Search

This study investigated future projections of extreme precipitation (PR) over the Korean Peninsula (KP) under global warming levels of 1.5 °C and 2.0 °C (GWL 1.5 °C and 2.0 °C). The bias-corrected large ensemble of the Regional Climate Model (RCM) in the Coordinated Regional Climate Downscaling Experiment–East Asia Phase 2 was used. Under GWL 1.5 °C, the RCM multi-model ensemble (MME) predicted the extreme PR intensity (RX1day) to increase by 10.14% more than the mean PR of 4.69%. A regional difference was observed in the projection, with a larger increase over the northern KP (NKP) and southern KP (SKP) than central KP. Accordingly, the distribution of extreme PR was expected to shift with the right, and extreme events occurring once every 20 years over the SKP and NKP were expected to change to a reoccurrence of 12.56 years and 10.04 years, respectively. The mechanism of extreme PR was examined for cases from June to September. The expected increase in extreme PR per warming over the SKP and NKP was 5.64% °C−1 and 8.37% °C−1, respectively, which was close to the Clausius-Clapeyron scale (7.7% °C−1). This implies that increased moisture capability from the warming will affect the change in extreme PR. Other possible factors were investigated and the RCM MME predicted vertical instability over East Asia to continue, and moisture flux and convergence around the KP to be intensified. Meanwhile, under GWL 2.0 °C, mean PR and extreme PR were projected to increase more than under GWL 1.5 °C. [ABSTRACT FROM AUTHOR]

The adverse impacts of extreme heat on human health when a concurrent daytime and nighttime heatwave (CDNHW) occurs are greater than when daytime or nighttime heatwaves occur individually, because of the reduced recovery time from heat exposure. This study projects increases in CDNHW over the whole of East Asia under two Representative Concentration Pathway scenarios (RCP2.6 and RCP8.5) and two Shared Socioeconomic Pathway scenarios (SSP1‐2.6 and SSP5‐8.5). The daily maximum and minimum temperatures, which are used to define a CDNHW, are calculated of 3‐hourly temperatures of 25 km horizontal resolution produced by 12 general circulation model and regional climate model chains participating in the Coordinated Regional Climate Downscaling Experiment East Asia phase 2 project. In Historical simulation (1981–2005), occurrence period and occurrence rate of CDNHW from April to September area‐averaged in East Asia are 10.9 days and 0.9%, respectively. In projections for the future (2071–2100), occurrence period and occurrence rate of CDNHW will be 3 weeks and 3.7% (RCP2.6), 2 months and 20.5% (RCP8.5), 2 months and 15.6% (SSP1‐2.6), and 3 months and 45.7% (SSP5‐8.5). In addition, it is expected that the CDNHW intensity will increase, and the spatial extent of CDNHW will be extended. Although a CDNHW lasting less than 3 days is the most common, the proportion of CDNHWs lasting more than 10 days, compared to the total CDNHW frequency, will increase to 1.2% (RCP2.6), 7.2% (RCP8.5), 6.1% (SSP1‐2.6), and 17.3% (SSP5‐8.5) from 0.2% (Historical). Both occurrence rate and intensity of CDNHW will increase to a relatively large extent in Indochina, East and West China, and India. If the current greenhouse gas emissions continue, East Asia will experience unprecedented heat stress because the frequency and intensity of CDNHWs, which rarely occur during present‐day, will increase significantly over all regions by the end of the 21st century. [ABSTRACT FROM AUTHOR]

Five regional climate models (RCMs)—CCLM, RegCM, HadGEM3‐RA, SNURCM and WRF—participating in the Coordinated Regional Climate Downscaling Experiment‐East Asia (CORDEX‐EA) Phase 2 project are evaluated for their ability to simulate spatiotemporal variability in Asian summer precipitation. For this purpose, two dynamical downscaling sets, experiments forced by ERA‐Interim reanalysis data (reproduction experiment) and historical data from three Coupled Model Intercomparison Project 5 (CMIP5) general circulation models (GCMs) (historical experiment) are analysed. The horizontal resolution of the downscaled results is 25 km, and the analysis period is from 1981 to 2005 (25 years). The RCMs show reasonable performance in simulating the spatial and temporal characteristics of summer precipitation in CORDEX‐EA Phase 2 domain. To assess spatiotemporal patterns in Asian precipitation, cyclostationary empirical orthogonal function (CSEOF) analysis is used. In the first mode representing seasonal variations, the model ensemble results of both the reproduction experiment (Rep_ENS) and the historical experiment (His_ENS) simulate the peak times, location of precipitation and progression of the monsoons in Asia reasonably. Their features are greatly influenced by the moisture flux, indicating that the relation between precipitation and 850 hPa moisture flux is depicted well by RCM ensembles. In the second mode, which represents intraseasonal variations, the Rep_ENS depicts the western North Pacific summer monsoon break (WNPSM break) phenomenon similar to the observation. Although the His_ENS simulates the WNPSM break later than the observation, it does present the intraseasonal variation in the East Asian summer monsoon region. Based on these results, the five RCM ensemble results show the ability to capture spatiotemporal characteristics of summer precipitation in CORDEX‐EA Phase 2 domain, as well as added value from dynamical downscaling. [ABSTRACT FROM AUTHOR]

Wind power, which is the fastest–growing renewable energy source, is directly influenced by weather or climate conditions. This study examined the recent changes and future projections under different carbon emission levels in the wind power potential (Wpot) over East Asia using the ERA5 datasets and high–resolution multiple regional climate models (RCMs). Because wind conditions are constantly changing, we employed the wind velocity range–based approach for estimating the Wpot using the shortest time interval data available, which is the three–hourly wind velocity. Seasonal Wpot climatology of area–averaged Wpot over East Asia was the highest in spring. The average Wpot showed the highest values in northern China and southern Mongolia throughout all seasons, while recent changes in the Wpot over East Asia were characterized by overall increases in spring, autumn, and winter, but a decrease in summer. However, there were large regional variabilities. Northern China and southern Mongolia are expected to remain significant regions with high Wpot in the future. This is due to the large contribution of the frequency of optimal wind conditions, ranging from 12 m s−1 to 25 m s−1, to the Wpot in these regions, both currently and in the future. The average future Wpot in East Asia is expected to show no significant changes in both the low and the highest carbon emission scenarios compared to the present. However, it is projected that regional disparities in the Wpot will increase in a scenario with enhanced emission by the end of the 21st century. [Display omitted] • Seasonal Wpot climatology of area–averaged Wpot over East Asia was the highest in the spring, and the rest of the seasons were similar. • Northern China and southern Mongolia are expected to remain significant regions with high Wpot in the future due to the relatively significant contribution of 12 m s−1 to 25 m s−1 wind velocity range, which is good for wind power generation, to the future Wpot in these regions. • The average future Wpot in East Asia is expected to show no significant changes compared to the present, but it is projected that regional disparities in the Wpot will increase in a scenario with enhanced emission by the end of the 21st century. [ABSTRACT FROM AUTHOR]

Heavily industrialized East Asia, with its high greenhouse gas emissions, must inevitably increase renewable energy production to achieve the goals of the Paris Agreement. Photovoltaics (PV), a widely utilized renewable energy source, is directly affected by the weather and climate. This study conducted the first analysis of current and future PV potential (PVpot) changes over East Asia using the ERA5 reanalysis and multiple high-resolution regional climate model simulations. The recent PVpot over East Asia did not exhibit any notable changes, but the future PVpot of the multi-model ensemble is predicted to decrease by −4.3% (winter) to −1.5% (summer) on average with excellent inter-model agreements. Results demonstrated that the widespread increase in near-surface air temperature causes the overall PVpot decrease (around −2.0%) over East Asia across all seasons. Interestingly, surface down-welling shortwave radiation increases in summer, offsetting temperature-induced PVpot decreases (by about 0.7%) while it declines in winter and spring, intensifying the warming-driven PVpot decrease (by approximately −1.4% to −2.3%). Further, the changes in the number of rainy days are associated with the changing patterns of surface down-welling shortwave radiation, indicating the importance of reliable projections of precipitation. Wind speed exerts a negligible effect on the future PVpot change. [Display omitted] [ABSTRACT FROM AUTHOR]