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Sustainable management of blue and green water resources is vital for the stability and sustainability of watershed ecosystems. Although there has been extensive attention to blue water (BW) which is closely related to human beings, the relevance of green water (GW) for ecosystem security is typically disregarded in water resource evaluations. Specifically, there is a scarcity of comprehensive study on the detection and attribution of variation of blue and green water in the Dongjiang River Basin (DRB), an important source for regional water supply in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) of China. Here we assess the variations of BW and GW scarcity, quantify the impacts of climate change and land use change on BW and GW in DRB using a multi-water-flux calibrated Soil and Water Assessment Tool (SWAT). Results show that BW and green water storage (GWS) in DRB increased slowly with a rate of 0.14 and 0.015 mm a-1, respectively, while green water flow (GWF) decreased significantly at a rate of -0.21 mm a-1. The degree of BW and GW scarcity in DRB is low, and the per capita water resources in more than 80 % of DRB exceed 1700 m3 capita-1 a-1. Attribution results show that 88.0 %, 88.5 %, and 39.4 % of changes in BW , GWF , and GW S results from climate change, respectively. Both climate change and land use change have decrease BW , while climate change (land use change) decrease (increase) GW F in DRB. These findings can guide to optimize the allocation of blue and green water resources between upper reach and lower reach areas in DRB and further improve the understanding of blue and green water evolution patterns in humid regions. [ABSTRACT FROM AUTHOR]

Based on hourly precipitation data from 28 rainfall stations in the Pearl River Delta (PRD) region from 2001 to 2012, the accuracy of CMORPH, GPM and ERA5 is evaluated in the PRD on the annual, monthly and daily time scales by calculating 6 statistical metrics and exploring the frequency of different precipitation events. The results show that: (1) Compared with the three time scales of year, month and day, three products showed a highly positive correlation with the measured rainfall station on the monthly scale, but the correlation is weak on the annual and daily scales. (2) At the daily scale, all three precipitation products perform worse in the flood season than in the non-flood season. They are less accurate in detecting precipitation events in dry months than in other months, but the false alarm rate is higher in autumn and winter, and they all have a higher false alarm rate for stations near the coast than for inland stations. (3) In contrast, GPM can more accurately reflect the spatio- temporal trend and spatial distribution characteristics of precipitation in the PRD region. (4) Both CMORPH and GPM show high capacity to estimate various types of precipitation events, which can well reflect the contribution of the measured data to different types of precipitation events. Overall, GPM can best reflect the actual situation in the PRD region among the three products. [ABSTRACT FROM AUTHOR]

The unprecedented 2022 Yangtze River Basin (YRB) heatwave is a threat to human society and natural ecology, so the understanding of its underlying drivers is critical to regional climate adaptation and resilience. Here we conducted a multi‐method attribution analysis on the contribution of atmospheric circulation change and anthropogenic impacts to the occurrence probability and intensity of this extreme heatwave. Based on the nonstationary statistical analysis, the 2022 YRB heatwave is a 1‐in‐900‐year event and a 1‐in‐110‐year event with and without considering the 2022 YRB heatwave in the fitting, respectively. The large‐scale meteorological condition analysis shows that the 2022 YRB heatwave is featured with an anomalous high‐pressure system that favors a hot and dry atmospheric column, overlaid by anomalous subsidence and clear skies which leads to warming and greater solar heating. The ensemble constructed circulation analogue analyses show that the circulation anomaly fails to explain the observed 2022 YRB SAT anomalies fully. Specifically, 46% (0.132 ± 0.027°C decade−1) of the observed SAT trend during 1979–2022 (0.290 ± 0.048°C decade−1) is caused by anthropogenic warming and the associated thermodynamic feedback, while the remaining 54% (0.157 ± 0.038°C decade−1) of the trend is caused by changes in the large‐scale atmospheric circulation. Our findings on changes in atmospheric circulation patterns associated with YRB heatwave and anthropogenic contributions to YRB heatwave could provide valuable information for climate adaptation and mitigation strategies in the context of a warming climate. Plain Language Summary: Heatwaves are major climate extremes in the context of global warming, which have inverse effects on human health, food and energy production, and ecosystems. The 2022 heatwave in the Yangtze River Basin (YRB) sets a new record in observational history with its extreme intensity, long duration, and widespread affected areas. The 2022 YRB heatwave is too exceptional to be possible without anthropogenic warming, which is a 1‐in‐900‐year event and a 1‐in‐110‐year event, respectively, with and without considering it in the nonstationary statistical fitting. An anomalous and prolonged high‐pressure system predominated the evolution of the 2022 YRB heatwave, which favors anomalous subsidence and clear skies, leading to hot and dry atmospheric conditions. Next, we applied an ensemble circulation constructed analogue approach to separate the contributions of large‐scale circulation changes and anthropogenic warming in generating the 2022 heatwave. The results reveal that circulation dynamics can only partially explain the 2022 event. When historical changes are taken into account, the changes in large‐scale circulation and anthropogenic warming, respectively, can account for 54% and 46% of the observed summer surface air temperature anomalies in the YRB region. Key Points: The 2022 Yangtze River Basin (YRB) heatwave, linked to anomalous circulation backgrounds, set unprecedented records for surface air temperature (SAT)The atmospheric circulation anomalies alone cannot fully explain the SAT anomalies during the 2022 YRB heatwaveThe variation in atmospheric circulation and anthropogenic warming contributed nearly equally to the historical SAT trend of YRB [ABSTRACT FROM AUTHOR]

Multi‐mode mechanoluminescence (ML) materials are have applications such as anti‐counterfeiting, stress sensing, and information security. There is limited general consensuses on the luminescent mechanisms, even though exploring ML mechanism based on defects has shown significance in further studies exploring both ML materials design and application. Here, a deep‐red to near‐infrared (NIR) ML material is reported in a Mn2+‐activated double perovskite‐type compound (CaZnGe2O6: Mn2+). The abundant lattice sites within the crystal structure have enabled Mn2+ doping and defects. Two different photoluminescence (PL) emission bands peaked at 536 and 676 nm from 4T1(4G)→6A1(6S) are observed, which are attributed to the substitution of Zn2+ and Ca2+ sites by Mn2+, respectively. Hence, tunable emissions from green to red are realized in single Mn2+ doping, which can be further regulated by varying the Mn2+ concentration. Electrons and holes are captured by cation and anion defects (VZn′′$V_{{\mathrm{Zn}}}^{\prime \prime }$ and VCa′′$V_{{\mathrm{Ca}}}^{\prime \prime }$, VO••$V_{\mathrm{O}}^{ \bullet \bullet }$, vacancy of Zn, Ca and O ions), followed by the combination of such carriers to transfer energy to the Mn2+ 3d states to produce ML/persistent luminescence (PersL) under mechanical/thermal stimuli. Proof‐of‐concept applications in multi‐mode anti‐counterfeiting, temperature sensing, and X‐ray imaging fields are demonstrated. These results will deepen the understanding of single Mn2+‐doped multi‐stimulus‐responsive ML materials, inspiring the development of more high‐performance ML phosphors for practical applications. [ABSTRACT FROM AUTHOR]