Analyzing exposure risk and change characteristics of wind-driven rain in China under future climate scenarios

Abstract

Wind-driven rain (WDR) is the primary source of building moisture, and it has a direct impact on the durability and thermal performance of building envelopes. To suppress the impact of WDR on buildings under climate change, this study analyzed three representative concentration pathways (RCP) scenarios (RCP2.6, RCP4.5, and RCP8.5) based on the climate data of Meteonorm and assesses China's forecasted WDR for the next 80 years. The WDR exposure maps and the WDR increase maps of China's three future emission scenarios in 2050, 2080, and 2100 were plotted, and the rate of increase of WDR was calculated. A total of ten representative cities in China were selected based on their WDR exposure. Using the ASHRAE 160-2021 standard, WDR patterns of 16 orientations of building facades in the ten selected cities in 2050, 2080, and 2100 under three future climate scenarios were obtained. The results show that China's overall WDR exposure will increase under the three future climate scenarios, with the increase under the RCP4.5 scenario being the largest. From a regional perspective, southeastern China is exposed to severe WDR in current scenarios and may also be exposed to the same in future scenarios; the absolute increase of WDR is also the largest. There are certain differences in WDR exposure and increase of WDR exposure in cities in different climate zones in China, and the increase in coastal areas is significantly greater than that in inland areas. Particularly, in Shanghai, the exposure of WDR evidently increases both in summer and winter.