R Project: Analyzing Air Pollution Data

06 Oct 2016

I recently completed a project for one of my data science courses. The project’s goal was to have us use R’s graphics packages to explore data. The PM2.5 Emissions Data contained over 6 million observations across 9 years. I answered the questions in this assignment using the base plotting system, ggplot2, and dplyr packages.

The data for this project are available for download at the EPA website here.


PM2.5 Emissions Data.

Contains all of PM2.5 emissions data for ‘99, ‘02, ‘05, ‘08. For each year, the table contains number of tons of PM2.5 emitted from a specific type of source for the entire year.

file name: summarySCC_PM25.rds

Column names:

  • fips: county code

  • SCC: name of source

  • Pollutant: pollutant type; string

  • Emissions: amount of PM2.5 emitted, in tons

  • type: Type of source, i.e. point or non-point

  • year: year of emissions record

Source Classification Code Table.

Provides a mapping from the SCC digit strings in the PM2.5 emissions data to the actual name of the PM2.5 source. The sources are categorized in a few different ways from more general to more specific. For ex, source “10100101” is known as “Ext Comb/Electric Gen/Anthracite Coal/Pulverized Coal”.

file name: Source_Classification_Code.rds

The following assignment description was taken directly from my class.


The overall goal of this assignment is to explore the National Emissions Inventory database and see what it say about fine particulate matter pollution in the United states over the 10-year period 1999–2008. You may use any R package you want to support your analysis.


You must address the following questions and tasks in your exploratory analysis. For each question/task you will need to make a single plot. Unless specified, you can use any plotting system in R to make your plot.

  1. Have total emissions from PM2.5 decreased in the United States from 1999 to 2008? Using the base plotting system, make a plot showing the total PM2.5 emission from all sources for each of the years 1999, 2002, 2005, and 2008.

  2. Have total emissions from PM2.5 decreased in the Baltimore City, Maryland (𝚏𝚒𝚙𝚜 == “𝟸𝟺𝟻𝟷𝟶”) from 1999 to 2008? Use the base plotting system to make a plot answering this question.

  3. Of the four types of sources indicated by the 𝚝𝚢𝚙𝚎 (point, nonpoint, onroad, nonroad) variable, which of these four sources have seen decreases in emissions from 1999–2008 for Baltimore City? Which have seen increases in emissions from 1999–2008? Use the ggplot2 plotting system to make a plot answer this question.

  4. Across the United States, how have emissions from coal combustion-related sources changed from 1999–2008?

  5. How have emissions from motor vehicle sources changed from 1999–2008 in Baltimore City?

  6. Compare emissions from motor vehicle sources in Baltimore City with emissions from motor vehicle sources in Los Angeles County, California (𝚏𝚒𝚙𝚜 == “𝟶𝟼𝟶𝟹𝟽”). Which city has seen greater changes over time in motor vehicle emissions?

My Answers

  1. plot1.png, plot1.R

  2. plot2.png, plot2.R

  3. plot3.png, plot3.R

  4. plot4.png, plot4.R

  5. plot5.png, plot5.R

  6. plot6.png, plot6.R