The history of GIS can be divided into four distinct phases. We will now examine each of these four phases in closer detail.

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1 This is the introductory section to the Geographic Information Systems (GIS) module. Although GIS and related Geo-technology can be a very technical subject, the purpose of this module is to present the origins, history, growth and uses of GIS in a non-technical manner as far as possible. We will also look at how the Internet has influenced the growth and uses of GIS, particularly focusing on visual display applications such as Google Earth. This module will discuss: The History of GIS Understanding GIS and its principles Understanding the definition of GIS Understanding the acronym G I S The Philosophy and Evolution of GIS The types of questions that GIS can answer What GIS is NOT The uses of GIS GIS and the Internet GIS and Google Earth How users define the nature of GIS 1

2 This module designed to provide non-gis practitioners and laymen specifically working in National Statistics Organizations in Africa with basic knowledge dealing with Geographic Information Systems, its principles, components, uses and successful implementation imperatives. It is therefore not intended as a technical reference and does not detail high level technical issues related to data models, spatial database design, spatial analysis and thematic mapping techniques and model building. The focus is on providing non technical individuals with basic knowledge to understand the core principles of GIS and related technologies such as Global Positioning Systems and Remote Sensing and how it can be relevant to the needs of their organization as well as the issues to take cognizance of when deciding to implement a GIS. 2

3 If you are reading this module, it means you are interested in GIS. You might be a manager at a National Statistical Organization (NSO) interested in how GIS can assist you in census planning and operations or this new agricultural or health survey you are planning. Whatever the case may be, the first thing you need to understand is What GIS Is and to do that, you need to know a bit about GIS history and where it comes from. The history of GIS barely spans four decades. It is difficult to pinpoint the origins of GIS as one thing, since the beginnings of GIS was driven by individuals and organization working in different areas. It is many things to many people. A demographer might view GIS differently from an environmentalist, since the statistical analysis methods used in the two subject matter fields and applied to GIS will vary. One thing that remains constant is that the growth in computing technology over the last four decades drove GIS development to such an extent that it is a widely used and accepted technology today. 3

4 Society has come to accept and indeed demand digital map processing in everything we do from getting driving directions from Google Maps to viewing the extent of the oil spill in the Gulf of Mexico on CNN. Since the 1960s, decision making processes have become increasingly complex, with mathematical and statistical models becoming commonplace. The computer age provided to us the means to handle large data sets and create effective spatial analysis processes. Spatial analysis is of course when we analyze data about people or the environment within the geographic context where it occurs. The prominence spatial information and GIS enjoy today was made possible by the advances in information technology. The history of GIS can be divided into four distinct phases. We will now examine each of these four phases in closer detail. 4

5 The beginnings of GIS can be traced to specific academics that wanted to automate map creation. In other words, in stead of creating a map on a piece of paper, they wanted to do it digitally on a computer. In stead of overlaying transparent map sheets on top of each other manually, they wanted to be able to overlay map themes digitally using a computer. GIS therefore had its beginnings firmly rooted in the quest to create and manipulate digital maps. Computer systems during the 60s and 70s were however limited to expensive mainframe systems and GIS development were therefore confined to universities and some government organizations who had access to these systems. Various individuals drove the quest for digital mapping simultaneously in North America and Europe. The pioneering work during this period established many of the underlying concepts and procedures of modern GIS technology. These were the early years of GIS. 5

6 During the 80s, the advances in information technology were exploited. New database and data management systems were developed that linked computer mapping capabilities with traditional database capabilities. (Think of combining the power of MS Access or Oracle with a map). It was therefore possible to link large volumes of attribute information, which is information about a real world feature, to the actual digital spatial feature itself and allowed for traditional database queries to be asked and answered in the geographic sense. Here, GIS began to distinguish itself by enabling spatial information to be queried in a way traditional database practitioners understood. During this period the demand for digitally mapped data increased and thereby focused attention on data availability, accuracy and standards. A new industry for digital map creation and data design emerged, as well as a market place to sell digital map products and the software that created them. 6

7 Practitioners in socio-economic development realised that information is a key driver for development, specifically spatial information. Users of statistical data was not satisfied with asking where things were, but were now asking why they were there and what their relation was to each other? By the mid 1980s, the focus moved to the analysis of traditional statistics within the spatial (geographic context). Users searched for new ways to analyze data using digital maps in order to create new information. It now became possible to apply traditional statistical and mathematical operations from different subjects (demography, environmental sciences, utility management, agriculture, geophysics etc.) to GIS. A whole new world of possibility opened up. Where previously statistical data was analyzed without the spatial component, the spatial statistical analysis within a GIS environment inherently implies that the spatial component is taken into account. The WHERE was now included in the analysis of statistical data. The new way of applying mathematic and statistical operations to spatial information allowed the GIS community to create new operations unique to GIS which in turn led to new GIS uses. It was now possible to determine the best route for an ambulance from point A to point B with the click of a button. It was possible for an investor to determine where the best location might be for his new fast food store by using spatial analysis and demographic techniques to determine optimum trade areas. 7

8 The fast growth of GIS from the 1960s established the underlying concepts, structures and tools supporting modern geotechnology. The term geotechnology encompasses GIS and all its related technologies, such as satellite imagery and Global Positioning Systems (GPS), but more about these later. What is radically different today is the broad adoption of GIS technology in our everyday lives. The days where spatial information was the province of spectacled university professors or well funded government defense departments are over. It is in our vehicles, our mobile phones, on TV and at work. Geography now truly matters to everyone. The US Department of Labour has designated Geotechnology as one of the three mega technologies of the 21st century, together with Nanotechnology and Biotechnology. Complex GIS software solutions are now giving way to web services and customized application solutions which are more user friendly. The role of web based spatial visualization tools such as Google Earth cannot be underestimated. These web based tools have extensive map layers that enable users to mix and match their own custom views. So, a person with no GIS background and who is totally oblivious of the complex database operations and command sequences that underlie these systems can use Google Earth to do route planning for his next vacation. Moreover, the full integration of GPS technology and remote sensing imagery with GIS further drives this phenomena. GPS and digital maps brings geographic positioning to the palm of your hand. Google Maps can be accessed via your mobile phone and you can view remote sensing imagery of the area of your choosing. The age of the neogeographer has arrived. A neogeographer is someone who uses geotechnology for personal or even business use but does not have a background in geography, GIS, GPS or remote sensing and might not even be that interested in these fields. It is the person who does route planning using Google Earth, the lady who uses the onboard navigation in her vehicle, the news reporter zooming in to a new news hotspot on television. GIS has therefore matured. Now, anyone with a browser can access geographic applications and use them sensibly. 8

9 The traditional definition of GIS is that it is a collection of hardware and software that allows us to create, store, analyze and disseminate spatial and its related attribute information. GIS operates on many levels. On the most basic level, GIS is used as a computerized mapping tool. However, the real power of GIS comes from using spatial analysis and statistical methods to analyze attribute and spatial information. The end result of the analysis is usually an answer to a specific question or new information. The main reason GIS exists today is that the information in a database can be linked to its associating spatial features. Here, the term database is a collection of information about features and their relationship to each other and georeferencing refers to the location of a feature on the surface of the Earth using a coordinate system. The fact that every object present on the Earth can be georeferenced affords GIS this ability. The ability to analyze statistics with digital maps and features distinguish GIS from other information systems and make it valuable to a wide range of public and private enterprises for explaining events, predicting outcomes and planning strategies. 9

10 The constant evolution of GIS means there are more to this acronym than meets the eye. Let s begin with the GI. It refers to the type of information GIS deals with, and can either mean Geographic or Geospatial. In fact, these two terms are often used interchangeably. Looking at the S, things become interesting. Considering how GIS has evolved, the S can mean any of the following: Systems: The software and hardware we use to acquire and manage geographic information, such as GIS and database software, GPS receivers and satellites and aerial photography cameras that capture remotely sensed imagery. Science: Understanding the science of representing spatial data, features and real world processes within a digital environment. Understanding the theory and use of GIS operations and processes. Studies: understanding the social, legal and ethical issues associated with the application of GIS, specifically regarding data security and individual privacy. Moreover, there are three distinct technologies that together form the basis for Geographic Information Technology as can be viewed in the slide. GPS and Remote Sensing are sources of input data for a GIS, while the GIS provides the means for storing, analyzing and manipulating GPS data and Remotely Sensed imagery data. We will look at this interrelationship in more detail later in this module. 10

11 Taking all of the above into account, Briggs has offered the following revised definition of GIS: A system of integrated computer-based tools for end-to-end processing (capture, storage, retrieval, analysis, display) of data using location on the earth s surface for interrelation in support of operations management, decision making, and science. This system includes a set of integrated tools for spatial analysis which encompasses end-to-end processing of data, uses explicit location on the earth s surface to relate data and is aimed at decision support, as well as on-going operations and scientific inquiry. So, GIS technology can be used to capture the location of features on the Earth as well as data about those features, store it in a database from which it can be retrieved and displayed on screen on a georeferenced map. This spatial and statistical data can be analysed with spatial analysis tools unique to the technology to create new information or provide answers to specific questions which can be used for decision making. Since the features are georeferenced to their locations on the Earth, it is also possible to investigate spatial relationships that these features or their attributes might have, which is not possible with traditional databases. 11

12 Why has GIS grown and evolved so much, and why is it important? It is in human nature to progress and in GIS terms we are constantly trying to progress from Data - which provides us the facts about ourselves, the features that surrounds us and the world we live in. For example, that over there is a well. To information which puts these facts into context. In GIS terms this can mean placing these facts and features within a spatial context, in other words, referencing them to their correct please on Earth using a coordinate system. For example, the well over there is next to the community centre and has the following latitude and longitude coordinates. To knowledge which searches for inter-relationships between facts. For example, the people in this village are suffering from cholera. If they are all getting their water from the same well, then it is reasonable to assume that the water of this well is contaminated with the ecoli bacteria that causes cholera. To wisdom which means understanding and knowledge upon which we can base decisions on and act upon. For example, we can now investigate the water source of the well and can determine that it comes from the nearby lake. Next to the lake is a sewage plant that leaks untreated sewage into the lake, which causes the spread of the ecoli bacteria. This is our knowledge. Our action is to repair the leak at the sewage plant and to provide the villagers using the contaminated well with water from another source until the contamination is under control and the ecoli levels are at an acceptable level. The key driver in GIS evolution is therefore to gain wisdom and understanding. Wisdom allows us to make accurate decisions using relevant knowledge. Modern GIS is therefore constantly striving to develop new database query, mathematical and statistical analysis operations and methods in order to distil spatial data and facts to information, knowledge and ultimately, wisdom. 12

13 OK, we have gone on and on about how wonderful GIS is, but what can you actually do with GIS? GIS is, essentially, an answer machine. You have a specific question you want to ask, so you add a bunch of spatial and attribute data, mix in some database queries, add some more spatial and statistical analysis operations, apply your own specialized knowledge of your subject matter field and viola, you have your answer. The key thing to remember is that the accuracy of the answer is dependent on the accuracy, currency and relevancy of the data used, the relevancy of the statistical and analysis operations used and of course, how accurately you applied your own knowledge to interpret the results. 13

14 Consider the following table, adapted from Berry. Typically, there are 7 basic questions that a GIS can answer, with of course many combinations of these 7 questions possible. The first three deal with data only, while the next four deal with the creation of new information, knowledge and ultimately, understanding. 14

15 The most basic question, "Can you map that?" is where GIS began forty years ago computerized mapping. Thinking back on the example of the well in the village, the question would be if we can map the location of this well within the village. Provided we have the coordinates of the well, the answer would be yes. A large proportion of GIS applications still involve the updating and timely output of map products. The city and country road maps that you buy at the book shop is a case in point. Considering this question in a census environment, for example, a typical question would be: Can we map our new Enumerator Area boundaries digitally and can we add prominent landmarks as points within each EA polygon? 15

16 Questions involving "Where is what?" exploit the linkage between the digital map and the database. The manager of a courier company might want to plot the physical location of their customers on a map in order for their drivers to find customers addresses easier. Using the address list of the customers, GIS can plot the locations of customers on existing road and street data as points. The question Where is What therefore becomes Where is my customers?. Let us use the example of the well again. Remember we asked what water source the well utilizes, thus, Where is the water source for the well?. Again, in a statistical organization, a relevant question might be: Where are the Enumerator Areas with a male population of more than 200?. 16

17 The third type of question, "Where has it changed?" involves time. These questions mark the transition from data to information queries. A graphic portrayal of changes in geographic space, whether employment figures per region over a 10 year period or changes in population density and migration patterns over time, affords a new perspective on existing data. A typical question in a statistics environment might be to assess the prevalence of pit latrines within a peri-urban environment over a period of five years. 17

18 "What relationships exist?" questions play heavily on GIS analytic operations. "Where are populated areas not covered by VCT clinics?", "Can this school be accessed by road from this village?", "How far is this village from the cholera contaminated river?", and "Is the population more dense over here than over there?" are a few examples of this type of question. Whereas the earlier types involved query and repackaging of base data, spatial relationship questions involve derived information. If users are unaware of the different things a GIS can do differently, chances are they are not going to ask it to do anything different. Considerable training and education in spatial reasoning approaches are needed to fully develop GIS solutions to these questions. In the example in the slide, we can see how GIS is used to determine a relationship between female literacy and contraceptive use. Going back to our example of the well, we investigated the relationship between the well water and the occurrence of cholera in the village. 18

19 Suitability models spring from questions of "Where is it best?, in other words, which areas are most suitable for a specific purpose? Possible questions to ask within a NSO environment might be Where is the best location for the new primary health clinic in this region? or Which villages has the highest concentration of Orphan and Vulnerable Children to be targeted by feeding schemes? Spatial reasoning capability and relevant subject matter knowledge are important in order to formulate your question of Where is best properly in order to obtain the maximum benefit from your GIS. Again, with the well example, we might have wanted to know where is the best area to build a new well that will minimize the possibility of being contaminated with ecoli. We would have taken into account the location of the water table, the source of water for the new well, the distance of the new well from the villagers and the possibility that the water source for the well might be contaminated by raw sewage before we would make the decision. 19

20 "What effects what?" questions involve the building of models to determine certain outcomes. These are therefore outcome based models built with the sole purpose to identify causality or trends within real world environments. 20

21 A suitable example within a health context might be to model the prevalence of mosquito pupae per person in order to determine the future spread of Dengue fever or to model the prevalence of HIV/Aids along major overland truck transport routes in order to determine causality. Going back to our well example, we might want to ask how the rest of the village will be affected if all the other wells in the village also become contaminated, in other words, how will the cholera outbreak spread among the villagers? Provided the relevant information has been gathered, a model can be built using GIS to answer the question. The graphic in the slide depicts how geocoding can be used to connect customer addresses to their geographic locations for subsequent map analysis, such as generating a map surface of customer density. The density analysis can then be used to determine which factors causes certain areas to provide more customers than others. 21

22 "What if...?" questions models and predicts outcomes of real world actions and occurrences which already happened or might still happen. Scenario planning relies heavily on outcome or forecast prediction. Typical questions might be, If we build this dam over there, which villages would be in danger of flooding and would need relocation or If the undersea oil well leak in the Gulf of Mexico remains uncapped for another two weeks, at the rate of current leakage, which coastal areas might be affected?. 22