Assignment ZUOANNA Conclution

Conclusion for Task 1

We detect some characteristics on the air pollution by drawing time series lines over the five years.
For proper analysis, we created three groups in the different combinations over the stations based on the different time period they recorded.

• From 2013 to 2016, we found that the concentration on P10 was extremely high on January and December every year, hence, we named it “U pattern”.
  
• In 2017, the data is only provided over two months, November and December. The days which are in more serious air condition were mainly concentrated on 8th, 11th to 13th, 25th to 27th and 31st which is the most serious polluted day in December.
  
• In 2018, the daily and hourly patterns can be observed based on the hourly readings provided over the year. We found that common pattern for concentration on P10 during the days is that the it went higher at night (20:00 to 0:00) and early morning (0:00 to 6:00).
  

Conclusion for Task 2

We analysed Sofia topography and metrological characteristics and explored how the sensors distributed over the city and their Coverage, Performance and Operation.

• The sensors are not only distributed in Sofia city but located all over the Bulgaria country. With the help of sofia_topo dataset, it was able to get the range of the longitude and latitude for sofia city thus filtered the data to keep only the sensor in Sofia. Then zoom in the sensors which are distributed only in Sofia city.
• Not all the sensors are working very well at all the time. Some sensor just recorded in the discontinuous time period.
• We find the specific sensors with relatively higher readings than others separately in 2017 and 2018 by using Treemaps, and go in details with its metrological characteristics by using Heatmaps.

Conclusion for Task 3

We connected our findings from Task1 and Task2 to analyse the comprehensive factors that lead to the serious air pollution in Sofia city.

• The higher pollution readings in Dec&Jan may lead by local energy industry for providing residential energy in the cold winter, and because of the lower temperature, people need more household fuel in these two months for getting enough heat during the winter.
  
• With the daily and hourly patterns, we also infer that the extremely higher pollution concentration are lead by the illegal discharge in the local the commercial, institutional, the three cement plants in Bulgaria – Devnya Cement, Zlatna Panega Cement, and Holcim – use RDF in their production cycle, effectively contributing towards Bulgaria’s existing air quality issue.
  
• Air pollution is a problem in Sofia City is due to its location in the Sofia valley, which is surrounded by mountains that reduce the ability of the air to self-clean.