Introduction

One of the many names that New York City is famously known by is ‘Concrete Jungle’.  I thought it would be interesting to see how populated the city is by greens. NYC Parks & Recreation and partner organisations organised street trees census ‘TreesCount!’ in the year 2015, under which volunteers and staff collected data of trees in NYC. The data includes location, species, and health of the trees within all the 5 boroughs of New York City.

Tools and Datasets

I acquired the dataset from NYC Open Data. 

I prepared visualisations on a cloud based web mapping tool, Carto.

I used a dataset of NYC’s population per borough.

For mapping I required NYC’s shapefile.

Openrefine, data wrangling software.

Process 

It only takes uploading the dataset to Carto for the tool to map the coordinates onto a map. On the census data layer I set the style of markers to points and point size to 6. I colored the points by value of tree health. Green for good, yellow for fair, orange for poor and white for null. It instantly reflected on the map. Then I added legend to specify the meaning of the colors. I gave the markers a pop-up, set to click, which indicates the tree species and the borough it falls within. By adding a category widget I could present the quantity of the trees under each health label. I also added a category widget to mark the number of trees per borough. 

I had the layers for TreesCount! and NYC shapefile uploaded, and now I added the layer of NYC’s population per borough. I used Openrefine to calculate the number of trees per borough and copied the data to my new layer in Carto. I made two more layers in the same dataset which calculate tree density per borough’s population and per borough’s area. In the map, these columns were presented as 2 more category widgets. I could make it more interactive by giving the Tree/BoroughPopulation widget auto style, which reflected in the map as well. I only had to add a legend for specification. 

Reflection

Carto was effortless and interactive to use. The only thing which I struggled with was that I could not give the same colors to Trees/BoroughArea widget as Trees/BoroughPopulation. Since the categories represented the same boroughs on the map I wanted to have them all be the same colors, but couldn’t get around it.