Estimating least-developed countries’ vulnerability to climate-related extreme events over the next 50 years

TLDR

Current international assistance for adaptation is more than an order of magnitude below what analysts estimate is needed, making the timing of vulnerability in least‑developed countries a critical issue. The study investigates when least‑developed countries will be most vulnerable to climate change, accounting for projected socio‑economic development, by applying an empirically derived model of human losses from climate‑related extreme events. Using high‑resolution climate projections, the authors generate 50‑year loss scenarios for Mozambique and extend them to 23 least‑developed countries, incorporating changes in exposure to extreme events and socio‑economic development trends that affect adaptive capacity. Results indicate that socio‑economic development may begin to offset rising climate exposure in the second quarter of the century, but vulnerability rises most rapidly between now and then, highlighting an urgent need for international adaptation financing.

Abstract

When will least developed countries be most vulnerable to climate change, given the influence of projected socio-economic development? The question is important, not least because current levels of international assistance to support adaptation lag more than an order of magnitude below what analysts estimate to be needed, and scaling up support could take many years. In this paper, we examine this question using an empirically derived model of human losses to climate-related extreme events, as an indicator of vulnerability and the need for adaptation assistance. We develop a set of 50-year scenarios for these losses in one country, Mozambique, using high-resolution climate projections, and then extend the results to a sample of 23 least-developed countries. Our approach takes into account both potential changes in countries’ exposure to climatic extreme events, and socio-economic development trends that influence countries’ own adaptive capacities. Our results suggest that the effects of socio-economic development trends may begin to offset rising climate exposure in the second quarter of the century, and that it is in the period between now and then that vulnerability will rise most quickly. This implies an urgency to the need for international assistance to finance adaptation.