USA Toxic Emissions Map: A Carto Presentation

Introduction

Global warming is a very popular and serious topic of discussion in the present day.  Excluding a select few individuals, people are worried about how many resources we consume, and how that consumption affects the planet.  This topic is especially important to the United States of America, considering the country’s recent decision to opt out of the Paris Agreement.  With this dramatic turn of events, one has to wonder how much does the United States contribute to pollution?  And how does that correlate with the land we use?  The best way to showcase the answers to these questions is on a map.

Materials

The map-generating website Carto was the main tool used for the visualization of this presentation.  The datasets came directly from The United States Census of Geography and Environment, specifically the data regarding total land usage and total toxic emissions by state.  Since the Land Usage dataset did not include Washington DC, Alaska, Hawaii, or the island territories, the data was cleaned and modified so that both datasets matched each other.

Methods

The goal behind this presentation was to show a possible correlation between land usage and toxic emissions.  To illustrate this, one layer was dedicated to each dataset, and the opacity on the toxic emissions layer was reduced.  Specific toxic emissions (such as air emissions, oil spills, or on-site disposal) could be brought up by clicking individual states.  On the right, three histograms were made to showcase specific uses for land, whether it be forest land, range land, or cropland.

Results

The results of the presentation mostly line up with expectations, with a few surprises as shown below:

The darker areas on the map, such as Texas and Nevada, show the most amount of land usage as well as the most toxic emissions.  This is to be expected, as Texas is he largest state in the Union boasting a whole host of energy-producing businesses.  However, other densely-populated areas like New York don’t show similar emission levels.  If anything, New York and South Carolina are on the low end of the toxic emissions scale.  It’s possible that this is due to land usage being different in these states.  For example, New York does not have as much farmland as Texas, thus it doesn’t produce as much farm-related waste.

The histograms also contain troubling implications regarding land usage.  There are very few areas in the United States with forests, farms, or ranges.  Agriculture and nature appear to have given way for industrialization, although this is only a hypothesis given the current data.  Oddly enough, that dataset on land usage did not include cities, mines, or oil fields.  As such, this correlation is implied, but nothing more than that.

Moving Forward

As it stands, the datasets used for this map, while thorough in some areas, can be considered incomplete.  Land usage statistics from Alaska, Hawaii, and Washington DC would contribute to a more complete picture of the environment situation of the country.  Other forms of land usage, such as land used for mines and oil fields, would better fit the dataset regarding toxic emissions.  But since this data is absent from the US Census, more research on this subject will have to be conducted.