Earthquake risk zones: A people’s perspective

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A M7.8 earthquake has occurred in Nepal “as the result of thrust faulting on or near the main frontal thrust between the subducting India plate and the overriding Eurasia plate to the north.” As the USGS summarises, “although a major plate boundary with a history of large-to-great sized earthquakes, large earthquakes on the Himalayan thrust are rare in the documented historical era. Just four events of M6 or larger have occurred within 250 km of the April 25, 2015 earthquake over the past century”.
In a paper for the Journal of Maps published in 2014 I have analysed and visualised data documenting earthquakes that have occurred since 2150 BC. The following map was part of the material supplementing the publication showing the results of the analysis shown on an equal population projection. The gridded cartogram gives every person on the planet an equal amount of space while highlighting the most densely populated spaces in relation to the earthquake risk (calculated via the intensity of earthquakes recorded since 2150 BC). Also shown are the world’s megacities (over 5 million population). The map shows the large populations that make even Nepal (with its almost 28 million people) much more visible than it would be on a conventional map, highlighting why this event turns out to be quite disastrous. The map also shows what the USGS statement above mentions that Nepal is amongst the areas in the region which are far less subject to major earthquakes (as indicated by the yellow to blue shading in the map there – Nepal is the rather large spot squeezed on top between the areas that represent the large populations of India and China):

Map of earthquake risk zones on an equal-population projection
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Volcanoes and Human Population

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The Calbuco volcano in southern Chile erupted for the first time in more than five decades, which in the global media was covered more for its visual spectacle rather than its perception as a major catastrophe. This can be partly explained with the low threat that Calbuco poses to larger numbers of people. As reported by the BBC, “authorities have declared a red alert and evacuated more than 4,000 people within a 20km (12 mile) radius”. This is a relatively low number as the volcano is situated in a sparsely populated, mountainous area. Natural events usually turn into natural disasters when they happen in more densely populated areas. The following map shows how human settlement patterns and the global distribution of volcanoes correlate by drawing a 100km radius around each of the world’s volcanoes and then projecting this data onto a gridded population cartogram. This equal-population projection results in some of these 100km risk zones around the volcanoes to become hugely visible, because there are large populations living in this area, while other volcanoes and their risk-radius become almost invisible due to the low number of people living there. Very often, these are the decisive differences between a volcanic eruption being a natural event (or even spectacle) and a natural disaster, which these events can become in the red-shaded areas of this map:

Map of volcanic risk zones on an equal-population projection
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Healthy Soils for a Healthy Life

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International Year of SoilsHealthy Soils for a Healthy Life is the motto of the UN International Year of Soils which aims to “increase awareness and understanding of the importance of soil for food security and essential ecosystem functions.” As explained on the campaign’s website, “soil is the thin layer of material on the Earth’s surface. It is a natural resource consisting of weathered and organic materials, air and water. As it is the medium in which plants establish themselves and grow, the most widely recognized function of soil is its support for food production. Soil provides nutrients and water that are absorbed through plant roots and contribute to the regulation of water and atmospheric gases and therefore play an important role in climate regulation.”
Soil therefore matters most where is is near human population, which at the same time puts soils under extreme pressure in these areas. Soil types not least determine where humans used to settle when they gave up their nomadic lifestyles and started becoming more stationary as farmers. Nowadays, some of the most fertile soils are found in the most densely populated spaces on the planet, which is shown in the following map. The map shows the major soil types classified in the FAO/UNESCO Soil Map of the World reprojected on a gridded population cartogram where a grid is resized to give every person living within a grid cell an equal amount of space (reducing the map in those spaces most where there are fewest people):

Map of major soil groups
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Death Penalty

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Amnesty International has launched its most recent report on Death sentences and executions in 2014. In their annual report they publish the minimum figures of recorded death sentences and executions that they are able to verify. For producing a Worldmapper-style cartogram, absolute numbers are essential of course, which requires some decisions to be made which numbers go into the map transformation. For the following two maps, showing the death penalty executions and sentences in 2014, the minimum figures of validated cases provided in the report were used, or, where these were not stated, the estimated figures as stated in the report were used instead (China was set to 1000 to not dominate the cartogram entirely, even if the number is believed to be much higher than that). The maps therefore need to be seen as a general picture of the state of death penalty in the world, rather than the exact reality. As stated by Amnesty, “the real number of people executed is much higher. There are no figures for China, for example, which is believed to execute more people than the rest of the world put together. Other countries like Belarus also execute prisoners in secret, often without informing the detainees’ relatives or lawyers.”

Map of death penalty executions in 2014
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The Evolution of Life Expectancy in the World

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Life expectancy equals the average number of years a person born in a given country would live if mortality rates at each age were to remain constant in the future.” (Wikipedia)
Depending on the exact sources, global life expectancy currently lies at approximately 71 years although a global estimate tells very little about the differences between the countries. What applies to every country is the fact that women, on average, live longer than men.
The following map shows the distribution of life expectancies based on national-level data as documented in the 2014 revision of the Human Development Report displayed on a gridded population cartogram in which every human gets an equal amount of space:

Gridded Population Cartogram showing Global Life Expectancy in 2013
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Visualising your UK constituency

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The UK general election is fast approaching. Following the first almost-debate of the would-like-to-be Prime Ministers the battle for the ‘correct’ interpretation of the state of the nation has come into its final stage. Statistics are easy to twist, and there is never an absolute truth in them. In a collaboration with the Office for National Statistics I was involved in the creation of a little interactive visualisation feature that sheds light on some key statistics that show life in the constituencies around the country. Using a conventional map and a hexagon cartogram of the United Kingdom we looked at house prices, income, public sector employment, education, age, migration, and health which can be interactively explored and compared in both map views. The following map is one example from that feature, showing the share of people not born in the United Kingdom:

Cartogram and map showing the share of the population born abroad in the United Kingdom
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