Assignment Code: BGGCT-133/TMA/2023

Course Code: BGGCT-133

Assignment Name: General Cartography

Year: 2023

Verification Status: Verified by Professor

Part-A

All Questions are compulsory and carries 10 marks each.

1. Describe the history and evolution of cartography.

Ans) Cartography, the science of making maps, has a rich history that spans thousands of years. Over time, the development of cartography has been influenced by a range of factors, including technological advancements, cultural exchange, and the changing needs of society.

The Ancient Period: The Egyptians, Greeks, and Romans are among the ancient civilizations that are credited with the invention of cartography. These societies constructed rudimentary maps for use in their military endeavours, religious practises, and commercial endeavours. For instance, the ancient Egyptians drew maps of their land to assist them in navigating the Nile River and in defending their boundaries against incursions from neighbouring nations. On the other hand, the ancient Greeks relied on maps to guide them through the sea and into uncharted lands as they expanded their empire. Their maps were frequently accompanied by in-depth narratives that elaborated on the locations that they mapped.

The Medieval Period: The practise of mapping continued to advance throughout the Middle Ages, particularly in Islamic and Chinese cultural contexts. Using methods like as triangulation and the use of stars to establish location, Muslim scholars created some of the most extensive and precise maps that were available at the time. During this time period in China, maps were used to describe the enormous expanses of the country as well as to assist visitors in navigating the complicated route networks. The "Da Ming Hunyi Tu" is a map that was constructed in China in 1389 and portrays the entire world as it was known at the time. It is considered to be one of the most famous maps from this time period.

The Modern Period: A new stage in the evolution of cartography began with the invention of printing at the same time as the Age of Exploration. Sailors were assisted in navigating the world's waters and charting new regions with the assistance of maps that got more accurate and detailed over time. A Flemish cartographer named Gerardus Mercator came up with a novel method of map projection in the 16th century that made it possible to navigate over great distances with high degrees of accuracy. Throughout the 19th and 20th centuries, technological advancements in surveying, photogrammetry, and remote sensing contributed to additional improvements in the precision and level of detail of maps.

Today, cartography continues to evolve as new technologies, such as Geographic Information Systems (GIS), are developed. With the ability to create highly detailed, interactive maps that can be updated in real-time, the role of cartography in modern society has expanded beyond traditional navigation and exploration, and into fields such as urban planning, environmental management, and disaster response.

2. What is Pushbroom scanning? Elaborate Pushbroom Cameras data.

Ans) Pushbroom scanning is a method of collecting remote sensing data using a type of camera known as a pushbroom camera. The camera consists of a linear array of sensors that scans the ground below as the camera moves along a path. The sensors capture data on each point as it passes, allowing for rapid data acquisition over large areas. The resulting data can be processed and used to create high-resolution images and maps for various applications, including remote sensing, satellite imaging, and environmental monitoring. Pushbroom scanning is particularly useful for mapping large areas or monitoring changes in land use or vegetation over time.

Pushbroom Cameras Data

Pushbroom cameras are commonly used in remote sensing applications to collect high-resolution data over large areas. Unlike traditional frame cameras, which capture images one frame at a time, pushbroom cameras use a linear array of sensors to capture data continuously as the camera moves along a path. The resulting data can be used to create detailed images and maps for various applications, including environmental monitoring, satellite imaging, and geological surveying.

The linear array of sensors in a pushbroom camera is typically made up of thousands of individual sensors, each of which captures data on a single point as the camera moves along its path. The sensors are arranged in a single line and are oriented perpendicular to the direction of travel. As the camera moves, each sensor captures data on a different point on the ground below, and the data is combined to create a continuous image of the area.

One advantage of pushbroom cameras is their ability to capture data quickly and efficiently over large areas. Because the camera collects data continuously as it moves along its path, it can cover a wide area in a short amount of time. This makes pushbroom cameras ideal for mapping applications, such as creating topographic maps or monitoring changes in land use over time.

Pushbroom cameras also provide very high-resolution data. Because each sensor captures data on a single point as the camera moves along, the resulting image can be extremely detailed. This allows for precise measurements and analysis of the data, making pushbroom cameras particularly useful in geological surveying and environmental monitoring.

Overall, pushbroom cameras are a powerful tool for collecting remote sensing data. They allow for rapid data acquisition over large areas and provide high-resolution data that can be used for a variety of applications, including mapping, environmental monitoring, and geological surveying.

3. What are weather elements? Explain any four of them.

Ans) The various components that come together to form the weather and give it its features are referred to as the weather's elements. There are a number of components that make up the weather, some of which are temperature, humidity, air pressure, wind speed, and precipitation, amongst others. The following are the four types of weather elements:

Temperature: The degree to which the air is either warm or cool is referred to as its temperature. A thermometer is typically utilised to determine if it is in degrees Celsius or Fahrenheit. Temperature is an essential component of meteorology since it has a role in the development of numerous weather phenomena, including cloud formation, precipitation, and atmospheric pressure. Low temperatures can lead to frostbite and hypothermia, while high temperatures can raise the risk of heat-related illnesses and wildfires. Low temperatures can also cause heat stroke.

Humidity: The amount of water vapour that is present in the air is referred to as the humidity. The proportion of water vapour that is actually present in the air as compared to the maximum quantity of water vapour that might be present at that temperature is typically how it is measured. Relative humidity is the term used to describe this measurement. The air may feel hotter and more uncomfortable when there is a high humidity, whereas there may be problems with dry skin, eyes, and respiratory function when there is a low humidity.

Air Pressure: Air pressure refers to the force exerted by the weight of the atmosphere on the earth's surface. It is usually measured in millibars or inches of mercury using a barometer. Air pressure affects the movement of air masses and is responsible for the formation of high and low-pressure systems, which in turn affect the weather. Low-pressure systems are typically associated with cloudy, rainy weather, while high-pressure systems usually bring clear, sunny weather.

Wind Speed: Wind speed refers to the rate at which air moves across the earth's surface. It is usually measured in miles per hour or kilometres per hour using an anemometer. Wind speed is an important weather element as it affects the way heat and moisture are distributed throughout the atmosphere. Strong winds can cause damage to structures, power lines, and trees, while weak winds can lead to stagnant air and poor air quality. Wind direction is also an important weather element, as it can determine the source and movement of air masses.

4. Explain the seasonal characteristics of Indian weather and highlight the importance of weather forecasting.

Ans) The monsoon winds bring rain to India between the months of June and September each year, and these winds have a significant impact on the country's climate. The monsoon season is the most notable aspect of India's climate, and it has a huge influence on the country's agricultural sector, as well as its economic and social structure.

The following is a list of the seasonal characteristics of the weather in India:

1. Winter (December-February): The majority of India experiences a weather pattern that is defined by chilly temperatures and dry conditions during the winter season. Temperatures in the northern portions of India can drop below freezing, and snowfall is a possibility in some of these places.

2. Summer (March-May): The majority of India experiences temperatures during the summer months that range from 35 to 45 degrees Celsius and are characterised by high levels of humidity. The levels of humidity are not exceptionally high at this time of year, which is one of the reasons why.

3. Monsoon (June-September): The monsoon season is characterised by prolonged periods of heavy rainfall across most of India. Rainfall is brought to the western coast of India by the winds of the southwest monsoon, and it eventually moves inland to other regions of the country. Rainfall is required for the majority of India's crop production; hence the monsoon season is extremely important for agriculture.

4. Post-monsoon (October-November): The post-monsoon season can be identified by the absence of cloud cover and the generally cooler temperatures that prevail during this time. Because to the winds brought by the northeast monsoon during this time of year, precipitation can be found in the southern areas of India.

Because of the varied climates that can be found across India and the key role that agriculture plays in the country's economy, accurate weather forecasting is crucial there. Accurate weather forecasts can assist farmers in planning their crop cycles, minimising the risk of crop loss caused by extreme weather events, and ensuring the continued availability of food. In addition, precise weather forecasts can assist the government in preparing for natural catastrophes like floods, cyclones, and droughts, all of which have the potential to have a substantial influence on the economy and society of the nation. In general, accurate weather forecasting is essential for the continued economic growth of India as well as the health and happiness of its people.

Part-B

All Questions are compulsory and carries 10 marks each.

5. Define map projection? What are its properties? Explain.

Ans) A map projection is a method of representing the three-dimensional surface of the Earth onto a two-dimensional surface. This process involves the transformation of coordinates from the Earth's curved surface to a flat surface, such as a map or a computer screen. Map projections are used to create maps that can be used for navigation, geographic analysis, scientific research, and other purposes.

Map projections have several important properties, which can impact the accuracy and usefulness of maps. Here are some of the main properties of map projection:

Shape: A shape-preserving projection, also known as a conformal projection, preserves the shapes of objects on the Earth's surface. This means that the angles between lines are preserved, so that circles on the Earth's surface remain circles on the map. This is important for preserving the accuracy of shapes, such as the shape of a country or the outline of a coastline.

Area: An equal-area projection, also known as an equivalent projection, preserves the relative sizes of areas on the Earth's surface. This means that the area of objects on the map is proportional to their area on the Earth's surface. This is important for preserving the accuracy of area measurements, such as the area of a country or the amount of forest cover in a region.

Distance: A true-distance projection, also known as an equidistant projection, preserves the distances between points on the Earth's surface. This means that the distance between any two points on the map is proportional to their distance on the Earth's surface. This is important for preserving the accuracy of distance measurements, such as the distance between two cities or the length of a road.

Direction: A true-direction projection, also known as an azimuthal projection, preserves the direction or bearing from one point to another. This means that the angle between two lines on the map is proportional to the angle between them on the Earth's surface. This is important for preserving the accuracy of directional information, such as the bearing from a ship to a lighthouse or the orientation of mountain ranges.

Different map projections have different combinations of these properties, and the choice of projection depends on the intended use of the map. For example, a shape-preserving projection may be used for a map of a city, while an equal-area projection may be used for a map of a country or region.

One common problem with map projections is distortion. Because the Earth is a three-dimensional object and maps are two-dimensional, it is impossible to create a map projection that accurately preserves all four properties of shape, area, distance, and direction. As a result, most map projections involve some degree of distortion in one or more of these properties. For example, a shape-preserving projection may distort the sizes of areas, while an equal-area projection may distort the shapes of objects.

6. How do you represent relief by contours? Give examples with neat sketch.

Ans) Maps display relief using hachures, form lines, layer colouring, hill shading, contours, spot heights/benchmarks, and triangulation stations. Fine broken lines along the maximum slope are hachures. In 1799, Austrian army commander Lehman proposed a terrain flow line sign. Steep slopes have dense hachures and are close together, but mild slopes are wider. Flat sections are blank. These show relief but not height.

Form lines break contour lines. These are surveyor estimates without direct measurements of the region. Mountainous topography makes surveying some regions difficult. Toposheets show ground height using spot height, benchmark, and triangulation stations. Spot heights represent land surface height above mean sea level. The toposheet shows it as a dot symbol with numeric heights in metres or feet. Benchmarks accurately measure the height of significant objects like buildings, pillars, bridges, and rocks. The toposheet shows the point's elevation as BM followed by numbers. Triangulation stations, unlike spot heights, show the height of a triangulation pillar on the ground. Triangle symbol and number on toposheet. A plate on the ground marks the trigonometric points, making them more accurate in location and height.

Topographical maps show relief best with contouring. Contours are isarithms connecting elevation points. Dutchman Cruquins invented line symbol in 1730. Contours are visual lines that link places of similar elevation on the ground above or below a reference surface like mean sea level. Map contours cannot merge or cross except on vertical surfaces like cliffs, caves, or walls. The contour height is printed on the toposheet contour line. The index contour—every fifth or tenth contour line—is thicker than the others and labelled to help us determine heights (e.g., 100, 200, etc.). Contour interval is vertical distance between contour lines. Map scale, relief, and purpose determine contour interval.

One can quickly gain an understanding of the shape of the land surface by referring to the contour pattern. The significant distance between contour lines is one factor that contributes to the steepness of the land surface. When contour lines are close to one another, it means that the slope is steep; on the other hand, when the slope is mild, it means that the contour lines are far apart from one another. Give us some examples of surface features and explain how those features are reflected in the contour patterns. By viewing the accompanying diagrams, you will have a better understanding of these surface aspects.

7. What are general rules followed for the representation of data through diagrams?

Ans) Some of the most important rules for how data is shown are:

Selection of an Appropriate Method: This is the first and most important thing we think about when showing geographical data. As you know, geographical data comes from many different places and covers many different topics, such as weather, population growth, production, distribution, and trade of different goods, etc. These aspects of the data need to be shown in the right way using the right kind of graph. For example, line graphs may be the best way to show data about changes in temperature or population growth over time and between different countries or states. In the same way, bar diagrams work best for showing things like rainfall or the production of goods. There are some kinds of information that are best shown with both line and bar diagrams. The information shown in this diagram is about the temperature and amount of rain in a certain place.

Selection of Suitable Scale: Once we've decided how to represent geographical data, the next step is to choose a good scale for measuring data. The scale is used to measure the information that will be put on a map or diagram on a piece of paper. So, choosing the right scale for the given data sets should be done carefully and should take into account all of the data. You should try to find a scale that is neither too big nor too small.

Appropriate Design: We all know that design is a big part of cartography. It refers to the way a diagram is set up and the things that go with it. It has a title, an explanation, and a scale. In the case of a map, direction is another thing that is taken into account. Let's talk about each of these parts of design in turn.

1. Title: The name of the area, the year of the data used, and the main idea of the diagram are all shown in the title. These parts are shown by words and numbers on the paper that have different font sizes and thicknesses. Usually, the title, subtitle, and year are written in the middle of the top of the map or diagram. We can't call this a rule, but it is how things are done.

2. Legend or Index: Another important part of a diagram is this. It explains the diagram's colours, shades, symbols, and signs. It must match what is shown in the diagram. Even though there are no hard and fast rules about where the legend or index goes, it is usually at the bottom left or bottom right of a map or diagram.

3. Scale: Like legend, there are no hard and fast rules about where to put a scale. So that the presentation looks even, it is placed just below the legend, on the opposite side of the sheet, if there is room. For instance, if the legend is on the lower right side of the sheet, the scale is on the lower left side, and vice versa.

Part-C

8) Write Short notes on the following. Each question carries 5 marks.

a) Graticule

Ans) A grid can also be used to define a location on a map instead of using coordinates. A grid is a network of horizontal and vertical lines that are evenly spaced apart from one another. By selecting the reference grid for a map, it is possible to generate it with the given number of rows and columns. On maps, measured locations can also be displayed by utilising grids in conjunction with projected coordinates. Graticules, on the other hand, are a network of lines that can be either horizontal or vertical and indicate the parallels of latitude and meridians of longitude, respectively, for the world. The specific application of graticules is that geographic coordinates, such as degrees of latitude and longitude, can be used to demonstrate where on earth one is standing.

Assuming that the earth is a sphere, the essential characteristics of graticules are:

1. Because of the flattening at the poles, the equatorial circumference is not the same as the meridional circumference.

2. Along the meridian, the length of a degree does not stay the same, and the length of the meridian is equal to half the circumference or half the length of the equator.

3. In the same hemisphere, no parallel is the same length as any other parallel.

4. Along a given parallel, the space between meridians is always the same.

5. As you move toward the poles, the space between meridians gets smaller, and the length of all parallels gets shorter.

6. All of the meridians meet at the north and south poles and split apart at the equator. The ends are called points.

7. At right angles, meridians and parallels meet.

8. As an angle, the azimuth is measured from geographic north to 360 degrees in a clockwise direction. The angle measure is followed by either N or S.

9. The equator is the "great circle," and other lines of latitude that are parallel to it are "small circles." All great circles are the same size, and all meridians are the same size and length.

10. Everywhere on Earth, scale is the same.

b) Primary data sources

Ans) Primary data are the ones that the researcher or user collects himself or herself. This is first-hand information that was gathered for the first time for a specific reason. When there is no secondary data for the subject, time period, or unit of study that is being studied, a primary survey is needed. It is mostly gathered with the help of well-defined methods and tools for gathering data. Some of these methods are surveys, observations, experiments, questionnaires, personal interviews, and so on. In geographical studies, we also divide geographical data into physical data, which is mostly about space, and socio-economic data, which is mostly about people.

There are four kinds of scales used to measure data.

1. Nominal Scale is a type of scale that uses numbers to represent identities, with no numbers representing size or weight, such as 1 for men and 2 for women.

2. In Ordinal Scale, numbers show the order of quality or quantity without giving the size of the quantity or the level of quality. For example, 1, 2, 3, and 4 mean "very good," "good," "moderate," and "poor," respectively.

3. Interval Scale has numbers that stay the same and show how big the difference is. But it uses zero as a starting point, even though there is no real zero in things like temperature.

4. Ratio Scale has numbers like an interval scale, but a true zero means that the thing being measured, like weight or height, is not there.

Surveys are the way that information is gathered. There are two types of these surveys: socioeconomic surveys and physical or spatial surveys. Socio-economic surveys are done to get information about things like population, social and economic development, politics, education, health, etc. You will like and learn that this kind of survey tries to cover a wide range of socioeconomic issues related to the development of the people, society, and country as a whole and with everyone's participation. Physical survey, on the other hand, includes reconnaissance survey, virtual survey using satellite images, field mapping, sample collection, land use and land cover survey, landforms identification and geomorphological mapping, landform association, morphometric survey, environmental survey, ground water survey and mapping, forest, soil, agricultural, wildlife, ground water quality, cadastral or property survey, etc.

c) Line diagrams

Ans) A line diagram is a straightforward and common type of diagram in which the facts are shown with the assistance of one or more lines. This line is drawn with reference to two coordinates. The X-axis refers to the horizontal direction, and the other coordinate refers to the vertical direction. The other is in the direction of vertical motion and is denoted by the letter y. The point at which the X-axis and the Y-axis originates serves as ‘zero’ or ‘starting point’. The measurement along the X-axis is termed the abscissa, while the measurement along the Y-axis is called the ordinate. The X-axis shows independent factors such as months, years, states and nations etc. whereas Y-axis shows dependent variables such as temperature, population and production etc. With this fundamental background, let us understand the basic points to be kept in mind while drawing line graphs.

Points to be Considered for Drawing Line Graphs

1. When choosing a scale, it is important to take into account both the highest and lowest values of the data that is provided as well as the dimensions of the paper.

2. The axis that represents variation across time or space is called the X-axis, and the axis that represents data is called the Y-axis.

3. It is important that the graph include accurate labels. Labelling should be done in a horizontal orientation as much as possible in order to make reading it easier.

4. When drawing more than one line on the same graph, you need to use a different style of line each time. For illustration purposes, if there are to be four lines drawn, they can be simple lines, broken lines, dotted lines, or broken lines with a dot in between each broken line.

Types of Line Graphs

Line graphs can be broken down into a few distinct categories. On the other hand, the following line graphs are more common and are utilised extensively for displaying statistical data:

1. Simple Line Graph

2. Combined Line and Bar Graph

3. Polygraph or Multiple Line Graph

4. Compound Line Graph or Band Graph

d) Choropleth maps

Ans) Choropleth maps are a type of thematic map that use colours or shading to represent data within defined geographic areas. These maps are commonly used to show patterns or variations in data across different regions, such as population density, income levels, or voting patterns.

The basic concept behind a choropleth map is to divide a geographic area into smaller regions, such as counties, states, or countries, and then assign a colour or shading to each region based on the data being represented. Typically, darker colours or more intense shading are used to represent higher values of the data, while lighter colours or less intense shading are used to represent lower values.

Choropleth maps can be used to show a wide range of data, including quantitative data such as population, income, or unemployment rates, as well as categorical data such as political affiliation or land use. They can also be used to compare data across regions or to track changes in data over time.

One of the main advantages of choropleth maps is that they are visually striking and can quickly convey complex patterns or trends in data. However, there are also some potential limitations and drawbacks to consider when using these maps:

1. Data Classification: Choosing the right data classification scheme can be challenging, and different schemes can lead to different interpretations of the same data. Common classification schemes include equal interval, quantile, and natural breaks, each of which has its own strengths and weaknesses.

2. Map Projection: Choropleth maps can be affected by the choice of map projection used to represent the data. Depending on the projection, some areas may appear distorted or misrepresented, which can affect the accuracy and interpretation of the data.

3. Small Sample Sizes: When working with small geographic areas or sample sizes, choropleth maps may not accurately represent the data due to random sampling error or other factors.

Despite these limitations, choropleth maps remain a powerful tool for visualizing and communicating data across different regions. They can be used to identify patterns and trends in data, highlight disparities between regions, and inform policy and decision-making at the local, regional, and national levels. By carefully selecting the right data, classification scheme, and map projection, choropleth maps can provide valuable insights into a wide range of social, economic, and environmental issues.

e) Small Scale maps

Ans) Small scale maps are maps that cover a large geographic area with a small amount of detail. These maps are often used to provide an overview of a region, country or continent, rather than to show detailed information about a specific area. Small scale maps typically have a ratio of 1:1,000,000 or smaller, which means that each unit of distance on the map represents a larger unit of distance in the real world.

Small scale maps can be produced using a variety of techniques, including digital mapping software, photogrammetry, and satellite imagery. They can be used to show a wide range of geographic features, including political boundaries, topography, land use, and transportation networks.  One of the key benefits of small-scale maps is that they can provide a comprehensive overview of a region or country, which can be useful for planning and decision-making purposes. For example, a small scale map of a country can be used to identify major cities, transportation routes, and natural features such as rivers and mountains, which can inform decisions about where to locate infrastructure, resources, and other strategic assets.  Another benefit of small scale maps is that they can be easily shared and distributed, either in print or digital formats. This makes them a popular tool for educational, research, and outreach purposes, as well as for public information campaigns and disaster response efforts.

However, there are also some limitations to small scale maps that should be considered. One major limitation is that they can obscure important details and variations in data, particularly in complex or heterogeneous regions. For example, a small scale map of a state or province may not show important variations in climate, geology, or land use within different regions of the state.  Another limitation is that small scale maps may not accurately represent the real-world distances and sizes of geographic features. This can be particularly problematic when using small scale maps for navigation or other precise applications, where accurate distance and size measurements are critical. Despite these limitations, small scale maps remain an important tool for understanding and communicating information about large geographic regions. By carefully selecting the right level of detail, scale, and projection, small scale maps can provide valuable insights into a wide range of geographic, environmental, and social issues.

f) National Sample Survey (NSS)

Ans) The National Sample Survey (NSS) is a large-scale survey conducted by the Government of India to collect data on various socio-economic indicators across different regions of the country. The NSS is one of the largest and most comprehensive household surveys in the world, covering a sample of around 1.2 lakh households across the country.

The NSS was first conducted in 1950-51, and since then it has been conducted periodically, usually every five years. The survey is conducted by the National Sample Survey Office (NSSO), which is part of the Ministry of Statistics and Programme Implementation.  The NSS collects data on a wide range of topics, including household consumption and expenditure patterns, health and education, employment and wages, agriculture and livestock, and housing and infrastructure. The survey also collects data on special topics of interest, such as gender, migration, and social mobility.  The data collected through the NSS is used for a variety of purposes, including policy planning, research, and evaluation. The survey data is widely used by government agencies, academic researchers, and non-governmental organizations to analyze trends and patterns in various socio-economic indicators and to inform policy decisions.

One of the key strengths of the NSS is its large sample size and representative sampling methodology, which allows for accurate estimates of socio-economic indicators across different regions and population groups. The survey also employs a standardized questionnaire and data collection methodology, which ensures consistency and comparability across different rounds of the survey.  However, there are also some limitations and challenges associated with the NSS. One major challenge is ensuring the quality and accuracy of the data collected, particularly given the large sample size and the diversity of the Indian population. Another challenge is ensuring that the survey remains relevant and responsive to changing socio-economic conditions and emerging policy priorities.

Despite these challenges, the NSS remains a critical source of data for understanding and addressing a wide range of socio-economic issues in India. The survey plays a key role in informing policy decisions and shaping public discourse on issues such as poverty, education, health, and employment, and it will continue to be an important tool for understanding and addressing the complex challenges facing India in the years to come.