The Carbon Map

פורסם: 11 בדצמ׳ 2013, 13:26 על ידי: Sustainability Org   [ עודכן 12 בדצמ׳ 2013, 5:13 ]
An interactive “squishy map” exploring national responsibility for and vulnerability to climate change. Created for the Guardian and the World Bank Apps for Climate competition. Spring 2012.

The brief

Climate change responsibility is conventionally discussed in terms of national emissions or emissions per capita. But that is a very one-dimensional view, as it ignores crucial factors such as historical emissions – most of which are still in the air – and the international trade both in fossil fuels and goods produced using those fuels.

To give a more nuanced picture we set out to map where the carbon is taken out of the ground in the form of oil, coal and gas, where it gets burned and where the resulting goods and services are consumed, plus cumulative emissions from the last 150 years and one view of potential future emissions in the form of each country’s estimated stocks of fossil fuel.


The conventional way to map national-level data is with a choropleth (shaded-in map). These are easy to make but they aren't particularly engaging or legible (a darkly shaded small country can look less prominent than a lightly shaded big country). In addition they allow you to view only at one dataset at once.

Another problem with interactive maps in general is that they can be a bit baffling for the user. There are lots of buttons and menus and markers but it can take a while for someone looking at it cold to work out what's going on.

Our approach

To make the data as engaging and clear as possible we decided to reinvent the area cartogram – a map which distorts the size and shape of nations to reflect the data being displayed. These have been popular in books, posters and online as still images, but we wanted to make them more tactile and legible by animating between different datasets. This was done with an SVG implementation of a publicly available algorithm by Mark Newman (which works, ingeniously, by simulating the diffusion of chemicals between areas, as described in this paper by Newman and Michael Gastner).

This approach makes it easy to see at a glance how each region or nation stands in terms of each metric. So here's historical emissions, for example, in which wealthy nations look relatively inflated – especially the UK, whose massive size reflects its pivotal roll in the coal-powered industrial revolution.

By contrast, on the vulnerability maps it's the poor world that looks too large. Here’s the world resized to show the number of people living less than five metres above sea level.

The other advantage of the interactive cartogram approach is that it allows the user to see how two different datasets correlate by allowing the maps to be shaded as well as distorted. For instance, if you shade the map by population growth and click between the various metrics, it's clear at once that high rates of population increase (the reddest areas) are very poorly correlated to carbon footprint…

… but very highly correlated to poverty.

Finally, we wanted to deal with the problem of interactive maps being baffling and expecting the user to do all the work in terms of working out what's going on. We thought about having an introductory video but that felt awkward. So instead, we decided to turn the whole map into a pseudo-video by adding a big play button that kick starts an audio introduction and moves the actual map in sync. This technique later became the basis of our Talkie toolkit.

Selected media coverage


Honourable mention, World Bank Apps4Climate.

Source: - click here
Type of maps (vertical menu):
Country sizes show actual land area. Most world maps don't show this accurately as it isn't possible to represent the globe as a flat map without compromising on either shape or area.

Country sizes show total population – which includes all residents except refugees. Asia balloons enormously, emphasising that more than half of the world's people live there.

Country sizes show total GDP, the sum of all the economic activity in each nation. The map is dominated by North America and Western Europe, which account for more than half the world's GDP, despite being home to less than a fifth of the global population.

Country sizes show the eventual CO2 emissions from oil, coal and gas extracted each year. Many of these fuels are exported rather than used domestically, but arguably the countries extracting and selling fossil fuels bear a degree of responsibility for the resulting emissions.

Countries are sized to show their annual CO2 emissions from fossil fuel use and cement production. This is the conventional way to view national emissions, but it ignores imports and exports of fossil fuels (the Extraction map) and goods and services (the Consumption map).

Country sizes show the carbon footprint of all goods and services consumed in a nation, including imports and excluding exports. Compared to the Emissions map, major exporters such as China shrink, while net importers such as the UK grow.

Country sizes show CO2 emissions from energy use 1850–2007. These historical (or 'cumulative') emissions remain relevant because CO2 can remain in the air for centuries. Europe and the US dominate, having released around half the CO2 ever emitted.

Country sizes show the potential CO2 emissions of fossil fuel reserves, calculated by converting each nation's estimated stocks of economically recoverable oil, coal and gas into the CO2 that result if all those fuels were burned.

People at risk
Country sizes show the number of people injured, left homeless, displaced or requiring emergency assistance due to floods, droughts or extreme temperatures in a typical year. Climate change is expected to exacerbate many of these threats.

Sea level
Country sizes show the number of people living less than 5m above sea level. Some low-lying populations will find themselves exposed to rising sea levels in the coming decades and centuries.

ountry sizes show the number of people living on less than 1.25 dollars a day. Poverty adds to climate change vulnerability because lack of access to health services increases the risks of climatic changes, and lack of access to capital makes it harder to implement adaptation measures.