BACKSTORY-Mapping the world's growing plastic mountain, one bottle at a time

(Backstory is a series of reports showing how Reuters journalists work and the standards under which they operate)

SINGAPORE, Oct 7 (Reuters) - It’s one thing to say the world is drowning in plastic. It’s another to show it.

Data compiled by the United Nations show 8 million tonnes of plastic - bottles, packaging and other waste - enter the ocean each year.

Singapore-based Reuters Graphics Editor Simon Scarr wanted to create a way for people to visualize the scale of that waste, zeroing in on plastic bottles, a commodity that’s sold and discarded all over the planet each day.

Euromonitor International tracks specific types of plastic packaging sold annually around the world, including PET bottles, a lightweight plastic developed in the 1970s and widely used for bottled water and drinks. On a global scale, approximately 1 million plastic beverage bottles are sold every minute.

“The numbers were staggering but still really hard for people to comprehend what that really looks like,” Scarr said. “I wanted to visualise this as actual piles of discarded bottles.”

Scarr and Data Visualization Developer Marco Hernandez went to work to build a 3D model that would illustrate a simple thought experiment: What would it look like if the million bottles sold every minute around the world rained down on a single spot over 60 seconds?

The first inputs into the model were the mass and other properties of that one bottle from the vending machine in Hong Kong. To provide a sense of scale, Hernandez and Scarr decided to show the bottles tumbling down on a garbage truck and a human figure.

And to illustrate the hail of plastic, the 3D model assumed that the bottles would be dropped from a height of 49 meters, equivalent to a trash shower from the top of the Arc de Triomphe in Paris or Cinderella’s Castle in Florida’s Walt Disney World.

An early projection showed that the almost 17,000 bottles consumed every second would quickly bury first the human figure and then the garbage truck.

But plastic bottles bounce, tumble and roll on impact so the model had to account for that messy distribution.

As Hernandez went to work on the visualization, the team hit a snag: his computer was not powerful enough, especially when he and Scarr decided to make the virtual vantage point shift during the storm of bottles. Even running a single computer around the clock, it took 9 days to render the first visualization.

The work-around was to connect a dozen Reuters computers in Hong Kong, Singapore, Bengaluru and London into what became an ad hoc “render farm” to harness the computational power needed to make and edit the animation.

Finally, the team wanted to show what the world’s discarded pile of bottles would look like after an hour, a month a year and a decade if every bottle used on the planet had been thrown into a single heap.

To illustrate scale, landmarks like the 830-meter-tall Burj Khalifa in Dubai were shown for comparison and virtually buried.

Four trillion plastic bottles have been sold and discarded over the past decade. That plastic pile would reach 2,400 meters, about the height where hikers can develop altitude sickness.

Scarr and Hernandez experimented with showing that plastic mountain superimposed over parts of Manhattan for scale and toyed with the idea of showing the trash evenly distributed across the island like a flood.

In the finished version, the virtual plastic mountain shifted to Queens so that viewers could peer across the landmarks of Lower Manhattan for a sense of relative scale.

Click here to see the finished graphic as published (Writing by Kevin Krolicki; Editing by Raju Gopalakrishnan)