The melt and recession of glaciers has been an environmental concern since the early 1900s, and make up a large part of the measurement and communication of climate change today. The study of biogeochemistry and microorganisms on arctic and alpine glaciers requires specialised sensors and inventive approaches to data gathering, which Dr Liz Bagshaw of Cardiff University has just returned from testing in the field.
Today, we’re talking about how glaciology combines physics, engineering and biology, and the importance of climate communications.
Follow Dr Bagshaws work through her staff page at Cardiff University, and find her lab on Twitter: @CardiffColdClim
Original publication:
https://doi.org/10.1017/jog.2018.76
Will:
Hello, I’m Will, welcome to ResearchPod. In this episode: the melt and recession of glaciers has been an environmental concern since the early 1900s, and makes up a large part of the measurement and communication of climate change today. The study of biogeochemistry and microorganisms on Arctic and Alpine glaciers requires specialized sensors and inventive approaches to data gathering, which Dr Liz Bagshaw of Cardiff University has just returned from testing in the field. Today we’re talking about how glaciology combines physics, engineering and biology, and the importance of climate communications. Joining me is Dr Liz Bagshaw, hello.
Dr Bagshaw:
Hello.
Will:
For all our listeners at home, can you tell us about yourself and your current research?
Dr Bagshaw:
I’m a glacial biogeochemist based at the school of earth and natural sciences at Cardiff university and I’m really interested in how melting glaciers are changing their environments downstream and how we can develop new ways of measuring it.
Will:
Now, melting glaciers are a very newsworthy topic at the moment. There’s been the Memorial wreath as it were. The plaque laid for a glacier in… Greenland, was it? Maybe Iceland.
Dr Bagshaw:
Iceland, yeah
Will:
so maybe people have been hearing about that. Can you tell us the modern situation for a glacier in the 21st century?
Dr Bagshaw:
It’s pretty sad day if you’re a glacier in the 21st century and my time as a glaciologist might well be numbered, but certainly uh, Alpine glaciers we’re seeing very, very big changes in, visible changes. You go year to year, you see differences on the ground, the ice sheets, so Greenland and Antarctica, we are also seeing visible changes. Things are happening much, much faster. We’ve just come out of a very big melt season in Greenland just coming to the end now. The biggest melt season since 2012 and these big melt events are increasing in magnitude and in their recurrence intervals. So yeah, we’re seeing big changes all over the world.
Will:
And where is it that you do the most of your work?
Dr Bagshaw:
Most of my work is in Greenland, but I’ve been lucky enough this year to travel to the Alps as well.
Will:
And that was where you were most recently?
Dr Bagshaw:
I was in The Alps last week and in Greenland three weeks before that. So it’s been a busy summer.
Will:
This is probably going to be a very silly question, but is there much difference between an Alpine glacier and a Arctic glacier?
Dr Bagshaw:
It’s not a silly question at all. There are big differences obviously in the size and the amount of area that that Garcia is getting its catchment from. So Greenland is obviously a very, very large ice sheet, and if it were ultimate, then the sea level would rise by about seven meters across the world. Alpine glaciers, If one small glacier were to melt, then it won’t make a huge difference to our sea level. Well, if all of them were to melt at once, then we would see a big change. But what we are finding in Greenland is that some of the that we’ve learned about Alpine glasses in the past are actually becoming more relevant to Greenland glaciers. As we have more Meltwater moving around, then we see that that Meltwater is having to progress through the system and get out to the sea somehow. And some of the things that we’ve learned about the hydrology of that Meltwater going through Alpine glaciers, we’re starting to see that occurring in Greenland as well.
Will:
And was that what you’re observing in your trip last week?
Dr Bagshaw:
Last week we were testing some new sensors that we will use to measure the melt water going through the ice. So there were two systems that we were testing. One was developed with my colleagues at University College London and Lancaster and they were testing a new radar system that will look through the ice and observe different Meltwater layers. And what I was testing was an instrument that we’ve developed in Cardiff and with Bristol university as well to look at ways of communicating data through ice. So we have an instrument called CryoEgg and this takes measurements of Meltwater underneath the ice and we’ll transmit those data back via radio wirelessly through the ice. So we’ve been doing some testing in Greenland this summer. And then in the Alps we would try to do some tests in this Alpine Glaciers, which has a lot more water. So it’s very interesting looking at the radio transmission properties because water is a, a very good stopper of some of the radio frequencies that we use
Will:
and the sensors are just looking for volume of water or any other markers?
Dr Bagshaw:
At the moment we’re looking at three things. We’re looking at the temperature, the pressure and the electrical conductivity and that’s really interesting to us as biogeochemist cause if we can look at the electrical conductivity, that gives us an idea of how long the water has been underneath the glacier. If the water’s been there a long time, it has a good opportunity to interact with all the sediments underneath the ice. So you have high electrical conductivity. If the water hasn’t been there very long, then it has low electrical conductivity because it flows through very, very quickly. And we like electrical conductivity because unlike say pH, it’s a very, very easy measurement to make. It’s simple electrical circuit. So we can use that to give us an idea of how fast the water is flowing through the glacier. Is it going quickly? Is it going slowly? Then we can combine that with our temperature. And our pressure readings to figure out something about how the water is moving underneath the ice.
Will:
Sounds like also then the measure of aging? If there’s any uncertainty about how old that glacier or meltwater system might be…
Dr Bagshaw:
probably not so useful for aging. I think we need to do something with isotopes to learn about the age of the water. So some of my colleagues, particularly in Cardiff and at Bristol have done some very, very interesting work using Silicon isotopes to look at how the drainage system has changed. But what we really want is sort of the transit time of the water. So if you have melting on these glacier surfaces, does that then flow straight down through the glacier and straight out to sea or does it take a really, really long time and if we can figure out how long it takes, that can tell us a little bit about how the structure of the drainage system underneath the ice is working and that structure is really crucial because that then links onto how fast or slow a glacier might be moving. It’s quite exciting for me as bio geochemist who dabbles in technology.
Dr Bagshaw:
Some of our technological resources are really improving at the moment. So that’s very exciting as a data scientist because I can go out and I have new ways to get more and more data and also think about clever ways to get new data. So at the moment I’m working on these quite simple parameters like we talked about the electrical conductivity, the temperature and the pressure. But pH that’s something that I’ve been doing a lot of work on the in the laboratory and now I want to transfer that to field instruments and all these kind of exciting little nerdy developments are really cool for environmental scientists because suddenly we have this whole host of new tools to understand how we’re changing the environment. And that’s, that’s pretty exciting. So yeah, watch this space on environmental sciences. In the next few years.
Will:
I’ve just had the mental image and I apologize already, but “The Day After Tomorrow” of glaciers moving,
Dr Bagshaw:
What a film [laughter]
Will:
A very cinematic experience, I’m sure. But I imagine it’s something that you’ve watched with the professional fist raised in anger.
Dr Bagshaw:
I very much enjoyed that film. And it is my favorite movie genre, science catastrophe. Um, yeah, Day After Tomorrow, The Core, San Andreas, they’re all brilliant. But yes, some of the ideas that they used in that movie. So the Gulf stream shutting down and us all freezing, “Oh no, Ian Holmes freezing to death on the remote weather station!”… Um, some of it was grounded, you know, a toe in reality, you know, there is a lot of research going on about how an increase in fresh water input to the Atlantic could change the circulation of the ocean. So there is some evidence for that. But I think as far as I know, the consensus at the moment is that we’re probably not heading for a dramatic shutdown just yet. And if it were to be a dramatic shutdown, I don’t think it’s going to be quite as traumatic. Much as I would love to see Jake Gyllenhall chasing wolves through New York, probably not going to happen within our lifetime. Certainly.
Will:
Well, it’s a shame to say, but that’s some of the best news I’ve heard in a while.
Dr Bagshaw:
[laughter]Will:
Does the research that you’re doing then inform the most likely case scenario is how these hydrology systems are going to change. You mentioned the increased sea level from a Greenland ice sheet melt. How much is that being carried forward into the rest of research and kind of climate forecasting at the moment?
Dr Bagshaw:
So what we’re trying to do is provide data points for our colleagues who do the modeling on this sort of thing. So what they’re interested in is how far sea ice is out to sea and what that means for changing mass balance. So is the glacier getting bigger or smaller, does that cause it to flow faster or slower? And once it’s going out to see how quickly is it going to melt? But one of the problems is that we don’t know much about the supply issue, drainage systems. We don’t know if you get lots of water going underneath the ice. Does that cause the ice to flow much faster, speak down into the ocean or does it cause the drainage system itself to change, accommodate a lot more water and then actually slow down the ice because you’ve got less lubrication underneath the ice. And one of the things we were doing in Switzerland last week was working with a, a colleague from ETH Zurich who is a subglacial hydrological modeler and he’s the expert on trying to figure out what’s the most realistic way to model these changes in subglacial morphology. And so we want to try and give them some data points because at the moment they’re essentially working blind. They’re saying this is kind of what we know from the few boreholes we have, this is what we know from alpine glaciers. But what we’re trying to say is this is what we think the pressure is at these certain points and we can measure that and try and validate some of their models. So I’ll work feeds directly into the work of the modelers who then can go on to inform policy makers.
Will:
Have there been any successes in validating these models or are things better, worse or is that someone else’s department?
Dr Bagshaw:
That’s a, that’s a very good question. I would recommend some of my other colleagues who are, uh, who are very good at understanding the uncertainty bounds around models, but the models are getting better. So I think we can trust them and you know, they all agree that things are changing. One of the things that we’ve seen recently is yes, these, as I spoke about a little at the beginning, the similarities between Alpine systems and Greenland systems. We are starting to see the data coming out to validate those models and that’s, that’s quite exciting cause it’s something that we’ve been working on for maybe a decade or so. And actually to be able to get the scientific consensus around that is, is quite exciting for us.
Will:
And in the past decade there has been plenty of time for misconception to grow in, especially with the general public and people who just watch disaster films like me.
Dr Bagshaw:
Um, it’s a very interesting time at the moment and it’s, it’s quite a heartening time because scientists have been saying for a long time things are changing. We need to be worried. But scientists are notoriously cautious in their projections because we are trained to say this could happen, but there’s a plus or minus chance of this happening, this much percent, we’re not terribly good at communicating what could happen. Policymakers in return want to know what’s going to happen on this date. And so there’s been a quite a bit communication mismatch between what the scientists want to say and what the policy makers want to hear. But I think scientists have got a lot better in the past few years understanding what policy makes and the public actually need to know and being less conservative in their projections. So in the scientific papers, all the uncertainties will be there. Everything will be done by the book as it were.
Dr Bagshaw:
But do the policy makers need to know the plus or minus? Not really. They need to know where to get that information, but they need to be presented with the most likely scenario. And I think it’s great at the moment because the general public is suddenly being made aware of things. It’s on the front page of newspapers. Again, the climate strikes, the extinction rebellion, all that is helping to spread the word. And I think it’s quite exciting because people are finally starting to listen. It’s been frustrating because we’ve been saying it for 20 years or so, but now people listening, what we need now is action.
Will:
The background I’m coming to this from is admittedly a very biological one, and I did read in some of the papers I’ve seen you’re attached to are the effects of Meltwater on micro organisms and microbiota and the Arctic region. Can I ask for a little bit more information about that?
Dr Bagshaw:
Again, over the past kind of decade or two, there’s been a big change in glaciology and in a glacial biogeochemistry because when people first started out looking at Meltwaters, they thought, Oh, you know, it’s far too cold and it’s dark for half the year. There’s gotta be no microbes living there. It’s a dead zone. But what we found in the past two decades is that because there’s Meltwater where there’s water, there’s life. So the glacial environment is actually teaming with microbes and that’s really cool. So I have a couple of PhD students who work specifically on micro organisms that live on the surface of glaciers and that’s where I did my PhD, was investigating ecosystems on the surface of glaciers in Antarctica. We find that these microbes are responsible for changing some of the chemistry of Meltwater and that’s really important because what the microbes do is they haven’t got really anything to eat, so they have to extract their energy from somewhere.
Dr Bagshaw:
So if you’re on the surface of the ice, then you have some photosynthesizers within the community so they can create energy from the sun and then their colleagues who live in the same ecosystem then eat them up when they die and they’re respiring and we see a little ecosystem happening on the surface of the glacier. And then those microbes along with other microbes that are already living in the rock can be washed down underneath the glacier, and the subglacier environment is a really cool place if you’re a microbe because even though it’s cold and it’s dark, glaciers are really good at crushing up rock when you crush up rock that exposes all the mineral surfaces which the microorganisms can use to extract energy. So even though it seems like a terrible place to live, actually it’s great if you’re a micro organism that lives down that because you’ve got everything you need. And the microbes are good at taking the minerals from the rock and changing them as they kind of munch their way through the rock and then either die off or excrete other nutrients and the nutrients all kind of get passed around between the different components of microbial populations.
Dr Bagshaw:
So then when the melt water flushes out at the end of the season and flushes out some of those dead microorganisms, all the nutrients that were locked up in the bedrock have now been released by those micro organisms and they are in readily available phases. And what we mean by that is they’re easy to chew. In my lectures, I refer to this as the cheeseburger to kale scale. So if you’re a microbe or indeed a human, what you’d really like is big cheeseburger. You eat a cheeseburger, you get an instant boost of energy, boom. But sometimes there are no cheeseburgers available. So you have to eat the kale. The kale, you can get as much energy as you can from a cheeseburger, but it takes you quite a long time. So you have to eat a really big bowl of kale and it’s going to take you probably half a day to get your way through it.
Dr Bagshaw:
But it still releases the same amount of energy. So the microbes have basically munched through all the kale cause there are no cheeseburgers available. But then when they have eaten all the kale and then they themselves have died, they become like cheeseburgers for the next set of micro organisms that live in the ocean. So when that melt water flushes through, flushes out all these tiny microscopic cheeseburgers (That’s a terrible image. There are no actual cheeseburgers) flushes out all these bioavailable nutrients and that can change the biogeochemistry of the ocean. And there’s some really interesting work going on in Bristol, in Florida, in Alaska, quite a few organizations are working on how that influx of nutrient from a Glossier melt is changing the ocean biogeochemistry particularly around Greenland and around Antarctica as well. So that’s some of the uh, the really cool science that’s going on in glacier melt. We’re not just interested in how much melt there is, but we’re interested in what’s in the melt and how that’s changing the earth system
Will:
Well, after that tiny but appetizing summary of the circle of life, I think we’re just about running out of time, but thank you so much for your time today. If people do want to stay up to date about your research, what would be the best place for them to follow you at?
Dr Bagshaw:
So you can check out my website on Cardiff university or I tweet @Cardiffcoldclim, Cardiff cold climate and I tweet on behalf of our research group and you can see what we’re up to in the field and we usually try and get some nice field photos up there as well.
Will:
And for the people listening at home, is there anything that you would like for them to know that you think is going to be useful for informing this public debate generally or just that “There are people working on it and please do trust us. We’re working very hard to give you an answer.”
Dr Bagshaw:
Know that things are changing and things are changing fast and there is scientific consensus. It’s more than 95% now it’s 99.9% the climate is changing, climate is changing quickly and that is going to have a big impact on how we exist as a species on the earth as well as all the other species that exist with us. And the changes that have happened are predominantly because of human activity. So there is no longer any debate on that. People have run the numbers hundreds of thousands of times in different ways. And that’s the answer that comes out. So when you hear someone saying, Oh, well, the climate’s always changed in the past. Yes. The climate has always changed in the past, however, is not changed at the pace or because of human actions. So if you hear someone trying to give those arguments, please do correct them and go and go and tell them about it. There was a very nice article in, believe it was National Geographic a couple of years ago, the sort of eight key facts about how the climate is changing. Read things like that, and be prepared to communicate what you know and don’t, don’t feel afraid cause you don’t think you’re the expert. If you know more than someone else tell them.
Will:
That sounds like a very neat lesson for… So much of the internet to get a hold of, so hopefully this will do some good for them. Thank you again for your time and that’s all from us. Goodbye.
Dr Bagshaw:
Thank you.
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