 Good afternoon everyone. Today I will talk little bit for different topic which I teach in my course in my environmental studies course here at IIT. It is about global warming and climate change you know this is a kind of a topic which everyone of us is talking about everyone has an opinion some in on right side some on the left side and also very important to you know the if you if you talk to any environmental engineer environmental scientist or climate scientist for across the globe. So, this is the most critical issue which has come up in terms of environment in terms of survival of our whole humanity actually. So, we will talk about that today and in addition more importantly that if that is the issue that is existing that what can we do and what is the realistic situation you know when we talk about global warming and climate change then people say we should plant tree then we should go vegetarian we should you know cycle by yeah that is true there are many options but then we have to take a realistic view that what actually is a situation what is the extent of the problems. So, that that is what I will try to cover that will I will talk in this lecture today what is global warming what is climate change and what is the solution what are the potential solution for to solve this problem that is what we will talk today. So, global warming it refers to the rise in global temperature near the earth earth surface what is global warming basically it is basically saying that the temperature or the earth is warming right as simple as that then there is another term which is called climate change then ultimately it is it is understood or it is many of scientists believe that global warming actually is leading to the climate change and global warming in itself represents only one aspect of climate change for example if the climate change happened there are several consequences of other things which will happen but it is understood that this climate change is happening because of global warming and what is climate change then then it means any major changes in temperature precipitation or wind pattern and other effects that occurs in a considerable amount okay that means they are major one probably not the minor one. Do we believe do we think that the climate change is happening of course many of scientists believe so and you will know or if you start searching what any kind of disasters happening you will find that there are several of disasters happening for example extreme weather events which is happening now more commonly as were happening that is a 50 years ago or 100 years ago and we have evidences which shows that the sea level has rise the global temperature has rise in last 100 years the oceans are warming the ice sheets and the snow covers are shrinking there is a decline in the Arctic sea ice level so these are a few of the evidences tells us that the climate change is happening so as I mentioned the in the last 100 years or so it is calculated or it is known by some measurements that approximately 1.54 degree Fahrenheit temperature has increased the average if we talk about the average earth's temperature it is not uniform it is not everywhere it will be same in some places it may be high it may be in other places it may be low and you know it is very difficult to project what will happen in future because earth is not a very simple model when we talk about projection when we talk about modeling then we should have a system in which we use many assumption we simplified it. So to model in earth as a whole system is not so simple but nevertheless many of scientists believe that the temperature could increase as high as 11.5 degree Fahrenheit or it may be just 2 degree Fahrenheit so it should be in between 2 to 11.5 degree Fahrenheit as per many of the models it is not as simple as that understanding that okay if the temperature increase by 2 degree Fahrenheit I increase little bit of my air conditioner and I should be okay or it is just like yesterday it was 30 degree centigrade and then today is 31 degree centigrade it is not like that you know the small changes even in the temperature would lead huge change in the climate that may be potentially dangerous and it may lead to further so think of this think of this that in Rajasthan it starts having snowfall and if there is no rain in Mumbai in the month of June so that are we prepared for both probably not okay so that is kind of thing that even it will be changes we need to think about changing our infrastructure we need to think of changing our whole design of the buildings how we live how we deal with the different things okay so it is not that simplified that 1 degree Fahrenheit I do not care I just increase my AC little bit and I should be okay so that is not that simplified. Even a few even half degree Fahrenheit change in average earth temperature would can lead to catastrophe so that is more important than just thinking that it is just 1 degree Fahrenheit or even less than that 99% 97 you know many of you may be thinking that oh I know that there was a article in newspaper they say that this is an hoax story there is no reality there is no evidences of climate change happening no global warming people scientist 50 years ago said that actually the earth is cooling now they are saying it is warming but 97% of the climate scientist has agreed that the climate warming over the last 100 years are very likely due to human activity that means whatever this climate change is happening global warming is happening this very likely is due to human activity that means the human anthropogenic reasons are the reasons for happening this and most of the leading scientific organizations worldwide including many of science academies have issued public statements endorsing this position that the climate change vis-a-vis global warming is happening intergovernment panel on climate change IPCC they say that scientific evidence of warming of the climate system is unequivocal that means we know that this global warming as climate change is happening you see this this figure taken from IPCC it will probably it may not be that clear but you can go to this climate change 2014 synthesis report and in fact it is a synthesis report it then there is a complete exhaustive report published in last year which tells you what is update on climate change the IPCC keep on updating the information available and the scientific knowledge available the solution available upon climate change so if you see the average temperature on the earth surface is increasing and more so in last 100 years or so and it is also showing that the average sea level has changed sea level has changed in last 100 years or so they also have shown that the greenhouse gases which is carbon dioxide which is NOx which is methane and of course others also they have been considerably increased in last 200 years or so especially after the industrial era after 1850 or more so in after 1950 and it also shows this the fourth graph the graph D also shows that the most of these greenhouse gases are coming from use of fossil fuels use of other anthropogenic activities a very few actually is coming from the land use etc and from the deforestation and other kind of activities that means there is a considerable increase in greenhouse gases which are emitted by anthropogenic reasons for example from the combustion of a burning of fossil fuels and there is also increase in sea level there is also increase in the average earth's temperature if you see this the greenhouse gases concentration especially carbon dioxide methane and nitroxide they are the maximum in the last 800,000 years that means it simply tells that that in our atmosphere these greenhouse gases CO2 methane and nitrous oxide they have achieved the maximum concentration which was never before even in last 800,000 years so that means that these greenhouse gases are probably causing the global warming and it is written that extremely likely to have been with the dominant cause of the observed warming since the mid 20th century in this kind of system in this kind of big model like earth it is highly it is very difficult to just say with 100% accuracy that okay this is the only reason but they say that it is extremely likely that this global warming is happening due to the greenhouse gases. So why do they think this is the case because if you see understand the greenhouse gas effect or greenhouse effect this is a known science that there is no much confusion understanding that what is a greenhouse effect this is a known science and if you just take this simplified picture it shows that the sun radiations they come they reach in the atmosphere and some of them are reflected back and remaining a good amount of them also are reflected by earth surface and half of them are actually absorbed by earth and a good amount of radiations are reflected by radiated by the earth and when these the radiations are coming in they are mostly in the visible radiation mode that means their frequency is their wavelength in the lower side but when they are released when they are radiated from the earth their frequency sorry their wavelength is on the higher side that means they are largely the infrared radiations. So when the infrared radiation that reaches in the atmosphere so these greenhouse gases along with clouds etc they part of these radiations are reflected in all directions some of them actually escape back to the atmosphere but some one of them which are reflected actually first absorbed and then reflected or radiated back by the greenhouse gases they come back and remain in the atmosphere and then lead to the earth's warming as well as maintaining the earth's temperature. So this science is known the greenhouse effect the greenhouse gases are known in fact you many of the scientists have done experiments on this so they are there for many years even in fact you may be knowing the water vapor is the biggest greenhouse gas but what has happened is because of their increase the impact has increased if we do not have any greenhouse gas effect if we do not have any greenhouse gases we probably cannot live in on earth the earth will simply will be just and on the ice ice age side. So this whatever temperature whatever this nice temperature we are having in many places it is because of these greenhouse gases the problem has arisen because of the increase in these greenhouse gases. So this greenhouse gas effect is science is known and then if I when I show you the when I have shown you the last slide told that these emissions are increasing. So we know what is greenhouse gas effect and we also know that these greenhouse gases have increased in the atmosphere that means probably the warming is happening because of the increase or the additional greenhouse gases and most of these greenhouse gases additional greenhouse gases actually are emitted because of the anthropogenic sources. So that is why most likely most of the scientists believe that greenhouse gases are the cause of global warming and in fact it is kind of a believed by most of scientists as I mentioned 97 percent of them. If the global warming is happening and if it is due to greenhouse gases then the simple question is that how we can reduce those greenhouse gas emissions. So the technologies which can be used or can be used to reduce greenhouse gas emissions are actually called green technology you may be reading now and then that every now and then we are now talking about technology which is called green technology or sometime you will see that go green. So if you Google green technology in your Google images that is what I have done you will find this kind of picture very interesting so many pictures but there are a few there are a few things which is very clear one is that it is a green color everything is green and if you see most of them it is all it is also related to analogy for example it is about the wind generation it is what are different kind of bulbs etc. So that means when we talk about green technology simply is related to the analogy we will talk about that why it is so and if you try to identify what is the definition of green technology it is actually any technology any application of technology which reduces the greenhouse gas emissions which probably reduces the use of natural reservoirs which probably improve air and water quality so in fact this green technology can be seen in different perspective in fact you can call them actually environmental technology or sometime they are also called clean technology. So either you reduce greenhouse gas emissions either you reduce pollution either you reduce the use of natural sources anything will fall any technology will fall under the green technology. So for example if I start doing recycling if I treat water I purify air I use sewage treatment all these technologies environmental degradation for a waste management even in fact renewal energy energy conservation etc will fall under the concept of green technology. But for with the perspective of global warming the any technologies here we will discuss is with the perspective that which reduces greenhouse gas emissions. So we are defining here the technologies which are reducing greenhouse gas emissions that is what we are considering for only for this class is the green technology. Let us start talking about what are the different technologies and how and how much they can be implemented let me take a few questions so that you know which I just want to take your opinion what you think about global warming is it a true case or it is you believe in global warming or you do not believe in global warming. So let us go to few colleges. So Silguri Institute of Technology what do you think about global warming is this happening global warming climate change is happening. Yes sir global warming is happening sir and we are having this adverse effect on us also like temperature rise and also different kind of things which is happening all around the environment sir who is there yes I do believe in global warming. Good afternoon sir I just want to tell you about whether global warming I believe it or not actually global warming is a natural phenomenon actually without global warming also the temperature of the earth could not be like this in the comfortable range so we need global warming but excessive carbon dioxide and other greenhouse gases causes some rise in temperature so to some extent extend civilization affecting the environment that's my point is but global warming is a natural phenomenon it's been there for last from the inception of the earth I think according to me okay thank you sir. Development in the country so sir can you please comment on that. So I would say that you it will have a huge impact and why do I believe that because you know many of I would say that a good amount of our cities or good amount of our states are on the coastal region. So if the sea level and extreme weather events start happening of course the straight way will be affected okay and global warming leads to extreme weather conditions in a country where a good large population is poor in under poverty which are you know there are these people who are who doesn't have good resources are there more vulnerable to all these climate change etc. So then you can think that many of us will be affected certainly so I would say that if you compare it with the 12th country our country will be affected more I am not talking about individual country by country basis but because of our coastal areas because of our you know even in fact if you see the good part of India it's already a temperature always remain high okay so then think of even increasing in temperature but in that way certainly as actually we are more vulnerable all countries for population many a good amount of population is towards the lower income side is certainly and highly will be affected by global warming because of climate change. So you believe in global warming that's my question to you whole group you think it's a real thing SR SR yeah so you believe that global warming is happening okay all right then we go back to the slides it looks that most of you agree which why the by the way was not the case when I was teaching this to my students they had different opinions but you know the most of the scientific community in fact believes that global warming is happening due to greenhouse gases. So you know then the important question is that if greenhouse gases emissions are increasing then what to do and then I told about green technologies and all these technologies in fact someone was just talking about the photovoltaic in fact any technology which we used and reduce greenhouse gases it certainly would be called a green technology. So the important one are solar energy between thermal power plants between photovoltaic power plants and then wind energy nuclear biomass hydropower geothermal energy everything in fact even energy efficiency those all technologies can be called green technology okay. So in fact if we adopt all these technologies they certainly are green technologies there are questions to how to implement then there are questions about the economics for example if I have to have solar if I have to have wind then it's like that the sun comes in the daytime the wind blows when it has to blow okay. So then it's question that what will happen if the sun is not there or wind is not blowing then that means we need to have some kind of storage energy storage systems along with that or you have to use it with something else for example with biomass for example with in connection with hydropower etc etc okay. So for example if I have a coal power plant it I can run I can get my energy for let us say 90% of the time if I have a solar power plant if I have to calculate to get the maximum energy that probably that will be 30% of time 40% of time similarly with the wind depending on where you are. Then another technologies is nuclear a good technology you can either love it or hate it because it has many positive things and it has also many concerns you know for example about the radiation what the nuclear ways there are lot of many concerns also okay. So but the carbon footprint of its nuclear technologies are very low and we will talk about that little bit later but at the same time there are another environmental issues associated with that okay. Hydropower of course it is it has also very low carbon footprints it has low or no CO2 emissions but there have been concern that how this hydropower and then also the reservoirs and the whole ecosystem are in the surrounding areas affected by those hydropower. So that need to be seen case to case basis okay and you know you will see that across the globe good amount of I would say a good hydropower actually is harnessed. So therefore there is no much scope in going further I would say that it can increase in countries like India but probably in countries like US they already have harnessed the most of it. So there is because our energy demand is increasing but then we have this limited resources of hydro power etc. So we cannot expand that is another question. Then the there is another technology which is called geothermal energy of course geothermal energy is the extraction of heat from the earth's crust and then you know running it to produce energy on someone on like the thermal power plants. That is also possible not in all countries but in a few countries for example in India we do not have many options if even if we have some option for example I think in Chattisgarh they are attempting some but it has a very limited scope okay. So that means does not mean that it will change the whole energy use scenario. Many people think and actually that is true also the biomass is also a has a very low carbon footprint. So why it is so for example what happens if I grow biomass it in the presence of sunlight by photosynthesis it takes carbon from that atmosphere takes CO2 from that atmosphere and then the CO2 is fixed in terms of biomass and then I burn it or then I use it for energy production and then again it is converted into CO2. So if I am able to produce the amount of biomass the amount of biomass equal to the amount of biomass I am using for biofuel or burning it for bioenergy then this can be called carbon cycle because in terms of the net CO2 emission it won't increase the net CO2 in the atmosphere okay but then if we are using more but producing less then slowly slowly it will be then it won't be carbon neutral and then it in fact it will affect other ecosystems also okay. So all these technologies actually can be called green technologies and they will certainly reduce the greenhouse gases okay. So that means we have to try for all these technologies. So if I see the different greenhouse gas emissions from different fuels this if you see if I use lignite or if I use coal if I use want to produce one unit of electricity which actually is 1 kilowatt hours it will approximately produce 1 kilogram of CO2 that means 1 kilogram of CO2 will be emitted to that atmosphere. If I use natural gas it is approximately 500 grams that means if I use coal power plant it will be approximately 1 kilogram but if I use natural gas power plant it will be half of the coal power plant. If I use solar if I use biomass if I use nuclear if I use hydroelectric they are greenhouse gas emissions the life cycle greenhouse gas emission is I would say negligible as compared to coal etc and it is very low. So if we want to reduce our greenhouse gases considerably so we have to adopt for these technology and we have to get away from these technologies okay. However if you see our energy use most of our energy across the globe is produced from oil the green one is our oil and then the natural gas and then the coal if you see up to here I would say that 90 percent or so our energy across the globe in all form of energy is actually produced from fossil fuel be it be natural gas be it be coal or be it be oil and very less let us say 2 3 4 I do not know how much but let us say 3 4 percent is hydroelectric and the remaining biofuel is still very low. The scientist who has projected it further even the way it is happening the solar the wind geothermal has will have a role to play in future but that is not that much because our energy demand is also increasing. So if we do not have any major changes in our policy in our use etc our energy production probably our energy use will still remain from the fossil fuels okay. This was this is about total energy if I talk about electricity across the globe you will see that it is again also from the fossil fuel a good amount of course from nuclear and then the renewable. So still our fossil fuels are playing major role and if I just project it further probably still they will play the major role okay. So that means all these electricity types are fossil fuel based and they generate huge amount of greenhouse gases be it coal be it be lignite be it be natural gas be it be oil but those who do not generate much we are not using them much. So in fact we need to kind of shift the wheel which probably is not so simple you know in fact if thinking of that that 80% of that probably coming from fossil fuel if not let us say even less than that but then switch everything with renewable and nuclear etc in in the coming future won't be so easy okay. So that means we still have a challenge that how we can reduce our greenhouse gases because of course the renewable will play a role but how fast they can play role is need to be seen okay. So and this is the global anthropogenic carbon emissions please remember that when we talking about greenhouse gas emissions we always calculate them in terms of the CO2 equivalent because greenhouse gases have different global warming potential that means for example if I have methane it is 21 times more globally potent globally warming potent as compared to your CO2 okay. So we always calculate in terms of equivalent and sometime we measure them in terms of CO2 sometime we just measure in terms of carbon emissions. So here when I am talking about global anthropogenic emissions it is basically carbon emissions okay. So the total carbon emissions as of today probably is 8 billion tons or 9 billion tons out of that 9 billion tons approximately 3.5 is coming from coal and approximately 3.5 is coming from petroleum 1.5 or so is coming from natural gas and very less let us say less than 0.5 is coming from cement production very little from gas flaring. So that means if I talk about anthropogenic emissions and I want to reduce it I have to tackle petroleum I have to tackle coal and I have tackle natural gas because they are contributing most of it the remaining is pretty low actually okay. It is actually negligible right of course cement production has significant amount 0.5 billion tons of carbon. So that means we have to tackle this but as a matter of fact because most of our energy is coming from these resources so it is kind of a difficult situation we are in a difficult situation that how to deal with this. There is a one concept which is now tried in some places and then is called carbon capture and storage you must have heard or sometime it is called carbon capture and sequestration. So I just leave you with this figure for a minute so that you try to understand what it is what is shown in a figure and then thus I will try to explain it actually okay. So please one minute please understand try to understand what it is shown in the figure. So basically carbon capture and storage is a concept of capturing CO2 from large point sources such as coal power plant such as natural gas power plant such as from the cement industries and sequestrating or putting it under the ground. So when I say underground it is the thinking is something like similar to what was the natural gas you know the natural gas is lying underground for 1000 of years if not more than that that means there is a possibility of even putting CO2 under the ground that means there is possibility that it will be placed it can remain under the ground similar in the line of the CO in the natural gas. So what do we do in this concept be our large power plants for example they are producing CO2 but those emissions which are coming out they along with that they have another gases for example nitrogen and remain a few pollutants okay and even sometime oxygen also. So what we do is separate this CO2 from other flue gases coming for example from coal power plant and then putting it underground okay for example if you see here putting it underground dig a well. So what is the possibility that my power plant may be at x place but where I can dig a well and put may be at different place why it is so because it is not that all formation all kind of places I can store it I can put it underground it need to be a kind of formation which has a cap kind of rock which is impervious on the top of it and which has a kind of strata in which I can put it and probably then it should remain there okay for example if it is a gas field which is a depleted gas field already I have extracted CO2 out of it I can put it there and for example there is an aquifer where it is not the fresh water aquifer but the saline water aquifer and that is much below the earth let us say 800 meter or 1000 meters below I can put it there. So that is the concept I capture it transport it so basically if I have to transport you can understand what is the density of CO2 then it means if I will transport it further away I need to in fact compress it so I capture it I compress it and then I transport it to a place where I can put it underground dig a well and put it there. So that concept is called carbon capture and storage you know so what is the idea that crystal can use fossil fuel with power plants but at the same time instead of that CO2 going to the atmosphere it is we are putting it under the ground so that it is not leading to the global okay so because it is not increasing the concentration in the atmosphere. So this is another slide showing that how can be so the first component is for example I mentioned the capture or separating so how can we do that so in fact we have some technologies available so this is for example a power plant we are burning coal in the air and then we produce flue gases which is nitrogen which is oxygen and CO2. So if I can use technology to separate that CO2 from other gases I can compress it and store under the ground okay so this is called post combustion I in fact we have absorption as well as absorption based technologies which can be used actually any of them are even available on a commercial scale and then put it underground. Similarly we have another technology which is called pre combustion so what is the concept in instead of using doing that the combustion directly we gasify our fuel for example if you remember I told yesterday that I can gasify solid waste I can even gasify the coal and once I gasify it is converted into carbon monoxide and hydrogen which is called synthetic gas and that carbon monoxide and hydrogen is further converted into CO2 and hydrogen by using a water steam reforming it is called steam reforming in steam reforming we use steam and then we use carbon monoxide so carbon monoxide plus water it is converting to carbon dioxide and hydrogen that means we already has hydrogen coming from synthetic fuel plus more hydrogen coming from steam reforming that hydrogen you all of you know it is a fuel and then once we separate this hydrogen from CO2 we can again put CO2 under the ground and use this hydrogen for as a direct fuel or even for generation of electricity or heat actually okay so that is the second concept then third one is oxy fuel combustion instead of so what happens is if I do combustion for example if I have a let us say very simple fuel like methane and if I do combustion I produce if is CH4 it is converted in presence of oxygen into CO2 and H2O but because if I am using air for combustion which is used in most of our cases it also produce it has the flue gases nitrogen so this whole nitrogen is need to be removed here but if I can just use oxygen for combustion instead of using air so I would not have this nitrogen in my flue gases I will have CO2 and I will have H2O which can be easily condensed and then this CO2 can be compressed or put it under the ground okay then even in some industrial processes we can use this for example you will you may be knowing that in many industries there is actually a separate steam of CO2 coming which otherwise leads to atmosphere if we can capture it and then we can sequester it. So if we do this carbon capture and storage probably we can still use the fossil fuels but at the same time the CO2 emission the greenhouse gas CO2 emission they won't go to the atmosphere so that is the whole idea that means still for some time we buy time basically we use fossil fuel but do not allow the greenhouse gases to go to the atmosphere. It is not that simple the way it looks like it will have energy penalty that means the additional energy for compression for separation even putting it under ground it will also cost a lot that means for if I have to produce if I was having a 500 megawatt electricity plant or coal power plant if I put a CO2 capture process on the that CO2 capture along with compression etc the probably it will reduce my capacity of plant of up to a 400 megawatt or even less than that maybe 350 megawatt. So what it means basically to produce same energy I may be using additional resources okay so that is kind of issue it will increase the cost of electricity generation that kind of concerns are there there is also concern that for example if I put it underground what will happen if it leaks if it go to the atmosphere then whole idea of you know whole this process is lost. So these kind of concerns are with the scientists they are working on that and trying to understand that what can be done but before I go I am seeing there are several people asking questions and in fact I also want to ask you a question so when I go to your center please answer this so what can we do actually to reduce our greenhouse gases what is your opinion on this KMEA Aluba Kerala please ask your question does the constant concrete building affects the rising temperature in atmosphere other than GS greenhouse gas emission okay and what is the other question the carbon dioxide concentration in the atmosphere is always increasing per year. So does the percentage of CO2 in the atmosphere increasing or decreasing or remaining the constant there is one more question also by implementing the carbon credit for industries in India can we reduce the greenhouse gas emissions from India we are not implementing that because in western countries especially in Germany they are implementing the carbon credit rating also most of the even developed countries especially all the European countries are on the path of implementation of carbon credit why we can't implement it very many industries okay so the first question was that concrete building is affecting the rise in temperature I do not know probably not I do not know how it it may be affecting the local temperature etc cement production yes cement production is increasing the greenhouse gas emissions about the carbon credits yeah so basically if you see that it can be implemented in India also we were also part of the CDM mechanism you see there should be incentives there should be incentives given either by government or so far under the CO2 protocol or the international agreement we have so far we were not supposed to reduce our emissions so if there is no incentive to reduce emissions industries won't pay for that but under the clean development mechanism under CO2 protocols there was there are many industries which reduces their carbon footprints and got carbon credits which were sold to the to the European annex I think annex one country that was done I forgot your second question actually what was second question the carbon dioxide concentration in atmosphere is increasing yes the but does the CO2 person the percentage of CO2 in atmosphere remaining the same no so if it's increasing it certainly is not remaining same it's not the all constant all gases are increasing in that most case the percentage wise also it's going out so so let me ask you a question then how can you reduce the greenhouse gas emissions by implementing green technologies and also the specially solar wind biomass hydropower and geothermal also by also adopting the carbon highly carbon crediting the efficiency of energy consumption industries can be reduced very good but how much of that is required and how much of that can be practically implemented any gas the I don't have any no no any other person sitting there any good idea if I want to reduce my greenhouse gases of the country no one oh there is another yeah thank you be good to some one another college Hindustan Institute of Technology good afternoon I want to answer your question yeah where the carbon dioxide can be used it is for the growing of plants in greenhouses or organic culture and also the growth of algae in the oceans and carbon trading go ahead go ahead I am listening hello so these ways the carbon dioxide used the sequestered carbon dioxide I mean and I want to ask also a question to you yeah can we use the green manufacturing also like you talked about the green technology in which you have talked about only the production of energy very good question place of energy we want to ask you if we have green manufacturing that certainly will also reduce emissions that is that is there but you see that green manufacturing also means the use of green energy there right because many of our industries basically tremendous amount of electricity so if we are producing electricity from green technology based sources eventually it means that we are doing the green manufacturing very good question yeah of course we can do it in the industries also there is one more question I would like to ask you sir though it is not a technical question but still can you throw some light on like it is more of a political angle on the other than actually we are worrying about the yes that is happening here I shouldn't say it's just a political thing but it is also and concerned for different countries that how to do how to deal with because you see this problem of greenhouse gases is a global problem right so it's not like I do it but then some other doesn't do it then it doesn't help okay so that means we need a consensus across the globe so to get that consensus there are several issues one is of course economy if you ask some country that reduce your coal power plants do not use coal power plant that means you are saying that do not use this kind of energy that kind of energy that eventually will affect the economy so to get the global consensus is not so easy so in that sense it's a political issue also it said it's you know it it will in fact change many things in across the countries if we take considerable steps to reduce emissions but in fact we also need to see that how many technologies are available you know it's not that simple that I say that all coal power plant will be reduced by wind and wind or something like that so that means that kind of scale of wind should be available and then the question comes about the cost of the electricity generation and then whether if I increase the cost by 2 times or 3 times whether it is affordable by individuals as households or also affordable by industry so it will change many things so basically it's not you know it's not so simple question okay so it is little bit of political about having a global political consensus and also because the political people across the globe are also they're right in a sense that because it will change the dynamics of the whole country so it cannot say why just stop and reduce my emission by 90% that won't happen in very simplest model thank you very much so you know the important point is that once we know that there is a problem which is more or less agreed by most of us then the question comes that how to solve talking about a problem is fine but talking about a problem forever is not a solution okay so we will talk about that what kind of solution can we envision what can be done and we will also talk about that what are the consequences okay for example if I say that I stop using coal power plant how feasible it is what it means okay so there is there are a couple of famous scientists in Princeton University Professor Robert Sokolo and Stephen Prekela in fact they wrote a research paper in august 2004 and I think it was the name of the paper was stabilization basis solving the climate problem for the next 50 years with current technologies it was published in science science is a very renowned journal actually one of the best journal in academics so they wrote a research paper and based on that there are several presentations made several in fact games made several presentation even by put by by the Princeton University on their website by carbon mitigation initiative in the Princeton University so the idea to show this to you is you know giving a sense that how much is enough what is required is it just what growing a few more trees will it solve the problem because they can then we are talking about the natural sequestration or is it too much what is actually required so the few slides next 10 or so slide which I am showing is by carbon mitigation initiative by Princeton University I should would like to thank them and just to give you perspective that what kind of solution we can think of okay so if you see the emissions the carbon emissions again I am talking here about carbon carbon not about carbon dioxide so approximately we are emitting 8 billion tons of carbon every year okay and if you see in the last in the historical it is increasing for last 50 or even 58 or 60 years if we keep on doing what we are doing which is called business as usual not thinking much on changing drastically what our energy use etc and thinking our economy growth not individual Indian economy but a global economy the people becoming richer etc affordability of many things happening our total emissions in next 50 years or so will be almost double from what is today that means we are emitting 8 billion tons of carbon today we will emit approximately 16 billion tons of carbon every year in let us say in 2060 or so so that means if we follow the current path we will reach here in next 50 year in terms of our CO2 emissions so if we follow this path the concentration of CO2 in the atmosphere will be 850 ppm that is an easy target and then after 50 years the technology will be well further than we think of what to do and that is the easiest step because we do not have to shift we do not have to challenge our self much we do not have to challenge our energies the way of energy use much but if we think that we decide from today onwards that we want allow our greenhouse gases to increase further that means what we are emitting today we just keep on emitting that but at the same time our energy use will increase so that means there is a deficit there is a complete this triangle these amount of emissions need to be reduced because certainly our total energy use will increase further. So if we can take this path which is called flat path do not allow the emissions to increase further whatever we are emitting today just emit that and after 50 years it does not mean that our greenhouse that they want be any global warming or climate change we still have to take further critical steps after 50 years so and if we do so then maybe in in 20 70 or so our emissions our CO2 concentration in that atmosphere will be approximately 500 ppm which many of scientists think that we should target one you know many of scientists already think that whatever emissions whatever already we have emitted certainly this global warming will happen but what is acceptable the acceptable they say that we should try to make sure that it does not increase by 1 or 2 degree centigrade. So by doing this by taking this flat path and then reducing the emissions further we probably will you can stabilize greenhouse CO2 in the atmosphere in the range of 500 ppm or so that should be acceptable in many ways. So that means if I just want to take this path I have to reduce this much of additional CO2 otherwise they will happen. So these these two scientists they divided this into eight wedges of each of one unit height that means there are eight wedges which we need to to find solution for. So when I say one wedge it basically means the here 1 gigaton carbon and the time frame is 50 years that means in one wedge I have to reduce 25 gigatons of carbon and in fact I need eight wedges of like that that means it is approximately 200 gigatons of carbon I need to reduce in next 50 years so that I am here I am on the flat path that means all the additional 200 gigatons of carbon need to be reduced in future okay in next 50 years. So the question is how can we do that okay so these eminent professors they they give 15 wedge strategies or 15 solutions and they categorize into four categories. One is called energy efficiency and conservation second was nuclear power third was renewal and bio storage and the fourth one was fossil fuel waste strategies that means they said there are at least 15 strategies available and remember we just need eight of out of them so that we will be just on the flat path we will not increase our CO2 emissions in next 50 years or so. So what are the different options for example in terms of efficiency if we can produce twice today's quantity of coal waste electricity at 60 percent efficiency that means we almost double our coal power plants efficiency today our coal power plant efficiency on the average on across the globe is 32 percent. So if we want to get one badge that means one triangle we just have to reduce it we have to increase the efficiency to almost double when I say the double it probably also include that we are using doing cogeneration we are also producing some steam instead of and replacing the direct use of electricity. Second option is double the fuel efficiency of the world's car that means if my car is traveling 8 kilometer in a liter in next 50 years so it should travel 16 kilometers in a liter which looks little bit of difficult either we have to switch to small cars or we need to increase the efficiency. Another part of another flip of this is that if we just travel half what we are traveling today because what will happen the cars number of cars will increase so if we reduce the half of our miles travel that means it actually has the same meaning as of increasing the efficiency. So also use the best efficiency practices in all residential and commercial building that means wherever we are using air conditioning where we are using heating systems we use the best practices available that means use the most efficient systems that also can give us a wedge and that means across the globe. Just to put a perspective if we replace all of our incandensed bulbs across the globe you know what are incandensed bulbs ordinary 10 rupees bulb which we were using for several years in fact we are now replacing them with CFLs or even with the LED lights it simply will give me one fourth of the wedge that means even by replacing all the bulbs across the globe that bond even give me one wedge okay so that means it is a really a huge challenge it is not that it can be done simply in the simplifier but it is possible because these technologies are available at some scale. Another option is called fuse switching for example you as I mentioned that if I use coal power plants I produce approximately 1 kilogram of CO2 for each unit of electricity generated but if I use natural gas it is 500 grams that means half of CO2 emission as compared to the coal power plant. So if I switch 1400 gigawatt of natural gas for 1400 gigawatt of coal power plant that means I have 1400 gigawatt of coal power plants in the future and I replace them with this 1400 gigawatt of natural gas my I will get one wedge of greenhouse gas emission reduction but what it means practically it practically means that I am doubling the natural gas used in next 50 years or so that means the question will come that how we can extract that much of additional increase on natural gas or is it even available or not that kind of question need to be answered. Then the another solution they mentioned is carbon capture and storage as I mentioned what carbon capture and storage if we can put carbon capture and storage on 800 gigawatt of coal electric plants or 600 gigawatt of natural gas electric power plants or maybe produce synthetic fuel from 180 coal power plants or increase hydrogen plants by 10 times of today's capacity that also will give us each these of category will also give us one batch but as I mentioned that this carbon capture and storage is not commercialized that much I mean capturing of course but not in totality we do not have much experience we just have three major projects across the globe which actually are capturing 1 million ton of CO2 per year and by next 50 years or so we have to increase them by 3500 that means we have to go from 3 plants to 3500 plants that is that is huge actually. Then the third category it says the nuclear energy we can if we can increase the nuclear production and the nuclear use nuclear electricity production capacity by three times in next 50 years but this is highly unlikely because you may be knowing that many of the countries in fact they are going away from nuclear you may be knowing that Japan has gone nuclear free Germany says they want to use in future and there are issues with the nuclear use in terms of the policy. There are many countries saying that we do not use nuclear further so to find to understand that it will be three times of today's capacity it is going to be very difficult wind of course that is possible but we have to increase the wind capacity by 10 times in next 50 years that will be too much but I personally think that is really doable the way the wind production the wind electricity or the wind turbine we are increasing across the globe that should be doable but we have to increase it by 10 times in next 50 years. Similarly solar one we have to increase it by 100 times that means whatever solar electricity we are generating today we have to increase it by 100 times in future so then question is what the cost how much it will cost but nevertheless the technology is available. Then as I mentioned about the biofuels reduce our use of the fossil fuels and replace them by biofuels that is possible you will get one batch but we have to increase our ethanol production global ethanol production by 12 times. So that means we have to increase it 12 times if we are saying that we have to increase it by 12 times which basically means that we are seeking additional area either we replace the agricultural land which is not a viable solution not practical or get additional area which I do not know where that area is and to grow that increase this ethanol production by 12 times which basically means have ethanol production from the area equivalent to the area or size of the our whole country our India that need to be seen we do not have that much across the globe we do not have that additional area so the practicality need to be seen. So what we are trying to find here is that it is not so simple first of all and even if you see we need eight badges or so and even to get one batch we need tremendous amount of additional area we need to increase wind power by 10 we need to increase solar by 100 we need to increase nuclear by three times we need to increase the efficiency by twice that is huge actually it is not only that we say that we grow a few trees and you know I do not know a few small changes want be enough actually that means they need to be a major change in policy major changes in the energy use that is required okay and then natural sinks many people talk about natural sinks that forestation a forestation can can help of course if we can grow new forest equivalent to the continental US that means if in the whole area equivalent of US if we grow trees new forest that will just give us one badge and remember we just need eight badges so that means you know the forestation is a good idea but it certainly want just only forestation wants all that problem another idea is eliminate all kind of tropical deforestation use conservation tillage basically conservation you may be knowing what is conservation tillage basically means that whenever your crop fruit is removed you do not remove the scrap you keep the residue of the crop inside the soil itself and it acts as a fertilizer it acts as a bio storage for the timing and that can be done but remember that only 10 percent of the global crop is produced from conservation tillage otherwise we do not use conservation tillage across the globe. So these kinds of solutions are there there will be repercussion in terms of in terms of the cost there will be repercussion in terms of whether these technologies are available whether they are scalable but at in in many incidents in some way these technologies are there some but not commercialized or very highest level but either some are commercialized some are demonstrated or in that sense they are there. So this is the take home message I already have explained this basically it tells that you know we need to deploy low carbon energy technologies it has will have repercussion in terms of the cost it is doable but the scale need to be seen. So this is my last slide this is a very famous scientist Gavin Schemt he just I am quoting him he said if you ask a scientist how much more CO2 do you think we should add to the atmosphere the answer is going to be none and all the rest is economics that means in fact we should not emit CO2 but only the question is how can we do it that means it is a question of economics if you if I want to switch from coal or something else to a sophisticated technology some of them are really expensive so and the scaling there are issues regarding that okay so that is why he says that everything is all about economics okay so with this I stop my lecture we will have 10 minutes for question and answer than introduction so we will go to few centers. Sir regarding the carbon sequestration in deep underground strata sir will it not be like like storing something deep inside the strata that can sometime come back and like you know it will be like a huge explosion of carbon dioxide after a long period of time so that will be like an atomic bomb that we are storing somewhere inside the very good question won't be atomic bomb certainly but there are questions whether it can leak out or not but if you see that it will be it is not that I store it under the ground and forget it it need to be monitored first of all it start with finding a suitable storage where it can be stored for a long time that it does not leak and after that once we store it we have to monitor it may be of course for many many hundred years etc okay so the whole geology of the area need to be known to a very fine scale and after that we have to choose a few very few fights will be suitable for that and only then we can store it the question is whether it will leak out and the way you you are assuming most likely no because if you find the right side we we keep on monitoring there are sophisticated sensors on that we keep on seeing whether the leakage has started or not there is no doubt that or there is a concern among the scientists that it can leak but that need to be monitored and in fact that can be controlled because the analogy is that even natural gas is stored under the ground right and it is not leading to something like a catastrophe it is there it is there it is not coming every day and if we have to in fact extract it okay so that is my answer to this wales university Tamil Nadu how to manage the greenhouse gases effect so what do you mean by managing greenhouse gas it is without using no renewable reservoir is there any other techniques to resolve this problem yes I mentioned about carbon capture and storage is it possible to remove the carbon dioxide by any other techniques well it is possible but the question is that how much it will cost and how much it can be scaled up so it is possible but there are certain challenges certain issues regarding that the best way is not to use fossil fuels at first place but that practically is not possible so then we have slowly slowly to build on on renewable slowly slowly build on other options carbon capture and storage could be one of them and we have to see how it comes up actually carbon dioxide having that is it is possible to sink in water right so is there any other method to sink the carbon dioxide with water and forming any other any other gases or there is a pregnant yeah it can be dissolved in water the concentration will be really less because then it will lead to the saturation in there there are many bays of even converting into minerals etc the question is that how many minerals how much mineralization we can do you know it is little bit difficult but nevertheless we have all different possibilities we have to keep on trying that how far the IPCC progress in climate change is used well IPCC has it is basically an body it is a it is a body which tells us what is the status of the different options what is the scientific options what are technological options what is the scientist believe what the scientist think in fact they do not have to proceed it is that the government has to take steps into this okay with the IPCC simply just tell that what is happening and what is the scientific knowledge what the many scientists think so it is that the decision need to be taken by the different governments any other question sir good afternoon sir sir professor nigil has included that good print you know sir so when we are practicing means we can get a feedback of that and how can we regulate all the things and all say is it possible yeah we can do that and we can use that certainly this is exercise everyone of us should do but and try to reduce our emissions but then it is for example if I am using AC in my home 24 hours but reduce it they use just by 1 percent or 2 percent that would not be sufficient so that means it is not that means the major bigger question need to be answered also okay so certainly we can should use those calculations for prints and try to reduce it and everyone start doing it so cumulatively it will bring some results but they need to be taken major reforms for example how we produce energy etc okay so that certainly need to be done at higher level okay thank you very much sdm institute greenhouse gases like carbon dioxide that causes 60 percent greenhouse effect right sir yeah so go ahead go ahead ask complete question sir and what about other gases like methane nitrous oxide and water vapors so basically it's water vapors which is a major greenhouse gas it will be tricky to calculate it but they say that 50 to 60 percent of contribution even higher is from water vapors itself and then the second major one is carbon dioxide then I think methane NOx chlorofluorocarbon hydro chlorofluorocarbon so the major one to tackle is CO2 and the major one is water vapors but there is not much we can do with it okay so these are the few of major good afternoon sir sir regarding this global warming yeah you have mentioned that 94 percent of that particular causes of global warming is due to the active ogenic activity we are having one movie yeah name global warming swindle yeah which is against that particular thing can you justify that particular thing sir do we have any comment regarding that so in fact you know as I mentioned that there are 97 percent of the scientists which believe in global warming and there are 3 percent they are in the not agreement with the global warming and then they had made a movie like swindle and there are other research papers also coming on that but I personally believe that it is happening and they have enough evidences enough measurements telling it that global warming is happening across the globe we know that what is green house gas effect there is no denying about that there is also known that green house gases has increased its direct measurement because as I mentioned there always will be an uncertainty a small degree of uncertainty because it is almost very complicated to understand the earth as in itself a whole model okay so that kind of telling that this actually is leading directly it is almost difficult okay so because it is a very complex phenomena so there still are 3 percent or more or in that ring scientist which think that global warming is not happening but let me tell it in a very philosophical manner the philosophical manner is that what if I believe in it and then starting having wind starting using less resources for example coal for example natural gas what is the loss to me is there any loss or is there any gain I just start using clean technologies if you see if I replace coal by let us say solar wind etc they are actually are very much clean technologies right so is there any loss in doing that probably not so that is true that we should understand science and most of us has agreed that there is a science behind that but philosophically it is also good idea does to reduce use of energy use less energy go away from power plants for example coal power plants are leading even in addition to green house gas other kind of pollutants too right so that is a better idea actually having solar wind is very good idea so yeah so that kind of 3 percent is there so I think we have to stop here thank you very much