“A mappa mundi [...] is any medieval European map of the world. [...] To modern eyes, mappae mundi can look superficially primitive and inaccurate. However, mappae mundi were never meant to be used as navigational charts and they make no pretence of showing the relative areas of land and water. Rather, mappae mundi were schematic and were meant to illustrate different principles. The simplest mappae mundi were diagrams meant to preserve and illustrate classical learning easily. The zonal maps should be viewed as a kind of teaching aid—easily reproduced and designed to reinforce the idea of the Earth’s sphericity and climate zones” (cited from Wikipedia).
What would a mappa mundi of our times look like? A modern equivalent of such a map would have to focus on those spaces of our planet that we have a less vivid imagination of than the physical shape of the world that in medieval times was a much less familiar view than it is today. The following gridded population cartogram generated over the whole surface of Earth could be such a contemporary depiction of the world. It divides the world into equal spaces of population realigning the map view to show the human planet in a similar way as mappae mundi showed the world centuries ago:
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The Space of Climate Change
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In the face of unprecendented occurences of extreme weather, loss of species, and pollution, it is clear that climate change is affecting our planet. We cannot afford to wait any longer to act. This quote from the Earth Day 2013 website outlines the theme for this year’s Earth Day campaign which runs under the motto Climate change has many faces.
As the Earth Day campaign points out, the stories of the impact of climate change are extremely diverse: “A man in the Maldives worried about relocating his family as sea levels rise, a farmer in Kansas struggling to make ends meet as prolonged drought ravages the crops, a fisherman on the Niger River whose nets often come up empty, a child in New Jersey who lost her home to a super-storm, a woman in Bangladesh who can’t get fresh water due to more frequent flooding and cyclones.”
All these tales have one thing in common: They are a story of our impact on planet Earth, but equally of the impact of a changing planet on human’s lives. Our species has become one that is not just living in the natural environment, but is one factor that changes the environment to a level that no other species did before. This is happening to an extent that geologists discuss whether this can be seen as a new geologic era. Nobel Prize laureate Paul Crutzen started promoting the idea of the so-called Anthropocene, a concept that has now left the scientific world and is increasingly entering the public debate regarding issues of global sustainability and humanity’s impact. Anthropocene.info is a project initiated by the International Geosphere-Biosphere Programme (IGBP) that aims to “to help visualize and better understand humanity’s geographic imprint in recent time.” Not only is it important to find better ways of understanding the complex interrelations of humans and their natural environment, to which visualisation can contribute, but also is it important to create a public understanding of issues relating to the challenges connected to global change.
Here is one example of a more challenging view existing knowledge that demonstrates how changing the view can make us rethink the way our natural environment is shaped. According to research by the US National Office of Oceanic and Atmospheric Research, “[t]he strongest hurricanes in the present climate may be upstaged by even more intense hurricanes over the next century as the earth’s climate is warmed by increasing levels of greenhouse gases in the atmosphere. Most hurricanes do not reach their maximum potential intensity before weakening over land or cooler ocean regions. However, those storms that do approach their upper-limit intensity are expected to be slightly stronger in the warmer climate due to the higher sea surface temperatures.”
This is relevant due to the impact of more frequent flooding and cyclones on humans mentioned earlier. So where are these spaces where this is relevant. We know from historic records where there are tropical storm tracks, and the emerging pattern on a normal world map may be familiar to some of us (see here). But what if we change the perspective and focus on the actual areas that have the highest density of tropical storm occurrences. Using the records from 1945 to 2008, this intensity can be turned into quantities which are suitable for visualisation using the gridded cartogram technique. The following map shows a gridded cartogram of tropical storm intensity visualised over land based on a 0.25 degree grid. The larger a grid cell, the more tropical storm activity has there been over the past >60 years, indicating where the most affected areas of tropical cyclones (with a sustained wind speed of ver 40 mp/h) has been and how the climate patterns shape the world in a highly relevant issue of the Anthropocene:
A Cold World
While much of Europe has been denied a white Christmas, many of us were still having a white snow cover while the clocks went forward for ‘summer’ time this weekend. But although it appears that this winter is never-ending, it mainly comes very late this year. The coldest of temperatures and the main snowfall arrived in February and March, while the early winter months were even above average in some areas of central Europe.
Regular observations are collected regularly by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite, which records data about the land surface temperature (i.e. “how hot the ‘surface’ of the Earth would feel to the touch in a particular location“, a different measure than the air temperature we see on the weather reports every day). This map shows the land surface temperature anomaly this March compared to the average temperatures from 1951 to 1980 projected on a gridded population cartogram where every grid cell is resized according to its total population. The projection used in this visualisation shows, how the world’s population was exposed to the temperature anomalies in the late spell of winter last month:
Earth at Night
In 2007 nature conservation organisation WWF initiated a campaign “encouraging households and businesses to turn off their non-essential lights for one hour to raise awareness about the need to take action on climate change” (Wikipedia). The campaign is called Earth Hour and always takes place at the end of March – this year on Saturday, the 23rd.
The Earth Hour campaign has motto of “uniting the world to protect the planet”, although certainly not everyone will join in switching off their lights at 8.30 pm to unite each time zone with a dark night sky (and there is criticism of campaigns like this). But the wealthier parts of the world will be the main focus, as large parts of the poor world live in relative darkness at night anyway. NASA’s composite satellite image of the world at night (as featured on this website before) that gives us an indication of where light pollution affects most of the night skies has just received an update recently. Earth at Night 2012 was published by the NASA Earth Observatory last December, promising nothing less that “It’s the end of the night as you know it; you’ll see fine.” The resolution and level of detail revealed in the data is stunning, so that I reworked my version of the Earth at Night in an equal population projection using a gridded cartogram transformation. The new gridded population cartogram of the Earth at Night gives an equally stunning insight into how human activity relates to the distribution of light at night, showing the already highlighted inequalities that became apparent in the old version of the map in even greater detail where large parts of the populations in Africa and also in some parts of Asia live in the shadows of the wasteful brightness of the wealthy world. The Earth at Night as seen by humanity – an image of an unequal world:
On the grid: Worldmapper and beyond
My research on gridded cartograms has its roots in the works of the Worldmapper project, which was originally released in 2006/07 and extended in the following years. While the first phase of the Worldmapper project has visually describes the world, mapping the national contours of hundreds of variables, it did so only in one way and a way easily open to criticism despite its novelty and wide scope. To tackle this, I conducted further research to help address these potential criticisms, to work on moving the resource beyond its simple descriptive form. This included a look at more theoretical issues of how world resources, flows and shares are understood, particularly visually understood – and how this can be improved.
The gridded cartograms are one of the key results of this second phase of the Worldmapper project to advance and improve the capabilities of the Worldmapper maps. So far we integrated gridded cartograms on the Worldmapper website only in form of the World Population Atlas that shows an extensive collection of gridded country cartograms. These are the first ever made compilation of maps showing population distributions in cartogram form at that level of detail for every country of the world, but there is more to the underlying technique than this.
Following the release of these first maps using a gridded cartogram approach, I have made progress not only in enhancing the accuracy and quality of these country-level maps, but also in advancing the technique to a stage where gridded cartograms can be utilised as an alternative map projection (explained and discussed in full detail in my PhD thesis). Some examples are shown on this website: One example for the new capabilities at country level is the map of population changes in Germany. At global level the example of agricultural spaces presented at last year’s Annual Meeting of the Society of Cartographers demonstrates their applicability not only for population-related issues, but beyond that for other quantitative dimensions with a new level of detail, but also new capabilities of showing additional layers of information that the original Worldmapper approach was not capable of achieving.
There sometimes is a certain confusion about the differences between the maps drawn in the first stage of the Worldmapper project (and that we carry on producing as well), and the new gridded cartograms. The following map series shows the differences by using the Worldmapper colour scheme applied to the different map types (for full clarity, the map series starts off with a conventional map projection):
Cartograma cuadriculada de la población de Ecuador
The people of Ecuador are going to the polls today, voting at the first general election after the constitutional court resolved the Democracy Code in 2012. This comes at an interesting time from a British perspective, as WikiLeaks founder Julian Assange still calls London’s Ecuadorian embassy his home. Ecuadorians may care little about this international diplomacy row, and some may be more interested in issues regarding press freedom in their home country. But after many years of economic uncertainty and political instability following the collapse of the banking system in 1999, many other questions will rate far more important at these elections in a country that is extremely diverse for its size, not only in its nature, but also its population.
“Ecuador is a patchwork of indigenous communities, including people of colonial Spanish origins and the descendants of African slaves” (quoted from the BBC Country Profile Ecuador). For a country of only 283,561 sq km size (slightly smaller than Nevada, as the CIA World Factbook puts it), Ecuador has a remarkably diverse natural environment: The continental area stretches from the tropical rainforests in the east over the Andean highlands to the low lying coastal zone. And 1,000 km westwards off the coast the Galapagos Islands form the volcanic outpost of the country.
The population of over 15 million people is concentrated in two of these four major regions: ‘La Costa’ – the coastal region – is home to Ecuador’s largest city Guayaquil (2.3 million people), while the capital Quito (1.6 million people) is located in ‘La Sierra’ – the highlands at an elevation of over 2,800 m above sea level). Despite their high altitude, the Ecuadorian part of the Andes is home to a considerable population almost equal to the coastal areas. The less accessible rainforest region as well as the the Galapagos Islands in contrast are home to only small numbers of people.
The distribution of Ecuadors population is visualised in the following gridded population cartogram (a ‘cartograma cuadriculada de la población ‘ in Spanish), which is a much improved display compared to the original version of this map that I created in 2009 for the World Population Atlas. The improved resolution is made possible by using the LandScan population data which in this case provides a better estimate for the real distribution of people than the SEDAC GPWv3 data. The map shows an equal-sized grid over the land area of Ecuador resized according to the total number of people living in each of the grid cells, so that larger grid cells reflect higher numbers of people, while depopulated areas almost disappear from the map.
The green to brown colours in the map reflect the altitude of the areas, so that the coastal and mountainous regions are clearly distinguishable. The transitional zones of intermediate shadings (and elevations) almost disappear from this map, which shows the relatively small numbers of people living where relief gradients are steepest. The rainforest region (La Amazonía, or also El Oriente as it is situated in the east) which makes almost half of the land area, is equally underrepresented in this map, as it is home to less than 5% of the population. This is the human shape of Ecuador:
