Changing the Cone of Uncertainty

The cone of uncertainty is a feature of hurricane maps: it shows the potential paths a storm’s centre may take, not the areas at risk when it makes landfall. Not being in the cone does not mean you’re safe: that misunderstanding has the potential to put people at risk. A long piece in today’s Miami Herald reports that changes to the cone may be afoot.

New research from the University of Miami confirms what a lot of emergency managers already knew, that people don’t understand the cone, and the UM experts are working with the National Hurricane Center to reshape it. Meanwhile, one Miami-based TV station, WSVN Channel 7, has already changed the way it displays the cone for storms, starting with Category 1 Hurricane Nicole in November.

Here’s the UM’s news release about that study.

Previously: The Dangers of Hurricane Maps’ Cone of Uncertainty; Rethinking the Cone of Uncertainty.

How an Air Travel Map Was Used to Scare the Bejeepers Out of You

BBC News: “Here’s how a decade-old map showing global air travel was used incorrectly by news websites across the world, leading to headlines such as ‘New map reveals no country safe from coronavirus tentacles’ and ‘Terrifying map reveals how thousands of Wuhan travellers could have spread coronavirus to 400 cities worldwide.’” Blame the usual culprits. [Kenneth Field]

The Dangers of Hurricane Maps’ Cone of Uncertainty

The New York Times

The cone of uncertainty is a core feature of hurricane maps: it shows the potential routes a hurricane is likely to take (the path grows over time, as we’re less certain where the storm goes next). But it’s misinterpreted in ways that put people at risk. That’s the argument made by Alberto Cairo in an online infographic (and in print) in the New York Times last week: research reveals that people living along the edge of the cone are much less likely to prepare for the storm, even though the edge of the cone is one possible path for the centre of the storm—and the cone only covers 60 to 70 percent of the storm’s potential paths in any event.

Alberto Cairo goes into more detail about the problem, and the responsibility of both journalists and readers when faced with such visualizations, on his blog. His book, How Charts Lie: Getting Smarter About Visual Information, comes out from W. W. Norton next month.

Previously: Rethinking the Cone of Uncertainty.

Satellite Image Guide for Journalists and Media

Pierre Markuse’s Satellite Image Guide for Journalists and Media:

So you would like to use a satellite image in your article and you would like to explain it to your viewers? Here is a short guide covering some of the most frequently asked questions and giving some general explanations on satellite images. It by no means covers all aspects, as there are far too many types of satellite images, but should give you a good start to find out more on your own and maybe motivate you to create your own images, which has become quite easy and quick even with no prior knowledge of it.

Complete with examples of imagery, examples of how to use it properly, and links to resources.

New York Times Maps Receive Infographic Award

The New York Times

The New York Times Graphics Department was recognized at the 25th Malofiej International Infographics Awards, where the jury awarded the special Miguel Urabayen Award for the best map to two Times maps: “Trump’s America” in the printed category and “The Two Americas of 2016” (above) in the online category. Press release. [The History of Cartography Project]

The Financial Times Searches for a Better Election Map

The Financial Times
The Financial Times

Martin Stabe of the Financial Times looks at the paper’s options for displaying the 2016 U.S. presidential results. Which to use, map or cartogram? In the end, neither: they’re going with a dot map—a compromise “that attempts to take the best from the other methods.”

The white underlying geographic map places states in their familiar size, shape and location, allowing them to be identified quickly. Using a cluster of dots rather than a solid fill to represent the outcome ensures that the amount of red and blue on the map accurately reflects states’ weight in the election outcome, rather than the (irrelevant) surface area.

Like the tiled grid cartogram, the number of electoral votes in each state is easy to compare visually without counting or interpreting numbers printed on the map. Because each electoral vote is a discrete mark, it is possible to accurately represent the split electoral votes that are possible in Maine and Nebraska, or the possibility of a faithless elector.

Technical details and source code here.

Previously: A Primer on Election Map CartographyMore Election Cartography Primers.

More Election Cartography Primers

The New York Times

Today, print subscribers to the New York Times were treated to a fold-out map showing a choropleth map of the 2012 election results at the ZIP code level (above). “The map is part of a special election section that aims to help explain the political geography of the United States — identifying where people who are conservative and liberal live and pointing out how physical boundaries, like the Rio Grande and the Cascade Mountains, often align with political ones,” writes the Times’s Alicia Parlapiano.

Parlapiano’s piece is in fact a lengthy tutorial on how to read election maps, along the lines of the pages I linked to in last week’s post on election map cartography—it outlines the problems of state-level election maps and choropleth maps that privilege area over population, for example, and shows some other ways of depicting the results.

It can’t be a coincidence that in today’s Washington Post we have Lazaro Gamio’s article dramatically highlighting the difference between area and population size with comparative maps. Mark Newman’s cartograms also make an appearance.

I can only conclude that both the Times and the Post are making efforts to educate their readers before the election results start coming in, one week from tonight. (Deep breath.)

Fewer Maps, But Better Maps

Alan Smith of the Financial Times adds to the conversation about when to use a map to present your data, when not to—he gives an example where a gridded infographic is a much better choice than a map—and when more than one map is required to tell the whole story. “So as lovers of maps, we are keen to create beautiful ones whenever they offer a crucial addition. Truly appreciating them, however, means not defaulting to a map just because you can. Like a lot of things in the world of data visualisation, the right way to use them is to follow the mantra ‘fewer, but better’.” [WMS]

Previously: The End of Maps in Seven ChartsDon’t Make a Map.

Don’t Make a Map

Martin Burch, data developer for the Wall Street Journal, has posted his presentation from the GeoJourNews 2016 conference. Called “Don’t Make a Map,” it explores situations where presenting your data in the form of a map is actually a bad idea, and looks at some better alternatives. “Always make a map,” he concludes, “but don’t always publish it.” Very much in the vein of similar pieces by Darla Cameron (of the Washington Post) and Matthew Ericson (of the New York Times). [Carla Astudillo]

Previously: The End of Maps in Seven Charts.