What are some examples of global interdependence

Climate, the levels

The obvious case is the consequence of climate change, where my emissions of greenhouse gases affects your sea level and climate (and vice-versa). aerial or marine pollution and overfishing in the oceans are others.

In a more restricted sense, one nation may hold all or most of a resource needed by all. Many nations are unable to feed themselves, at least to present standards, and therefore need to trade with others.