Ep. 653: Climate Change: Looking at the Variables (2)
Fraser Cain: So, we have a very real example of this situation in the shop in the studio that I'm in right now. Our original garage doors were gonna have these translucent panes of glass along pretty much the entire wall. We have three garage doors that open up the shop. And we had originally were gonna get these, but then they were back-ordered for six months, and so the garage door installers put in opaque solid doors. And we went through this heat wave, and we were just shocked and amazed at how cool the shop was. We had tons of insulation. The sun would hit the garage doors and keep us cool.
And then finally the doors came in, and we got them installed, and suddenly we were like, “Oh God, we built a greenhouse.” And everything changes. Now, the second the sun comes up, the place just heats up many degrees – five, 10 degrees hotter than it is outside. And it's been definitely a learning experience to manage the temperature changes, just by having the difference between having a wall and glass and having the heat trapped inside the shop with us. It's gonna be cool in the winter, but it's definitely work in the summer to kind of moderate the temperature.
Dr. Pamela Gay: And this is something that any of us who've lived in cold climates have experienced in the winter. One of those completely cloudless winter days is going to be so much colder than a completely cloudy day. And this is because those clouds are able to reflect back down – because they're filled with water vapor, water vapor's a greenhouse gas – those clouds are able to reflect back down the heat that's trying to escape. And on those crystal-clear days, you just get frozen ‘cause any heat you might have is escaping.
Fraser Cain: So, which are the components of the atmosphere that are contributing to the variables of the temperature, of the trapped infrared radiation?
Dr. Pamela Gay: So, there's a variety of different problem children. On one hand, you have specific molecules and atoms. Methane is one that when it gets into the atmosphere, CH4, it will eventually break down in the sunlight, but until then it's just gonna work to trap infrared radiation. We also have water vapor, a variety of other complex molecules. And then there's also aerosols and any other large particles that can get lofted up and trapped in the atmosphere can also cause problems.
One of the new forms of research that I hadn't thought about and now find deeply disturbing is we are regularly dropping things down through the atmosphere, burning them up. The bottom basically storage part of the Dragon capsule and other capsules get dropped through the atmosphere. Trash gets dropped through the atmosphere. Dead spacecraft get dropped through the atmosphere. And researchers are now starting to run models to see if when we add all of the stuff and things that was once a spacecraft to the upper parts of our atmosphere, how does that affect things?
And the answer is some of it scatters light away – yay, cool the world. Some of it traps infrared heat, warming the world. And figuring out the balance of how this occurs is something we don't entirely know how to do. And this is one of the problems that keeps cropping up with climate change is there are variables that we realize that we never realized before and we know they're there and we don't entirely know what to do with them. And it's not like the Drake Equation where it's just a fun guessing game to figure out if we're gonna destroy the planet or not, or if there are aliens or not. Aliens, fun; destroying the planet not so much. So, yeah.
Fraser Cain: So, let's talk about the carbon-based elephant in the room – carbon dioxide.
Dr. Pamela Gay: Right. So that's another one of the greenhouse gases, and it's one of the ones that gets released through myriad different industrial processes, and through forest fires. And we're finding that along with methane it is getting released in really weird geological events. There have been sinkholes springing up in Siberia releasing large amounts of greenhouse gases as what was once tundra melts.
We are similarly finding, in places like Greenland, Alaska, the tundra that had remained frozen since human beings first made it to this continent is thawing out and all of the organic material that was either put in the tundra by human beings seeking to freeze things or frozen there through minor freeze thaws that allowed some melting, life emerged, and then it got snowed on, got buried, and over time it just built up new layers of that very carefully growing in the few months that it was possible foliage. And as the stuff thaws, microbes are going in, are processing it, and releasing more gasses.
So, we have human-contributed carbon dioxide, which is the thing that sparked all of this in the first place. There's no denying it when you look at when things started happening.
Fraser Cain: Yeah, I mean, when you think about every variable that could have accounted for the amount of carbon dioxide in the atmosphere, you've got the impact from humans, you've got volcanoes, you've got forest fires, natural occurrence. Scientists have checked this, and it is the human-released carbon dioxide that is the thing that is filling up the – that is contributing the most.
Dr. Pamela Gay: Yes.
Fraser Cain: When you look at the amount of additional carbon dioxide that's going into the atmosphere, it's coming from human emissions. We can track it from where it is emitted to where it ends up in the atmosphere. Can watch the seasonal variations.
Dr. Pamela Gay: And the thing that keeps me awake at night is the realization that there were things that we hadn't thought to account for, like the melting of the tundra. And these things that we hadn't thought to account for are just making things worse. And so, you always know that in complex systems like this you're probably going to forget certain factors, and here the factors that we keep discovering just keep accelerating the problem. And it comes down to, okay, so if this melts, how do all of these other things get affected? And it's, in some cases, as simple as if you melt enough fresh water into the ocean, it changes the thermodynamics of the entire planet.
Fraser Cain: And that kind of leads into the next topic that I wanted to talk about was the feedback effects. The second-order happenings. You mentioned a couple already. You mentioned the fact that with increasing temperatures you're seeing a rise of gasses that had been trapped released from the Arctic regions. We're seeing increased forest fires which are releasing particulate and carbon dioxide into the atmosphere. We're seeing increased amounts of meltwater going into the oceans. Does that change the temperature of the planet or does that just change the local weather patterns for various places?
Dr. Pamela Gay: It changes the energy distribution and the thermal capacity. So, anyone who cooks has probably at some point or another encountered instructions along the lines of boil this in water then add to your soup. And it's sort of like, “But my soup's boiling, why can't I just cook this in my soup?” And I suspect I'm not alone in saying I have attempted to make the dumplings directly in the soup and I have regretted all my life choices for that day and time.
Fraser Cain: Right, every time, yep.
Dr. Pamela Gay: And the issue is that materials that have different compositions are able to share temperatures easier or worse. If you sit on a wooden bench that you are able to measure with your little IR thermometers as being 80 degrees on the surface, it's not going to feel like you're burning. If you sit on a piece of metal that's 80 degrees, it's gonna feel hot, and the difference is the metal has a greater capacity to transfer its heat. So, changing our oceans' salinity, it starts doing things like changing freeze point, changing how energy is transferred.
And there's also the complication of when you add heat to the equatorial regions, you are now triggering bigger storms which create bigger cloud cover which further trap heat.
Fraser Cain: Do clouds trap heat? Or block it?
Dr. Pamela Gay: Yeah, they trap it. I mean, they do both, but if it is a surplus of energy underneath you would like to have radiate away, the failure to radiate away is problematic.
Fraser Cain: Right.
Dr. Pamela Gay: So, the other problem that we have on top of this is when you add fresh water to the ocean, the changing salinity changes how pockets of hot and cold water can rise and sink. And this changes how heat is transferred through the ocean. It actually has the potential to shut down the currents that are what allowed early sailors to get to our continent and what allows England to have palm trees despite being further north than you are in British Columbia.
Fraser Cain: Yeah, it was amazing being in Iceland and being prepared for it being just absolutely – you're at the Arctic Circle, you're expecting it to be just so cold –
Dr. Pamela Gay: Yeah, no.
Fraser Cain: – but it kind of felt like Canada. It felt like home. Felt like, yeah, it was chilly, but it wasn't terrible. And that was the regulating temperature of the ocean currents, which is just absolutely incredible. So, are there any other second-order variables that we would want to throw into this? I guess the loss of ice makes less of the sunlight reflect back out into space.
Dr. Pamela Gay: Yeah, the loss of ice is a major problem. And it also has the added difficulty that once the glaciers are gone, they are currently a major source of drinking water, runoff, just in general keeping major swaths of vast continents well-watered, and, thus, well, not causing deserts.
Fraser Cain: Right.
Dr. Pamela Gay: As the Rhine goes away in Europe, as the Colorado River goes away in North America, entire swaths of land are no longer going to be able to support the current vegetation, which is going to, again, change the retention and reflection of heat. Exposing land that will retain it in completely different ways than the current foliage does.
Fraser Cain: Yeah, I mean, you see you get a forest fire coming through an area like mine and then the vegetation can't come back because it's not wet enough anymore. So instead, you get grassland or maybe you get desert, at a certain point, if the rain cuts down. And a lot of these places are driven by flooding which is driven by glaciers.
Dr. Pamela Gay: Yeah.
Fraser Cain: I've mentioned this in the past. We have a glacier right over top of my city that we can see most of the time when you're driving around inside the city. It's expected it'll be gone in about probably ten years from now, which sucks, ‘cause the icon of our city is this glacier. And it'll be gone. And then will the cities have to change their stationery to no longer use the glacier as their icon?
Anyway, I think we've reached the end of this week's episode. No solutions, just a clarification of all of the variables. If you're gonna write a big math formula, now you have all the pieces to throw in as you solve climate change on your own. Account for all of those. All right, well, thank you, Pamela.
Dr. Pamela Gay: Thank you so much, Fraser. And thank you to all of you out there who support our show on Patreon.com/AstronomyCast.
