For some it might sound like science-fiction, and for others a way to counteract what they regard as fake science. Yet many countries in the world have come to see “geoengineering,” also known as “climate engineering,” as a solution to the impact climate change may have on their nations.

Catholic layman Gary Gardner is a senior consultant to Green Faith, a U.S.-based nonprofit organization that looks at sustainability from a multi-faith perspective.

Climate engineering, he argued, “is an emerging global ethical issue that requires the world’s attention soon.”

Speaking with Crux in Rome last week after attending a study session ahead of October’s Synod of Bishops on the Amazon region, Gardner said that geoengineering is a “complicated topic” not only technically but also ethically.

“The one clear ethical principle is that our highest priority should be emissions reductions,” Gardner said, and he’s “preaching” on the issue together with colleagues and over 1,000 scientists who work with the United Nations, because, he said, the world’s population needs to come together, and he sees the role of religion as key.

What follows are excerpts of the conversation Gardner had with Crux on March 1.

Crux: Can we actually engineer the climate?

Gardner: That’s exactly what’s being planned, but it’s complicated and very interesting, so let me step back a bit and set the stage.

In 2015, the global community gathered in Paris agreed that we need to keep the increase in global temperature under 2 degrees, preferably under 1.5. Since Paris, we have not been moving very fast. The intergovernmental panel on climate change came out with a report in October last year, mapping the difference between 1.5 and 2 degrees. The small island states asked for this study because it matters to them. Some of these nations will disappear if the sea rises too much. They want to know, “How much added water in the ocean will get rid of my country?”

It’s a legitimate question … The Intergovernmental Panel on Climate Change (IPCC) came out with this report and it basically said that we need to cut emissions fast. This means, 45 percent by 2030 from [the levels in] 2010. Then half again in the following ten years, and half again so that we’re basically at zero by 2050. It’s a huge challenge. If we don’t, we’ll pass the 1.5 and 2 [degree increase], and maybe three. It’s a real problem.

We’ve seen what happens at less than 1.5, because we’re about one degree up from the pre-industrial revolution levels. We’ve seen the storms, we’ve seen the wildfires in California, we’ve seen what’s happening all around the world with only one degree.

There are skeptics who don’t believe this is science.

They’re all Americans, I’m sure. It really is well accepted around the world. The IPCC is a panel of more than 1,000 scientists from around the world, and they’re more than 98 percent certain that the climate is warming and that it’s the fault of human beings. That is not argued except in the United States, where for lots of reasons, we still doubt about this.

We are warming, all around the world. We’re seeing signs that are convincing even Americans. And we’re not acting quickly enough. That’s kind of scary and you feel as if your back is against the wall here.

Imagine what would happen if someone came and said, we have a solution: Engineering the climate so that the temperature doesn’t rise as much as it otherwise would.

Which can also be translated into “playing God with the climate” …

That’s why our last report was called, “Playing God?”

How science fiction is it? We’ll throw something into the sky and it’s going to rain?

It’s not quite that direct in terms of rain and snow. But there are two strategies they’re talking about.

There are more than a dozen ways to engineer the climate, but they’re divided into two buckets. One is taking carbon dioxide out of the atmosphere, “Carbon Dioxide Removal.” We put too much of it out there, so we’re going to suck it out. A tree does that naturally. There are some natural forms of climate engineering that you can’t argue with. If we reforest parts of Brazil that have been de-forested, that would help. The problem is that, those green solutions are slow and they require huge areas. For the re-forestation to work, we need to find lands the size of India.

Another way to engineer the climate is “Solar Radiation Management,” which implies blocking some of the rays of the sun, deflecting them back to space. A volcano does this for instance, as when it erupts it releases sulfur to the atmosphere and the global temperature actually cools.

The problem with this is that there are many risks we don’t know about quite yet. One of them is the fact that once you commit to this plan, you have to stick with it. You have to do this regularly to keep the solar rays reflected away. But if we continue to release carbon too and then, for some reason, we stopped throwing sulfur into the atmosphere, the temperature would shoot up very quickly depending on how much carbon had accumulated. You would have lots of ecological problems because animals and plants wouldn’t be able to adapt to that rapid change.

If there was a cheaper way of removing the carbon, would that be safer?

Yes. The cheap one takes too long and requires too much area, and the expensive one is too expensive. And the solar rays one is too risky.

But what happens if you’re Bangladesh and you hear that in Alaska and Siberia, the tundra is melting and releasing methane into the atmosphere? Methane is a global warming gas that will do much more harm than carbon dioxide. If you’re Bangladesh or an island nation you’re going to think that releasing methane into the atmosphere sounds really good.

Hence, the ethics of it become really complicated and interesting.

What can religions do?

The biggest thing they can do is insist we take emissions reduction seriously. That’s the only option that has no ecological cost, only benefits, and it’s the groundwork for sustainable development. The reason I’m preaching about this is because one of the scientists at Harvard who wants to reflect away the solar rays is starting tests this year. He’s doing some preliminary tests to determine what he needs. It’s beginning.

I was at the [Vatican’s] Dicastery for Integral Human Development, and I was talking to them about the need for governance. That is participatory governance, that is that all governments will have a say in this, that we insist on reductions, and that we don’t begin the testing until we can actually link it to reductions in emissions.

Another of the disadvantages of reflecting away solar rays is that it’s successful at keeping the temperature down, but it changes the rainfall patterns, including in the Amazon for what the models tell us. But as Pope Francis says, the Amazon is one of the lungs of the world.