GIS for Starters: Encapsulated basics
Geographic Information System (GIS) is a computer based information system used to digitally represent and analyse various parameters of the globe. Popular use of GIS began in late 1970s and was initiated by Environmental System Research Institute Incorporation (ESRI) of Canada. Much of the credit for the early development of GIS goes to Roger Tomilson, a Canadian GIS specialist.
You may be aware that the earth’s surface not only comprises of spatial attributes, but has non-spatial attributes, which are non-graphic. To put it simply, map features can be quantified in terms of data, such as contours. This is a spatial data.
However when the information provides description about the characteristics of a map and also includes qualitative features, it is categorised as non-spatial. Well, parameters of the globe may have become clear to you, but what does digitally mean? Digitisation is nothing but the conversion of smooth lines, boundaries and so on, into a digital form to allow the computer to read it.
GIS is a computer-assisted system devised to store, retrieve, analyse and display spatial data arranged in a systematic manner. It can also be defined as a computer based system that provides the following sets of capabilities to handle geo-referenced data: –
- Data Input
- Data Management (data storage and retrieval)
- Manipulation and analysis
- Data Output
Geo-Reference
In some online mapping service, you may have seen satellite imagery. When these images are captured from a satellite or an airplane, they are just plain images, like photographs. But to display these images on a map, they need to be associated with map coordinates. This process is called Geo-Referencing. Once the image is associated with the map coordinates it can be overlaid on top of street maps.
Geo-Coding
When you type an address or a place name in the search box and in return the map shows a marker at the place. The process of associating an address or a place name with coordinates on the map is called Geo-Coding. In a spatial database this is done as a point layer with name of the place as an attribute to the point location. This is one way of Geo-Coding.
For addresses, the associated coordinates are not saved in a database directly, but computed using a method called linear referencing. The start and end addresses along a line segment are saved and intermediate addresses are interpolated and the coordinates are calculated.
With the knowledge of Geo-Referencing and Geo-Coding, it is now possible to link it to a database, which is nothing but a collection of information about spatial and non-spatial data and their relationship to each other.
Software
The software module is the core of GIS and should be application specific. It must be chosen according to the requirement. The functions of GIS software include storage, analysis and display of geographic information. QGIS – Formerly Quantum GIS, gVSIG, Whitebox GAT and SAGA GIS are some of the well-used free GIS softwares.
Map Creation
There are various techniques used for map creation for further usage in planning for a project. The map creation can be done by either an automated raster to vector creator, using vectorisation packages which convert directly from raster to vector, or manually vectorising, using the scanned images. These digital maps may be products of a survey agency or the result of satellite imagery.
GIS’s broad applications work in tandem with various fields from cadastral mapping, which is a map showing ownership of land-usually large in scale to accurately depict individual landholdings, to utility networks, topographic mapping, thematic cartography, surveying and photogrammetry remote sensing, image processing, computer science, rural and urban planning, earth sciences and geography.
It helps in urban planning, housing, transportation planning, architectural conservation, urban design and managing landscapes. Networking and Disaster Management is also its forte.
Recent Posts
Petrol in India is cheaper than in countries like Hong Kong, Germany and the UK but costlier than in China, Brazil, Japan, the US, Russia, Pakistan and Sri Lanka, a Bank of Baroda Economics Research report showed.
Rising fuel prices in India have led to considerable debate on which government, state or central, should be lowering their taxes to keep prices under control.
The rise in fuel prices is mainly due to the global price of crude oil (raw material for making petrol and diesel) going up. Further, a stronger dollar has added to the cost of crude oil.
Amongst comparable countries (per capita wise), prices in India are higher than those in Vietnam, Kenya, Ukraine, Bangladesh, Nepal, Pakistan, Sri Lanka, and Venezuela. Countries that are major oil producers have much lower prices.
In the report, the Philippines has a comparable petrol price but has a per capita income higher than India by over 50 per cent.
Countries which have a lower per capita income like Kenya, Bangladesh, Nepal, Pakistan, and Venezuela have much lower prices of petrol and hence are impacted less than India.
“Therefore there is still a strong case for the government to consider lowering the taxes on fuel to protect the interest of the people,” the report argued.
India is the world’s third-biggest oil consuming and importing nation. It imports 85 per cent of its oil needs and so prices retail fuel at import parity rates.
With the global surge in energy prices, the cost of producing petrol, diesel and other petroleum products also went up for oil companies in India.
They raised petrol and diesel prices by Rs 10 a litre in just over a fortnight beginning March 22 but hit a pause button soon after as the move faced criticism and the opposition parties asked the government to cut taxes instead.
India imports most of its oil from a group of countries called the ‘OPEC +’ (i.e, Iran, Iraq, Saudi Arabia, Venezuela, Kuwait, United Arab Emirates, Russia, etc), which produces 40% of the world’s crude oil.
As they have the power to dictate fuel supply and prices, their decision of limiting the global supply reduces supply in India, thus raising prices
The government charges about 167% tax (excise) on petrol and 129% on diesel as compared to US (20%), UK (62%), Italy and Germany (65%).
The abominable excise duty is 2/3rd of the cost, and the base price, dealer commission and freight form the rest.
Here is an approximate break-up (in Rs):
a)Base Price | 39 |
b)Freight | 0.34 |
c) Price Charged to Dealers = (a+b) | 39.34 |
d) Excise Duty | 40.17 |
e) Dealer Commission | 4.68 |
f) VAT | 25.35 |
g) Retail Selling Price | 109.54 |
Looked closely, much of the cost of petrol and diesel is due to higher tax rate by govt, specifically excise duty.
So the question is why government is not reducing the prices ?
India, being a developing country, it does require gigantic amount of funding for its infrastructure projects as well as welfare schemes.
However, we as a society is yet to be tax-compliant. Many people evade the direct tax and that’s the reason why govt’s hands are tied. Govt. needs the money to fund various programs and at the same time it is not generating enough revenue from direct taxes.
That’s the reason why, govt is bumping up its revenue through higher indirect taxes such as GST or excise duty as in the case of petrol and diesel.
Direct taxes are progressive as it taxes according to an individuals’ income however indirect tax such as excise duty or GST are regressive in the sense that the poorest of the poor and richest of the rich have to pay the same amount.
Does not matter, if you are an auto-driver or owner of a Mercedes, end of the day both pay the same price for petrol/diesel-that’s why it is regressive in nature.
But unlike direct tax where tax evasion is rampant, indirect tax can not be evaded due to their very nature and as long as huge no of Indians keep evading direct taxes, indirect tax such as excise duty will be difficult for the govt to reduce, because it may reduce the revenue and hamper may programs of the govt.