Historical and economic connections between countries also play a part in regional migration-flows that are often ignored by international media, such as those from former Soviet states to Russia. Often times the scale of this kind of migration is hidden because the receiving countries also have a high rate of out-migration, resulting in negligible net migration figures.

Furthermore, whilst citizens in Western countries often see themselves uniquely as victims of a mass migration that imbalances their populations, they would do well to understand that other parts of the world are already defined by such imbalance. Lebanon for example, is home to a far higher proportion of people born elsewhere than the vast majority of Western countries. In fact, Lebanon is currently playing host to over 1.5million Syrian refugees, yet its native population is only 4 million. We cannot yet predict how many of those will stay.

The causes or triggers of this scale of migration are complex. War and conflict are certainly drivers that show no signs of abating, whilst climate change, or rather the localised effects of climate change, are also beginning to have the kinds of displacement impacts predicted over the last two decades. The UNHCR suggests that 2015 saw global records in terms of the number of people who have been forcibly displaced, claiming: “one in every 122 humans is now either a refugee, internally displaced, or seeking asylum.” Meanwhile the factors that lie behind movements to find better economic opportunities, escape from persecution or to gain better access to natural and societal resources are all being exacerbated by regional population growth and widening wealth and access inequalities.

Often, attempts are made to categorise different kinds of migration and migrant according to those factors that push and pull. Commentators talk of ‘climate migrants’, ‘refugees’, ‘asylum seekers’, ‘political migrants’ and ‘economic migrants’. But whilst some of these terms have formal legal definitions, the reality is that it is often difficult to distinguish one from another; someone migrating from a warzone may have had their home destroyed or they may be suffering from the deleterious economic impact that war is having in their region, for example.

The impacts of mass migration are manifold. The most visible perhaps, are changes in social attitudes reflected in popular and social media comment, as those in receiving countries or receiving cities vocalise perceived threats posed by immigrants to their culture, livelihood and security. These changes in social attitude often lead to macro-level policy shifts. Recent trends in Western migration policy discussion and rhetoric, from all sides of the political spectrum, for example, all seem to point towards a coming slew of ever-more draconian laws and policies designed to discourage immigration. Further weakening of immigrant rights and benefits, tougher asylum rules and tighter border controls are a given, but formal criminalisation and harsh penalties for certain types of migrant, and even military intervention in border-lands, are not impossible in the future. Some of these measures will challenge the very fundamentals of the national ideologies and constitutions that are producing them, causing anguished national soul-searching; a phenomenon we are already witnessing in relation to the plight of the Syrians.

In other parts of the world, more measured (but no less important or restrictive) policies have been designed to slow or halt rural-urban migration, such as the implementation of China’s infamous ‘hukou’ system of residency rights or rural tax and investment incentive schemes in places like Mozambique. And at a more local level, cities have been forced to rethink the ways in which they plan their infrastructure and services to cope with fast-rising and sometimes statistically invisible populations. Most are eager to avoid the pitfalls of the past that have manifested themselves in squalid slums and shantytowns. In these responses we may also see the seeds of a more balanced approach to weighing the pros and cons of migration in specific regions.

So what of the next ten years? Well, if the consensus of those we spoke to is to be believed, we ain’t seen nothin’ yet! The displacement of people due to the effects of climate change looks set to become a feature of the 21^st century as coastal areas become more prone to severe flooding, extreme weather events become the norm, and arable land and fresh water become ever more scarce. Rising economic inequalities will also push even more people to move in search of better jobs (even as automation and robotics eat away at traditional employment sectors in receiving countries and cities): People trafficking, of both voluntary and involuntary migrants, is likely to become too profitable a business to prevent. And local population growths will increase pressure on localised resources, leading more governments to encourage emigration in the hopes of easing local pressures and benefitting from the remittances of overseas Diasporas.

Despite the bluster emanating from certain politicians, the scale of migration and prediction of its impacts are actually extremely difficult to measure, leaving statistical vacuums that are all too often filled with guesswork, cherry-picking and anecdote, leading to ill-informed and reactionary policy-making. However, over the next decade, as many as a billion people could be on the move and we will need to find sustainable ways of responding to this unprecedented human march.