Under an emission scenario where atmospheric greenhouse gas concentrations are stabilized, previous work suggests that on centennial time scales the rate of global temperature increases would steady at significantly lower rates than those of the 21st century. As climate change is not globally uniform, regional differences in achieving this steady rate of warming can be expected. Here, we define a "Time of Steady Change" (TSC) as the time of reaching this steady rate of warming, and we present a method for estimating TSC with the use of General Circulation Model experiments run under greenhouse gas stabilization scenarios. We find that TSC occurs latest in low latitudes and in the Arctic, despite these areas steadying at very different absolute warming rates. These broad patterns are robust across multiple General Circulation Model ensembles and alternative definitions of TSC. These results indicate large regional differences in the trajectory of climate change in coming centuries.
Plain Language Summary In a future where greenhouse gas concentrations have been stabilized, it is expected that the rate of global warming will decrease to a steady and slower rate than that observed in the 21st century. We also expect that the time of arriving at this steady, slow state of warming will have regional differences with some locations steadying sooner than others. Here we examine the time it takes to arrive at this steady state of warming and probe the regional differences in this arrival time. To do so, we make use of a collection of climate models all run under identical emission scenario where the concentrations of greenhouse gases increase throughout the 21st century and are then held constant for the following two centuries. We observe regional differences in the time it takes to arrive at a slower, steady state of warming. In particular, the Arctic and tropics are the last to arrive at a steady warming rate. Because the climate signal has been found to first emerge in the tropics, this work suggests that low latitudes will experience the longest duration of rapid warming.