Investigating the Vulnerability of Dry-Season Water Supplies to Climate Change: A Case Study of the Gwangdong Reservoir Drought Management System, Korea

Abstract

This study aims to improve the method to measure the vulnerability of water supply that arises mainly due to water scarcity in the dry season, and a situation that is expected to be exacerbated by climate change. The authors discuss the usefulness of the Gwangdong Reservoir Drought Management Model (GRDM2), which was developed in a previous study, and built on the basis of the adaptation mechanism, specifying the relationship between external disturbances (or future scenarios), system components pertaining to adaptation capacity, and vulnerability. The authors derive a total of 48 future scenarios, which consist of combinations of 6 future inflow scenarios and 8 future water requirement scenarios, of the Gwangdong reservoir drought management system. They then estimate the damage cost due to water scarcity in the dry season until the 2050s after feeding data in each scenario into GRDM2. The simulation reveals that extensive damage due to water scarcity may occur from the 2020s, and catastrophes, with damage four times greater than in the 2009 water scarcity accident, may occur in the 2050s. Assembling those results together, the authors conclude that GRDM2 is useful to measure the magnitude of climate change vulnerability, focusing on damage caused by water scarcity during the dry season. It is finally stated that to well prepare for climate change, engineers should investigate a suitable combination of available solutions, and at the same time perceive the threats that are attributed to high uncertainty.