Assignment Code: BGGCT-133 / TMA / 2021 - 2022

Course Code: BGGCT-133

Assignment Name: General Cartography

Year: 2021 - 2022

Verification Status: Verified by Professor

Part-A

All Questions are compulsory and carries 10 marks each.

Q1. What are the basic elements of maps? Elaborate any four of them.

Ans) There are several fundamental elements of maps that they are based on. Maps cannot be complete without these key parts. Scale, projection, reference grid, symbols and labels, tidy line, titles, and accuracy are some of the essential elements.

Four of the elements are described below:

1. Scale

The ratio between the distance on the map and the actual distance on the ground is called scale. Because paper cannot always be of the same size as the area under representation, the representation of the earth or even a chunk of area on a sheet of paper is almost impossible without fixing a proportional geometric shape or symbols representing the features on the planet. As a result, the maps are made on little pieces of paper of various sizes, employing representational proportions in which a specific distance or size of portraying features on the paper corresponds to a definite proportionate size on the ground. A one-centimetre line on paper, for example, could represent a one-kilometre distance on the ground. This is referred to as 'Scale.'

2. Reference Grid

Though there are many various sorts of references to spatial locations, they can include pin codes, distance and direction from a given point, and home numbers (alpha-numeric). The placement of any spatial features on the map is defined by the grid reference. It can be in the form of latitude and longitude, as well as alpha-numerical grids for reference.

3. Symbols and Legends

The map employs a variety of symbols to depict spatial elements and phenomena, as well as their attributes. The legend lists the symbols used in a map and provides self-explanatory descriptions of important lines, polygons, points, colours, patterns, textures, intensity, alpha-numeric characters or tags, and so on.

4. Titles

The identities of any map are printed on the top of the map as titles and sub-titles. It includes information such as the name of the region, the theme, and the year/time period.

Q2. Differentiate between primary and secondary sources of geographic data with suitable

examples.

Ans) The following points highlight the key differences between primary and secondary data:

1. The term primary data refers to the data originated by the researcher for the first time. Secondary data is the already existing data, collected by the investigator agencies and organisations earlier.

2. Primary data is a real-time data whereas secondary data is one which relates to the past.

3. Primary data is collected for addressing the problem at hand while secondary data is collected for purposes other than the problem at hand.

4. Primary data collection is a very involved process. On the other hand, secondary data collection process is rapid and easy.

5. Primary data collection sources include surveys, observations, experiments, questionnaire, personal interview, etc. On the contrary, secondary data collection sources are government publications, websites, books, journal articles, internal records etc.

6. Primary data collection requires a large amount of resources like time, cost and manpower. Conversely, secondary data is relatively inexpensive and quickly available.

7. Primary data is always specific to the researcher’s needs, and he controls the quality of research. In contrast, secondary data is neither specific to the researcher’s need, nor he has control over the data quality.

8. Primary data is available in the raw form whereas secondary data is the refined form of primary data. It can also be said that secondary data is obtained when statistical methods are applied to the primary data.

9. Data collected through primary sources are more reliable and accurate as compared to the secondary sources.

Examples:

The national census data gathered by the government is an example of primary data, while data collected from online sources is an example of secondary data. Another researcher's primary data might be the secondary data gathered from an online source.

For example, after a successful national census, the government publishes the results via newspapers, online magazines, press releases, and other publications. Another government entity may require access to the census results in order to allocate the state budget for healthcare, education, and other purposes.

Conclusion

Primary data is original and unique data that is directly obtained by the researcher from a source according to his criteria, as can be observed from the foregoing explanation. Secondary data, on the other hand, is readily available but not pure because it has undergone numerous statistical treatments.

Q3. How do you represent climatic data through diagrams? Explain.

Ans) Climatic diagrams depict distinct weather elements for a certain place and time period. Few climatic diagrams drawn to illustrate climatic data include graphs, bar charts, combinations of graph and bar charts, and wind roses. A simple graph can be used to display the mean monthly temperature of stations. A multiple graph can be used to compare the maximum and minimum temperatures with the mean monthly temperature. To demonstrate the climate variances among stations, special climatic diagrams incorporate both bar and graph. Another type of climatological diagram is the hythergraph.

Example is shown in graph below:

1. Draw graph to show the average maximum and minimum temperature for Chennai city.

In the x axis, mark the months of the year. 1 cm = one month

In the y axis, mark the temperature after selecting suitable scale considering the lowest and highest temperature of the station. (1 cm = 2 degrees Celsius)

Climate diagrams, such as the ones seen above, are quick summaries of average climate factors and their evolution over time. Over the course of a year, the graphs show monthly averages of temperature and precipitation. A month is represented by each tic mark along the horizontal line. The diagrams begin with January in the left corner for the northern hemisphere and July in the right corner for the southern hemisphere.

Q4. What are the four types of line diagrams? Explain each of them with neat sketch.

Ans) Line diagrams are a simple and widely used diagram in which data is represented by a line or series of lines. This line is produced using two coordinates, one of which is the horizontal direction and is referred to as the X-axis. The other axis is the y-axis, which runs vertically. The origin of the X- and Y-axes is referred to as the "zero" or "beginning point." The abscissa and ordinate are the measurements along the X- and Y-axes, respectively. The X-axis depicts independent factors like months, years, states, and countries, while the Y-axis depicts dependent variables like temperature, population, and production, among others.

Four types of line diagrams are described hereto:

1. Simple Line Graph

This is a simple graph with only one line displaying only one element, as the name implies. This is one of the most straightforward to comprehend, make, and use.

2. Polygraph or Multiple Line Graph

The term polygraph literally means "many graphs." A polygraph, then, is a graph with two or more lines drawn on it. These lines depict two or more variables that are intertwined. This diagram is used to depict the interrelationships between variables in one region over time or between multiple areas over time. For example, a place's mean, maximum, and minimum monthly temperatures, birth and death rates, male-female, literate-illiterate population components, imports and exports, agricultural, industrial, and mineral and power resources, and so on.

3. Combined Line and Bar Graph

This is a unique sort of diagram in which a line graph and a bar graph are combined and drawn in the same frame. This diagram is mostly used to depict the temperature and rainfall of a location throughout the year. Temperature exists at all times and fluctuates on a regular basis. As a result, rainfall is represented by a bar graph.

4. Compound Line Graph or Band Graph

A compound line graph is a more complex version of a simple line graph. They display multiple layers of data and allow you to see the percentage of the total. The actual values are determined by the discrepancies between the points on neighbouring lines on a compound line graph. The compound line graph below illustrates this.

Part-B

All Questions are compulsory and carries 10 marks each.

Q5. What is graticule? Write important properties of graticule.

Ans) Graticules are lines that depict the earth's parallels of latitude and meridians of longitude. Graticules are a type of map that can be used to indicate location in geographic coordinates (degrees of latitude and longitude). The intersection of the equator and prime meridian defines the origin of graticule (0,0).

1. The important properties of graticules are described here assuming the earth as sphere.

2. The equatorial circumference does not equal the meridional circumferences because of flattening at the poles.

3. The length of the degree along the meridian is not constant and the meridian is equal to one-half the circumference or half the length of the equator.

4. No parallel in one hemisphere is equal in length to any other in the same hemisphere.

5. The spacing between meridians is equal along a given parallel.

6. The space between meridians decreases towards poles and all parallels decrease in length at higher latitudes.

7. All meridians converge toward the north and south poles and diverge toward the equator. The poles are points.

8. Meridians and parallels intersect at right angles.

9. The azimuth as an angle is counted clockwise from geographic north through 360 degrees and the angular measure is followed by either N or S.

10. The equator is the great circle and other parallels of latitude are small circles. All great circles have equal lengths; all meridians are of equal length and are equal to the equator.

11. Scale is the same everywhere on the globe.

Q6. What is seasonal characteristic of Indian weather? Discuss any two weather seasons of India.

Ans) The weather in India is extremely variable. While tropical monsoon rains batter the southern point of India, the north will be buried in thick snow.

Characteristics of Indian Weather

The Indian weather system is divided into four distinct seasons. Every season is marked by a wide range of meteorological conditions that change from year to year. The agricultural calendar in India aligns with and revolves around four major seasons in different parts of the country.

Season # 1. Cold:

Except for small deviations, this season is recognised for clear skies and pleasant weather. The prevalence of calm and mild wind systems can be considered as an example of variation. However, due to western disturbances, rainfall may fall on the mountainous Kashmir, Gangetic, and Punjab plains, among other places. Most mountainous states straddling the north western to easternmost frontiers, including Jammu & Kashmir, Himachal Pradesh, Uttarakhand, Sikkim, and a few other north-eastern states, may have snowfall. When a cold dense air cools by the factor of radiation at high altitudes, this can happen. This results in foggy weather encompassing most of the plains and coastal areas, where there is a concentration of very large cities and cities with populations of a million or more people.

Season # 2. Summer:

The Summer Season is the one of India's four seasons that shows indicators of oppressive heat. Between the months of March and May, India's summer season begins. During this time of year, most sections of the country are subjected to strong winds and scorching heat from the sun. During this season, water scarcity affects several sections of the country. Temperatures readily range from 35°C to 45°C. Drinking water frequently throughout the day is the best strategy to keep ourselves feeling better. Taking fruits like watermelon, eating light meals, and drinking tender coconut water are all helpful ways to avoid becoming dehydrated.

The normal pressure magnitude characterises a hot weather season, except towards the end of the season, when it gets high. The pressure gradient, on the other hand, varies from gentle to moderate, and the direction of the gradient changes in response to the position of thermal lows. The western areas of the country, particularly Rajasthan, are subjected to harsh weather in the form of regular dust storms.

Q7. Differentiate between the choropleth and isopleth maps with suitable examples.

Ans) Choropleth and isopleth maps are two types of distributional maps used to show distinct geographical aspects in a region. They may appear identical at first glance, but their methodologies are fundamentally different, and they use distinct data.

Differentiates between the two methods.

Choropleth method

The four main Geographical variables are represented by different hues or shades of the same colour. For mapping purposes, you can use either continuous or varying data. Data bounds are defined by administrative boundaries, hence continuous data may be misinterpreted. The data range is classified into acceptable classes using the lowest and greatest values. Method of isopleth. Hue gradients or patterns enable map interpretation; the darker the colour, the higher the value of the data under consideration. Data such as population density distribution, for example, is commonly employed.

Example

For example, a state's literacy rate may be used as the mean, and the divergence of regional inequalities from this mean could be used to indicate real regional disparities. These maps can be used to emphasise a range of topics such as income level, literacy rate, and rainfall distribution, among others.

Isopleth Method

Isopleth maps make information about a region easier to understand by displaying areas with a consistent distribution. Lines can be used on isopleth maps to show areas with the same elevation, temperature, rainfall, or other characteristic; values between lines can be interpolated. Isolines, which are lines connecting points with the same value, are used to demarcate the data for the variable under consideration. The only data that is used is continuous data. A data boundary is not defined by administrative boundaries. Isolines define the data border. The drawing of isolines is determined by places with the same data value. The difference in these isolines determines the range. The closer the isolines are, the steeper the data distribution; the closer the isolines are, the easier it is to comprehend the map. Mostly used for real-time data such as temperature, rainfall, altitude, and so on.

Example

Isopleths can also employ colour to show regions with similar quality, such as a map with temperature ranges indicated by shades of red to blue. The lines or regions of an isopleth differ from those of a choropleth in that they are determined by the data rather than conforming to a pre-set territory, such as a political unit.

Part-C

Q8) Write Short notes on the following. Each question carries 5 marks.

Q8. a) Geoidal Earth

Ans) If other factors such as winds and tides were absent, the geoid is the shape that the ocean surface would adopt under the influence of Earth's gravity, including gravitational attraction and rotation. The continents are connected by this surface (such as with very narrow hypothetical canals). It is the "mathematical figure of the Earth," according to Gauss, a smooth but irregular surface whose shape arises from the uneven distribution of mass within and on the surface of the Earth. It can only be determined through significant gravity calculations and experiments.

Q8. b) Bonne’s Projection

Ans) Bonne's Projection is a type of conical projection named after the French cartographer Rigobert Bonne who invented it. It differs from the previous two projections in that all of the parallels are drawn to scale. Only one parallel, however, is considered a standard parallel, and its radius is calculated. Other parallels' curvature is determined by the standard parallel. All the parallels are divided independently and truly for drawing the meridians, and the points acquired are linked by smooth curves.

Q8. c) Agricultural Census

Ans) Agricultural censuses were first conducted in 1970-71 to collect data on socioeconomic groups and size classes, as well as other characteristics of land such as operational ownership, tenancy, land usage, and irrigation. Since 1970-71, the Agriculture Census Division, Department of Agriculture, Cooperation & Farmers Welfare, Ministry of Agriculture & Farmers Welfare, Government of India has conducted a full-coverage Agricultural Census every five years in partnership with the States and Union Territories. It is a part of the World Agricultural Census programme. For size classes-wise number and area of operational holdings, data is collected by social group.

Q8. d) LISS III and LISS IV sensors

Ans) LISS III

Linear Imaging Self-Scanning Sensor 3- LISS III is a remote sensing satellite camera from ISRO, India. The LISS – III camera provides multispectral data in 4 bands. The spatial resolution for visible (two bands) and near infrared (one band) is 23.5 meters with a ground swath of 141 kms. The LISS-3 sensor covers a 140-km orbital swath at a spatial resolution of 24 meters with a 24-day repeat cycle.

Liss IV

The LISS-4 Camera was launched onboard Resourcesat-1 satellite by ISRO in 2003. LISS-4 is a high-resolution multi-spectral camera with three spectral bands and having a resolution of 5.8m and swath of 23Km from 817 Km altitude. The panchromatic mode provides a swath of 70Km and 5-day revisit. LISS-IV sensor provides a ground resolution of 5.8 m (at nadir) and can be operated in either of two modes: In Multi- spectral mode (Mx) LISS-IV covers a swath of 23 km.

Q8. e) Open Series Maps

Ans) Topographical maps are known as Open Series Maps (OSMs). DSMs are created on various scales utilising the Everest/WGS-84 Datum and Polyconic/UTM Projection, mostly for defence and national security purposes. OSMs, on the other hand, are printed in WGS-84 datum in UTM Projection. These maps are available to the general public, but they do not include any civil or military Vulnerable Areas or Vulnerable Points (VAs/VPs). OSMs with scales more than 1:1 million can be obtained from SOI in either analogue or digital format, or through a contract for a specific end purpose. For the purchase of digital maps, a licence agreement is required.

Q8. g) Drainage Pattern

Ans) A stream system's network of stream channels and tributaries develops a certain drainage pattern through time as a result of local geology variables. The structure and texture of drainage patterns or nets are used to classify them. Their shape and pattern change in response to the terrain and subsurface geology of the area. Where surface runoff is increased and soil materials give the least resistance to erosion, drainage channels form. Tectonic irregularity, the nature of the underlying rock strata, and the gradient of the ground all influence them. Drainage patterns are divided into concordant drainage and discordant or insequent drainage based on the relationship between topology and flow direction.