 Okay, thank you everyone. So we'll kick off, this is the second press conference of VEGU 21, and excitingly it's named Scientific Sleuthing, Geoforensics and Fingerprinting. And this year's EGU we have more than 14,000 abstracts and 16,000 people from across the globe participating in the meeting. So in case you weren't with us for the press conference just now, my name is Erin Martin Jones, I'm this year's EGU press conference assistant, and I'll be hosting today's session, which will include a question and answer period, following on from presentations by three speakers. To allow members of the media to ask your own questions, we're conducting this, this is a Zoom meeting obviously. And the best way to do this is after all of our speakers have spoken, if you can then please write the letter Q in the chat box to ask a question. And of course you're also welcome to type your questions in, and I can also read them out if that's preferable. So hopefully this won't happen, but if some for some reason zoom suddenly quits, I'll restart the press conference and give you all a few moments just to rejoin the session. So for reference you can find the abstracts and other documents relating to the press conference, all uploaded to the documents section of the online press center. That's media.edu.eu. So you can have a look there for more information. And I will introduce our three panelists now to make for faster transitions in between them. So yes, so this is the press conference theme scientific sleuthing and scientific sleuthing. If you can say that today are firstly, Dr Christine Sidaway, who is a professor at Colorado College in the United States. Dr Chiara Teloli, who is a researcher at the Italian National Agency for new technologies, energy and sustainable economic development in Italy. And last but not least we have Laura Crick, who is a doctoral candidate at the University of St Andrews United Kingdom. So I will now pass the floor over to each of these speakers in turn starting with Christine to introduce their topic. So Christine are you ready. Yes, indeed. I'll go ahead and share screen. Excellent. And do alert me while I'm screen sharing I can't see time so please alert me when I need to stop. So I'd like to share with you some exciting results from 2019 international ocean drilling that took place on the continental rise of the Amundsen Sea Antarctica. This region is of quite some interest because the nearby glaciers and ice streams of the West Antarctic ice sheet have been deemed the doomsday glaciers. The purpose of the drilling was to discover evidence from sediment records for peeling paleo events that may resemble what is going on presently with ice sheet change. The major findings from study of 5 million year old and younger deep sea sediments are that even in this very deep marine location there are rock fragments that were rafted to the sites by icebergs. And the number grafting specifically occurs during de glacial events when the West Antarctic ice sheet must have retreated dramatically, possibly to Alpine ice camps on the high mountain ranges in West Antarctica. We characterize the rocks recovered from the deep seabed and compared them to online geology of Antarctica to identify where the fragments came from. There are dropstones of a unique green sandstone that could only have originated in interior mountain ranges far from the coast. The West Antarctic ice sheet therefore must have been absent or drastically retreated at this time of ice rafting about 4 million years ago. 4 million years ago is a time that's viewed as a proxy for global climate change of the future in that there's sedimentary records from coastal areas around the northern hemisphere showing that shorelines moved inland at that time. Climate scientists forecast that sea levels are again on the rise and the change may come very rapidly within decades. The drill sites that Expedition 379 to the Amundsen Sea investigated are so far from the coast of Antarctica that we could not see the continent. These are in water depths and distances that no stream river or beach processes could have supplied pebbles, cobbles, and boulders to the site. This is how we know their ice rafted debris. The pulling up cores from the seabed is the action of this drill ship, the famed and historic Jordy's resolution. Zooming in on some of those sections, we saw in the main what we expected to see lots and lots of thinly laminated mud deposited in quiet conditions. What we were hoping for, but we're almost afraid to find are iceberg rafting pebbles and granules and sometimes visible identifiable stones that are indicators of glacial events. My role in the expedition was to study these rocky particles and small pebbles and stones that were introduced into the base of the West Antarctic ice sheet by interaction of the thick ice pressing upon bedrock, headed to the edge of the continent, calved off or broken and then carried into icebergs that once in the warmer ocean water melted and dropped material to the sea bottom that revealed where the ice sheet had been on the continent, and where rock material must have come from some signature types of material or volcanic glass as is shown here. And do last a long time. Here's an example, a modern example of one of the hundreds of icebergs the Jordy's resolution crew tracked, each of them dropping debris to the bottom. And the comparisons underway show specific sites that these icebergs and their entrained rock came from, mostly along the coast of West Antarctica showing that the sediment cores are very sensitive indicators to the advance and retreat of this ice sheet on West Antarctica. We discovered at times that the ice sheet retreats all the way back to the Ellsworth mountains. And when the ice sheet here shown in a transparent layer has melted away stones of the type shown in this green dropstone can be floated upon icebergs along the interior passage in Antarctica to spin north out to the Scotia Sea or come out to the Amundsen Sea and drop this rich evidence on the seabed. So I'd like to stop there and look forward to hearing from our next speaker. Thank you, Christine, for that interesting introduction there. So next let's head over to Dr Kiara Tello, tell only if Kiara is about. Okay. Thank you. So, but only the introduction on all my presentation. Oh, you're so you can show your presentation. That's right. Yeah. Okay, okay. Okay, can you see. Yep. Okay, so I am character lolly from DNA research center in Bologna. And I'm talking about the possibility of extra virgin olive oil. In a fast growing expansion of the free market together with the relatives with which food products are transported through and between countries and continents. The safety and the quality of what we daily it has become a real issue I lightening the structural need for measures to identify the origin of the food commodities for both consumers and the producers. We demand the food stuff with identifiable origin and specific characteristics, and the producers, including for example, like the cultural farmers, retailers and administrative authorities, reclaim reliable or all methods that will be put on their market. For this reason, it is important to evaluate the food traceability and the food authentication. Food traceability covers all processing, producing and distribution steps to better characterize a food product and food authentication is the comparison between same time of products based on a geographical technical or processing difference. The approach on food traceability regards different tasks development, putting side by side the increasing legislations that aims at protecting the origin and the reputation of food commodities, preventing adulteration, and the continuous research on implementation for reliable technologies in order to reach a functioning control system. To do that, different markets have to be chosen to successfully represent the entire change of product, as for example macro and trace elements, ultra trace rare earth elements, contaminants and isotope ratios. As a case study, we collected samples of extra virgin olive oil in meals in different parts of Italy and different years. And we selected extra virgin olive oil because it is a characteristic product of the Mediterranean area, but due to its high nutritional value and high cost of production, it could be subject to fraud. So we analyzed all the samples using an instrument called the inductively co-platplasma mass spectrometer, but in this case is a triple quadrupole. And the implementation of high level laboratory facilities for trace element and isotopic analysis was realized at the Nea Brasimone research center that is near Bologna. We are present both a clean laboratory for sample pretreatment and preparation and a clean room with a controlled pressure, temperature and humidity in where the triple quadrupole is present. The importance of the clean room is to better prevent alteration due to atmospheric fallout and reduce natural contamination of samples, especially during trace and ultra trace analysis. So this is an example of the results. It's not easy to read, but only to give you an example. If you see these graphs, you can show the different fingerprint of the different kind of samples that were representative of different markers. As for example, if you see the graph, so on the right part, in the central Italy, the extra virgin olive oil of Liguria, colored in green, shows high value of rare respect to the other extra virgin olive oil. And the same in the south of Italy is for the extra virgin olive oil of Calabria, colored in yellow. Generally, the extra virgin olive oil of the south has high value of multi-element and rare ultra trace elements. For multi-element, we have value at 120 ppb that is part per billion, respect to 40 ppb in the central Italy, so very, very small. And the same for the array. 40 ppb is part per trillion, so very, very small quantity, respect to 25 ppb. At the end, we analyze all this data in statistical analysis. It is not easy to read, but it is only to give you an example of the importance of statistical analysis. And we use this, we're using, sorry, the principal component analysis called PCA to investigate a possible relationship between extra virgin olive oil samples and analyze elements. The loading plot is a correlation circle that display variables that in our case are the elements in the space. This graph provides information on the correlation between the elements in which F1 and F2 represent the 60% of the variability of the element in the samples. In our case, the sample is the same because it is always extra virgin olive oil, and so there are no high differences, but micro differences that can be linked, for example, or to the territory or to pollution or to alteration, we don't know. In detail in these loading plots, we can see that the most valuable elements are represented by PC1 that represented all the elements and PC2 that explain some of the contaminants, like for example cadmium arsenicum, varium and vanadium. They are the elements at the bottom of the graph on the left in the yellow circle are the constant elements in the samples such as calcium, sodium, so all the elements that we expected to find in the extra virgin olive oil. Taking into consideration ray and contaminants, we see that between them there is an angle greater than 90 degrees, and it indicates that ray and contaminants are correlated to each other. That is, if ray increases in the sample, contaminants also increase. Given that the rays element indicate environmental matrix, while the contaminants anthropogenic matrix, probably, but probably the cultivation soil that could be contaminated. So this is only to give you an example. On the other side, the B plot is used to have an overall graphic idea of what samples and elements studied, in which the information of the loading plot is repeated in the B plot, but including the observation, so including the name of the samples. All the elements are present in all the samples, but in different concentration and to understand in which concentration each element is present in its samples, the sample vector must be projected onto the element vector. This is an example. For example, if I project the vectors of Toscana and Abruzzo in green on the manganese vector, we see that the extra virgin olive oil of Abruzzo affects manganese more than the extra virgin olive oil from Toscana. This is very difficult to read statistical data, but it would be more important because you can give a lot of information, especially if you have a very high database. But with this presentation, I want to put the attention, sorry, on this method, this new technology, so the ICP-MS, but triple quadrupolo, because it's able to analyze trace and neutral trace elements at a very short quantity and very short concentration. And it is important in the case of the extra virgin olive oil, because it could trace the extra virgin olive oil in a very short concentration. In addition, adding the statistical analysis, it is possible to know the relationship between samples and or their origin or maybe adulteration. So this methodology could be applied in a very, a lot of field for a different kind of food products, and you can know that, for example, if you have a fake food products or adulterated food products. Thank you very much. Thank you, Chiara. So last but not least, let's move on to Laura Crick. Okay, is that sharing okay for everybody? Yeah, looks fine. Thank you. Thank you. And so I'm Laura, PhD student in the St Andrews isotope geochemistry labs. And today I'd like to share with you some of our data from the Toba super eruption. So why are we interested in volcanic eruptions through time? We know that volcanic events can impact climber on both local and global scales. Perhaps one of the best examples is the eruption of Tambora in 1815, which led to cooling across much of the northern hemisphere with 1816 often referred to as the year without a summer. And that through time this potential effects on human evolution. The Toba eruption has been proposed to have caused a bottleneck in hominid populations at the time. However, this is still widely debated. So we need a continuous record of historic organism, and particularly for our work volcanic sulfate. So for this we turn to the ice core records. The ice cores are available from both the Arctic and Antarctic. For example, we have the sulfate records for an emberg in Greenland and sulfate from EDC in Antarctica. And we can see that volcanic events are easily distinguished above the background level of sulfate as these peaks. So this gives us continuous record of volcanic sulfate going back 800,000 years in Antarctica and 110,000 years in Greenland, making them an ideal record for looking at historic volcanism. We also note that we see several of these bipolar peaks in the course where sulfate is apparently deposited simultaneously at both Arctic and Antarctic latitudes. So there's two potential mechanisms for these bipolar peaks. The first is if we have a large tropical eruption sending material high up into a stratosphere, where it can be distributed globally and deposited at both poles simultaneously. However, we'd also see a similar signal from two extra tropical eruptions happening within a small time frame, and then apparently depositing at the same time. So we can distinguish between these two scenarios. This is where we turn to the sulfur isotopes. So if we follow this schematic, if we have sulfur aerosols erupting into and above the ozone layer, they're exposed to ultraviolet radiation. This irradiation causes the aerosols to undergo photochemical reactions, and these reactions induce a mass independent fractionation or myth signal into the sulfur. The signal is then preserved in a sulfate into positive ice cores. And both the ozone layer, this myth signal is not signal is non zero. It can either be positive or negative, depending on the phase of the eruption. Whereas we'll also get sulfate in the ice cores from extra tropical eruptions. And these events does not reach the ozone layer and isn't exposed to ultraviolet radiation. It won't inherit this myth signal, so which will be approximately zero. So we can use this mass independent fractionation to differentiate between these two scenarios. So we've applied this to the top of eruption. The top of crater is located in northern Sumatra, Indonesia. And about 74,000 years ago, it underwent one of the largest eruptions of the quaternary period, and we can see the resulting crater lake here. And multiple sulfate peaks have been identified in both Greenland and Antarctic ice cores, these bipolar events within the age estimates for the tober eruption. So we have measured the sulfur ice topes for 11 of these potential candidates across two Antarctic ice cores, EDC shown here, and also the EDML ice core. And from this analysis, we have identified peaks that contain only tropospheric sulfur, which are indicative of these high latitude smaller eruptions. And then we've also identified three sulfate peaks that contain only stratospheric sulfur. This is characteristic of a large tropical eruption, therefore making these the most likely candidates for the tober event based on our data. But we've also measured the largest magnitude myth signal that has been recorded in volcanic ice core sulfate to date. And we have a potential climatic impact of tober. If we look at some other paleoclimate records from this period, we have the oxygen isotopes for the n-grit Greenland ice core in red and top panel. And then the oxygen isotopes for the Yankal speleotherm here. And we can see over this time period, they're undergoing these significant fluctuations. When we're interpreting these records in the Greenland ice cores, this correlates to cooling and warming events in Greenland. And then in the speleotherms, this indicates changes in the Asian monsoon. So if we look at around about 74,000 years ago, the time of tober, we see we're moving into this cooling period in Greenland. And if we plot our most likely candidates for tober based on sulfur ice tobes, we find they actually lie on this transition into the cooling period, suggesting that although they may not have caused this cooling in Greenland, they may still have accelerated or amplified this event. So though we've successfully managed to narrow down the tober candles, there's still more work that can be done using the ice cores. One of the first things we could do is measuring the sulfur ice tobes for these same candidates in Greenland ice. See if we see the same myth signals, particularly the large magnitude events. And also identifying tephra shards in ice. When the shards are preserved, we can analyze their chemistry and match them to their potential source eruptions. And when considering sulfur preserved in ice in general, we're also looking at the diffusion of sulfate through ice and how that may affect the sulfur isotopes, tens or hundreds of thousands of years after they've been deposited. And finally, the incorporation of volcanic plumes into photochemical models and how the import of large volumes of sulfur aerosols high into the stratosphere may be affecting the atmospheric chemistry. Thank you very much for your time. I look forward to questions. Please feel free to get in touch with any other questions and we have a research article in climate of the past in review currently for further information. Thank you. Thank you, Laura for that nice overview and to all three of our speakers we've got three fascinating very different topics there. So, as I said before, if you've got questions, the easiest thing is just to drop the letter Q into the chat box, and we'll go to you for questions or you can of course type your question out and I can read them. We have already a question in for Christine from Jonathan Amos. Jonathan, should we go ahead to you? Are you able to unmute yourself? Yeah, yeah. Cool. Yes. Can you hear me? I hope so. Yep. Excellent. And for Christine. Christine, thanks very much for doing this. Some quick questions, which I hope are one word answers, and then something that will require a little bit of explanation. Sure. What is the, what is the distance from the Ellsworth Mountains to the current ice edge, and also from the Ellsworth Islands mountains to the drill sites, the Jody's resolution drill sites. Do you know those numbers? I know them in general. It's about 1000 kilometers from the Ellsworth Mountains to the Shelf slope break, and then another 300 kilometers to the Amundsen Sea drill site. I will have to check the distance of the Ellsworth to the Scotia Sea, but I could easily email you that. That's very stimulating for us is the dropstones that we have found in both of these different locations. Those sites are 3700 kilometers apart. It would require, from what we understand of the oceanography, icebergs to float off the Ellsworth range in different directions, bearing the same type of rock and drop them to the seabed. Right. Okay. The West Antarctic ice sheet would need to have been considerably reduced in extent between four and three million years. The mid-placing, so the current sort of Amundsen Sea ice edge, you know, the front of Swates and Pig, that is about 1000 kilometers away from Ellsworth Mountains, yes? Yes, from the range itself. Okay. In the picture that you showed, did you show some of this green sandstone from the mountains? Yes. And what I showed was a dropstone that appears in the sediment cores. And I can show that again for a moment by sharing my screen. Okay, so I won't go to the full extent, but amazingly the dropstone that we have is quite small, but it yielded hundreds of zircons, so we have very robust information from isotopic information from those special types of sand grains. Okay, so isotopically, they're a distinct match for the sandstone to Ellsworth. Yes, and we're using two indicators, not simply just the zircon age, but we're also using appetite, fission track information. And based on that line of evidence, we feel that the dropstone that we recovered is from a deeper level of the Ellsworth Mountains than is today exposed above the ice sheet. Okay, the final question that requires some explanation, I guess, here is, you know, snow falls on the mountains. It compresses into ice and it runs downhill towards the ocean. You carve icebergs and eventually they'll drop those stones somewhere out in the ocean. Why couldn't these dropstones have just been, you know, a long track journey that started high up in the Ellsworth Mountains when all the way to, you know, kind of, I mean, I know this isn't the case, anyway, all the way to the edge of Swates where it is today, calves, and then travels out with the iceberg. What is it that enables you to say, there's no way in the mid-Pliocene that that rock could have got out to that location in the Southern Ocean, unless West Antarctica, as we know it today, wasn't there? Yeah, this is a fabulous question and it does have to do with the nature of that dropstone in as a sandstone of, you know, aggregated grains that are reasonably cemented. But in our view of observations from that material, it would not withstand a great deal of transport with deposition and then re-transport over multiple steps of the cycle. Furthermore, it probably would not hold up well to a great deal of interaction between the ice sheet and the bedrock. It would be destroyed and disaggregated. So we believe it was floated on an iceberg that originated in alpine glaciers of the Ellsworth Range. Here's a quick map, but to produce debris late in icebergs, they're needed to have been somewhat wet-based and channelized glacier streams in alpine topography, potentially with a tidal glacier expression of the type we'd see in southeast Alaska or British Columbia today. And we think that these green sandstones could only withstand this sort of local transport, not survive through multiple cycles to travel from the Ellsworth Mountains out to the mouth of the Amundsen Sea or north to the Scotia Sea. Fantastic, yeah. And you date their deposition in the muds out in the ocean, yes, to get when they were deposited. Is that right, yeah? Yes. Do you date the muds? Yeah, there's a very strong continuous chronostratigraphy from the actual drill core themselves. So we know the age of the sediment that the iceberg-rafted material resides within. Thank you so much. It's really kind. Thank you. And please do take advantage of the materials that I uploaded to the media site. Thank you. Thank you. Thank you. So we have another question for you, Christine, coming in from Julianne. And they say, knowing that the West Antarctic ice sheet must have been drastically retreated millions of years ago. What does this mean for today when we are confronted with climate warming? Do your findings confirm the fear that the ice sheet will disappear completely? Okay. Our findings do confirm that the ice sheet can disappear fairly rapidly and also that it can reestablish itself fairly readily. I'm aologist of the sort that I am. Three or four or five million years is incredibly recent in time. And we read from very detailed records that we're striving to make more detailed that the ice sheet has collapsed back in a considerable extent, specifically in the middle pliocene. There's an interval if we read current literature from climate modelers that we may be entering within the next one or two decades. The climate conditions of the pliocene are what we are expected to enter. And if warming continues at the rate that it is now, we may stay there. We're very intensely interested in these sediment records that can reveal to us what the situation in Antarctica was like at that time. Thank you for that question. Okay, thank you. Onto question now for Chiara. And this is from Sarah Darwin. Now that you've mapped out some chemical signatures of extra virgin olive oil. Is there a way to do a quick onsite testing without a clean room. I'm imagining that a quick test would be useful for those purchasing olive oil. Okay. So, to answer one related to the onsite test and one related to the clean room. Generally, the onsite tests are related to macroelement or for example like smell, but you can't know the, for example, small differences, because in this case, we wanted to analyze different kinds of extra virgin olive oil from different regions. On site, you are not able to distinguish this very small quantity with the test onsite. And you have to use chemical analysis in laboratory. Generally, the laboratory not have a clean room. For example, in Italy, there aren't a lot of clean room. But all the university, for example, analyze the food products. There are a lot of cases related to food products, but they don't have a clean room. They have only a spectrometer and ICPMS normally, and they analyze the food products. In this case, it depends on what we want to do and to understand because, for example, in this case, the clean room give you, you are sure to know the very small differences and you are sure that what you analyze is what there are in the samples. And there aren't, for example, adulteration to the environment or rather what you analyze on the spectrometer in a clean room is really what you have in the samples. But it depends on what you have to do. Yes, in the clean room, it's not so important. It depends. But onsite, test onsite, with the test onsite, you aren't able to discriminate these very short differences. Okay. Thank you. Thank you. So, Sarah Darwin has another question. This time for Laura. And Sarah says how long does it take to transfer ash from a tropical volcano to make it to polar regions. I'm wondering about lag time and correlating eruptions with signatures in ice. Thank you. Thank you very much for the question. So, yes, when we have sulfur erupted from the tropical volcanoes into the stratosphere. Certainly in the case of the sulfur aerosols they have resident times of sort on the order of months to years. So it may see a delay in perhaps a month or so before sulfur starts arriving at the poles and then it'd be deposited over a sort of several months period, depending on the size of the eruption and the sort of the amount of sulfur that's actually been erupted. And I would imagine a similar mechanism will also affect the sort of particular ash and things as well. So yeah, we will see a very slight lag to in the eruption and actually showing a very nice cause that when we source working 10s of 1000 years in the past. That doesn't really make as much of a difference, but it certainly applies to more recent events like, you know, Tuba and Tambora. Thank you, Laura. Yeah, and Sarah says faster than faster than she thought. Any further questions for our speakers today. Christine so she's she's got to pop off but I'm sure Christine is available via email for more questions of course so please reach out to her. Thank you very much everyone. Nice to be here. Bye bye. Good to have you. Thank you. Okay, any more questions for Laura and Chiara. If there's no more questions, we will leave it there and say a big thank you to our speakers for those really interesting topics. As I said before, please reach out to our speakers via email. I'm sure they'd be happy to be contacted and also there's lots of really useful information in the press center of the eG website. So feel free to head there and and there are more press conferences tomorrow afternoon as well.