So you have hitch-hiked through Central America, stalked rare beasts in Madagascar and trekked your way through northern Chile. You're pretty well travelled, even if you do say so yourself. Before you get ideas about being an intrepid explorer, however, consider this: for all their wide open spaces and seeming wildernesses, none of these places can be described as remote in 2009. In fact, very little of the world's land can now be thought of as inaccessible, according to a new map of connectedness created by researchers at the European Commission's Joint Research Centre in Ispra, Italy, and the World Bank. The maps are based on a model which calculated how long it would take to travel to the nearest city of 50,000 or more people by land or water.
The model combines information on terrain and access to road, rail and river networks. It also considers how factors such as altitude, steepness of terrain and hold-ups like border crossings slow travel. With the brightest colours representing the busiest shipping lanes, the English Channel, Mediterranean Sea and South China Sea stand out as major trade routes. In this way, China's flourishing export trade is clearly revealed, with some of the world's busiest shipping lanes. Meanwhile, regions to the far north and south are left out in the cold, at least for now.
Based on satellite data from the US Geological Survey's National Imagery and Mapping Agency, one kind of map reveals the extent to which the world is riddled with roads. These can be further broken down to show road types, which dictate how quickly a driver can zip along them. Unlike roads, which can evolve out of any old dirt track, railways require skilled labour and considerable investment. As a result, they are confined mainly to the richer nations of Europe, the US, Australia and Japan. Railway networks in India, Argentina and parts of Africa give clues to their colonial heritage.
The study also shows how, in areas where no roads penetrate, such as the Guiania region of eastern Colombia, river travel is simply the quickest way to get around. The mapping model assumes a river travel time of three minutes per kilometre, though its creators point out that this will vary with flow, season and political stability. From this kind of analysis, it turns out that less than 10 per cent of the world's land is more than 48 hours of ground-based travel from the nearest city. What's more, many areas considered remote and inaccessible are not as far from civilisation as you might think.
In the Amazon, for example, extensive river networks and an increasing number of roads mean that only 20 per cent of the land is more than two days from a city - around the same proportion as Canada's Quebec province. The news that only 10 per cent of the world is more than 48 hours travel by land or sea from the nearest city raises an obvious question. Is the level of connectedness that the other 90 per cent enjoys a good thing or a bad thing?
For humans there's little doubt that easy access to hospitals, schools, and centres of culture and trade is probably an advantage. For wildlife, however, the maps give a less positive picture. The tropical forest biologist William Laurance, of the Smithsonian Tropical Research Institute in Brazil, calls it "alarming" that only 20 per cent of the Amazon is more than two days travel from the nearest city, since that leaves the forest increasingly open to logging, wildfires and interference.
With Africa expected to reach the level of connectedness seen already in Europe in just a few decades, where does that leave the continent's animal species? The maps also reveal that the world's most remote place is on the Tibetan plateau (34.7°N, 85.7°E). From here, says Andy Nelson, a former researcher at the European Commission, it is a three-week trip to the cities of Lhasa or Korla - one day by car and the remaining 20 on foot. Rough terrain and an altitude of 5,200 metres also lend it a perfect air of "Do Not Disturb".
The maps were created to show how the distribution of people affects their access to resources such as education and medical care and how we are increasingly pushing wildlife out of even the wildest corners of our planet. With this project as a baseline, Alan Belward, who leads the project, hopes to use this method to follow how emerging economies will change the face of the world, for better or for worse: "The true value will be in doing the map again."
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