s about balancing risks.”

Just as the risks of chemotherapy could only be understood by also looking at the risks of cancer, “the risks of doing solar geoengineering can only be understood by looking at the risks of not doing solar geoengineering and seeing the temperatures continue to rise,” he adds.

Moore, too, points to the impacts of climate change as a reason to investigate geoengineering options. Referring to some of the business-as-usual scenarios for greenhouse gas emissions, he says, “there’s ample evidence that those will be utterly disastrous from every perspective – sea level, agricultural, you name it.”

Meanwhile, Masahiro Sugiyama, an Associate Professor at the Institute for Future Initiatives at the University of Tokyo (previously the Policy Alternatives Research Institute), characterises climate engineering as “an insurance policy” that is worthy of further research.

Sugiyama has been part of several projects to gauge public reaction to the idea of geoengineering in Japan. He notes that the general public is not overly familiar with geoengineering – a fact confirmed when Global Ground Media approached people on the street in Tokyo in late March to ask them if they had heard of it.

Sugiyama and other researchers conducted focus groups with Japanese citizens in 2015 on the concept of geoengineering in general, and field trials of stratospheric aerosol injection in particular, which required explanation.

“Awareness is very low, first, and people are rightfully scared of the possibility of geoengineering, and I think they were worried about the potential side effects of geoengineering,” he says. “I think one interviewee said we should test this by spraying the aerosols onto the scientist who is advocating this technology.”

Sugiyama says people are hesitant because they see the climate system as complex and interconnected. They know, for example, that a train accident in one part of Japan can have flow-on disruptions across the entire rail network. “People, out of their experience, they know it has to be complex,” he explains. “So, whenever we tweak one aspect of the climate, what kind of impacts would it have on the other parts of the climate? They’re naturally concerned about these sorts of environmental side effects.”

However, Sugiyama says focus group interviewees did not immediately exclude geoengineering, and were open to more research being done, so long as adequate controls were put in place.

Researchers working on the DECIMALS projects are due to present their findings by the end of 2020, but, in the meantime, they plan to stimulate discussion about the issues at stake in their countries by hosting workshops with experts, policymakers, non-governmental organisations and the general public.

Parker maintains that a reduction in greenhouse gas emissions must remain the primary policy goal for governments around the world – an effort that must “massively increase.” SRM, he contends, should be seen as a potential way of reducing the risks posed by the greenhouse gases that countries have already emitted. The Earth has already warmed by about 1 degree Celsius above pre-industrial levels, and climate scientists have noted that even if emissions from burning fossil fuels ended today, there would still be a further amount of “committed warming” due to the lag time in air-temperature increase.

Scientists at the United Nations’ Intergovernmental Panel on Climate Change (IPCC) sounded the alarm last October when they found that a 1.5 degree Celsius increase should be the absolute maximum after unexpected rapid melting of polar ice. According to them, humankind currently only has 11 years left to radically reduce emissions or face the consequences.

When weighing up the risks from the potential deployment of SRM in the future, Parker says the socio-political dimension concerns him the most, because, in theory, one country could choose to deploy the technology unilaterally and affect the entire planet.

“So, what would happen in response to that? Would you get geoengineering leading to conflict, and even war, between nations?” Parker asks.

“Even if geoengineering worked perfectly, which it never would, but even if it worked perfectly and we knew there wouldn’t be any side effects and so on, how would you get agreement between, say, Russia, and India on where to set the global thermostat? Because, in isolation, Russia might benefit from a warmer planet [and] it seems likely that India would suffer disproportionately. And so how do you get agreement even to turn the system off?”

SRM, Parker adds, can never be an alternative to cutting emissions. “It can only ever imperfectly mask the impacts of warming. It doesn’t solve the problem. It might be able to reduce some risks, but really if we want a sane climate future, any sane climate future is based on massive emissions cuts, as soon as we can manage those cuts.”

Article by Daniel Hurst.
Editing by Mike Tatarski.
Video editing by Katya Skvortsova.
Illustrations by Imad Gebrayel.
Animation by Denis Chernysh.

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