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The simultaneous occurrence of extreme weather events such as high temperature, low humidity and strong wind speed can cause devastating impacts on the fragile environment and vulnerable ecosystem in arid Northwest China (NW). However, few studies investigate the multivariate compound hot, dry and windy extremes in NW. In this study, we investigate the temporal and spatial variations of the warm‐season trivariate hot, dry and windy (HDW) and bivariate hot and dry (HD), dry and windy (DW), hot and windy (HW) extremes in NW. From 1960 to 2019, we observed more compound HD, DW, HW and HDW days in the hyper‐arid Xinjiang and west Gansu in NW. Simultaneously, DW days, HW days and HDW days consistently declined at rates of −0.48, −0.88 and −0.42 day·10a−1, except for a discernible increasing rate of 0.56 day·10a−1 in HD days. Notably, trends in four multivariate compound extremes all experienced pronounced reversals from a declining to increasing trend in the 1990s. The higher probability of compound HD, DW and HW extremes contributed to a higher probability of HDW in Xinjiang province. Ultimately driven by the significantly rising temperature (0.21°C·10a−1, p < 0.01), four compound extremes suggested increased probability with the largest increase in compound HW probability from 1960–1989 to 1990–2019. Both the rising trends in the occurrence and the increased probability of four compound extremes highlight intense risks of compound extreme weather over NW in recent decades. [ABSTRACT FROM AUTHOR]

It is demonstrated that palynomorphs can occur in fired ancient potsherds when the firing temperature was under 350°C. Pollen and phytoliths recovered from incompletely fired and fully fired potsherds (ca. 2700 yrs BP) from the Yanghai Tombs, Turpan, Xinjiang, NW China can be used as potential indicators for reconstructing past vegetation and corresponding climate in the area. The results show a higher rate of recovery of pollen and phytoliths from incompletely fired potsherds than from fully fired ones. Charred phytoliths recovered from both fully fired and incompletely fired potsherds prove that degree and condition of firing result in a permanent change in phytolith color. The palynological data, together with previous data of macrobotanical remains from the Yanghai Tombs, suggest that temperate vegetation and arid climatic conditions dominated in the area ca. 2700 yrs BP. [ABSTRACT FROM AUTHOR]