High-resolution ensemble projections and uncertainty assessment of regional climate change over China in CORDEX East Asia

Abstract

Abstract. An ensemble simulation of 5 regional climate models (RCMs) from the Coordinated Regional Downscaling Experiment in East Asia (CORDEX-East Asia) was evaluated and used for future regional climate change projection in China. Meanwhile, the contributions of model uncertainty and internal variability are identified. The RCMs simulated both the historical climate (1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008) likely to increase in most of the simulation region, except the Tibetan Plateau which decreases -7.8%. Compare with the similar seasonal temperature changes with the driving global climate model (GCM), the seasonal precipitation change shows significant inter-RCM difference and has larger magnitude and variability than driving GCM. The model uncertainty for future temperature projection is clearly dominant over the northeast, northwest China and Tibetan Plateau, reaching up to 70%, and it contribute about 40% of the total uncertainty over north and south China. For precipitation, the internal 20 variability is dominant over most regions except for the Tibetan Plateau which the model uncertainties reach up to 60%. In addition, the model uncertainty increases with prediction lead time over all subregions.

Survival of the Qaidam Mega-Lake System under Mid-Pliocene Climates and its Restoration under Future Climates

“…Table 2 presents estimates for mean annual changes in the water balance of the Qaidam basin due to climate changes with respect to present conditions. The first three rows (marked in red) indicate changes in q, P, and ΔS = P -ET for estimates of minimum and maximum changes in T. As conservative estimates, the minimum and maximum changes in air temperature were set to 1 K and 2 K, respectively, which can be used as estimates for the air temperature range representing both mid-Pliocene climates and those projected for the end of the 21st century (Burke et al, 2018;Gu et al, 2018;Hui et al, 2018).…”

“…Global climate change as projected for the future and its consequences for the regional climates of China (Burke et al, 2018;Gu et al, 2018;Hui et al, 2018) could lead to strengthening of the East Asian Summer Monsoon (Wang et al, 2008), which could also affect the Qaidam basin such that both specific humidity and precipitation would increase. This would then lead to continued recharge of groundwater reservoirs and, at a later stage, to rising lake levels or formation of new lakes.…”

“…Other lines of research could focus on dynamical downscaling of paleoclimate simulations for Pliocene time slices or global climate projections for the future. Both kind of data sets are, in general, spatially too coarse to fully resolve atmospheric processes like orographically induced precipitation or actual evapotranspiration in high mountain ranges (Gu et al, 2018), such that regional water balance computations based on coarse data would, most likely, come with high uncertainties. Thus, dynamical downscaling of global atmospheric data is regarded to be essential.…”

“…Moreover, a physically based explanation for the longterm existence of the mega-lake system under dry climate conditions is sought. Since the mid-Pliocene is often regarded as past analogue for modern climate changes (Zubakov and Borzenkova, 1988;Haywood et al, 2016), this study also intends to provide a rational basis for assessing environmental changes that might be caused by climate changes as projected in this region for the future (Burke et al, 2018;Gu et al, 2018;Hui et al, 2018).…”

Restoration Plan for Degraded Forest in The Democratic People’s Republic of Korea Considering Suitable Tree Species and Spatial Distribution

“…Therefore, this method can control the spatial scale with changing information within a grid. The 1 km and 12.5 km resolution scales were also chosen to agree with climate change scenarios generated by the Korea Meteorological Administration using HadGEM3-RA (Met Office, Devon, United Kingdom's) [37]. Agreement between climatic data and spatial scale satisfies the sustainable forest management plans in South Korea.…”