The climate deal made in Paris last November didn't include cargo ships—despite the fact that shipping emits roughly as much climate pollution as the entire country of Germany (and more pollution than the 160 least-polluting countries to sign the agreement, combined).
A visualization from researchers at University College London and the digital journalism studio Kiln shows the scale of the challenge. At any given time, as many as 100,000 ships may be at sea, delivering iPhones from China to the U.S. or fish from Scotland to China. Roughly 90% of everything we buy arrives on a ship.
To make the map, the researchers pulled data from exactEarth, a company that tracks ships both by satellite and stations on land. By looking at each ship's number—the equivalent of a license plate—they were then able to match it with technical details such as the type of engine it had and its speed, and use that calculate carbon emissions.
When they started work on the map, they had 2012 data available, but they say that the number of ships would be only slightly larger now. Over time, however, as populations grow and incomes rise around the world, ship traffic could increase so much that by 2050, it could make up as much as 17% of total greenhouse gas emissions in the world.
"If that's happening in shipping, it's going to cause a problem for all other sectors of the economy—unless we get shipping to decarbonize at the same time as everyone else," says Tristan Smith, a lecturer in energy and transport at University College London and one of the creators of the map.
The researchers work on policy issues in shipping, often with the International Maritime Organization, and realized that most people know little about what goes on in the industry. "Being able to make this information a bit more accessible, make it more engaging and eye-catching, versus a 200-page report, which is what we normally produce—we thought that would be useful," he says.
For the designers, it was a new challenge. "We felt the data was intrinsically interesting, partly because commercial shipping is so crucial to international trade that visualizing it creates a fascinating X-ray of the world economy," says Duncan Clark, CEO of Kiln. "In addition, we were attracted to the scale of the dataset. Mapping an entire year of data interactively was something that hadn’t been done before."
For the researchers, being able to look at the data in a different way has helped them find new insights. "Just producing visualizations and animations like this can help reveal all sorts of information that you would otherwise have missed," he says. "Or it just helps to tell stories, and sort of shed insight and show you where to go looking for extra detail."
People in the industry have also used the map to discover new information. An oil trader, for example, noticed ships moving from Venezuela to China, even though those movements aren't publicly available. "Looking at this map, you can see tankers leaving certain ports and going to other ports, and that immediately tells you that maybe something interesting is happening that isn't declared in the official record," Smith says.
The researchers are hoping that the visualization can help underscore the need for regulations that push the industry to cut emissions faster than they are today. It's less a technological problem than a political problem. Some new designs for cargo ships use sails to help save fuel, and algorithms that find the windiest route. Others use low-carbon fuel or fuel cells, or heat recovery systems, or solar panels.
"There are lots of options," says Smith. "It's figuring out which of those work, and—if you look at the scale of the problem that we need to engineer—walking global stakeholders through the process. If we do think that the best answer is a biofuel or the best answer is a hydrogen conversion, then that's a major change in the global infrastructure and the way the shipping industry thinks and works."
The changes will benefit more than the climate—air pollution from shipping may cause nearly 40,000 premature deaths a year near ports in East Asia alone.
The International Maritime Organization will consider requiring new pollution cuts at a meeting in October.
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