Greenhouse gas emissions are causing the Earth to warm up, but the strength of the Atlantic Ocean's circulation can affect how quickly this happens. Two climate models show that a weaker circulation leads to faster warming of the surface ocean and slower warming of the deeper ocean, resulting in a higher overall warming response. A stronger circulation, on the other hand, causes a slower warming of the surface ocean and a smaller overall warming response. This means that the strength of the Atlantic Ocean's circulation can impact how quickly the climate warms up over the next hundred years.