Environment

Most environmental problems cross borders, so acting on them usually requires international cooperation — and cooperation is hard when the costs are local and the benefits are shared. Resource depletion and climate risk create political tension, and behind almost every case sits the same argument: can growth and sustainability be aligned, or not?

Where to look

• Arctic sea-ice melt and what it means for regional cooperation between Russia and Northern Europe.
• Cape Town's 2016–2018 drought and how a state managed the crisis.
• Forest loss in Gadchiroli, India — and why fixing environmental failure is politically constrained.
• Shale gas in the USA — how NGOs influence legislators.
• Airline carbon-offset policies — decisions taken at several political levels at once.

Concepts this challenge pulls on

Interdependence and global governance, obviously. But also sovereignty: a state's right to exploit its own resources runs directly into the collective cost of doing so.

Connections worth making

Health — air, water and heat are health issues before they are environmental ones. Poverty — adaptation costs money that the most exposed states do not have. Borders — a river or an air mass does not stop at one.