This work analyzed the spatial and temporal variations of the extreme precipitation over China during the period 1982 to 2019, based on GPCC data. Meanwhile, the spatially clustering characteristic of China is evaluated based on the trends of summer precipitation through K-means. This is the first to clustering based on the trend of summer precipitation. The results indicated that the spatial distribution of MK trends for the summer precipitation indices over China during 1982 ~ 2019 shows increasing and decreasing trends in different regions. The extreme precipitation has been found mainly in Pearl River Basin, Southeastern River Basin, Huaihe River Basin, and the lower reaches of the Yangtze River. The risk of floods in SERB (the Southeastern River Basin), especially those caused by short-term heavy precipitation, may increase in recent decades. Four clusters are identified through K-means, which can be named as stable (59%), extreme wetter (5%), dryer (19%), and wetter (17%) zones. Combining the spatial distribution of the multi-year average of precipitation indicators and four clusters, the 'wet to wetter and dry to dryer' is found in China summer precipitation.

The Changsha region was an important place in China during the heyday of lacquerwares, from the Warring States Period to the Western Han Dynasty (476 bc – ad 9), when lacquerwares were used with varied styles and beautiful ornamentations. However, the process used to make lacquerware was previously unknown. By analysing samples of fragments of lacquerware found in the Changsha region dating back to between the Mid‐Warring States Period and the Mid‐Western Han Dynasty (390–87 bc), this paper demonstrates the varied constitution of the ground layer by analysing the features of the technique using non‐destructive methods. It also shows that the use of potassium alum, gypsum, carbon and brochantite as fillers in the ground layer can be dated back to the Mid‐Warring States Period. Furthermore, a comparison of techniques for ground layers from the Changsha region and other areas in China during this period is proposed on this basis.