The Hidden Methane Time Bomb That Could Accelerate The Climate Crisis

0:00And now a word from our sponsor South by Southwest London. Imagine a future where things just make sense. In the 1700s, we had canals. In the 1800s, the railways. Then telecom, fibre optic. And now? In a world that's more unsure than ever before, we need the answers. South by Southwest London presents over 900 speakers, 200 music artists, and 100 films in one location in June. To find out how they merge together and shape the future in person, visit southbysouthwestlondon.com. That's S-X-S-W-LON-DON.COM Melting ice caps are bad for lots of reasons. One we don't talk about so much is that the melting could allow massive amounts of methane frozen under the ice to bubble out into the atmosphere, which would be really bad.

0:46Yeah, really bad. Methane is a greenhouse gas that is far more potent than carbon dioxide. It can cause 86 times as much warming per molecule as CO2 over a 20-year period. and that's why stopping things like methane leaks from gas pipelines is really important. Yeah, we hear quite a lot about those pipeline leaks and it's important to stop those. But, you know, at least they're fixable and the amount that comes out of those is quite small, relatively small. But for frozen methane, some estimates of all the methane that's frozen under the ice but also deep under the ocean suggests that there's more warming potential in the methane than all the coal, oil and gas on Earth.

1:28So massive amount. If it leaks out, it would just be unmitigated disaster, he said with a smile on his face. From New Scientist, this is the world, the universe and us. I'm Dr Penny Sarsha. And I'm Dr Owen Hooper. We're joined today by climate reporter Alec Loon. Alec, let's start with some chemistry. What are methane hydrates? Yeah, it's super interesting stuff. It is, I mean, it's like ice, but it's not technically what it is. It's a lattice of frozen H2O molecules. And within that kind of cage is trapped methane molecules. And so you get this kind of weird substance where it's 85 % water, but it burns because there's gas trapped inside of it.

2:17So it's a really unusual chemistry and it really only happens at low temperatures and high pressure. And the places where you get that are essentially underneath ice sheets and deep underneath the ocean. So that's where we see these methane hydrates. It's really hard to say how many or how much of this methane there is trapped in these hydrates, but it's definitely big. Right. But there is some evidence in the past that climate change in the past and like, you know, 10 ,000 or more years ago has allowed some of this stuff to escape and get out and even to explode. Yeah, I mean, we kind of find the traces of it in these mysterious craters under the ocean or in permafrost regions.

3:00So I was actually working as a foreign correspondent in Russia in the mid-2010s when this giant crater was discovered in the middle of Siberia. Some people flying in a helicopter discovered it and some local reindeer herders had also seen it. and everyone was just baffled. Why is there this? I think it was 50 meters deep. It was about 25 meters across and everyone was just baffled why there was this giant crater in the middle of a very flat, even landscape up in northern Russia. One of the leading theories and scientists actually repelled, descended into that crater and took some measurements and there was a lot of methane at the bottom of it.

3:42And so one of the hypotheses is that there was a methane hydrate in the permafrost. And then as the permafrost thawed, the temperature rose and the pressure decreased to the point that that hydrate exploded out into the surface. And that's what created this crater. That's not the only hypothesis. There's some people who think that this was a gas pocket underneath the permafrost that was kind of uncorked and it wasn't necessarily a hydrate, but it definitely seems like methane exploded out of the permafrost, which is definitely a worrying phenomenon if that's going to be taking place more often as the permafrost thaws.

4:18Yeah. And then there's other craters all over the place that have been picked up by seismic studies. There's ruptures on the seafloor. You know, as you say, there is a lot of uncertainty, but there is a lot of concern that there has been these methane leaks in the past. But the problem is the evidence isn't conclusive. So where are we now with our understanding of how this stuff is coming out? I think it's really rudimentary, our knowledge still of what's going on, because we can't directly observe or measure the methane coming out. We can just see the traces. We see the crater that was left behind, or in the case of this study that I've been reporting on, we see these pockmarks in the ocean floor.

5:00And so then we can just go and do sediment cores, take readings of methane in the immediate atmosphere or in the immediate vicinity in the ocean. and kind of deduce what might have happened, but we don't actually know what is happening. And so, you know, when you talk about the actual mechanism of how this happens, it's all still very uncertain. It's uncertain even, you know, so let's say a methane hydrate is getting released at the bottom of the ocean or underneath an ice sheet that's going into the ocean. Does that methane make it all the way to the atmosphere? That's not certain either. It depends on the concentration of methane in the ocean water, whether that would get high enough that the methane would then be released into the atmosphere.

5:43At least that's what the researchers I was talking to were saying. So it's all very, very uncertain, and we're really not totally clear on how this process is working. So there's this effort to understand then whether these pockmarks on the ocean floor or craters are signs of these methane hydrates being released. But you've been reporting on something different this week. Yeah. So these are pockmarks on the ocean floor, but they're in an area that was covered by glacier during the last glacial maximum, during the last ice age, right? So basically, these scientists were looking over some oil and gas surveys that had been done of the seafloor off of Greenland.

6:23And they noticed these pockmarks. And the pockmarks were kind of grouped right along this berm on the ocean floor. And that berm is the maximum extent of a glacier in northwestern Greenland during the last glacial maximum. And so they said, OK, well, that's interesting. that they originally thought it was icebergs, that icebergs from the glacier were gouging out pockmarks on the ocean floor. But then when they actually went there and took sediment cores, they found two interesting things. One, there was a lot of methane in those soil layers or in that subsea, in the sea bottom layers, the sediment layers.

7:03And two, there was a lot of freshwater there. And neither one of those things were expected, right? Because they didn't think there would be fresh water. I thought, if anything, there'd be salt water in these sediments, right? So the fact that there was fresh water means that something happened with the glacier there, because that's the only real source of a major fresh water influx. And secondly, the methane suggested that there had been this output of methane, because this is an area, like I mentioned, low temperature, high pressure, that's where you find methane hydrates. And this area was perfect for methane hydrates in terms of the temperature and pressure.

7:38So they would have expected methane to be in hydrate form there. Instead, they found it not in hydrate form. And so the conclusion they reached is that sometime after the last glacial maximum, the glacier was receding. That allowed the pressure and temperature to rise. But more importantly, it allowed meltwater from the glacier was flowing out into the ocean. And that meltwater, they think, essentially flushed out these methane hydrates from within the sediments, releasing the methane. Is that something that we thought might happen before? Is this our first inkling that this can happen? No. So this is totally new.

8:16This is essentially a new pathway that methane hydrates could be emitted. We kind of, you know, there'd been research about pressure and temperature changing on the ocean floor, which would emit the methane hydrates. Or in permafrost, like we were talking about, melt water from a glacier flushing out the methane hydrates. That's not something that has been known about or explored before. So, yeah, it's a new pathway to release methane that, as the researchers put it, we thought was in the bank. We thought that this methane would be stable. Like I said, the temperature and pressure conditions are perfect in this area of Greenland for methane hydrates.

8:53And yet this methane hydrate was released in this area. And it's ironic that we only know this because of an oil and gas survey. So thanks for that, fossil fuel industry. When you need to build up your team to handle the growing chaos at work, use Indeed Sponsored Jobs. It gives your job post the boost it needs to be seen and helps reach people with the right skills, certifications and more. Spend less time searching and more time actually interviewing candidates who check all your boxes. Listeners of this show will get a$75 sponsored job credit at Indeed.com slash podcast. That's Indeed.com slash podcast.

9:28Terms and conditions apply. Need a hiring hero? This is a job for Indeed Sponsored Jobs. So this is in what you said, Northwest Greenland, Melville Bay. Do we have any idea of how much methane was released in this event? That's super uncertain as well. They didn't even put it in the paper. But when I talked to the researchers, one of them mentioned that, the lead author mentioned that he had done kind of a back of the envelope calculation. And he estimated that the methane released by this flux of meltwater may have been on the order of 130 million tons of methane. That's a sizable amount. That's a sizable amount when we consider that methane is much more potent than CO2, right?

10:09So, you know, humanity's releasing 40-something billion tons of CO2 each year from fossil fuel emissions, but methane has such a higher impact that 130 million tons, that's essentially the same global warming impact as two years of U.S. fossil fuel emissions. Right. Yeah, so not good. I mean, I know, OK, back of the envelope, but this is just Melville Bay. So if this is happening, you know, Greenland itself is a gigantic place. It could be happening all around there, all around the rest of the Arctic. And that's just the glacier melt. So to be clear, this study, it's looking at a historic event, right?

10:49We're talking sort of 20-ish, 30 ,000 years ago. Within the last 20 ,000 years, probably. OK, but what it's showing us is that when the planet is warming and glaciers retreat and melt, which we know our glaciers are doing now, there's this whole pathway that we didn't know even existed where potentially the meltwater flushes out this banked methane. And so could that already be happening all over the world? Probably not happening yet or we would hopefully notice. We would have detected it, surely. But it is, yeah, it is interesting that it could happen because like we were saying, you know, the temperature and pressure in northwestern Greenland is not expected to change, to be changing to the point that methane hydrates would be released in that particular area.

11:36And yet they have been in the past. So it's clearly a concern. So these methane hydrates are actually in the sediments. So you think about, they talk about pore space between these grains of sediments. So it's not, you know, when you have the permafrost example, you kind of imagine a big chunk of methane hydrate, whereas as this, we're more talking about methane hydrate that's distributed in these tiny pore spaces between grains of sediment. And so that's why this pathway is interesting because, you know, yeah, maybe that wouldn't be destabilized by temperature and pressure changes in any time in the near future.

12:12But it could be destabilized by meltwater rushing through that sediment, being kind of pushed through that sediment by the rapid retreat of the glacier. What about the Antarctic? You know, even bigger, sitting on top of even more of these methane hydrates. What do we know about what's going on there? Yeah, Antarctica is the really big wildcard here because, you know, Greenland we know has some of these methane hydrates, but Antarctica is believed to be sitting on far more methane than Antarctica. It's extremely uncertain. Again, don't really have an idea of how much methane is under Antarctica, but there have been estimates that anywhere between 100 billion to 760 billion tons of methane is in subglacial and marine hydrates.

13:02and the biggest chunk of that would be in Antarctica. I mean, again, that's such a huge range, but even a fraction of that would be huge. Even a fraction of that would rival the amount of methane that's currently being released in the Arctic, which is currently mostly from lakes, wetlands, streams. You get this kind of, this flux of methane from these low oxygen environments at the bottom of an Arctic lake, let's say, but also increasingly from permafrost thaw. I mean, even a fraction of that coming out would be a complete disaster. Even if there's a tiny risk of that happening, it's bad enough for us to throw everything we can at it to not let it happen.

13:44I mean, just last week we were talking about sea level rise, and that's bad enough. This is yet another reason why we have to stop the Antarctic getting to that tipping point, if we can, unless we've already missed that. Yeah. And I think there's two points to be made here. I mean, one is obviously we need to cut fossil fuel emissions as urgently as possible because this is just yet another unpredictable climate impact that happens from the warming temperatures. And it's very kind of it's very unpredictable and sudden and abrupt and could be massive all at the same time. Right. So these are these kind of nonlinear impacts of climate change where everything's fine and then all of a sudden, all at once, a huge bank of methane hydrates gets released.

14:32But the second thing is that it is all at once. It's a bit different than we compared it. This methane hydrate in Melville Bay might have been as much global warming impact as two years of U.S. emissions. But the thing about U.S. emissions is they continue year after year after year. right? So they just keep on piling up, whereas until we get them under control, whereas a methane hydrate, it comes out once and then that's it. It doesn't keep emitting, right? So that's, yeah, that's not to say it's not something to worry about, but it's just to point out that, you know, we throw our hands up about methane hydrates when in fact the elephant in the room, the real shocking impact is our own fossil fuel emissions, which happen, you know, we release these kinds of fossil fuel bombs every single year from every single country.

15:18Yeah, I mean, that has been in the past. Some of the pushback from scientists has been that they think that it diverts attention away from the real problem, which is getting CO2 emissions down. But I think that this is just another part of the poly crisis. It's another thing that we should be concerned about. We should investigate. I mean, people have been calling this for this for a long time. And that's why I was a little bit surprised. We still don't really know that much about it. And we have to rely on fossil fuel industry to get the survey. Well, that's exactly it. A lot of what we do know about methane hydrates, we know because the fossil fuel industry did the research because they're interested in extracting the methane hydrates, right?

15:59So it could be that the methane hydrates don't destabilize and aren't emitted by meltwater in Greenland. But the fossil fuel industry goes and digs them up because they decide that's a good source of fossil fuels we can burn. So, yeah, again, the elephant in the room, the real impact is not methane hybrids. It's humanity's fossil fuel emissions. Methane is often brought up at the COP summits potentially as a low-hanging fruit. The leaky pipelines, these are things that we could go fix now to buy us a bit of time. How are we actually doing on that, dare I ask? So there was a global methane pledge when Joe Biden was president of the U.S.

16:37that basically had the agreement of the U.S., of China, of these big emitters to try and cut down on methane emissions, cut down on this low-hanging fruit. A lot of this is just methane emissions from leaks and pipelines. So it's not good for business. It's not good for anyone, right? We just need to fix leaky pipelines. And then we help the climate. And we help business. And we help business. Yeah. So it's really a win-win. But unfortunately, since Biden left office, since Donald Trump took over, the U.S. has kind of gone AWOL from that methane pledge and doesn't seem to really be taking action anymore on cutting down on these methane leaks from pipelines.

17:18If anything, the US is going in the exact opposite direction, deregulating, removing regulations from fossil fuel companies to get their emissions, to get their lease, to get their act under control when it comes to pollution. That's all for this episode. Thanks to our guest Alec Loon and thanks to you for listening. Do follow and subscribe wherever you get your podcasts. Bye for now. Bye.