Sea Level Rise Damages on Ecosystem Quality─A Life Cycle Impact Pathway

Abstract Climate change causes species extinction not only by the direct increase in surface temperatures but also by indirect mechanisms, like sea level rise (SLR). These indirect mechanisms are rarely integrated into environmental impact assessment methods, such as life cycle assessment (LCA). In this study, we address this gap by outlining a new impact pathway within the life cycle impact assessment framework that links greenhouse gas (GHG) emissions to ecosystem damages via climate change-induced SLR for 244 different GHGs. We use the latest global digital terrain model with corrected referencing between sea level and coastal elevation for a new globally differentiated and open-source flood model predicting the areas flooded by SLR with a spatial resolution of 1 arc-second (∼30 m). The effects on ecosystems are quantified by computing the potentially disappeared fraction of species caused by flooding in coastal ecoregions worldwide for five terrestrial taxa. A spatial analysis of the results shows that vascular plants and reptiles face the highest extinction risks from SLR, with regional hot spots identified in Central America and across many islands of Southeast Asia. We recommend integrating the developed impact pathway into the LCA framework to better capture impacts to species-rich and particularly vulnerable coastal ecoregions.