Global glacier response to temperature goals overshoot

Glaciers have a delayed response to climate change. As a result, glacier mass loss is expected to continue long after greenhouse gas emissions have stopped as they seek to reach a new equilibrium, with consequences for sea level rise, infrastructure and freshwater resources. However, most glacier projections stop in 2100 and use a small number of greenhouse gas emission scenarios that do not allow linking global temperature targets to glacier change beyond 2100. Here, we compute mountain glacier volume and runoff changes until 2300 under a large suite of synthetic greenhouse gas emission scenarios leading to various levels of overshoots and temperature decline after peak. We show that early temperature stabilization leads to less glacier loss than the overshoot “peak-and-decline” scenarios. We also discuss the potential relevance of global temperature overshoots on water availability from glaciers, before and after peak global temperature.