 We'll kick off now with the fourth press conference. This one is titled from Avalanches to Aviation, The Sahara's Global Impacts. So good afternoon and welcome to VEGU 21. This year's virtual annual meeting of the European Geosciences Union. This year we've got more than 14,000 abstracts and 16,000 people from across the globe participating in this meeting. I'm Erin Martin-Jones, this year's EGU press conference assistant, and I'll be hosting today's session, which will include a question and answer period following presentations by all three speakers. So to allow members of the media to ask your own questions, we're conducting this as a Zoom meeting. So once the last of our three speakers has finished, please either drop your question into the chat box or the letter Q, and I'll come to you to ask your question, or equally I can read out your question if you'd rather. So hopefully this doesn't happen, but if for some reason Zoom suddenly quits, we will restart the conference, give you a few minutes to rejoin. And likewise, if you have problems at home with your internet and you have to rejoin the session, that's absolutely fine, there'll be someone to let you back in. There's a lot of really useful information on the online press center for EGU, so that's media.edu.eu and you'll find all the abstracts and other documents relating to these press conferences up there. So please have a look there. And so I'll introduce our three panelists for this session now to make for faster transitions in between times. So for this Sahara themed press conference, first up we have Dr. Marie Dumont, who is director of the Snow Research Center at Meteor France in France. Secondly, we have Dr. Athania Sos Votis, Votis, sorry, who is senior researcher at the Finnish Meteorological Institute in Finland. And last but not least, we have Dr. Sarah Besart, who is postdoctoral researcher at the Barcelona Symputing Center in Spain. So I'll now hand over to each of our speakers coming to you in that order to unmute yourselves and give a short presentation. And then after that, we will go to questions. So Marie, would you like to come forward first? Yes, thank you. So I'll start sharing the screen and I hope it works and you hear me. Yeah, we've got you in the slides as well, that's fine. Okay, great. So good afternoon, everyone. I'm happy to be here. So I'm Marie Dumont. And on behalf of my colleagues in Coater, today I'm presenting some new results that we have shown at EGU on the impact of Saharan dust on snow. So here in the background, you have a peak which was taken in February this year after a huge Saharan dust event of early February and it's showing really orange surface, which in fact is snow. So that's typically the type of event we are looking for and also the impact of that type of event. Events and on the right here, the peak is showing a slab avalanche. And I don't know if it's really visible on the screen, but this slab avalanche was triggered in February 2014. And you see the dust layer, which is just below the avalanche. And this triggers several questions. So what are the impacts of the Saharan dust event on snow evolution? And can such events impact the snow stability and the risk of avalanche hazards? So I can't change the slide. Ah, great. So the first thing we were looking at is the impact on the snow evolution and on the snow melt and duration. So the primary impact of such deposition of Saharan dust on the snow, it's visible on this picture here. It's a really a change of color. So this was taken in April this year, close to my lab. And here's the orange snow is here. It's not contaminated by the soil. It is directly contaminated by Saharan dust. So it's really orange compared to the white snow here. And the main difference between the two is that the white snow is reflecting most of the solar radiation. So just incoming from the sun while the other, the orange snow is reflecting alpha of the solar radiation, which means that due to the dust, there is much more energy, which is coming in in the snowpack and which will lead to an increase in the temperature of the snowpack and then accelerant melt. So in one of our study, we were looking over the past 40 years of the impact of such events combined with other colored particles such as black carbon. And the impact of these particles on snow cover durations. And we were showing that over the last 40 years in the French Alps and the French Pyrenees, the deposition of dust combined with black carbon is responsible for shortening of the snow cover of an average 17 days. So that's quite huge in term of hydrological impact, for example. And for the event of this year, so of early February, we are now estimating that the impact at some place in the French Alps and Pyrenees is more than one month of shortening of the snow duration. So as I just said before, the shortening of the snow season is not the only impact of the Saran dusted position on the snowpack. The ones this dust layer is deposited on the snowpack, so it changed the color, it changed the absorption of energy and it's also changing the internal temperature profile into the snowpack. And this is really important because it's controlling the way the structure of the snowpack is evolving. So we ask ourselves a question which is often asked by mountain practitioner and also avalanche forecaster, which is, is there a relationship between the Saran dust event and an increased destabilization of the snowpack? So for this, we conducted several ensemble snowpack simulation with dust event and without dust event and we were able to show that under certain meteorological conditions, the dust layer is promoting the formation of a weak layer and then a higher slab avalanche. But this is not systematic, this is really highly dependent on meteorological condition and on other situation, it can also lead to more stable snowpack. The other effect of the dust deposition is that due to a decrease in albedo as an increase in absorbed energy, there will be earlier in the season more liquid work content in the snowpack. And this will lead to higher risk of wet snow avalanches problem I think on the right part of the slide here. So that's about it. And I can try to answer any question after the next talk. Thank you, Marie, for that introduction. So next up we have a video to show you from Athanasios, excuse me. I don't know, I notice that you are here in the audience. I don't know if you want to say anything in addition to showing the video. Not really, it is nice to stick to the plan but very nice to see you all here and they're very nice to see this exciting session. It's Sahara and something about this imagery is always interesting and important and exciting. So we can just go ahead. Thank you. Okay, so Fabio, if you want to show the video. Athanasios Votis and I will give you a briefing. Hi everyone, good afternoon. My name is Athanasios Votis and I will give you a briefing on how the dust clean project helps the solar energy sector to cope with sand and dust storms and the associated risks and impacts. I represent a consortium funded by the European Commission's Era for Climate Services Initiative which consists of the Barcelona Supercomputing Center, the Spanish and Finnish Met Services, Francis CNRS and Italy's CNR. I myself am an assistant professor at the Department of Governance and Technology for Sustainability at the University of Twente in the Netherlands. And I am as well a senior researcher at the Climate Change and Society group at the Finnish Meteorological Institute. As you can see in the picture, sand and dust storms can involve the transport and the position of tremendous amounts of mineral matter over large distances and geographical expanses with significant disruptions to society and the economy. Yet they are also part, an essential part, I would say, of the Earth's natural processes with their own geographical and seasonal patterns that relate in quite concrete ways and aspects to the industry. In dust clean, we have focused on aviation, which is presented in another talk by my colleague Sara Bassert and on solar energy. I will take you through in this talk our main climate products for solar photovoltaic panels. Our first product is the so-called transmissivity reduction or Soiling Index. It describes how much the energy output of a solar PV panel in percentage terms is dropping as sand and dust accumulates on its surface. We are providing maps and the necessary background numerical data that describe the annual and seasonal characteristics of this indicator. For the time frame between 2007 and 2016, at a 10 by 10 kilometers geographical resolution and based on a three-hourly time interval over that larger period, which is an unprecedented level of geographical and temporal detail in this particular aspect. As you can see, we are providing maps that cover the multi-year annual climatological, so to speak, behavior of the Soiling Index over different areas of the NAME region, meaning North Africa, the Middle East, and Europe. And we are breaking that down also seasonally, meaning we are providing the same behavior of the Soiling Index in winter, in spring, in summer, and in autumn. In addition, we are breaking down this information even further and we can provide more particular time series at more, let's say, detailed time intervals, not so aggregated for every particular location that you can see in these maps. Next, we provide the same kind of geographical and seasonal information for sunshine duration, which is an essential part of productivity of solar PV panels, which is also corrected for the presence of dust, which is not usually taken into account in other sunshine duration products. We combine this with the previously mentioned Soiling Index and also with other technical and economic performance information, such as electricity prices and cleaning costs. And with this information in hand and this approach, we provide a further product called optimal cleaning frequency, which describes how often in days a solar PV panel must be cleaned in order to produce electricity above cleaning costs. Currently, we give this information for commercial and for domestic sizes of panels. And as you can see, we provide the same level of geographical and seasonal or temporal information as with the previously described Soiling Index product. Finally, we provide information about investment and operational risk. On the far left and far right of the slide, you can see examples of how volatile the Soiling Index and sunshine duration respectively are in different regions. In the middle, you can see more details about the volatility of the optimal cleaning frequency if you zoom in into the particular time series in two exemplary locations near Barcelona and near Berlin. Thanks very much for your attention. We do invite colleagues from the industry to help us and partner up with us to develop version two of these products as we believe that they will add information that was not previously available to the industry and also hold a high potential for innovation, both technological but also broader societal one. For more information, don't hesitate to contact me at the University of Twente email address shown here but also refer to a recent freely available publication for an overview of the operational risks of sand and dust storms in aviation and solar energy and what sort of approach and wider mentality we take in developing climate services and products to help in this respect. Thanks very much on behalf of the whole dust claim team. Excellent. So as I said before, if you've got questions for our speakers, we'll save them up until the end. And so if we head next to Dr. Sarah Bezart, Sarah's about. Yeah, I'm here. Can you hear me? Yeah, I hope you can hear me. My screen. Yep. Yeah. Thanks a lot for the invitation and thanks a lot for visiting us in this different session. Let's say that the typical EGU sessions as Athanasius said, we are involved in one project that is basically trying to assess some services related to the presence of sand and dust storms and the risk that the sand and dust storms represents for some sectors. As Athanasius mentioned, the project is focusing in selected sectors and one of them is aviation. As you can see in this image, there are many of different impacts that we can identify in different countries, but also in different sectors of the society, not just related to health, but also some socioeconomic sectors as the solar energy transportation. And the focus today is aviation. But also there are other impacts as Mari showed related to whether climate or atmospheric chemistry. Then focusing in the part of the users, one of the fundamental things that you have to be in mind is how we distributed the dust sources at global scale. Thanks to models and also satellites, we can identify the most prone dust areas that are in North Africa, Middle East, and also in Asia. Then if you take a close look to the image, you will see also that some other sources in the South hemisphere, in Australia, in South America, and also in the states, in the western part of the states, in the Colorado region. Then it's something that is not just Sahara as a source of dust, it's a global phenomenon. And we are having this extra information coming from satellites and reanalysis, as I said. And this reanalysis is a fundamental tool for us for developing some services in sources because the lack of observations inside the desert is a problem that we can overcome with these modeling products. For dust clean, that is the project that Athanasius introduced before. We run a very exceptional reanalysis at very high resolution in the area of North Africa, Middle East, and Europe, where you can find the most important areas of dust emission. And what we did with this set, with this initial information is to understand the problems related with the aviation. As you can see here, we are described a little bit the impacts on aviation, and it's basically related with the high concentrations at surface level that you can find. And this goes the reduction of the visibility, and this reduction of visibility is related with the closing of airports. This means reroutines and cancellation of flights. Also, there are some disturbances in the airport operations. This means that the safety of the outside orbit are in risk, but also we have to clean up more frequently the wrong ways where the planes are using for day operations. In the image, you can see one event that was last year in Canary Islands, in Tenerife. And you can see how the visibility is a few meters in very exceptional events as the one that it is in this picture. The airport was closed during one day, and more than 700 flights were canceled because this single event. But also there are other impacts related with the mechanical of the aircraft. And they are related with ice crystals that can collapse the sensors around the aircraft, but also you can find other problems like the dust melting in the turbines or the turbine abrasion. As you can see here in this example, the famous Air France accident that was close, it was covering the route of Paris to Rio de Janeiro, was having the accident in the middle of the Atlantic. And some reports and some studies point that these ice crystal formation surrounding the sensors around the aircraft can be one of the reasons of the accident, not the only one, but one of the sources of the first initial impact of this accident. If we are thinking in long-term management planning, climatological runs are fundamental because it's giving us this behavior of the dust over sources and also regions around the desert. And this is an example for aviation. We are taking a look about how many times per day during a time series of 10 years, we were overpassing the threshold of visibility that the air was considered for safety. As you can see here, as we were expecting, the highest number of days is in the desert. But also surrounding the areas of dust emission, you can find days where this safety threshold is overpassed. If we move now to some more mechanical issues, as you can see in the image, the turbine exposed to dust can be very damaged if these dusts is accumulated for longer periods of fruits of traveling. And one of the things that we did inside Dasklin is to establish the dust exposure, the aircraft dust exposure index that basically is showing you how much dust is accumulated for a specific route. As you can see here, reddish colors is indicating the maximum level of exposure and is in the sources in deserts. But also there are some European airports where this exposure of dust is affected, the ones that are connecting Europe with Africa on the Middle East. I want to raise the question that there are a couple of airlines that are having the headquarters in the Middle East. Then the volume of these new airlines is growing and growing in the last years. And we will expect that in the next years, their business will grow exponentially also. Then this kind of information is very useful for them. But also if we move for a more short-term operations, there is the WMO, the World Meteorological Organization Regional Center for North and Africa, Middle East and Europe that is providing daily dust products. And these daily dust products include three days forecast of dust predictions. Then the stakeholders are related with the operation with aviation and people that is working in the airports can get this information and try to mitigate the impacts of a potential extreme event related with dust, for example. And this is one of the examples. Again, the February 2020 event was well predicted by the models. And this information at the moment is not really used for their poor operations because they are not aware about this kind of information. And this is one of the things that we are trying to push also inside this Dasklin project, but also in this WMO framework. And with this also, this is another big example that was this last year also, the famous Godzilla. It was a very exceptional event that was crossing the Atlantic from Africa to the Barbados to the Caribbean. And the models were able to predict these kinds of events. Then here I want to raise the point that the information is there and we are getting access to the users that are interested in this kind of information. Then if you have interest, just send me an email and I will find you where you can get all this data. Thanks a lot. And... Thank you. And thank you to all of our three speakers for their fantastic talks. I'd like to open up the floor now for questions. And if you'd either like to drop the letter Q in the chat box and we'll come to you and you can unmute yourself or you can ask the question in full in the chat and I can read it out. So please ask any questions. Okay, one in from Sarah Derwin. Who says, this is for Dr. Jermont. What does this Sahara dust mean for water supplies from mountain systems? For example, doesn't earlier melt mean more water escapes the system? She says she lives in the US and much of the water in the West in the US comes from winter snowpack. Thanks for the question. So when the snow is melting earlier, it means that in mountain regions, the water availability peak is earlier also in the season. So it means that the water is available earlier in the season and not necessarily at the right moment for crop, agriculture or any other usage. As for the US and the Western US, I think there's an excellent paper from Tom Pager about that, which is called, I think the Rising Lime of Colorado. I can give you the reference if you need. Thank you. Any more questions? Any more questions? I think there's one that's come in but it might be from someone who's anonymous. So maybe you could just unmute yourself. I can't see who it's come in from actually. Was that Sarah again? Actually, it's me again, yeah. Sorry, no, that's okay. And I, sorry, I can probably speak faster than I can type. So this is a question for Dr. Vostas about solar panels. I was just wondering if there are mechanical, specific mechanical risks to solar panels from dust and sand that you could talk about a little bit. I understand the dust can cover the solar panels but I'm wondering about the mechanics of solar panels. Thank you. Thanks Sarah. So yes, definitely. The same way that Sarah, my colleague Sarah Bassard showed those magnificent effects of dust on the turbine surfaces. The more complicated the solar panel mechanisms become in those dusty regions, the more of those mechanical effects you will see. So being very plain, simply breaking down the mechanisms that make the solar panels move and follow the optimum sun angle. But even more, if you kind of try to relax a little bit the definition of mechanical and bring a bit of chemistry inside, it's not just the dust particles that drop on the solar panel and will block the sun from doing its job with the panel, but also they can mix with some chemical reactions and start corroding or eroding or disrupting the surface of the panel. So you have so many multiple channels, purely mechanical, chemical and so many other combinations of them that yes, it can become rather complicated. I hope that answers the question. It did, thank you. Thank you. So we have another one in, this is from Nicholas who says, and it's for Dr. Dumont and possibly others. Do you see an increase in Sahara dust reaching Europe and the Alps in recent years? I think maybe Sahara can also answer that more exhaustively, more largely than me, but from my knowledge, so it's been proven that over Central Europe and Caucasus there have been a recent increase in the frequency of Saharan dust even there. As for the French Alps in the reanalysis we are using, so Aladin reanalysis, there is no trends in deposition over the Alps and the Pyrenees, so it's neither negative nor positive, it's just not significant. And we're suspecting that there is nothing because the intranural viability of the deposition is so high that 40 years might not be sufficient to get a robust trend. Maybe Sahara, you have more information. As you said, there is no clear trend at the moment related with the intensity and transport to Europe, but it's true that this year and the past year was having a very exceptional event. And the one in February 2021 that you showed that was arriving to the Alps was quite exceptional and very social because all the people was looking at the snow and take this reddish color, then it was super popular, but also last year in 2020 there were these two exceptional events that was affecting Canary Islands and Atlantic and we'll see in the next years, but it is not clear trend, let's say. It's not really something that we can ensure if there is more dust in the, or more number of events. This is something ongoing research and maybe in next years we will see. Thank you both, and there's actually a question that's come in that's related to that, that you might want to pick up on a bit more or perhaps not, and it says, according to our observations, the intensity and frequency of winter time, Saharan dust events in central Europe is increasing. Is it also true for French Alpine regions? I think we already answered that question, but I agree with the fact that there are proof of the increase in the total Europe, but not over as the options appear in it so far, but it's ongoing as Sarah said. Perhaps I can chip in a little bit on this last question, because it raises a rather important and not so frequently highlighted aspect because it's not just the intensity that's important for the way society copes with or is affected or is prepared, but it's also exactly the frequency. So it's the temporal patterns that you're used to concerning a certain phenomenon. So sometimes this becomes a little bit or even more as important as the intensity because it has to do with the way a particular sector or human activity is prepared. And that has to do a lot also with the temporal patterns, not just the amount that is coming. So that was a really nice question here and it's important for adaptation to those changes that might be coming. Thank you for picking that up as well. So any more questions for our team? Okay, so one from Sarah to everyone. What are some of these adaptations? If you know the problem and you understand the reasons, it's possible to do some mitigation strategies. This is clear for desertification in some areas of Middle East or the agricultural part of the Sahel. If you see that the intensive agricultural activities is drying the soil, this is risky because this means that the extension of the deserts can be higher. Then to understand where are the sources and what are the associated reasons of these sources is important. And related with the fact of the frequency that Athanasius pointed, some of the issues that we are raising now when we are discussing about the intensity and the frequency is the new sources that the climate change can have associated. And this is really challenging because we are not really sure about the extension of the desertification problem. And when you are asking us how will be the future, we have to put it on the playground, also the anthropogenic contribution or contribution to the extension of the desert, for example. Then this is ongoing research and there is a lot of discussions and scientific assessments. If you have information in advance, always it's possible to be adapted. And when you have information that is giving you an idea about how it's going in each part of the domain, this is also very useful for everyone. Depending on the sector, you have to adapt the information. Like aviation, we are using specific variables for tourism as my point. The melting of the snow due to the presence of dust can accelerate the melt of the snow cover. This is really bad for the ski tourism, for example. Then this is something that now starts to be very like on the frame front of the discussions, how we can use all the information that we are producing in the research communities or more user-oriented activities. And adaptation is part of these discussions. Yeah, clearly, yeah. And perhaps to pick it up from Sarah, for example, for solar energy because it is so frequency dependent, the amount of electricity you can produce or you should produce and the prices change. So knowing this frequency information can also perhaps lead you to adaptation or adaptive responses about how often you should clean your solar panels because the cleaning has its own cost and you should sort of like optimize that cleaning and the way you clean what method you use according to the way the dust cycle affects together with other variables, the way solar panels produce hour-to-hour or day-to-day electricity and the price. So this can become very technical, sort of speak management adaptations. And for airlines like Sarah was showing, well, perhaps to reduce costs, to increase safety, you can modify or you can at least take into account the routes you are taking from point A to point B and you can overlay them with the amount of exposure you are having for your aircraft and engine and then you can modify a bit either your scheduling or your maintenance. It can even go down to modifying your insurance agreements with maintenance companies, engine manufacturers. So it goes as Sarah said, really technical and it's very sector specific and so adaptation basically means opportunities. You try to avoid the risks by trying to be opportunistic and try to change what you're doing and what you plan to do according to the new information. That's what we're talking about. Thank you. I don't know if you wanted to add anything there, Marie or is that fine? No, I think it's fine. I was also just thinking about in relationship to the question about water availability. So if there is, for example, more dust event and the snow is melting faster, it's also impacting the production of air power. And as Sarah said, when knowing in advance and taking that into account into hydrological model or snow model, then you can predict how much water you put into them or not for the production of electricity, for example. Thank you. Yeah, and Sarah says, great. Thank you. Any more questions for our panelists? Okay, well, if there's no more, it just remains to say thank you to our panelists for taking time out today for presenting and taking your questions. Of course, if you've got any more questions, follow up queries, then you can reach out to each of our panelists at their email addresses. I'm sure they'd be happy to talk to you in more detail. So...