"A lot of their information was based on small plotdata and also estimates of what would be needed in the agronomic production of biofuels, " Dr Vogel explained.
They are what you get when you plotdata for poor and rich countries together at a given moment in time, but actual levels of various pollutants in any individual country plotted over time wiggle around a lot more.
In its simplest state, this is geographical data with a timestamp, but when you plot this data onto the scenery of a map and then create a shifting window into the scene through the sequence of time, you create a data-driven story.