Recent warming in the high latitudes has prompted the accelerated retreat of ice caps and glaciers, especially in the Canadian Arctic. Here we use the radiocarbon age of preserved plants being exposed by shrinking ice caps that once entombed them. These ages help us to constrain the timing and magnitude of climate change on southern Baffin Island over the past ~ 2000 years. Our results show episodic cooling up until ~ 1900 CE, followed by accelerated warming through present.