The Potential of Stratospheric Aerosol Injection

SAI, or Stratospheric Aerosol Injection, is a proposed geoengineering technique that involves injecting particles into the stratosphere to cool the planet. It is inspired by the cooling effects of volcanic eruptions. SAI could have positive impacts, such as slowing down global warming and increasing ice cover in the Arctic. However, there are many concerns and drawbacks. It could disrupt regional weather patterns and precipitation, which would have devastating effects on countries reliant on rainfall for food production. There is also a risk that people may view SAI as a solution and neglect other climate change efforts. Once SAI is stopped, the sudden temperature change could harm ecosystems. More research is needed before considering SAI as a viable option. Hi everyone, and welcome to this week's episode of Climate Matters. We will be discussing Stratospheric Aerosol Injection, or SAI, as we will be referring to it as that during this episode. With me today, I have Gretchen, a fellow climate enthusiast of sorts, and together we will be talking about if SAI is a solution or a Pandora's box of problems. Gretchen's field of expertise is precipitation. I have brought her here with me today to discuss some of the foreseeing issues with SAI. Yeah, hi everyone, I'm such a fan of the show and super excited to talk about SAI today. Okay, so I realize some of you guys may not know what SAI is, or haven't heard of it before, so I thought I would give a brief introduction just to catch everyone up to speed. SAI is essentially a proposed geoengineering technique that involves injecting tiny reflected particles, such as sulfur dioxide, into the stratosphere to reflect some of the sun's incoming energy back into space, effectively cooling the planet. Yeah, and have you heard how they came up with the idea for SAI? Oh, I have not. Please educate me. Of course. So in 1974, a Russian scientist was observing the impact that volcanic eruptions have had on the environment, and noticed that after major eruptions, such as Mount Pinatubo in 1991, the injection of sulfate aerosols into the stratosphere cools the surface temperature of the planet. The aerosols do what SAI would aim to do, and reflect light into space. The effects from the Mount Pinatubo eruption cooled surface temperatures by about a half a degree for around a year. And yeah, half a degree may not sound like much, but in regards to the climate, half a degree is enough to make a positive impact. Okay, let's dive into some of the positive impacts that SAI would have on Earth. I mean, obviously, it would cool the planet, and it is super fast-acting, so the impacts of the cooling would be felt fast. The reflection of sunlight would overall slow down the rate that global warming is impacting the Earth. So it's all relatively inexpensive, right? Yes, especially compared to some of the other proposed climate solutions, such as switching to only renewable energy sources, or extracting carbon from the atmosphere. SAI has so many projected side effects, and just about the only one that is somewhat positive is that the net cooling of Earth would increase ice cover in the Arctic, adding to the overall cooling. And don't worry about an ice age happening, it definitely will not get that cool, I think. Let's hope not. The polar bears would enjoy that, but I don't think I would. These benefits would be nice, but for the majority of environmental scientists, the downsides completely outweigh them in their opinion. Yes, that is definitely the vibe you get when talking about SAI. For me, one of the major drawbacks to deployment is how it would impact regional weather patterns and precipitation. As a precipitation enthusiast, I wouldn't expect anything else from you. No, no, no. It would actually be really serious, especially countries in Africa and Asia that rely on rainfall for irrigation to produce a large portion of their food production. Even a small change would have devastating impacts. There would need to be some sort of global release plan in place to make sure that the populations in those countries have enough food to survive. Exactly, yes. And getting everyone on the same page for that would be next to impossible. One of the issues that is most concerning to me is the concept that the general public will view SAI as the overall fix to climate change and take their foot off the gas, so to say, with the rest of the solutions that are being implemented. Yeah, and with the tendency of humans to only create change when it's impacting them, I have large doubt that people will continue to take action to the extent that they need to. I mean, just the fact that there was knowledge of climate change for around 130 years before people started to feel the effects and started to take action shows the concept pretty well. I think that it would take attention off the larger, more permanent solutions like reducing carbon emissions. I fully agree. I think people would kind of adopt an out-of-sight, out-of-mind attitude towards the problem, which poses a huge issue for ever stopping using SAI. Once SAI is stopped being deployed and the particles naturally filter out of the atmosphere, the temperature would shoot back from the synthetic to the real temperature. This would shock ecosystems and the world will have very negative effects. Yeah, all of these are surrounded by so much unknown that it's extremely hard to find definite answers to these questions asking how much impact these side effects will have. My conclusion with SAI is that it needs a lot more research to be even fully considered as an option to deploy. But if it comes down to it, technically, it would cool the Earth. It's also important to remember that there are so many more sides to SAI than just what we discussed today. And so if you're interested in this topic, please be sure to do some more research and look into it on your own to fully understand the scope of SAI and its impacts. Yes, please look into it on your own and let me know your thoughts and opinions. I would love to hear what you have to say. And as always, please let me know anyone who you would like to see on Climate Matters as well as any topics you would like me to cover. Well, thank you so much, Annika, for having me on the pod. I had a great time chatting with you today and hopefully I will be invited back. Anytime, Gretchen. Thank you guys so much for tuning in this week and be sure to come back next week to check out the next episode. Peek Peek. It's everything, anything, and all about the Paris Agreement. All right. Bye, guys.