While violence and poverty have been cited as the reasons for the exodus, experts say the big picture is that changing climate is forcing farmers off their land – and it’s likely to get worse

Thousands of Central American migrants trudging through Mexico towards the US have regularly been described as either fleeing gang violence or extreme poverty.

But another crucial driving factor behind the migrant caravan has been harder to grasp: climate change.

Most members of the migrant caravans come from Guatemala, Honduras and El Salvador – three countries devastated by violence, organised crime and systemic corruption, the roots of which can be traced back to the region’s cold war conflicts.

Experts say that alongside those factors, climate change in the region is exacerbating – and sometimes causing – a miasma of other problems including crop failures and poverty.

And they warn that in the coming decades, it is likely to push millions more people north towards the US.