Warming versus land-intensive mitigation impact on biodiversity refugia across climate policy scenarios

Background: Biodiversity loss is expected to escalate with every increment of additional global warming. At the same time, land-intensive climate change mitigation strategies, such as afforestation and bioenergy (with or without carbon capture and storage), may further compound biodiversity loss. This duality of drivers of biodiversity loss in the context of climate change raises the question of how these drivers compare in terms of magnitude.

Objective: By combining spatial data on biodiversity refugia with spatial time series data on bioenergy crop plantations and afforestation for multiple scenarios with varying levels of climate action and overshoot, we compare land use-related and warming-related pressure on today’s biodiversity refugia. We evaluate different biodiversity recovery assumptions when returning from a temporary temperature overshoot, compare impacts across climatic zones, and explore differences between three different models, namely, AIM, GCAM, GLOBIOM, and IMAGE.

Preliminary results: We show how scenarios with more ambitious temperature outcomes result in higher potential land pressure on today’s biodiversity refugia areas as more land-intensive mitigation options are implied. Meanwhile, more decisive climate action, including more land-intensive mitigation options, substantially reduces the warming-related loss of today’s biodiversity refugia areas. Based on our analysis, we find that refugia loss due to warming is larger than refugia loss due to land-intensive mitigation if we assume no refugia recovery after peak warming. However, this changes towards the end of this century if we assume that temporarily lost refugia can be recovered and repopulated when returning from a temporary temperature overshoot.