 Welcome to this fourth lecture on the first chapter of introduction and so this is the last lecture of this chapter and in this lecture we will be focusing on the various literature sources, the data sources as well as internet sources which are related to ground water. Now, let us come to the various sources as you all know. So, this ground water it forms one of the major component of fresh water. So, therefore, right from the beginning of the human society there have been attempts to estimate or document or even present. So, the various phenomena related to ground water and it is always this ground water is in combination with surface water. So, therefore, so there have been various right from the human the beginning of the human history. So, there have been attempts and many of them are even now. So, they are existing and let us come to first let us come to this the various literature that are available in this on ground water. Firstly it is the I would like to start with the oldest ones chronologically it is the ancient books and other traditional knowledge sources. So, these are essentially in all the regions where the human civilization started. Say for example, all the river valley civilizations whether it is the Indus valley Indus river valley civilization in the present India and Pakistan or whether it is the Mesopotamian river valley civilization in Iraq or it is the Nile river valley civilization in Egypt. So, wherever this river valley civilization started. So, along with that so, there the documentation of the ground water related phenomena as well as the ground water related structures and all those things started. So, here we can mention. So, in the Indian context we can mention the Brahat Samhita written by Varaham Hira actually and of course, the original Sanskrit text it has been translated and many commentaries have been written because and here. So, because the property of Sanskrit language in which maximum meaning is conveyed in minimum letters words and sentences. So, there is a lot of room for interpretation. So, many interpretations have also been written and coming to this and also another example I can give is the Saraswathi river in the India which was earlier it is believed to be a tributary of Indus and presently it is believed to be a it is a tributary that is an unseen tributary of river Ganga joining as a third that is underground stream along with Yamuna in the city of Alhava. So, here so, this and there have been the problem with these traditional as well as ancient sources is many of them are under documented or undocumented, but still there are many proofs say for example, the entire Rajasthan in the entire state of Rajasthan. So, the present they in the middle of Rajasthan. So, there is what is presently known as Ghargarh river as one catchment. So, there is an ample groundwater reserve available and even now so, there have been many studies by few studies by the space application centre Amdabad of Indian space research organization. So, they had they are trying to bridge the gap between this undocumented or under documented ancient sources and I am sure there is a same case with whether it is the Mesopotamian river valley civilization in the present day Iraq or the Nile river valley civilization in the present day Egypt or even other the Chinese ancient river valley civilizations or even the other as one like the Israel and so on. So, now, let us come to the other sources other than this ancient books and traditional as one. So, it is the books and hand books and there have been many books and hand books on groundwater written almost in the past say 150 to 200 years either as a part of the water resources or hydrology or hydraulics books or exclusively as a part of groundwater. And also there have been many hand books which contain not necessarily on groundwater other phenomena such as hand book of hydrology, the hand book of hydraulics or hand book of say water resources and all this. So, they also constitute a very large amount of literature and so on. Next is it is the journal publications and it has been mentioned that in the past 150 years or so. So, there have been many journals related to hydrology, hydraulics or water resources groundwater and so in these journals or water resources economics in these journals more than say 55,000 of 55,000 articles they may be full length papers or they may be discussions or they may be other case studies. So, they have been published and it constitutes even a large source of literature. And now let us come to the other publications which is the conference publications and it has been in the past say 100 years or so a large number of conferences have been organized on water related issues on hydrology and hydraulics and water resources economics groundwater. And so these publications conducted by organized by various national as well as international bodies. So, they also present a large source of literature. Next it comes to the publications from the United Nations affiliated bodies. So, here so there is what is called the UN water which consists of say 28 United Nations bodies and out of them the 3 important ones I would like to list here which is the UNESCO United Nations economics this educational I am sorry educational scientific cultural organization headquartered in Paris France the World Meteorological Organization WMO the food and agricultural organization that is in headquarters in headquartered in Rome Italy. So, these are some of the 3 or 3 main UN organizations in the which constitutes a 28 United Nations bodies constituting collectively what is known as UN water. Also next it is the publications from government agencies and in this case the governments depending upon their technical capabilities in the developed countries such as USA or many European countries at Japan the former Soviet Union the present Russia as well as the council of independent states as well as the ground water board central ground water board in India. So, these so their publications so they may be in the form of handouts or they may be in the form of books or they may be in the form of say maps or they may be in the form of tables or charts or predictions. So, all these they also constitute an important form of literature pertaining to ground water. Next let me list here the publications from non-governmental organizations as well as agencies in addition to the governmental organizations. So, there have been many non-governmental organizations involved in the water sector. So, they have brought out their own publications they may be again books or they may be guidelines or they may be other resources for conserving other handouts or manuals to conserve ground water to conserve surface water in conjunction with ground water and in this I would like to mention. So, in the Indian context I would like to mention the centre for science and environment in New Delhi as well as the Gandhi peace foundation. So, as well as the so there are many other bodies which work in the area of water. So, their publications their books handouts their other maps and so these are also various and coming to next is the publications by corporate organizations and their collaborators. So, here I would like to mention the publications brought out by this World Bank, Asian Development Bank as well as other financial institutes or corporate bodies which are involved in this funding various projects related to water resources, ground water, hydrology, hydraulics and so on. So, they also form a very important source of ground water and lastly I would like to mention here all other sources even a simple this newspaper article pertaining to say ground water or ground water in conjunction with surface water and other so the magazine articles as well as the popular science articles and as well as the popular TV programs such as on the Discovery Channel the programs which are aired on the Discovery Channel and other such educational TV programs. So, they also form a very important source of literature pertaining to ground water and in the this and added to this is the recent impact of climate change and so which has resulted in the constitution of bodies such as the intergovernmental panel on climate change. So, they also they have brought out many publications case study scenarios future case study scenarios. So, all these form an important sources of literature available on the ground water. So, and as we all we should be aware that the these literature pertain to the ground water which is below the surface of earth and obviously, so the as I am reminding right from lecture one. So, there are more in so ground water represents the invisible or say less visible domain of water resources. So, there is more room for uncertainty and then more room for say error and there is more room for speculation and all this. So, therefore, all these literature which is available which I have mentioned here should be taken with a pinch of salt of course, they have to be verified. So, their authenticity, their applicability as well as their usefulness need to be verified using the basic principles of science, engineering and technology and so we should always bear in mind that so these ground water resources the literature on ground water. So, it should be relevant, it should give the useful information and it should also be willing to stand the test of time in the limited time horizon at least. Now, let us come to the various data sources which are available on ground water. So, in this as I mentioned in the literature which I was mentioning few minutes back. So, in all these literature so there is there are large amount of data sources which is available in the form of say graphs, maps as well as tables and nomograms and other and here. So, in this case so there we should also I would also like to mention here some of the traditional knowledge basis which may be under documented or under documented. Say for example, in the Indian context. So, there is a popular belief that the water from Ganga in the north is going to join the waters from the South Indian rivers or the rivers in the other regions of India such as in the west and as well as in the south. So, of course there is a need to scientifically verify these kinds of popular beliefs, but at the same time. So, there is no harm in studying in initiating studies which there is a possibility if that they may solve they may provide to be a good source of data for addressing the quality as well as quantity issues in ground water. So, here coming to the data sources the data presented in books the data presented in hand books as I mentioned. So, there are various hand books which are published on ground water or hydrology, hydraulics as well as the data presented in journal and here we should also remember that data does not essentially mean the numerical data. It may also include the data presented in the form of graphs, in the form of charts or in the form of maps in addition to the statistical or numerical data as well as the data published in the presented and published in the conference publications or say symposia or seminar and all these. So, they constitute the major sources of data available on ground water. First it is the data presented or data which is available from the UN affiliated bodies as I was mentioning it is the UN water consisting of say 28 UN bodies out of them. So, few that is I have already mentioned about say UNESCO, the World Meteorological Organization, the Food and Agricultural Organization. You may wonder why this Food and Agricultural Organization is also such a major reason because so water goes hand in hand with food and for growing food. So, there are the water is a major requirement and so therefore, the food and agriculture represents the major consumer of water resources. So, therefore, food and agriculture organization, so they have evolved their own methods for estimating the water which is available at present as well as estimating water in the immediate future. So, therefore, and added to that, so there are say the UNESCO, it has a special portal on water and in this UNESCO water portal, so the discharges of the various rivers, the maximum discharge, the minimum discharge, the annual maximum discharge, the annual minimum discharge as well as the monthly average discharge for all the rivers in the world. So, they have been presented in tabular form and so they include the largest river in the world in terms of discharge that is the Amazon river in South American continent which is the most water rich continent in the world as well as the rivers which are flowing through the deserts in Africa or in say few rivers such as the Nile river and so they have been also presented in this UNESCO, the discharges of selected rivers and so there are other data like such as the world water assessment program, the international hydrology program that is IHP, the world water assessment program that is WWAP, the global water partnership which is the partnership between UN bodies such as World Meteorological Organization, UNESCO as well as other world food and agricultural organization. So, all this, so they constitute, they have presented the data related to groundwater in general as well as groundwater and surface water in ground water in particular, ground water and surface water in general in the form of various maps, charts, numerical or statistical data as well as graphs and so they constitute some of the major ones and here I would like, I would also like to mention the intergovernmental panel on climate change and coming to the other data that is available. So, here I would like to mention the data which has been published by the various government agencies say like in the Indian context, the Ministry of Water Resources, so they have published the data pertaining to the nonclassified rivers. Unfortunately, so the Indian government is always associated with water conflicts with neighbors earlier it was Bangladesh and presently it is also with Pakistan in terms of this one. So, therefore, for the nonclassified rivers of India, so the data pertaining to groundwater as well as groundwater and surface water is published in what is known as the integrated hydrological data book which can be easily purchased or even it can be downloaded as one and in case of US it is USGS database. So, this USGS database, so it is one of the very extensive database which pertains to the rainfall or precipitation as well as it pertains to runoff. So, here in terms of this rainfall, so all the 58 contiguous states of US main land, so they have been divided into say various meteorological zones and as well as smaller regions. So, depending upon the altitude of a region, the distance from the coast as well as other features, so this USGS database pertaining to precipitation as well as the USGS database pertaining to the runoff. So, in which all the rivers have been classified into the different basins and each river has been given an 8 digit code the first 2 digits representing the basin, the third and fourth digit representing the sub basin, the fifth and sixth digit representing the mini basin or the small basin and the seventh and eighth digit representing the micro basin or the smallest basin which is also known as hydrologic unit. So, like this every river tributary has been given a numerical code and then accordingly, so its data has been the data pertaining to the surface water as well as surface water and ground water in that basin has been presented. In the Indian context, it is the CWC database in India which consists of the various gaging stations. So, these gaging stations have been divided into the gaging stations which provide the data on simply gage as well as discharge which is essentially surface water data and there are few gaging stations which also provide data in terms of gage discharge then sedimentation and water quality as well as the NRSA the national remote sensing agency maps published in India. So, like that, so there have been other the data maintained and published by the river basin authorities such as the Bhakra Bias Management Board, the Brahmaputra Board as well as the other the Narmada control authority or in case of say USA, it is the St. John's water district in Florida and so even in many other European as well as the Asian agencies, there have been many agencies which maintain the data related to river basin and obviously, they also maintain the ground water related data in that particular basin and added to in addition to this, so the data maintained by state and local government agencies some of the state as well as local government agencies in developing countries such as India, the developed countries such as USA as well as Europe, Japan and other countries. So, they have maintained a very good data again in the form of say statistical data graphs, maps, charts and all these. So, depending upon this one, they have a very good monitoring network and so their data is also one of the next is the data from say non-governmental organizations or agencies. So, in this case in the Indian context, I would like to mention the citizens report brought out by the Center for Science and Environment. So, so far they have brought out the data book on the 5 citizens report on environment in the state of the environment especially the 5th citizens report which contains one source which is essentially the statistical data pertaining to say other environmental related issues which in which water in general and ground water is also very important. So, and of course, there are other non-governmental agencies working in the water sector. So, they have also brought out many they have also published collected and published data from their various studies and next it is the data from the corporate or corporate organizations and their water bodies. So, here I would like to mention the World Bank, the Asian Development Bank as well as other funding agencies which have funded various water resources as well as ground water related programs. So, the surface water and ground water interaction and all these so the data published from these also constitute and next is the data from other sources. So, here in this case the data from other sources it could be even say simple school text book or it could be from a TV program, the popular science program or it could be from any other sources such as a newspaper article or it could be even from this popular science fiction books or so they also have presented a large amount of data pertaining to ground water. So, these are some of the data sources which are available in this ground water and now let us come to the last part related to the ground water data which is the internet data source as it is evident now. So, the internet forms a large amount of data source which is essentially it is an online library. So, earlier there used to be the actual libraries wherein the data in the form of say books or even say other databases. So, it was physically stored and it was being accessed by various so on. These days it is the internet which is the basically the information super highway. So, in this there is a large amount of data source and here I would like to mention the online libraries, the online databases maintained by the publishing the journal publishing houses as well as various professional organizations, their websites, online libraries, databases and so on. So, here so it is the this is a vast source and this most of the data which has been which is available in the either as a literature or as a data source is also available in these days as a source on internet and of course, due to their commercial one. So, it may not be available fully, but at least a significant amount of that is available in the form of data source. Here in the journal publishing houses I would like to mention here say few of the two of the most important journals related to ground water that is the ground water journal as well as the journal of hydrology. So, these journals so they have the ground water journal so they maintains a large amount of database and online library. So, which can be accessed by doing a simple internet search and so it contains the information about the books, the journal articles, the databases as well as other sources and so on. So, which is very much useful especially in the areas especially in places where we may not find the physical sources of ground water related literature or data. And also the UN agencies so they have also maintained and they are maintaining the online libraries as well as databases I was mentioning the UN water consisting of say 28 United Nations bodies or agencies. And in this case the recent the IPCC publications, the intergovernmental panel on climate change, the world water forum, its data, the stock home water and other so on. So, these also constitute a vast amount of internet sources. Next is the online libraries, the databases of government agencies some of the government agencies especially in the US and other developed countries. So, they maintain a large amount of database on the studies and so here I would like to mention the USGS real time database in which we can get the data pertaining to the discharge of this in the river in the surface water bodies such as rivers as well as the water table data in the observation networks in the these data stations or gauging stations. And so there is here I would like to mention also about this what store it is the national water data storage and retrieval system of USA like that. So, there are other online databases libraries which constitute a large amount of data which is available online. So, coming to this the internet as well as the data sources and in the Indian context it is the here the national centre for medium range forecasting weather forecasting. So, this is a centre pertaining to so on. So, here it the weather forecasting is done and based on this weather. So, depending upon the that is the ground water abstraction making suitable assumptions in the surface water so on. So, there is a possibility there is a there is a very good chance that we can do a reasonable estimate of the ground water availability the depth of ground water and as well as other as one. So, and there are other there are also other agency say like in India there is what is called the national institute of ocean technology N I O T in Chennai. So, they have done a very useful study on this desalination of sea water. So, as to provide fresh water and they have done a very good study on the fresh water sea water interface. And so, it provides a very good this one because it is mentioned that. So, this in spite of all the studies on this all the studies as well as literature as well as data which is available on ground water which constitutes a major source of fresh water. So, still there is a need that because of the adverse impacts of climate change and global warming. So, the water resources the fresh water resources are getting depleted quantitatively as well as they are getting polluted qualitatively. So, therefore, so this the study on this fresh water sea water interface as well as the study on desalination and using and generating fresh water which obviously which is being done in nature in the form of hydrologic cycle. So, through evaporation and then so the storage of the atmospheric moisture which has evaporated from the surface water bodies into the clouds and then subsequent condensation and precipitation. So, here so this desalination represents the artificial way of this one that is the artificial replication of the natural hydrologic cycle or water cycle. So, and also it is said that in the world. So, more than say 50 percent of the global population it is estimate the exact estimate is around say 60 percent of the global population lives in a region close to the coast which is within say 100 kilometers of the coast. So, therefore, so there have been attempts in the Middle East as well as in India, in say USA as well as other regions on the this that is the desalination aspect as well as producing fresh water. So, they it also represents large amount of data pertaining to this one and added to that. So, there have been say the artificial say this is the groundwater recharge guidelines, guidelines for water harvesting say guidelines for say groundwater pollution mitigation etcetera. So, such guidelines have been published by various government agencies as well as various non-governmental agencies and other professional the organizations. So, these guidelines so they are based on the case studies which are existing which are pertaining to groundwater and so these also present a large amount of very useful information as to how to address the issues of the groundwater decrease in quantity as well as quality. And also there have been other sources on groundwater and many times. So, there are many undocumented or under documented this literature pertaining to groundwater and many experts on groundwater. So, they have formed their own networks and they have formed their own sources of literature or data and many of these sources and literature. So, they are also available the online and this one. So, these form some additional sources of groundwater. So, essentially so our objective this in this through this chapter 1 which is on introduction in this we discussed about the background the we discussed about the historical background. We discussed about the groundwater utilization we discussed about the ground water its position or its status in the hydrologic cycle. We also discussed the ground water budget which is based on the mass conservation principles. We discussed the ground water level fluctuations and the environmental influence and lastly we discussed about the various literature data as well as internet sources or resources which are available related to ground water. So, this completes the first chapter on introduction and in the next chapter we will discuss on the occurrence as well as moment of ground water. So, thank you and so we will in the next the second chapter the next lecture will be on the second chapter on say ground water occurrence and movement. Thanks you. Thank you. Bye.