 Very important for you to think, particularly for your country, these walls, these obstacles, like Dorothee said, that prevent you from reducing, let's say, the risk that relates to these air pollution exposures in your country, like the example we did yesterday. We want to go from 15 micrograms of cubic meter of PM2.5 to 10, which is like the WSO safe limit for PM2.5. So you scientists, you generate data, or not, or partial data. So how can you actually convince politicians and stakeholders to reduce these exposures in order to provide better air and therefore better health to your fellow citizens in your own country? So what stops you from delivering that? What stops you from preventing you, as scientists, to convey the important scientific evidence to policymakers? So this is what you have to think about. So with no further ado, let me welcome to the podium Dr. Olivier Sainel, who will do some very important case studies and examples that relate to calculating social costs for various health outcomes due to exposures to air pollution. Olivier? Thank you. Hello, everybody. I have two hours, even if you are a little bit late. It's okay. For the lunch, 55 minutes. So first, I've put on the slides more certainly than I will be able to present, but as you can download the slides, if you're interested in a specific point, I did not have time to develop it. You will, by yourself, have a look to it. Then my presentation will be in three parts. The first one consists in a case study related to health effects and monetization of health effects of air pollution, related more or less with the yesterday's presentations all along the day on the health effect of air pollution. And then I'm going to move to the second part, which will be on the economic assessment of climate change, so a more broad perspective with different issues at stake. And finally, a second case study related on the impact of climate change on Camargue, which is part of South of France, where we have a lot of problem with the flood and the effects of climate change are very, very pregnant, even currently. So, and last point, because it is difficult to organize a case study with you working on a computer on the economic topic, because none of you are economists. However, what I've tried to do is to ask you questions during my presentation. I will stop, ask a question, you will think by yourself and give the answer. I note them and then I present the answers. And I will do that five times during the presentation. So the first case study is going to be on the hidden economic burden of air pollution related morbidity. It's in fact a work we have done with three epidemiologist colleagues, Laura Perez, Nicole Nino-Kunzli from University of Basel in Switzerland, and Sylvia Medina from Santé Public France in France and myself. It has been published in December 2016 in the European Journal of Economics. And our motivations were the fact that we observe and we know, and you know now after all the presentation during these first days of this workshop, that the short-term effects of air pollution have less impact in terms of effects and economic effect than the long-term effects. But at the same time, it's more difficult to get data from chronic diseases. Also, although these chronic diseases are the likely contributors to the long-term mortality and the burden of the mortality in general. So up to now, it's very rare that the chronic morbidity has been assessed in economic studies except chronic bronchitis, which is a little bit well known. And for the five or ten years, some studies have been published showing that air pollution can contribute to the onset or the development of chronic pathologies. That is, someone is going to be asthmatic or is going to have a cardiovascular disease because of the exposition during the early stage of life for asthma or during the longer life exposure. And this is going to really onset this disease. So the perspective is a little bit different from when we study acute effects for which we have only exacerbation of a disease. Here, the whole disease is associated to the exposure or to air pollution. So there is evidence of earth effects due to living in proximity to busy road that is growing. And we can accept that the near-road traffic-related pollution may capture something different from the background pollution. What's the network measure as background PM or urban PM or depends where the captors are located? It is one piece of information, but the other one is the fact that you live close to a very busy road. So we can see here how the pollution NO2 PM 2.5 and ultra fine particulate matter here decrease when you move away from a busy road. When you are one kilometer away from a busy road, here you have about 10% of the ultra fine particulate matter. And when you are very close to it, you have 100%. And it depends also on the winds. If you are south wind or if you have, yes, south wind or wind, there is a little difference. But we can see this pattern of decrease for these three pollutants, for instance, depending on where you are from a busy road. Second piece of information, we have publications that show that traffic-related air pollution have health effects. So regularly the publication on this topic and we have also studies that show, for instance, for asthma risk in children, you can see that depending on your distance from a busy road, the relative risk of having asthma in children decreases with a significant relative risk when you are between 0 and 100 meters, meters from the busy road, and then non-significant, completely different from 1, that is no excess risk when you are far better than 100 meters. So the objectives of this case study were twofold. First, a methodological contribution. And this is what I'm going to present now, a step-by-step economic assessment of air pollution-related morbidity. And also, once this is going to be done, an application to estimate the health impacts and the economic impacts of air pollution with the standard measure and the one we proposed, the comprehensive health impact assessment for 10 European cities of the African project. Once again, it is focused on Europe because it's easier for us to get the data and there are more data in European countries than elsewhere, so here it's in Europe, but the methodology is valid obviously for every country. So the outline of my talk is going to present the methodology first, then the application, and some concluding remarks. So the methodology. What we propose is what we refer to as a comprehensive air pollution health impact assessment. We start from the idea that the population is exposed to different factors that affect health. Some of them are related to exposure to air pollution, long-term exposure to air pollution, and there are other factors. Then this population is going to develop chronic diseases that are onset by near-road traffic pollution, asthma or the cardiovascular disease, or that are not at all due to near-road traffic pollution, so block A and block B. Then what we are doing when we compute, we do a standard health impact assessment, is to compute the excess herbations that are due to background pollution, not accounting for the fact that they occurred in a population that developed this chronic disease due to exposure to traffic blood pollution or not. So we compute the blue part, A prime and B prime, and this is what we do with the time series analysis, for instance. But what we are saying is two things. First, if we can link exposure to near-road traffic pollution to the onset of chronic disease, we have also to take into account the whole cost of this chronic disease over the life, because without this near-road traffic pollution, there would be no chronic disease, so no exacerbation, whatever the cost. And second, the idea that even if the exacerbation of these chronic diseases is not due to background pollution, if it occurs in a population that developed chronic disease due to the exposure on near-road traffic pollution, we must also take into account these exacerbations that are not due to background pollution. Because if you are asthmatic due to the fact that when you were a child, you lived close to a very polluted street, then all the exacerbation of the asthma attacks you will have during your whole life will disappear if you were not asthmatic. You see the point? And so what we are going to do is not only to assess the blue block, but also the red, blue and green blocks, and this is a comprehensive health impact assessment. The prevalence of the chronic disease plus the exacerbation in blue and the part in green of the exacerbation occurring not due to background pollution. So I'm going to move to the way we proceed, and this is the first question. According to your own background and your knowledge and what you think, which type of data do we need to develop a metric of traffic exposure? I know you have some lectures the day before, the days before even. So according to you, if you have to do such a job, what would be the type of data you should look for to be able to to do this computation? So the first step of the analysis. You can use a microphone. Thanks. How would you? I think that we need a number of vehicles. Yes. Exposed. The number of population exposed. Near to the traffic. The size of the population exposed. That is okay. The maybe meteorological condition. That's all I think. Okay. Yes. You should have the distance as you show from the roads, from the main roads, and you should have data or mobilization of the concentration of particles from the road moving, I mean, to have the exposure level. Then the metric of the exposure level, I think it's a matter of debate, if mass or number of particles. But this is, I don't know if you consider this in your study. It will also be interesting to look at maybe some hot spots like traffic lights. Yeah. Thank you. Maybe also the list of the different pollutants emitted by traffic activity. Okay. And the concentration. I think the very thing is how much the amount of the emission come out from the vehicles. Very interesting. I also think the type of vehicles will be the type of low risk. Okay. Okay. So we have more or less. The topography of the place in case there is a mountain that is blocking or something. Okay. And the type of pollutants emitted like if it is PM or NO2 or something else. Maybe the type of fuel that the vehicles run on, either it's diesel or petrol or I think mass concentration and must be the number concentration for the ultra fine particle matter because ultra fine particle matter causes more health, more adverse health effects and even cancer causing. So if you understand the number concentration and mass concentration, we can decide the metric for the traffic exposure. And by that way, you can measure the risk assessment for a particular chemical species. Without that, you cannot say this is the high or low air pollution is going on here. I think so. Okay. Okay. Thank you. We should, I think we should also know that the type of the type of the kind of people living along the street. Yes, it has been said somewhere in a different way, but okay. And the last point just behind you. And I think a wind speed and wind direction can be also a good point. Wind speed and wind direction. Wind direction. It has been said also. Okay. In fact, I don't have the question. So someone said there are some passive and active devices to measure the pollutant concentration and to say we can check a worldly traffic pattern, climate, sun exposure, wind speed, season. Okay. So what you proposed, you had the answers. That's how, yeah. What you proposed would be in an ideal world because knowing for a given city over a year or several years, the wind speed, the type of traffic, the type of vehicles, the meteorological conditions would be nice, but it's too much work. So what has been done is to use population distribution by age and census or building. You mentioned it. Land use map and traffic flow maps or road classification maps because there are two ways to take into account the link between the proximity to roads. To use analysis that have already assessed the relative risk with respect to the distance to the busy roads. And it is a difficult task, but it is an easier way to proceed. And the second thing, the second way to proceed is what emerged from your answer, that is to enter in more detail in what circulate, which type of vehicles circulate on the roads, which are the configuration of the road to traffic lights and so on. But it would be too difficult and too long task to do this. So how we proceed is that we use geographical information system to compute the distance of each grid point of the city with an associated population, I will show you in the next slide, with the nearest road classified as major road, that is a road on which more than 10,000 vehicles per day are driving on this road. And so we start from a map here of each of the 10 cities. We remove all the public buildings and we keep only the buildings where people live. And we spread the population of each of these, the census track was as precise as possible, depending on the cities. And we spread all this population in each of the buildings. So that after that we compute the distance here of each of these block of people spread in, depending on the size of the building, to the distance, the busy road, the more close to this part of the building. It was a zoom of this part. And then we get for each of the city a distribution of the population, depending on the proximity to the closest major road. So this was for the epidemiologic part. For the economic assessment, what we need with respect to the standard health impact assessment is to value the box A, that is the prevalence or the onset of chronic disease. So we have to get a measure of the whole cost of asthma or the cardiovascular disease we have chosen. And then we have also to take into account the fact that we cannot count the full exacerbation cost for the patient we developed this exacerbation and the chronic disease onset due to exposure to air pollution because the full cost of prevalence already include a small part or a share of the exacerbation cost. If you count how much costs asthma per year being asthmatic per year, there is a part which is due to the treatment. There is a part that which is due to the fact that you lost quality of life, but there is a part that is due to the exacerbation of asthma that makes you go to hospital. So this is exacerbation cost. This part is already included in the prevalence cost. So we have to compute a partial exacerbation cost for those cases of exacerbation that occur in the population that develop the chronic disease due to exposure to a near road traffic pollution. Maybe it's going to be clear with the application. So we need for the standard approach, the health impact assessment, standard health impact assessment approach, we only need the full exacerbation cost and we apply it to the number of exacerbation depending on whether or not it is due to near road traffic pollution. For the comprehensive health impact assessment method we need also this full exacerbation cost, but we need in addition a partial exacerbation cost to be applied to the exacerbation that occur in the chronic disease that occur in the population that are due to near road traffic pollution and in addition we need the cost of chronic disease onset due to near road traffic pollution the red square. So now regarding the application and I will go step by step so that it's going to be maybe clear. It has been done within the AFECOM project during three years. There were 60 scientists that work in 25 cities in 12 countries of Europe. These were the 25 cities with a blue square. You can see that there are a few in Spain, in France, in Italy, in Slovenia, in Romania, Athens, Budapest, Vienna, Stockholm, Brussels, Liverpool here and also Dublin. But this work has been done for only 10 cities, the 10 cities with the blue square because it's a very huge task to proceed to the computation I showed before that is to go to the map of the city, remove the building and so on and so on. So it has been done for the 10 cities here. The second question. Now to implement this application, which type of data do we need in addition to the one we need to measure the proximity to the V0 of the population. So some are obvious. To really compute this cost, imagine that we already have the computation of the number of people, the number of persons exposed to... What we get is a distribution of people depending on the proximity to a major V0. Now we need some different components to be able to compute the cost starting from the epidemiology. Probably the cost of the healthcare in each of these cities and the accessibility and so on and how much it is developed and so on. I think it's almost the same. I wanted to say the hospital admission and the medicine prescription by a medical doctor. The number of times I mean those who are around that road, I mean they go to the hospital for I mean respiratory or cardiovascular disease. Also we need to know which diseases are related to air pollution and what is the percentage or the contribution of air pollution in burden of these diseases. So to be able to calculate from this the cost and saved lives also, the share of this. Yeah my point was similar here. It's if you have specific relative risk for each city or if you have to use WHO mean relative risk or something else for Europe. So we need another suggestion here for epidemiological study. I think first we need some parameters you can derive from the U.S.C.P.A. or WHO. Just like for if you need to calculate the risk for adult and children for child. First you should note the some specific parameter like body weight of adult and children and air inhalation rate. If you are focusing on the inhalation rate how much you are inhaling the air from outside inside our body. So inhalation rate is very important in of course in cubic meter per day or body weight in kg. And similarly you should know the what is the for example suppose you are going to calculate the cancer. So for that you should know at least you should derive from some specific sources the cancer's low factor of a particular chemical species which are already present on to the particulate matter or even ultra fine particulate matter. So if you are going to study for the epidemiological point of views or risk analysis we should have we should must have the parameters for adult and children. It is good for specific for any cities for epidemiological study. I think so. Okay that would be an ideal survey where you are proposing because. I think number of mortality in these cities information of air pollutants and the number of people exposure for pollutants and we need to update the index of limitation of the pollutants in these densities. Okay for the morbidity part is okay. The first one mortality we are dealing with morbidity here so but the other one okay. So we have more or less all the information that is the population the measure of the concentration of the background level of air pollution. We already have the exposure of the population to the due to the proximity to to near road. We have to choose a relative risk. As you said we cannot proceed and go in detail to the hospital and the number of cases observed in hospital. It's a woodwork by itself doing that. It would be better but it's a woodwork. How we proceed is to work statistically and apply relative risk of developing this chronic disease and also relative risk associated to the proximity of living close to this busy road. So here are what we get. First I explained the two scenarios. It's a global burden approach. We study the two steady states. The move from the current situation in each of the densities to the situation in which nobody lives near to major cities so nobody developed chronic disease due to living close to major roads and the background pollution is the one associated to the air quality guideline from Wu for PM10 and NO2 that is respect the annual mean of 20 microgram per cubic meter. So this is the background pollution is used to compute the exacerbation case and the proximity to road exposure is used to compute the share of the onset of disease due to this exposure. So we have the densities here the population as you said the background annual pollution in the second and third columns and then the fraction of the population which is exposed to traffic pollution within 75 150 meters depending on the cities you can see that there are major differences. So we have to choose two chronic outcome. It's going to be asthma prevalence for children and coronary earth disease for people over 65 because this way at the time of the study the two chronic diseases for which we can get the more there are scientific literature what the the more robust in associating these two chronic diseases onset with the exposure to near-road traffic pollution. We choose two acute outcome that is the exacerbation and it's easy for asthma. It is hospitalization for asthma for children between 0 and 17 observed in each of the 10 cities and the same thing for acute myocardial infarction which is an exacerbation of coronary earth disease and then you have here in the table the relative risk or the for or related to the health outcomes for the prevalence and for the exacerbation and you apply this we are going to apply this to the population to get the number of cases associated and then this number of cases are going to be valued through the economic part. For this part we also did a literature review looking for the morbidity costs related to asthma so you have several studies and you have the fat black line here which represents which represents here the the average the mean here you have the distribution of the values of substance in literature we did that for asthma and for the coronary earth disease so that finally we get the economic value and this is what we need to compute the average cost per exacerbation by the cost of illness approach for each of the countries involved we have the average length of day at hospital for an hospitalization for asthma or for acute myocardial infarction we have the average cost per day at this hospital the average work loss due to this to chronic disease they are quite low because the the population is over 65 or below 17 so they are not a large share of the population who is working at these ages about eight percent so this is why the average cost is low then you compute the direct average hospital cost by multiplying the length of the state hospital times the cost per day for each of the country and for the two CD onset here here you did we did the same thing for the average cost of work loss and finally we get here in the last column the average hospital cost so this is a summary of the unit economic values we have chosen here and the way we account for the fact that a share 50 percent of the average cost of asthma is due to hospitalization and 21 times about 21 percent of the annual cost of having a health disease is due to hospital costs so we remove this from the fully sufficient cost to account for the fact that these costs are already taken into account in the annual average prevalence cost of asthma and coronary health disease and we get this result I'm but I it's not readable but I sum up this result I just explain you have here all the boxes the white the blue green and red boxes the number of cases the economic value for the standard health impact assessment and for the comprehensive health impact assessment and I present to you a summary of the results when we compute on these ten cities in these ten cities the standard approach we obtain an average cost of half a million euro when we take into account the exacerbation costs that are not due to air pollution that is the green block we obtain an additional 8.3 million euro when we compute the prevalence cost you see that the prevalence cost is going to be the the larger part of of the cost because it's going to last for a long time and it's also more important in terms of costs so we add a 362 additional million so that the approach we apply to these ten cities get as a result that the comprehensive valuation is about 370 million to be compared to the half million obtained with the standard approach so as a conclusion we can say that uh first from an epidemiologic perspective the pollutants along busy roads could be responsible for large but preventable burden of chronic disease we found considerable larger burden of air pollution than when the standard health impact assessment and the best preventive action is to avoid the exacerbation by avoiding the disease altogether if you remove the fact that that people are going to develop asthma due to exposure in infant when they were young to to air pollution you remove the whole life cost of asthma for these people and this approach can be applied to other diseases associated to air pollution like chronic obstructive pulmonary and urinary disease or lung cancer for instance or even other other type of benefits when the this is the same substance that causes the chronic disease and causes the exacerbation as soon as it is the case in agriculture energy health transport waste water and so on if the same substance causes the chronic disease and the exacerbation then you can apply this approach okay this is over for this part we can switch to the other the staff technical staff please Alessandro we have to switch I have a question Olivier um how would you deal with the population data do you have the distribution by age we have the distribution by age or maybe not no I think there's only I don't remember if I we have by age below 17 above 65 yes and the whole population yes any other question when we switch shift to the other presentation no okay okay then let's move to the second part which is the economic assessment of climate change I slightly change the title because economic cost was too broad and here I focus on the climate change if I have to sum up the big challenge we face as as human being or economist face when trying to to tackle climate change it would be determine how much society is willing to give up today to reduce the consequences of climate change tomorrow it could be through mitigation policies to reduce the emission of greenhouse gays or adaptation policies because we know that there will be an increase in temperature and these adaptation policies allow us to reduce the consequences of climate change and the major differences between this challenge and what we have to tackle with local air pollutants are not on the impacts on health which are almost similar but in deal with the impacts other than health with non-market dimension there are more uncertainty because we also work with a more distant time horizon so with local air pollutants most of the effects are either short term a few days or a long term that is 30 40 40 years with climate change we are speaking of century or millennia if we are ambitious and for the economists the uncertainty is very huge and the impact of discounting is going to be one of the major uh uh trap we have to to avoid so the sketch of my presentation will be to have another view of the impacts involved then to focus on market and non-market values to focus on the economy just give a few results regarding the economic assessment of the costs and benefits of climate change focus on the influence of time because there are three components of time that are going to be involved in the valuation of the economic impacts of climate change and finally have the second case study on the climate change in Camarque so I think you have similar things but because I add the the economic component I will sketch the the picture with you we have air pollution that is going to first induce climate change with effects on uh oceans acidification reduction of marine resources with which means loss in yields for for the marine resources on the other side on the earth we have on the ground we have uh sea level rise extreme rain fails and extreme temperature which induce floods uh drought forest fires heat waves and these two have effects on buildings the violet blocks are the blocks we are interested in as economists for which we are looking for prices of value we have to value these impacts this is all the violet blocks that should be valued the seed these two uh blocks uh orange blocks are going to also have impact on the loss of biodiversity the deterioration of ecosystems and increase in pace of various types and these blocks is going to also decrease the yields in food and in forest resources the food the flood this block is going to have health impacts directly physical or mental health are going to be involved because if you die in a forest fire or due to a heat wave or because you are flood uh so or if you are ill or injured due to this uh type of impacts then you have uh health effects here you will have effects regarding malnutrition or infectious disease these are labeled that uh indirect health effects and we also have this loss in the yields induce uh less food the forest fires flood and so on induce that the land where you live no more uh possible to live in so that you will have climate refugees conflicts for the resources which mean that we have what I labeled related effects due to the population displacement and the disease and protection from one area to the other because population are trying to survive and go to other places this is for climate change but air pollution has also effect locally which imply damages to building too you have to to to clean the buildings uh regularly there are also direct health effects we we have studied them uh yesterday we have also a loss of biodiversity deterioration of ecosystems increase in pace so that the whole picture is this one and we have also as uh Augustin uh told us this morning effects in the both directions between climate change and local air pollution so that we have in common most of the uh violet blocks should be valued and are common with climate change and uh local air pollution these are these blocks we should value as I said yesterday and as we will see in a minute the economic approach is anthropocentric that is something as a value because we need it in a way it affects our well-being directly it may be the fact that I know that this type of birds is preserved in Amazonia as a value for me it may be not a direct choose but it has a value because you think as human you are on earth and you think it has a value because if there were uh no human beings on earth we would not be trying to assess the impact of climate change there will be less climate change by the way so this change in well-being have indirect effect on the environment variables and also direct health effects and so we can allocate these different blocks to these two uh type of effects we have here the indirect effects on the environment and the health effects that can be uh considered with the three uh distinctions I've made but also they cover in fact direct cost hospitalization that is morbidity and mortality and indirect cost and uh here we can see that clearly that all the parts dealing with loss of biodiversity deterioration of ecosystems and increase in pets are related to non-market variation there are no direct markets that allow us to have a price for this for the damages to buildings and the loss of yields for us resources or food you have a market market for cleanup cleaning up buildings uh the food market uh the price for wet rice wine whatever you want timber as a as a market as a market too so you can observe price on the market for the health effects we have seen yesterday that uh if I uh I do this uh little uh reallocation we have the market values mostly the morbidity effects and the loss of production you have wage market job market and you have tariffs for hospital cost and you have also the non-market dimension that is the main one being the value of premature death and the psychological impact of living in a polluted place or or being flooded if you survive to a flood the fact that you have been flooded and you may have uh feel fear and it may affect you you may be in post-traumatic stress so there are also uh psychological effects so what the economist is looking for dealing with climate change or uh local air pollutant is to try a way to value all this dimension and the additional uh thing to be taken into account in the climate change uh approach is that we are dealing with very distant horizon so now if we consider market and non-market values I will present what we mean by value as an economist so as I said it is anthropocentric it expresses the degree to which a good or service satisfies individual preferences and it is based on the fact that you are willing to trade off something against a good it may be money and you prefer spending money for a specific good than another though it is a trade-off between these two use of money that explain that you attribute a value to something or it may be time if you sacrifice some time to get something it is because this thing has a value for you but there's for ecosystem biodiversity or think like that of the value of life we have no markets so we have the two approach we have uh uh seen yesterday there's a revealed preference under stated preference approaches that can be used and uh before presenting them and asking you another question I will decompose I will split the the economic value in different components uh what has a value for you is it has a value why something has a value for you it has a value because you can use it you can use it by with consumption it is a fisheries timber agriculture or without consumption if you walk in the forest or if you have some educational activities related to nature for instance you do not consume per se this good but you have a direct use of this good you have also an indirect use value that is provided by the ecosystem the carbon sequestration services the some coastal ecosystems also provide ecosystem services all the self-perifying properties of a wetland for instance there are also potential use value that are unrelated to a current or future use that is an option value that is in the future I may have some personal direct or indirect use of a good but I do not know currently which it is going to be and you have among the potential use values the informational value which is related to the fact that when you decide something what to do to improve the the future situation you take decision if this decision is irreversible the economists are giving a value to the fact that you delay an irreversible decision waiting for future information that is we sometimes we we do not know currently the scientific are not enough reliable in the in the conclusion so we are going to wait a few years before deciding but the fact that you wait for a few years as an economic values which is called the information informational value you wait until you estimate you get enough information to take a decision but the fact that you you miss some possibilities of action during the time you wait as an economic value and finally we have the non-use value or passive value among which the existence value the simple fact that you know that a certain good on service exists somewhere like the bird in amazonia has a value for you even if nobody use it or nobody enjoy it you and nobody sees this bird in amazonia it may have a value the biggest value corresponds to the fact that you may preserve some goods for the future generations and the artistic value the fact that currently today you do not use a good but you know that someone else can use it today benefit from the good of the service and it has a value for you all this aspect constitutes the total economic value that is all what is embedded in the concept of economic value the use values the non-use value and we you can see here that the market components is only a small share of the all the value you can get that is here a share of the direct interaction Zeus with consumption correspond to a market component but all the order and non-market component you have no value for altruism no value for instance value for because variance one you can you must find other ways than the market to get an assessment of the value for these components i'm going to skip the reason why it is important to value and yes maybe just study why we should account for the total economic value because cost-benefit analysis implies both market and non-market components and the the standard procedure to estimate a cost-benefit analysis is to compute the benefits to compute the cost maybe start by the cost and the benefits and finally compare the cost and benefits for the benefits you should identify all the things that are damaged plants animals human health aesthetics once you have done that you determine determine you estimate you choose a relationship between every possible action and every damage level that is you use a relative risk for us for instance then you place monetary value on each of the damage then you submit and you get the benefits for the cost you have to assess the cost of an action or cost of a policy once you have done that you should compare the cost and benefits by aggregating them at every date in the future and then discount the future cost and benefits that is put in current value today's value the flow of cost and benefits in the future that is using what is called a discount rate the kind of inflation rate i will detail that later on and finally account for uncertainty this is the whole picture of what we should do in the cost benefit analysis and what is going to be done here is to check how to get a variation of the damage and then how to account for discounting the future and the uncertainties so as i said there are three ways the market price approach we have seen that yesterday but as i said for okay i already said that okay this is our market work at equilibrium you have a quantity on the price on the market and then you can get a price to be applied to the market share of market component of a good or service but you can also use this market approach to value some environmental goods or services from the market cost that would be necessary should these goods or service disappear i give an example here and you will have to think about it it is a question the question is how can you use the direct market approach to value the loss of a wetland that is you have to do the question has two components first what is the value of a wetland and if the wetland disappear what would be the loss for human beings and then how to value this loss difficult question so you you came from different backgrounds so some are more familiar with what are the services provided by wetlands so what is a wetland useful for from a general perspective yes thank you it's a huge question basically wetland means a lot to us we can say ecologically it's the it is the kidney we say it's a ecological kidney it filters surface impurities and gives us clean underground water i know that drinking water we get it from underground ecological uh fit yeah good that's it there's a noise from the ecological food benefit benefit okay okay and secondly we use the wetlands in various manners for example we cultivate fish so it gives a huge value for us we have a food money as well and secondly in india water is very important for every religion every culture so we take what bath we use the water for many religious activities so the societal value is also very important in that case so disappearing wetlands means a lot because it also supports a biodiversity huge biodiversity food i mean birds fishes amphibians and many more so it's a lot huge loss wetland loss means a huge loss to economy ecology and society as well thank you so you said recreational activities more or less religious and okay and ecological benefits that this is two of the components there are at least two others that have a value for human beings people living close to these wetland areas yes that and losing wetlands may cause many damage to economic because of cultivation we lose cultivation around these wetlands and this can be economically a big damage for the surrounding people the people who live there moreover the ecosystem that he told ecosystem yes and the first one is you lose cultivation i mean farming farming okay okay agriculture it was already mentioned okay there are two or yes maybe there will be some people who lost his works and the culture maybe it should be emigrate so maybe the immigration of the people okay left there a related effect okay so the two other were self-perifying property we have another another utility for wetlands in Kolkata we have big wetlands and it is around society so the entire city liquid switch comes to that wetlands and on the other end of the wetlands we get a very fresh and pure water very clean water because that is cleans the impurities exactly it is self-perifying properties this one and the other one about a decrease in food flood probability so this these are the four main things we can associate to to wetland and then how could you value these four components so the increase in decrease in flood the so the dispersion of wetland is going to increase the flood probability to decrease recreational use to decrease biodiversity and to decrease self-perifying properties so well these are the four main components and how can we use direct method of valuation through markets through prices to assess what is the impact of this degradation or loss of wetland which is more or less non-market there are no market for wetland but there are these four components that may be valued through the market price approach because it is economic so I will summarize here so as we said there is an increase in flood risks and this can be valued by estimating what would be the health cost in case of flood and what would be the cost of the damages to building agriculture and commercial activities in case of flood then for the decrease in recreational use fishing and leisure religious activities there is a cost in the local economic activity restaurant hostel people visiting Iran so there is a loss and direct loss due to the loss of fishes for the decrease in biodiversity it's going to need the reintroduction of extirpated species to regain the quality of the damage ecosystem and so there is a cost of reintroduction of these species you pay people to put these species back to the environment initial environment and finally for the decrease in the self-perifying properties of the wetland you can compute what would be the cost of a new or a larger water treatment plants to replace the work that was done by the by the wetland so you can see that even for something which has no price per se the wetland you can find ways to estimate the value of this wetland by using the the market approach but these four components do not deal with the non-use dimension because if you benefit from an improvement in the decrease in the risk of flood or the local activities or the damage to building in case of flood or the introduction of species it's direct use people are going to benefit directly from this it's not in the future it's not altruistic it's not because value is not existence value so it's use value and market can only value direct use value not non-use value so to be able to estimate the non-use components we have to use the direct approach which is a stated preferences to ask people how much are you willing to pay to preserve this wetland by saying that they will not only consider the direct benefits they can get the four we have mentioned earlier but also the fact that they can preserve this wetland for their children for other people i'm willing to pay something for people living in another place of the country or in the world to preserve that this wetland and this cannot be assessed by the direct market approach so if you want to add to the direct use values we have assessed for the three components we have identified for wetland we should also use stated preferences to estimate the non-use value in conclusion the economic assessment of climate change will require the consideration of many impacts specific to different sectors of the economy some have a market price some do not have a market price and even those that have a market price we can also only capture for these components the use value and this assessment will only be a prerequisite and we'll need to incorporate the temporal dimension we will see that in a minute the link with other environmental effects and be compared to the cost of mitigation and adaptation policies so then i have something related to the economic assessment of climate change but i will be very quick in presenting in fact there are two ways we must split in two categories the economic violation the first one evaluates the effects of climate change by calculating the expected damages for two scenarios that differ in magnitude or consequences for instance the reference scenario business as usual if we do nothing we will have these consequences alternative scenario if we succeed reducing the increase in the temperature to two degrees then we will have also damages but less damages and it is a difference between these two damages that constitute the benefits from a policy of mitigation of climate change it is a difference between two costs that is going to be the benefits of a policy and on the other side you have the cost of the policies that is how much we have to pay how much you have to change our behavior and what are the consequences economic consequences of changing our behavior today to observe this reduction in the inclusive temperature or the reduction is the damages due to climate change so we have the benefits part difference between two scenario and the cost of the policies by themselves so if we consider the economic assessment of the damages avoided that that is the benefits according to ecd some effects may be positive for instance tourism so some places in the world are going to have more tourists the gross national product of all countries except canada and russia will be negatively affected by climate change because canada and russia will have gain in terms of agriculture and partly in napal it has been mentioned this morning because of the culture that in the north northern india there will be also small benefits but they are cancelled by all the cost and the other part of the country for india so it's only canada and russia the two countries for which the overall effect of climate change when assessed accounting for all the components may be positive africa and asia will be the continent that will bear the greatest economic losses that would be the greatest economic losses and more or less health and agricultural impacts account for more than 80 percent of the total impacts and tourism energy and extreme events and impact on coastal areas account for the remaining 20 percent so these are average values and they are based on a complex model that introduced climate assumptions agricultural assumption economic models and there are a lot of uncertainties so don't take them exactly as a accurate figure it's just a broad order of magnitude so what are the uh a few estimation it's very general this morning augustin collette gave for each scenario very precise estimation of the cost in terms of billion of dollars and so on it's just expressed in term of gross national product to have an order of magnitude of the impact so an increase in temperature of two degrees Celsius would result from 2050 in most studies by an impact estimated between one and three percent of the gross national product per year and up to five to six percent depending on the assumptions if the temperature increases by four degrees by the end of the century it could be up to 10 percent of the gross national product and this uncertainty one two three up to five are due to the the effects that are assessed we have seen in section one that there are many effects the variation method used who have seen in section two that we can take into account only market non-market and values use non-use components of of the of the value of good the choice of the discount rate we are going to to see it in the next section and whether or not extreme events are taken into account so here for instance we can see following the AD this model the impact on the GNP GNP you have GNP on the y-axis here here you have time and you see for different scenario let's start with this central scenario here the blue one you have the uncertainty here expressed depending on the assumption and an additional uncertainty with other assumption and you see that at the beginning of the period there are small very teeny differences in the valuation of the impact on GNP of the climate change but as long as time passes the uncertainty increases and at the end of the century you can see that the uncertainty is very large and here it is the central tendency if we take into account extreme events the grade notes and you have even if it is not represented on the on the figure even larger uncertainty here around this central tendency so you can see that even if it is more or less all economists agree that it is about one percent the the impact in 2050 in 2100 depending on the attention you can see that certainty is going to be very large now regarding the costs of the policies there are mitigation policies that are looking for reducing the emissions and then reducing the speed of the climate change they are discussed in the COP 21 for instance every COP or every country try to to to say what he is going to they are going to implement to to reduce the speed of climate change and they are also adaptation policies first let us start with the mitigation policies it has been estimated that policies that would allow a 25 percent reduction in equivalent CO2 emissions compared to 2015 have an estimated annual impact between one and three percent of the global GNP here again there are large disparities between countries due to the mix of energy the sources of emissions and the the way of life and with the most favorable assumption it has been criticized by other economists in the report directed by Stern sir Stern this cost might be negative that is there might be benefits because he takes one of the assumption one of the scenario took into account in the Stern report the co-benefits associated to the policy of the mitigation policies and the most favorable assumptions lead to positive effects of the policies themselves usually a policy has a cost and here in some teeny cases it may have a benefit so it's a win-win strategy the cost of the policy you implement our benefits and these policies will have a benefit so you have double benefits but it has been criticized due to the choices in particular the choice of the discount rate and then you have the assessment of adaptation policies because we know that we would not be able to to even keep the increase below two degrees so there will be consequences of climate change so it's a good thing to think now how to adapt the society to the consequences of climate change and these policies are less costly they are between 0.2 and 1% of the global GNP and we will see that economists are more confident in the effectiveness of adaptation policies than of mitigation policies so they are more prone to implement policies that would adapt the society to climate change than to implement policies that will mitigate climate change so one of the crucial components of this valuation are discounting discounting as I said is a way to compare intertemporary financial flows and the choice of the rate is crucial I will have figures that will make this very obvious for you and there there are the we observed a crucial change in the choice of this discount rate because until the until 2000 most of the report use a very high discount rate and by doing this if you discount the future very highly it means that the future has almost no value not by choice but by the choice of the discount rate you assess the flow of future benefits with the high discount rates it means that the future benefits have a low value today when you have to decide now what would be the you how much you are willing to pay to implement these policies because the flow of benefits in the future is reduced you will not be prone to implement ambitious policy and they were discouraged because the view was a short view at short term because the future have no no weight then Stern in particular proposed a very low for opponents discount rate of 1.4 percent that this discount rate gives a high significant weight to the future and then it advocates immediate and important measure to limit climate change then to compare the the cost and benefits of mitigation policies as I said economists are divided on the scale and the implementation agenda of greenhouse gas emission reduction policies and even if most advocate for prompt and important action they agree that costs remain lower than the consequences more or less but the order of magnitude is not very large if you compare it's about two or three percent in each case so if you add the uncertainty to these figures the cost-benefit analysis of the mitigation policies are not shared by the community of economists but for the when you compare the cost and benefits of adaptation policies here the conclusions are more concordant because the costs are about three to four times lower than those of the mitigation policies and because the benefits are half then you have costs that are four times lower and benefits are that are twice lower the balance is in favor of these adaptation policies oh I will skip that you will look by yourself why thank you just this figure is interesting because it is close to something that Augustin Collette this morning showed in order to limit the increase of temperature we have to reduce the emission of CO2 equivalent each year some studies have said that we need a reduction of 38 gigaton of CO2 to be able to reach if we start in 2010 we need to remove 338 gigaton of CO2 emission from now to 2030 the way we can remove this emission can be ranked correspond to policies and these policies can be ranked depending on what did the cost of the policies that is what is the cost of each ton of CO2 equivalent removed there are different policies on lighting of micro electronics car hybrid cars plug-in hybrid change in agriculture organic solar restoration and so on and so on and you can rank all these policies and compute what is the depending on the cost of the policy depending on how much it's going to remove CO2 from the atmosphere what is the cost of an abatement of one ton of CO2 and you can see here that all these policies below zero the cost is negative that means that for instance if you replace lighting and you switch from incandescent to lead in addition to the fact that you have less electricity to be used because and then you remove when electricity is produced by coal for instance you remove CO2 from the atmosphere you have additional benefits the paid price because they are lower consumption so that all the benefits up to here all this one ranked here are the ton of carbon removed is a benefit and not a cost and then if you rank them up to here you see that to reach the 38 gigaton CO2 equivalent per year the last policy to be implemented to which this would be changing gas plant and the cost of one ton of CO2 equivalent removed would be around 80 euros which is which is relatively low because for instance in the price of a carbon ton in sweden is currently about 100 euros for instance so there exist policies that are implemented and for which the cost of one ton of CO2 removed are higher than 100 euros so you can see that if we decide to implement all these policies starting by the most effective effective to this one we can succeed in removing this 38 gigaton CO2 starting now and before 230 and the cost will not be so so huge in conclusion since measures to limit climate change will probably be insufficient we need adaptation and limitation to reduce the damages due to climate change and this may offer some economic opportunities the co-benefits have been presented a minute ago and this will also reduce the scientific uncertainty because if we reduce the speed of the climate change will reduce the uncertainty but we must act very quickly because time is going on in every sense and then we have to take the decision very very quickly and finally we must pay attention to the ethical issues when you consider the global issue of climate change yesterday we were in the local air pollutant framework and we were reasoning within the country but here when we are we have a global approach we have to pay attention to the fact that if we use country specific values for the value of prevented fatality due to climate change then we have ethical issues when depending on where the death are avoided so we have to to be aware of that then regarding the influence of time I will focus on discounting so for economists discounting are composed by four components here the pure preference of the present the gross weight of the economy the relative aversion of temporal inequality and the precautionary effect you have the definition you will look by yourself on the pdf all these components are positive negative can be positive negative or or null and they are summed up so that more or less they rely on uh beliefs they rely on subjective values so that the the range of the discount rate discount rate that can be used is between 0.5 and 10 percent if someone choose 0.5 it's not going to be absolutely stupid if it's about 10 it's the same thing it's the extreme values but there are plausible values we can find in the literature but the more distant the temporal horizon is the heaviest are the consequences of discounting on the valuation of future monetary flows and I will show you this with the two values of the discount rates used by Stern 1.4 percent per year and up to the year 2000 around 10 percent to show you how much the issue is important here you have euros on the y-axis and years one century on the x-axis 100 today if you do not discount is worth 100 in each of the 100 following years 100 euros today is worth only 25 euros if you use the discount rate proposed by uh Stern that is 1.5 percent per year and 100 euros today is only a few cents if you use the discount rate of 10 percent per year so you can see from some that uh it is equal after 50 years to 100 when you do not discount to uh 50 euros if you discount at the rate of 1.4 and to 85 cents if you discount at 10 percent then imagine a flow of benefits that are 100 euro per year during one century if you do that without discounting is 100 times 100 is uh 10 000 so one a flow of 100 euros not discounted after one century you get 10 000 euro if you discount at the rate of wine at 1.4 per year you get less than 6 000 euros and if you discount by uh using the rate of 10 percent you get about 1000 euro you think that the effect of discounting the choice of the discount rate is one of the major uh assumption to be done and make the uh valuation differ uh even if it was the same assumption for the other uh choices done so which rate should we use here again there are no market for discount rate there are market for interest rate but not for discount rate because it includes other components than the growth of the of the economy so there have been a few years ago a survey which is called a delphi survey which means that you ask uh people that should have a little knowledge on this topic that is economist uh white man in 1998 asked 100 uh 1700 economist what they guess the imagine should be the the proper discount going to be used for projects with distant effects more than 30 years and you have the distribution here of the answers of this economist and more or less the the value that the median value is about two two thousand two percent per year so uh if you have to choose a discount rate the choice of around two percent per year would be the proper choice the second way time uh time enters the analysis is through a certainty because there are several uncertainties as economists we uh collect the certainties from the other disciplines uh agriculture epidemiology uh and uh specialist of marine resources and we add our own uncertainties so we have to account for all these bundles of uncertainties some are scientific related uh some are human related under evolution of the population of the habits of the population the economic condition the technology that would exist in 50s years to reduce the CO2 emission on the consequences of climate change some are methodological we improve the models we introduce uh different components of value we use different values for vpf and overall they accumulate for air pollution we have less uh uncertainty because as I said it's short shorter term effects and we already know most of the effects that exist on morbidity and mortality and the impact on crops are known and building are also known for climate change as you know there are much more uncertainties at each step of the uh analysis so that the confidence intervals around the values given by ipcc for instance show how important are the uncertainties in here you have time here you have the annual gg uh emission emission and you see that the envelope of the laws of the order scenarios here you see that uh in 2100 you may have a decrease between minus something and plus 200 uh gigaton of CO2 uh equivalent failure so depending on the scenario even within the this one this one this one and this one you have an uncertainty here that is mentioned with the bar the colored bar here and the the wool envelope is uh entails a huge uncertainty I will focus now on the concept of irreversibility which is linked to to time because for uh greenhouse gas we have huge and irreversibilities in terms of emission and the ecological irreversibilities due to the fact that CO2 disappear in a few centuries from the atmosphere in fact that even if you reduce today our emission there will need we will need time to stabilize the CO2 concentration several centuries to stabilize temperature increase and a few millennia to stabilize sea level because of the inertia of each of the systems and there are almost no ecological irreversibilities for local pollutants because there are no stock buildup or the the meteorological condition make things move very very quickly even if nothing else change we have large economic irreversibilities for the greenhouse gays and local pollutants because we have to implement policies that are ambitious and are going to change the practice and the habits of people and this will require time and uh involve uh sink cost so all this put together that is huge uncertainties and irreversibilities imply that the concept of flexibility of a policy when you are looking for an optimization is crucial because you have a rival of information the rival of information from the scientific perspective is important because there are scientific publications every day the IPCC produce a regularly report on the effects of climate change we do not know what would be the effectiveness of the implementation of a policy but after a few years we can see by ourselves whether or not the policy was effective we do not know what would be the next conclusion of the COP for instance what would be the announcement of the various countries uh related to the policies implemented to reduce emission and at the same time the irreversibility of the phenomena will not allow rapid policy change if you decide to change all the nuclear power plants in France by other way of production it will request decades to to obtain that it's not going to be very uh rapid so all these say that uh when you decide to choose to implement a policy at a given date for a given objective you must have in mind that it should be flexible enough to adapt to a new arrival of information you then have to end bend a new decision process what i've called earlier the informational value that is the component of the total economic value that is devoted to the fact that you are waiting for arrival of information and this has a value and a simple uh why i submit before showing you the graph the figure the choice you have as a public decision maker would be uh that you face a double edge constraint that is you should avoid acting too rapidly and too strongly which could have significant short term effects on the economy and the population but by the same time you should avoid acting too late and not be able to meet reasonable targets to limit climate change because of these irreversibility effects so you you have to to here for instance the figure i think it is more clear imagine that you decide here which policy to implement you do nothing is the reference in green here these are the emission in gigaton of equivalency or two if you decide here that the target is a 550 particle per meter per million in the in the atmosphere of co2 you choose the pink trajectory here and you get here you have all this emission if you say i'm going to decide which would be the target in 2020 only you start by being less more ambitious regarding the reduction of emission here to be able to reach each of the three targets in 2020 when you have to decide here and in 2020 if the arrival of information say okay in fact we should really limit the emission in order to uh 550 ppm at this horizon oh it's the wrong time reversal i took this picture from this this so i think that's a mistake in the date here so then you can relax a little bit the constraint to stay on this red line if at this time you see in fact there are a lot of extreme events we that were not planned here and we learned that it's worth that what we thought then we can change the trajectory to to try to limit the co2 concentration to 450 and in the opposite if we find that the arrival of information are in fact positive and the problem is less acute than we thought you can relax a little bit here to reach 650 ppm target so in conclusion we have to take into account time the economic approach of the effects of climate change because the horizon is very distant and this lead to more complex analysis because we have to choose a discount rate and the choice of a discount rate is crucial and there are more uncertainty about its economic valuation and in addition it has a subjective choice to be done because there are no market for this content as i said okay then i'm going to move to an application on climate change in camargue i have a don't don't it's okay so what what is camargue i will show maps but ah yes i will show maps this is south of france yes delta south of france so it's a regional park in addition about 100 kilometers square kilometer located in the ron delta 70 percent is less than one meter above sea level and 25 percent of this area is below sea level it suffered major storm the three last in 1982 1997 2003 and some major floods in 1840 you have the date and it has lost 330 hectares since 1945 gained by the sea according to the nazar who control and maps every year on continuously the surface of the earth it is a place in the world where the sea gain the more rapidly it's about four meters per year during the 50 last years so that is a place interesting to to see what would be the effect in other places in the world with the less rapid evolution we will see why it is particularly prone to climate change it has been classified biosphere reserved by unesco it is a place where we have wetland area dryland freshwater mediterranean sea agriculture industry tourism fauna and flora that are melt in this in this place as you see we are here this is france here it's camargue map of france with a zoom here camargue is here between montpellier and marseille and this is in the ron delta here here you have big lakes you see mediterranean sea is here here you have industries and here you are salt industries salt march if you have tourism almost everywhere and agriculture in this part and the rice so here this is the national park this is some pictures for the nature for the wildlife with white horses and flamengo pink flamengo here here you have cattle with bulls you have rice culture and you have industries with salt extracted from the the mediterranean sea and tourism here okay now why is camargue particularly exposed to climate change there are two reasons the three of them there are five reasons three of them are due to climate change and the two last one are due to the special configuration of of camargue first the sea level rise as i said it's causing a sea advance of about four meters per year for 50 years which leads to an increase in sea salt in the in the ground which hinders agriculture and degrades flora a degradation of the dam at sea protecting the coastline we can see here there is a big dam here from here so here there is a dam that protect all this area from flood entering from the mediterranean sea but sometimes when there is storm and low pressure lot of atmospheric pressure and high waves then it enters and it takes a month to go back to the the sea the salt water going inside the camargue in case of flood coming from the the sea requires a month to be completely removed so second reason there is an increase of rains and storm intensity with this going to fill the ponds or the lax within the camargue which are difficult to empty when the sea level is too high and cause floods of the run which increase the risk of breakage of dykes if there are too much water too much rain then in addition to filling the the lakes in the camargue it's going to increase the debit of the run which is a major river in france and then there can be flood coming from the run in addition to coming from the sea and there is also this is a paradox but higher rains and also an average loss in the flow of the run due to drought episode which leads to a rise of salt in the soil the technical term is salt wage and more more and more inland and a loss of freshwater resources coming from the run so the run did not bring enough freshwater to camargue to fight against the salt coming from the sea then there are two additional reasons that aggravate the the effect of climate change the first if the decrease in the alluvium carried by the run a division by four in the centuries or there are less mud less little stones less alluvium bringing by the run in the camargue and this is due to the domestication of the the run and changes in the agricultural practice in the run endurance and in addition there have been dykes along the the runs that do not allow the river to deposit the remaining alluvium they have been divided by four and in addition because of the dykes along the run they cannot enter the camargue and and bring some materials some alluvium in the camargue and finally the run delta is constituted constituted by of alluvial deposits and it sinks independently from other reasons it sinks by one millimeter per year if you have the sea level that rise and the ground that sinks in this combined to make camargue one of the places in the world with is the most exposed to climate change consequences then what are the the impacts of climate change we will see that there are three main impacts economic social and ecological there can be ranked depending on the their vulnerability to climate change in red you have the strong vulnerability to climate change in yellow you have the weak vulnerability or uncertain and they can also be ranked depending on their market components nature and non-market nature or all their mixed nature so first based on what I've said up to now based on the picture I've shown and what I've said before what according to you are the impacts of climate change in camargue five minutes one o'clock but it was you can skip the question but one okay but I will present the impact and I will ask on either second question so these are the impacts they are economic on agriculture tourism and industry there are social impacts on earth buildings and infrastructures and their ecological impacts on water resources and environments you can detail all the components here these components are vulnerable have different vulnerabilities to climate change the most vulnerable are the rice culture the beach and building the friction due to coastal erosion the marine submersion and here impact on water resources all the water resources and the salinization and erosion of the littoral zone and of fresh water wetland cycle are the most vulnerable to climate change then second question within these impacts which of them are market and which of them are non-market impacts so I put them on the screen what would be the the components that could be the impacts that could be assessed through a market so where do we have price more or less here more or less here okay for agriculture we have prices for all of that here the buildings and infrastructure can be evaluated by markets building okay water resources can be also as we say previously what you have to pay to I know this is another point no so no that no this okay and yes I I really have a question why the industry is affected because if you increase the salinity you should increase the production of salt so for me it could be a positive effect yes but to to gain the salt you have to remove the water if you cannot remove the water at the time water should be removed because it has been flat okay by flood okay okay no no it's clear and then the purpose of timing okay okay and you can also the social health impacts you can also have the cost of illness so you can also quantify some of them in term of them more or less you're right here are the market components except the worsening of thermal comfort which is more non-market for the buildings damages to building also which are non-market all the ecological impacts and the two components that are related to thermal comfort there are no markets for thermal comfort and these are mixed the health effects because we have seen yesterday that they are both market and non-market components excuse me just I have questions in which year the dam is built was built the dam yes in which year oh just after it started after the major flood and at the end of the 19th century and since that it has been improved changed rebuilt but it started 150 years ago I think this is the main problem when they built the dam they effect on climate change they change the nature of this area I think this is the essential one of the issue but without dam there are two types of dam along dam dam or you say you mean dam on the run yeah yeah dam on the run it's uh there there are geeks between the sea and the kamarik geeks along the run and there are dam uh upside the run and it was during the mid of the 20th century the largest dam on the run that provide hydroelectricity and that avoid flood due to the run of the neurons have been built in the middle of the 20th century but the geeks that protect kamarik from the sea or from flood from the run was at the end of the 19th century okay thanks I would like to continue his argument how to distinguish the impact of dam and climate change on changing the wetland scenario of the no the dam are another uh impact that add to boost of climate change in this case for kamarik the fact that the dam does not allows allusion to enter the kamarik and to replace what the sea gains on the on the the ground you see that it's an additional effect the three main effects of climate change was sea level rise the two uh the bit of the run and also flash flood kind of flash flood and then in addition there are the kamarik is sinking and uh there are less olivium coming due to the dam so I think uh I will quickly show what have been the damages of the last flood major flood in 2003 for agriculture it has been assessed to be about 80 million euros for industry about 367 million euros and damages to building an infrastructure were about uh overall uh 400 million euros with a total of one uh of for eight hundred 47 million euros for the last flood and then uh we can see all the areas that were flood in 2003 all the colored area were flood depending on the nature of the area there are different colors but all this area were flood and requires month before uh being uh as uh before the flood I think I will skip the two scenarios and you have it on the just stop here stop here here we can assess what would be the adaptation measures to limit the consequences of climate climate change by uh developing dykes along the run uh and the cost would be around 300 million and to secure all the dicks along the kamarik that is 210 and 10 kilometers of dykes it is estimated at about 800 million and then how a small benefit a little benefit cost analysis would work would be to compute the benefits that is what would be the damages avoided if we construct these dykes so for a type of flood and for a given period for instance one century we compute the benefits avoided in the event of uh backfill failure bridge in upper or overflow in the run despite development at different places let to sum up what would be the benefits if we avoid a flood we take into account the probability of occurrence of each of these events a flood of uh period of uh observation one century uh millennial flood and so on and how would resist the dykes against this type of flood so we compute the probability of occurrence of each of these events flood not flood for each of these flood we do this calculation for different types of flood with corresponding probability of occurrence that would be the benefits that is the damages avoided then we compute what would be the mitigation cost by evaluating all the work of securing dykes and concerted management of the river over the same period and then we choose a discount rate to express this flow of benefit and cost streams in net present value because you will observe the mitigation cost today you implement policies to secure uh the dykes and to manage properly the dyke but the benefits up to the next flood you will have no benefit it is in the event of the next major flood that would be avoided that you would observe benefits by not having damages so in conclusion and this is the last slide Camargue is an area externally exposed to climate change which translates into increased risk of flooding by flood or runoff and aggravated by rising sea level the economic assessments of the effects of climate change involve a large number of sectors we have seen and in addition they are non-market impacts associated with the degradation of ecosystem and water resources that have not been accounted for in these analysis as well as non-market health related effects like psychological effects of flood, fear, health effects of this type did not enter their analysis here finally the the evaluation of the cost of damages associated with floods makes it possible to establish the order of magnitude of the benefits to be expected from decrease in the probabilities of flooding whether it is through the implementation of global policies to limit climate change limiting the CO2 emission to limit the increase in temperature or to local policies to attenuate the effect of climate change the consequences of climate change by implementing and improving the dykes and the the management of the dykes this is these are policies that attenuate the effect of climate change and the global policies that limit emissions are another type of of emissions and both concur to to reduce the consequences of climate change in every place and here in Camargue okay thank you so we may spray okay I have a question or due to the degradation of wetland because of the climate change is there any impact on water quality into the poor water quality like in Camargue effects on the Rhone river which is which one of the best we can say not best largest river in the south france so just I would like to know what is the water quality effects because of the degradation of the wetlands because of the climate change could you a little bit explain about this whether water quality is the water quality is affected by climate change through the it was mentioned earlier by one of your colleagues the fact that there are self-perrifying properties of wetland areas so that the quality of the water that get out of from these wetland areas are better so this has been observed and this is one of the components which is accounted for in this type of analysis especially just I would like to know this especially for the Rhone river Rhone river or south france I know everywhere but I couldn't see any points in your conclusion about the water quality degradation due to the these effects climate change that's why I asked okay thank you I got it you have shown that many approaches to estimate the the climate change cost however the input data that you have used for construction your approach are mainly doubly because it is statistical data so there are any techniques or approach to improve your input data to to reduce the uncertainty that you have found in your estimation okay which one you showed some picture what the uncertainty relationship to estimation is huge yes okay but the point is that there are many sources of uncertainties so that it depends on the assumption and the type of model and the type of simulation that are implemented so under a given set of assumption we can reduce uncertainties because we have common assumption but as soon as we take into account several the whole range of possibilities by definition the uncertainty is going to increase so it's all it's still be it still is a statistical approach because you you you simulate models million and million times and then you get a values range of results and then you choose a 95 percent confidence interval for instance to express uncertainty or you say very likely and not likely but I agree with you on the fact that it is a statistical uncertainty finally that you get because you have a distribution of values and you have properties of this distribution but at the origin it is due to the assumption that have been done so to reduce the uncertainty by reducing the set of assumptions you have the risk to to miss what is in fact the the set of assumptions that is the most close to what could be in the future so there's a trade-off on reducing uncertainty and being false being wrong in the conclusion and we will only know whether or not we are wrong in 50 years or one century so if we do not account for that when taking the decision today it's it's a risk thank you for your lectures just I would like to know are there any solution for Kamaro until now are there any someone put some solution for this problem to be honest no no and even what is done it's just a matter of acceptability social activity acceptability because the main city i cannot come back the main city is saint marie de la mer which is close to the sea and this it has been protected by dykes more and more and specific likes in the sea and around the city to protect the city which is a huge place where of religious place every year there is a big so for okay big religious place in addition to having tourism and people living there and the fact you protect this city worsen the effect of climate change and the rise of sea level around the cities so in in a few decades you will have like morse Michel in France the city of st marie de la mer here and then what are all around were not protected and some of of courageous politicians say we should start to think of uh letting the the sea uh suppress the city but there's also very old church and so on so it's difficult to accept for the population for politicians but scientists say this city is lost in two or three centuries thank you so maybe we could have lunch now let's talk thank you very much olivier