DataViz on Kerala Floods 2018
Note: The data may have errors and must not be used as a reference material for scientific study or analysis. This work is an example of explorations in Data visualization and focus has been on the tool used. i.e. dygraphs.
Kerala, in the month of August 2018, suffered a disastrous flood owing to the unusually heavy rainfall in the region. Heavy rainfalls are not unusual in Kerala but this time the predictions by IMD showed 42 per cent excess rainfall since the beginning of June. By the month of August, rainfall increased by 164 percentage.
The visualization here shows rainfall in each day of the month of August for the 14 districts of Kerala. You will notice a rise between the dates of 8–10 August and 14–16 August. These are the periods when the rainfall was maximum in different regions of Kerala. This lead to an overflow in various dams which had to open up their floodgates to let the excess water flow out.
Poor dam management and the unusually excess rainfall are the prime reasons behind the flood.
Behind the Data Visualization
The rainfall data has been taken from the site rp5.ru and it has rainfall in mm for all the 14 districts of Kerala from August 1 to September 1, 2018. This period was the point in time when the areas were hit by the unusually heavy rainfall.
Understanding the data
The data I found were all separate for individual districts. Putting together the individual district data together, I could visualize it as follows in google sheets. This helped me to understand what the data could look like visually.
This was when it became quite clear that all the district suddenly received heavy rainfalls during the dates 7–9Aug and 13–17 August. The analysis of the data from this point became very easy.
The next step was to choose the correct encoding tool. I chose to visualize the data using dygraph. A simple dygraph allowed me to highlight individual districts along with the rainfall data for the selected period.
You can also click and drag over the graph to zoom into that particular period and double-click to zoom out completely.
I added another interactive feature to the graph which allows the user to click on the highlighted line graph to lock it. This helps in studying the rainfall pattern only for that particular district.
The yellow highlights were also added in the background to bring in the focus towards the periods when it rained excessively.
Conveying the insight coherently
The graph allows you to get a quick overview of the rainfall trends in the whole state of Kerala during the floods. The interactivity of selecting a particular district allows a user to look at the daily rainfall pattern of a district in relation to the others
Data Source: rp5.ru
