The IPCC thinks it's likely that we'll need to use carbon-capture technology that can suck carbon dioxide out of the air and store it underground.
Some scientists think we could cool the planet with techniques that fall under the category of solar radiation management: limiting the heat Earth absorbs from the sun.
You can see how this strategy modifies the natural greenhouse effect — and the global warming effect caused by carbon dioxide emissions from fossil fuels — in the infographic below.
Other forms of solar radiation management would modify the skies in different ways to achieve similar goals.
But solar radiation management could cause devastating side effects.
Another geoengineering method that sometimes gets discussed but would be hard to control involves dumping iron into the ocean.
People could also geoengineer Earth's oceans by covering large parts of their surfaces in white foam.
As a last-ditch effort to avoid catastrophic sea-level rise, some scientists have suggested propping up parts of the Antarctic ice shelf.
Transforming the world's economic and energy systems in the next 10 to 20 years is incredibly difficult, but these geoengineering plans may be even harder to pull off. And we don't know if they'd work.
Plus, no geoengineering solution would fully solve the root cause of climate change.