 Good morning everyone and welcome to the third press conference of EGU 23, which is the annual meeting of the European Geosciences Union. I'm Jillian D'Souza, I'm EGU's media and communications officer, and I'm happy to introduce you to our wonderful speakers who are joining us today. They have their research and abstracts have been shortlisted out of 17,000 papers that was submitted this year for the meeting. So that's very exciting. And they are going to present some of the most unique findings in the Geosciences with you today. So each press conference will have time for the speakers to make their presentations individually. And then we will conclude in the last 10 to 15 minutes with a media question and answer round. For those of you who are joining us virtually, I ask that you mute your microphones until we get to the Q&A round at the end. Now I'm going to go ahead and introduce our wonderful panelists for today so that there's faster transitions between all our press conferences titled humans, humanoids and extraterrestrials. Our speakers today are Tharas Garia from ETH Zurich, Institute of Geophysics, Department of Earth Sciences. Then we are joined in the center by Jill Ramstein from CEA Sackle, LSE France. And finally by Thomas Litt from the University of Bonn, Germany. So welcome again and we are ready to have their presentations. The order for the presentations however we will be listening first to Tharas followed by Thomas and then from Jill. So hope you enjoy today and thank you again. Over to you speakers. Okay. So here is our work with Bob Stern from UT Dallas, and we are working together on trying to understand relationship between life evolution and platyctonics and we believe that findings from this work, they're helping to understand the well known paradox of missing civilization so please next slide. It's well known that no any extraterrestrial civilization is communicating with us, and we are wondering why. So, the take home message from our study is that the reason for this missing civilization see that they can only be expected on planets with ocean continents and platyctonics. And these planets are extremely rare, and you know can be expected as this probability of much less than 1% among the habitable planets with primitive life. Next slide please. We need platyctonics platyctonics is needed for accelerating the evolution of complex life. So in general, life evolution is extremely slow on Earth. It took more than three and a half billions of years to develop our civilization. And then, of course, any processes that are speeding up the evolution they're playing very important role. Platyctonics what it does first is suppresses extreme volcanic events, which become less frequent because heat is released in a distributed long term manner along the grain boundaries along the plate boundaries and second what it does it produces continuously changing and then stimulating environment for species to evolve so it stimulates biodiversity and more importantly it operates on the time scales of life evolution so not too rapidly and not too slowly. Therefore, we need platyctonics and platyctonics are very rare among the terrestrial planets. So there are probably many planets which are hosting primitive life, but they have little chances to evolve into complex life. So please next slide. So why oceans and continents are needed. It's to provide optimal environment to evolve from simple life to complex life and finally to intelligent life and civilization. So, oceans are good in hosting primitive life and protecting it from, for example, radiation, providing structural support, providing optimal distribution of nutrition, but then continents are needed for complex life to, you know, experience this relatively hostile environments, which stimulates many aspects to develop complex appendages, for example, you know these opposable fingers of primates and so on. And this, in fact, also a good environment for exploring fire and electricity and to finally develop intelligent life and civilization so on a planet if we would like to move from primitive life to complex life and populations, in addition to platyctonics we also need this continents and ocean to coexist for very long time, during the entire planetary evolution. And this is again, a rare to be expected. So please next slide. So what we suggest on the basis of our research is to do the following if we would like to compute how big is the fraction of planets with life, which can develop into intelligent life and civilizations, we have to multiply two probabilities. So we have to multiply probability of such a planet to host continents and oceans for a long time, and the probability to host platyctonics for a long time. And both probabilities are very low, and then the product of this multiplication is even lower, it's much, much less than 1%. So in our galaxy there are many planets, they start at different times with their star system and they develop through time in parallel with each other. Many of these planets they have good conditions for life, and many probably develop primitive life. However, only very rarely, these planets they can have continents, oceans and platyctonics, which help developing intelligent life and civilizations. Probably, there will be some civilizations before us, or there will be probably some civilizations after us, but they are so rare that they do not cross with our communication window. So we are from this prospective doom to be alone. So next slide please. This is the final slide if you're interested to learn more about relationship between life evolution and platyctonics. So please watch this five minutes video recorded by Bob Stern on YouTube, where he presents results from our team of researchers working on the relationship between life evolution and platyctonics. Thank you for your attention. Thank you, we will now hear from Thomas, whenever you're ready. Good morning everybody. It is well known that the cradle of modern humans is situated in Africa, with the oldest evidence around 300,000 years before present or 200,000 years before present in East Africa. And this is also well known. That's the first occurrence of modern humans as a rival in Europe, who plays around 450,000 years ago. And the Levant corridor is a very important route record for the expansion and migration to Eurasia. And to highlight what I would like to tell during this eight minutes is that we have one several occupation phases of modern humans in the southern event. And as a very important result of our study and investigations, we have the first continuous vegetation climate record of the southern Levant based on a Dead Sea drill core and compassing the last 220,000 years means this is our archive where we are able to reconstruct the climate system and even the environment. And we observe based on this climate record that we have green corridors between Africa and the Levant during warm and humid phases which we can identify. And so, finally, the Levant is a huge area with a mixture of ecosystems and sufficient water availability. You can say this is the Garden of Eden for the modern as a modern human when he arrived Eurasia. Okay, let's start with this geographical map and the Levant is the only permanent land bridge between Africa and Eurasia to bring the quaternary. And as a present day Sahara and southern Levant, which is Sinai and Negev desert is a barrier and during these climate and environment conditions, this is impossible to move from Africa to the Levant or to Eurasia and green corridor is necessary for the migration of the modern humans. This is when and why. And here, you can see the first evidence of modern humans, the Missilia cave around 180,000 years up to 190,000 years before present. Then last warm stage interglacial stage, 120 up to 90,000 years BP the school and cut sea caves. This is a quite older record well known and Mano cave pretty new 55,000 years BP and from the polygenetic point of view this is a type which arrived successfully Europe, Asia, and even America. So this means there's no continuation from this first record up to these Mano cave record. Next and that see from the geological point of view of fascinating area. This is the boundary if you want between the African plate at the West and the Arabian plate at the east. And you can see the Dead Sea basin and more to the north is this is Sea of Galilee. And these are excellent archives for paleo ecology and paleo climatology. By the way, the Dead Sea shore area is the lowest point on the Earth's surface worldwide with minus 420 meter below the recent sea level. We obtained course based on an international dream campaign under the umbrella of the international continental scientific drilling program. And we used a barge system, by large, the so called deep lake drilling system, and we obtained course in the northern Dead Sea basin in water depths of 300 meter, and we obtained course up to 450 meter sediment and compassing the last 220,000 years. So this means we have all these expansion phases of modern humans in this record. Poly analysis is based on several reasons, one of the most important paleo ecological method to reconstruct environment and even climate. We took samples from this core, and we have to prepare these samples with chemical treatment to remove mineral particles and so on, for example, HDL for calcium carbonate or even HF quite dangerous to remove all these mineral particles quartz and so on. And then we concentrate the residue and under the microscope we are able to identify pollen and the advantages pollen do not decay in lake sediments and she can be preserved over 100,000 years even million years and so we can really see which plants grew in the surrounding area and plants cannot move as they are at balance and equilibrium with the climate parameters like temperature or precipitation, and we can use these relationship and at the end we have a calculation and interpretation of these record based on point diagrams to see quantitative changes of the vegetation type, and even the amount of special plans can be observed based on these calculation. At the end we use the knowledge of the vegetation history, simplified above this diagram only the relation between trees and shrubs, but we have the whole assemblage of the evidence of plant species available and we calculate this based on transfer functions as a statistical method we developed this method together with meteorologists and one, and we are able to quantify the, the relationship between plant distribution area and precipitation or temperature as you can see the winter temperature, you can see we have changes of the system through time. We have more mild winter temperatures, which can be observed in this diagram. And if you have a look below to the annual precipitation you can really see peaks of higher phases with precipitation based on these pollen record. And this is not surprising, I would say, but we are happy to see this correspondence between the occurrence of modern humans in the Levant, which are clearly related and connected to more humid phases means we have a corridor. The corridor was open, and the Levant was like a bridge. And then this is the case for Miesli as the oldest evidence, Khafzi and school for 120,000 up to 90,000 years and finally the last migration wave with the Manu cave, which was successful even for expansion and migration to Europe. Some aspects of the results has been published in this book, I was the responsible editor for that. You can have a look to these at the desk of Schweizer Bart, Schweizer Bart is present here, but I have some flyers with me and the book as well. If you're interested in. Thank you so much and equal attention. Thanks to us. And now we will move on to our third speaker. So Jill, we are just loading your slides and. Okay, you can. Yes. Okay, we have your presentation slide is just to say that today, I'm talking to you. I'm here alone. This work is a work of maybe 50 people for four years. We include paleontologists that mean people working on bones. Palinologist has my colleague say to working on Poland climate models. Working on climate as myself and niche models that are interested in dynamics of population. The next slide is to introduce what are the problem we want to cope with. We are interested to show that, in fact, the dispersal of our ancestor, especially the apes during Neo Gen Neogen is a period from 25 to now is mostly due to the climate change. So you can see Africa, what happens over Africa during that time period. So as my other colleagues talk about there is tectonics and tectonics modified drastically. Europe, Africa and India, and one thing you can see here is a string gauge of the apparatus if you were an extractorist, and you come to the on the earth, 14 million 15 million years ago, for instance, you will see that a huge, huge sea was covering east of Asia and west of Europe. A really cat of this you'd see is Mediterranean sea today. So when this ice when when this sea ice retreat little by little, it changed completely the climate of Asia, Africa and Europe, why, because you get a super big continents with eating in the summer. This leads to monsoonal climate. This is a very important changes and I will show all this impact drastically on our ancestors. Another thing is, and you can see that a good place to see that is the Chad Lake that you're here to have here, and the Chad Lake become very, very big in the humid phase of what my other colleague told you about, when there is an ice, the Chad Lake become as big as France, 400 square kilometers, 400,000 kilometers, and when it is, it is very narrow, it is just like today. And so there is large and huge differences. And the last thing is a uplift of the African realtor. So this has a tectonic events and I'm very glad to speak the third, because I can use what my friends said before, the tectonics modified the African continent and because of the tectonic, the climate was also modified. So the next slide is to show you where we have found today, over the Chad Lake to ominates. This slide is very famous to my seven million years ago, and the author is Abel 3.6 million years ago. You can ask you why they were living there was it possible to live there. And the result of our study for concerning a strong because is the next slide. We are able accounting for geology and accounting for climate. We are able to compute the climate of the of this period, and we are able to, to show the suitability area. So this is the fourth slide. You see here, the suitability area as predicted by climate model and niche model. And you can see there that the suitability area for us to austral pittages are exactly where we know where they are. They are in South Africa. They are in the eastern corner of Africa. And they're also because the climate was completely different around the Chad Lake. But the most important result of this first part of austral pittages is the next slide. During four and three million of years. So the tectonics is no more important because it is just one million of yours. What is important is what my other neighbors say it is the precession, the fact that there is a humid face and dry face. And what we can see here, which is the main result is all these austral pittages can move, can they move from the eastern corner of Africa to South Africa, can they move to the eastern corner Africa to the Chad Lake. So we see here that depending on the precession cycle, there were period where there were it was possible to go from eastern Africa to South or from eastern Africa to the Chad Lake and period where it was completely impossible. But also we can show also what are the refuge area, the place where you can always live, because the condition remains favorable. So this has been published in global and planetary change. The first author is jibbert and now I will go to another big trouble this time. And this travel is a struggle. The apes is big monkey that means gorilla, orangutan chimpanzee. You can see on this slide, this slide is a slide with four little panel. The nest of this ape begin at the beginning of the neogen it is 23 million years ago. And what you can see is that, okay, what is very easy for us to simulate. And it is to simulate the trouble they did. All can we do that. We have not any ominates in your computer. No, but ominates they need fruit all the year. So they need to live in forest tropical forest. And that we can simulate the climate condition favorable for forest so we can follow the forest. And so we can follow the following the forest, we can know where potentially where they can go. So what you can see here is the saga of the apes they live in tropical Africa so we're very happy there. No problems that get food all the year. Well, the climate begins to cool, but there was a reversal, which goes mid myosin climate optimum. And that's 17 million years from 17 to 15 million years. So the tropical forest invaded Europe, and you have Poland record that show that there is a large extension of tropical forest. So the apes they get out from Africa they get out from Africa the same story, but a bit older during this period, because the material forest and tropical forest get in Europe to Europe, and we find Poland and bones that are consistent with that. Unfortunately, the climate, they continue to cool and cool down. And so they have to leave Europe to go to Asia, and now they're from seven million years only in the southeastern area where they still leave. So, can we understand this, this big journey of the apes. The next slide is showing you climate results. So what do we need in terms of climate we simulate the climate. Thanks to the techniques, and thanks to the orbital forcing we can compute the climate of the mid myosin. This is the result that you can see here on the top you can see the temperature what do we need to get tropical forest over Europe. We need to get warmer temperature and this is what we get in our simulation. We get warmer temperature for me myosins and present. Okay, it's not enough. We need a seasonal cycle which is very done, because if it's frozen in winter, no tropical sun. So you see on the panel that the seasonal cycle is largely done during myosin. It's not enough. You need a lot of water to get and to sustain tropical forest, and we show you that we get that winter by precipitation we can simulate a climate, which is consistent with that. So the next slide is what we do with this climate. We force the vegetation dynamic model. And what we see here and what you can see on this slide, it is a vegetation change. And as quick and expect, and as we know from the panemologists record, we have indeed tropical forest in this area from our climate simulation. So the important result here is to understand that the AIDS they don't decide to go out of Africa. So climate made it possible and they did it. This was the first time they get out from Africa and then after due to the cooling, either they go back to Africa, either they decide to continue their lives and victory to southeastern. The last, not the last, the next slide is the main result of the second part. We are able to understand something which is much more difficult to come to understand on the on the left side, you have the niche modeling for 1717 million years ago that mean before the big trouble. You see that the niche model told you that the apes are restricted to the eastern corner of Africa, which is true. This is where we have, we have, we have bones and and everything we, we need to know that. And then you see what happened three million years later, 14 million years later, they are outside of Africa, they are in Europe, they are in India. So what happens on the right side, you can see that what happened, they go outside from Africa and it is long period of time. So they are also have time to adapt to different planet. The niche modeling is not completely rigid. And what you see on the right side is that the niche modeling of the of our ancestor 14 million years ago is not the same that the niche model that the niche of the of the apes 17 million years ago. So what we can, the main result here is that we can understand why they get out of Africa, why they were obliged to leave Europe, and also, how much they were able to adapt from East Africa, their nest to European climate. And the last slide is just a kind of joke. You know this very disciplinary study, our long study you have to discuss with people very different. You get students that that are obliged to learn a lot. And they are very good. And I hope they will get a permanent job. Thank you very much. Thank you so much to all our three speakers. I think we can all agree that you are telling the same fascinating story but from different perspectives and different time periods so we truly enjoyed that. We will now move on to the last part of our press conference which is the question and answer round. So I now open the floor to questions from journalists. If you are in the room and if you have a question, please raise your hand I will give you the microphone and then you can introduce yourself, your publication or affiliation and then ask your question. If you are joining us virtually then you can you have two options you can either type in your question in the zoom chat, or you can use the hand raising function and we will unmute you and you can ask your question. So over to you now. If you have any questions coming in for our speakers. Okay, we have one question from a journalist in the room. Thank you for all your presentation. It was really interesting. I have a question, especially about Asia, which is, I don't know, a bit more. Oh, sorry, yes. So I'm Nicholas and I'm a student journalism in the University of Paris. And so I used to work on a new species found in the lack in Kalao's Island, or more than insist that was found around five to 10 years ago. And so I was wondering, do you have any insight of how they would be capable of traveling the sea, which is like, which would be the first like appearances of traveling the sea for humans. What interest would they have in terms of climate since they wouldn't know what climate it looks like it looked like in Asia. Do you have any idea of how the species was moved to Asia and how the climate would be favorable in this period. I don't have the idea of what time exactly they left. I just forgot like the time scale, but you have any idea of how you have this transition from Europe or Africa to Asia. Thank you. You didn't say any word about the period you're talking about. So it's very important for me or Thomas to answer your question. I think the fossils was were found from bones of around 50,000 years ago. It's like the first hypothesis was it was a home of from the floor asylum or senses. And so then later they found that the fossils were a bit older than these ones. And so that's, that's why they came up with this hypothesis that it's a new species. Okay. Yeah, the florist type. But I'm not an expert. I'm not a polyanthropologist. Anyway, this is really an own species with old roots. And then modern humans came to Asia around 100,000 years 80,000 years BP, and they reach by the way, Australia, around 60,000 up to 80,000 years BP earlier, much earlier than in Europe. That's interesting to note. Now, but anyway, the extinction of these type, ancient type might be related to the expansion of modern humans. You're right. In fact, depend. This is why I ask you the question of time, depending on time the response are quite different. For instance, what I told you about the eight saga. This is million of years that mean that the retreat the shrinkage of the paradise is enormously important for instance for them to go to Asia. It was, but this is a time about million of years now you're talking about something completely different. You are talking about 50 kilo years, then it's completely different story. So there is a landscape model that are able to more and more correctly reproduce the landscape nearby the place for instance in Asia, where you find your, your, your, when you get your finding. These people that are able for the climate model, the landscape model with climate for erosion and for local techniques, and they are able to tell you what kind of way what kind of pathway that are, they can take to reach the place where you find it. It is obvious that they don't swim. They don't go there. They don't cross water for for kilometers. So you have really to have a landscape simulation as accurate as you can, of the period to try to understand how they can reach this place. Very often, you get the idea, oh my God, all they were, for instance, those child like all they were here in the chat, because it has completely changed not only the climate, but the landscape to. So this is, this is a short answer to your question. He answered quite correctly to the question. You know, they're almost up here and they, they, they go from Morocco 330 kilo years before present Australia 60. And when they did they go to North America and Europe, North Europe, for America, it was only 18 kilo years why, because there were a huge ice cap. It's impossible to go there, except during interglacial very short period. So there are always very good reason why they don't go there it's just because it's just non suitable it's just impossible. And this is the reason why you get them going from Africa to Asia but not a very few to Europe and not at all North America and Canada. You have to take into account the present day situation geography and the paleo geography, and during the last ice age, which does not affect by glaciers in Southeast Asia, let's say it was not cold. But anyway, caused by this huge ice volume global ice volume, you have an enormous setback of the sea level minus 150 meter in comparison to today. And so Sunda chef became dry and they could really walk and send some in the hoping to reach, let's say, Australia, but this is a narrow time window. And the orbits, for example, these were typical in the population isolated and became in small. This is by the way I'm a paleontologist. This is quite common in history, even with elephants. And Sicily, nice animals, so the size and the same isolation now and then reduction of the growth. And it's generally the rule for, you know, terrestrial population that they are much more strongly shaped by the tonics and landscape and climate than, for example, marine population because marine populations are much better interconnected so it's more diffusing environment they can travel better, but terrestrial population they have lots of barriers and then, you know, they really shaped by this landscape and tectonics and climate evolution. Okay, that was a very nice discussion from all speakers. We have another question coming in. Hello, my Javier or was and I'm a freelance journalist. I have a question for Tara's on the first person, how do you estimate the amount of planets out there with oceans like the turning sense or what do you look at to know a number. It does sound a little bit like Earth centric your analysis. How do you account for things that we might not imagine could be possible. Thank you very much for these questions. I was hoping that somebody will ask question about quantitation because I am the person who does quantitation. There is very famous Drake equation. So the sense of this equation is the following. So we have to rely on our communication window, which can have, you know, certain duration. And then, since planets are starting at different times with their star systems, essentially, we can estimate how many planets will be at approximately the same stage of the revolution. We see now a galaxy by taking into account rate of star formation and the width of the window. The most stars we form in per unit time and the biggest our communication window, the better the more planets we can essentially observe. So this is our basics. And then what people start to estimate is how likely is for each star to have planets, how many of these planets can be of terrestrial tie and have water, how many of these planets can potentially host life. And then this is where our study comes in. So if planet can host life, how big is the probability that this simple life will develop into the complex and intelligent. So our conditions that we put on top of this ocean and continents, for example, and this is very restrictive condition, why is it restrictive, because you cannot worry amount of surface water too much. So if you have too much water, then it's just brutal continents, there is no continent, so there is no erosion, no delivery of nutrients into oceans and so on. If you decrease amount of water too much, then essentially what you will do you will expose so called mid-ocean ridges, which are one of the products of plate tectonics. So the migration of the ocean flow at mid-ocean ridges will be suppressed and this will kill plate tectonics. So again, if we connect ocean continents and plate tectonics, this will create unsuitable conditions for plate tectonics. So then we are sitting within a seam range of how much water is needed to be at the shore. And the trouble is that planets, when they form, they don't care, you know, how much water is delivered. You can deliver anything from you or the drywall to ocean wall. So you can create something like Enceladus or some, you know, other isocetylites and then there will be 50% water. So 50% water will never allow for coexistence of oceans and continents because everything will be flooded since, you know, topographic variations are even, you know, independent of the planetary side. So then what you have to do to compute this probability, you take your range which is allowed and then you divide it over the range which is expected. And then you get very small number because you are trying to reach some kind of Goldilocks condition. So you really aim at very teeny amounts of variations, and this is not possible from the planetary perspective condition to be kind of self regulated. Again, there are conditions for plate tectonics, which, you know, permit this process on the on the planet of terrestrial type. So one of them is of course availability of water, but then in addition to them, certain planetary composition certain planetary size. Again, if you look for variability, and then just compare your expected range of, or your permitted range of variation with expected range of variations and again get very small number. So this is how one can come to these numbers initially we will not even believe in that these numbers could be computed. There is very good literature in astronomy and in earth sciences which were these questions are discussed, and then we can come with some quantitations. But of course, these are not the only factors which may affect life on a plane. There are other factors such as presence of magnetic field and so on. So expectation will be that you can only decrease probability of civilizations with adding more factors because then you will find less and less and less planets where these additional conditions will be satisfied. And then in the end, in fact, we will have less and less and less civilizations to be expected. But on the other hand, as my colleague Bob Sternes is telling, are we really looking for planets with civilizations or other planets with primitive life, which we can then explore and populate. So perhaps we don't need civilizations because who knows what is going to happen. I may I may add something much more terrestrial and climate. You know, honors the climate, the life is there from 3.6 million of years that mean that the climate has always been suitable. We have been frozen but not so long. Most of the time, the climate was favorable. And one very little thing that is very important in fact is that we have a big satellite, the moon, why is it so important. It's very important because the moon, just because it is there is as for effects to to make the obliquity of our planet, very stable, and an obliquity very stable is a very good condition for climate very stable. So only, only here on the earth, we see that we have conditioning as my colleague say tectonics of course many condition. But moreover, we have the chance to that there is because this big this big collision for 4.2 billion of years that creates the moon and the moon as a very beneficial effect on the earth by the way, you know that the obliquity in Greek. It means climate. This is what the world come from. So there are many, many conditions for life to sustain for a million of years. As my colleague say, galactic conditions, but also more planetary condition and climate that makes it possible to develop for many, many, many million of years. Thank you. Do we have any more questions? I don't seem to be any questions from our virtual attendees either. So if there are no more questions from journalists in the room, I think we are ready to end our press briefing here. Thank you again very much to all three speakers. If you would like to have formal or informal interviews or chats with the speakers, feel free to reach out to me and I will be happy to put you in touch with them. Throughout the EG 23 week, the entire recording of this press conference will be available later today so you can refer to that on EG use YouTube channel for more reference. And I would also like to add that if you're sticking around we have our next press conference at 1130 today. The title is early warning for extreme events, earthquakes, droughts floods and livestock disease. Some of you there and thank you very much again. Thank you. Thank you.