Relating wedges to warming

Warming follows total emissions

The key idea is simple: lower emissions in the future means less warming. Global temperature responds to the total amount of heat-trapping gases we put in the air, accumulating year after year.

If governments continue with their current policies, the world is on course to be 1.9°C degrees warmer than pre-industrial times in 2050. By 2100, this rises further to 2.5°C.

If you deploy 20 wedges beyond this, temperatures in 2050 are only slightly lower, but by 2100 Earth can begin cooling, getting back to 1.5°C.

If we backtrack to a 'no policy' pathway, the world will be more than 2°C warmer by 2050, and temperatures then escalate to 3.7°C by 2100.

Effects compound over time

Each wedge has the same effect on temperatures in 2050: eight wedges cuts temperature by one-tenth of a degree. But they can have a 5x larger impact on temperatures in 2100, because cutting earlier keeps emissions lower for longer, and puts the world on a low-carbon path beyond 2050.

How the app turns wedges into degrees

In the game, you choose a baseline future and then add wedges on top. The temperature readout is calculated from the link between total emissions and warming, calculated from a large set of published climate model scenarios.