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This study explored the interannual relationship between autumn Arctic sea ice concentration (SIC) and the subsequent summer precipitation over East Asia (EASP). Since the late‐1990s, the declining SIC in the Kara–Laptev Seas has been significantly correlated with EASP as well as extremely positive anomalies in northern China and intensely negative anomalies in central‐eastern East Asia. However, there was a weak correlation between autumn SIC and EASP before the late‐1990s. Furthermore, the anomalous precipitation pattern in summer and its connection with autumn SIC variability can be explained by the seasonal persistence of continental processes (snow depth and soil moisture) into the spring. In particular, a decreasing SIC was connected with simultaneously positive and negative precipitation anomalies over northeastern China and the Siberian region, respectively, since the late‐1990s and tends to produce corresponding soil moisture anomalies over the Eurasian continent. Declining SIC also favours increased snow depth anomalies in winter over northeastern East Asia. These anomalous signals of surface processes can persist from winter into the subsequent spring, making the connection between the autumn SIC and EASP possible. The Community Earth System Model Large Ensemble simulations further verified these physical processes. More detailed mechanism for this relationship needs to be stressed in further work by numerical simulations. The results have important implications for extending the seasonal prediction validity of EASP. Moreover, before the late‐1990s, SIC‐related circulation anomalies shifted westward and northward as negative precipitation anomalies developed over west Siberia in autumn. As a result, anomalous dry soil conditions in Siberia persisted into the subsequent spring and then led to wetter‐than‐normal conditions through locally negative soil moisture–precipitation feedback before the late‐1990s. [ABSTRACT FROM AUTHOR]

Spatially downscaling satellite precipitation products have been performed on annual and monthly precipitation. Accurate downscaling on daily precipitation remains a challenge due to the limitation of the downscaling assumption, the large spatial discontinuity of daily precipitation, and the relatively poor quality of satellite‐derived daily precipitation product. In this study, an integrated downscaling‐fusion framework was proposed and used to downscale satellite‐derived daily precipitation. First, a spatio‐temporal downscaling scheme is applied to produce preliminary downscaled daily precipitation. The accuracy of the derived preliminary results is then boosted by merging with daily gauge observations using an ensemble fusion method. The performance of the proposed framework was tested and evaluated by downscaling the Integrated Multi‐satellite Retrievals for Global Precipitation Measurement (IMERG) daily precipitation data from 0.1 to 0.01° over eastern and central China for the period of 2015–2016. The results showed that (a) the downscaling scheme accurately mapped the spatio‐temporal variation in daily precipitation, and the preliminary downscaled results perfectly maintained the accuracy of the original IMERG data; (b) the fused results were much more accurate than the original IMERG data, decreasing the root‐mean‐square errors (RMSEs) by 22, 10, and 18% at daily, monthly, and annual timescales, respectively, for the whole period; and (c) the fused daily precipitation data considerably strengthened the detection of rain/no rain area compared with the original IMERG daily precipitation data, with a 17% reduction in the inconsistency index. An integrated downscaling‐fusion framework has been developed for satellite‐derived daily precipitation products, aiming to generate high‐resolution daily precipitation data with further improved quality. The results showed that (a) compared with the original IMERG data, the fused results, including daily, monthly, and annual precipitation, not only exhibited much more spatial details, but also had significant accuracy improvements; and (b) the fused daily precipitation data considerably strengthened the detection of rain/no rain area compared with the original IMERG daily precipitation data. [ABSTRACT FROM AUTHOR]

Considering the 'Green Great Wall' project and future climate change, the vegetation in the Northwest Hetao Plain (NWHP) of China is expected to undergo considerable changes. In this study, the climatic response to prescribed changes in vegetation is investigated using the Weather Research and Forecasting model. When the vegetation is changed from 'bare or sparsely vegetated' category to 'grassland' in the NWHP, the climate shows both local and remote responses. Locally, the temperature increases in the winter but decreases in the summer. The precipitation level increases substantially in the summer while increases slightly in the winter, which is mainly caused by the increase in the amount of water-vapour and circulation adjustment. Additionally, atmospheric circulation anomalies also lead to remote circulation responses, including a decrease in precipitation over Central North China and an increase in precipitation over Central and South China. The results of this study bring to light the local and remote climatic responses to changes in vegetation in the NWHP using a state-of-the-art regional climate model. Copyright © 2012 Royal Meteorological Society [ABSTRACT FROM AUTHOR]