International Migrants Day 2014: 4 ways to visualise world migration

Today, 18 December, is an important day. Yes, it’s exactly a week until Christmas, but it’s also the UN’s International Migrants Day.

For those of us who live in or are interested in cities, this day is particularly relevant – after all, the rapid urbanisation of the past century is, at heart, a story of migration. As Doug Sanders predicts in his book Arrival City, by the end of this century we may well be a “fully urban” species, which will involve the migration of between 2bn and 3bn people from urban to rural areas – whether that be within their own country, or internationally.

So in celebration of this fact, we’ve found four fun visualisations which show where we’ve been moving – in one case, since before the birth of Christ. (Which reminds us, it’s Christmas in one week).

1. Facebook users and where to find them

For last year’s Migrants Day, Facebook’s Data Science Team analysed anonymised user data on hometowns and current cities. They were looking for something in particular: something called coordinated migration, which is where large groups of people from one hometown end up in a similar current location. For example, they found that 67 per cent of people who listed Badagri, Nigeria, as their hometown lived in Lagos by the time data was collected in 2012.

The world map they produced is pretty hard to make sense of, so here’s a zoomed in section of Asia. The smaller blue dots are towns, while the larger pink dots are the “hubs”, which are attracting the most migration. The yellow areas are countries which showed the fastest urbanisation between 2000 and 2012.

Click for a larger image.

This is a useful tool for those of us interested in urbanisation, tracking those who move from towns to cities, or smaller cities to bigger ones. Helpfully, the data also combines international and internal migration, which most migration surveys keep separate and measure in different ways.

A couple of caveats, though: first, the data will inevitably be somewhat skewed by hilarious teenagers changing their location to “Batman, Turkey ” or “Mount Despair, Australia”. Second, the data could be self-selecting – people migrating to the states from Cuba, for example, are more likely to now be on Facebook, so migrations there might be overrepresented in the data.

2. Migration as a flow chart

The Peoplemovin flow chart visualises the World Bank’s country immigration figures as a flowchart. Unlike map-based visualisations, this shows even the tiniest flows of migrants – from the UK to Uraguay, for example. The size of a country’s bar on the left hand side shows its number of incoming migrants, while the left hand side shows the number of outgoing ones.

Here’s a section of the incoming migration to the US, which has the highest number of incoming migrants in the world:

Click for a larger image.

3. The migration of (Western) culture

This one’s a little unorthodox, but makes for fascinating viewing. This year, a team of historians and scientists used data which, almost uniquely among datasets, is available in some form over the past 2,000 years: the birth and death locations of “notable people” all over the world. The result shows how cultural centres have shifted through time – from early inter-European migration, through inroads into the US, Australia, southern Africa and Asia. The researchers made this video in conjunction with Nature magazine:

Of course, the result is skewed towards western culture (and is by no means gives comprehensive view of the world’s most important births and deaths). But as 2,000-year surveys go, it’s not bad.

4. The map

As you may have guessed by now, perhaps the most simplistic way to represent migration is through a series of lines drawn on a map from one country to another. It might be hard to fully and clearly represent the incoming and outgoing streams – but this method does at least offer an overview of a country’s main importers and exporters of people.

Take Morocco, where arrivals tend to come from Africa, the Middle East and Russia…