The dataset provided had a good structure to it and didn't require any prep. I did however bring in some data of my own to add to the analysis.
I split the dashboard into four main questions:
- Have Tornados changed over time?
- Where do Tornados Occur?
- When do Tornados Occur?
- How does Magnitude differ?
The main focus of today was to try and find out WHY?
For the first section, a simple line chart showed and increase in the number of tornados over time. When I explored this further, I saw that this increase was largely due to the increase of smaller magnitude tornados around the 1990's. Before the 1990's, tornado records were mostly based on someone spotting one and reporting it to the National Weather Service. As most tornadoes are small and last only a few minutes, the number observed and reported will be considerably smaller than the true number that occurred.
For the second section, a map showed that there was a large concentration of tornados in the states in the Midwest. This was due to the warm, moist air coming in from the Gulf of Mexico colliding with the cold, dry, and dense air from Canada and/or the Rocky Mountains causes storm energy that is rare across the globe. The energy of the storms comes from the contrast of the temperature, pressure, humidity, and speed of the colliding storms.
The heatmap third section showed that although tornadoes can occur at any time of year, they are more common during a distinct season that begins in early spring for the states along the Gulf of Mexico. It also showed most tornadoes form in the late afternoon. By this time the sun has heated the ground and the atmosphere enough to produce thunderstorms.
The scatter chart in the fourth section shows that there is a clear correlation between the average temperature of a state and it's tornado density. This suggests that a warmer atmosphere contributes to an increase in tornado magnitude.