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The Ningxia Hui Autonomous Region of China (Ningxia), one of main agriculture areas in northwest China, has been severely affected by drought. Based on observed meteorological data, outputs of 20 global climate models and drought disaster data, future climate change and relevant drought hazard in the twenty-first century were projected in Ningxia, with the scenarios of RCP2.6 and RCP4.5; the risks of people, crop, and agriculture economy to drought disasters are quantitatively assessed, with the application of physical vulnerability curve models, probability distribution functions and Monte Carlo simulation method. It is found that the climate in Ningxia is likely to have a warming and wetting tendency in the twenty-first century. The extent of drought hazard is likely to increase. The increase rate is greater under RCP4.5 than that under RCP2.6. In general, the risks of population, crop, and agriculture to drought disasters are likely to increase in Ningxia in the twenty-first century. The magnitude of increase is likely to reach the greatest in the immediate term (2016–2035), followed by the increase in the medium term (2046–2065), and the long term (2081–2100). In comparison with RCP2.6, the drought disaster risks under the scenario of RCP4.5 are likely to increase further in three periods of the twenty-first century. The findings of this work have potential to provide data support for drought disaster risk management and support risk-based decision-making. [ABSTRACT FROM AUTHOR]

The start and duration of a drought are often not easy to define. The advance and onset are usually slow and the social and economic impacts can then extend over a long period. In this study, the Standardized Precipitation Index (SPI) was used to describe and compare droughts in different periods and regions under different climatic conditions. The importance of the index lies in its simplicity and in its ability to identify the beginning and end of a drought event. Thus it may be a useful tool for drought contingency planning. This paper examines the SPI by evaluating its application using historical precipitation data from nine weather stations in China. Different time series data covering the period 1980 to 2011 and for differing timescales of 3, 9 and 24 months were used. The results underline the potential of the SPI to inform drought alerts and forecasting efforts as part of a drought contingency planning strategy. [ABSTRACT FROM AUTHOR]

Drought is one of the major natural disasters in northern China. Therefore, monitoring and analyzing the changes of drought indices can provide scientific evidence for disaster assessment and for instituting policies for disaster prevention and mitigation. In this work, we used the gridded precipitation data set of a semi-arid steppe region in the Inner Mongolian Plateau from 1962 to 2017 to calculated the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI). By comparing the spatiotemporal distribution of the two indices with the historical drought records, we found that the SPI was more suitable for the drought description in the study area. Based on this, we calculate the SPI at different time scales (annual and seasonal), then depict the spatiotemporal variation of drought during the past 56 years by analyzing the frequency of drought events, drought frequency, and the station frequency ratio. The results indicate that in recent years, the degree of drought in the study area has increased, and the south-central regions are the highest occurrence area for different types of drought events. In addition, light drought occurs mostly in the autumn and is mainly distributed in the central and southern parts of the study area. The most extreme drought events often occur in the summer, and the highest frequency area is located in the western part of the study area. Large-scale light drought occurred in all seasons in the 1990s, while the domain moderate drought and the domain extreme drought occurred in the summers of 2001 and 2010, respectively. [ABSTRACT FROM AUTHOR]

Debris-flow disasters occurred frequently after the Mw 8.0 Wenchuan earthquake on 12 May 2008 in Sichuan Province, China. Based on historical accounts of debris-flow disaster events, it found that debris flow occurrence is closely related to the impact of earthquakes and droughts, because earthquake-drought activities can increase the loose solid materials, which can transform into debris flows under the effect of rainstorms. Based on the analysis of historical earthquake activity (frequency, magnitude and location), drought indexes and the trend of climate change (amount of rainfall), a prediction method was established, and the regional debris flow susceptibility was predicted. Furthermore, in a debris flow-susceptible site, effective warning and monitoring are essential not only from an economic point of view but are also considered as a frontline approach to alleviate hazards. The advantages of the prediction and early monitoring include (1) the acquired results being sent to the central government for policy making; (2) lives and property in mountainous areas can be protected, such as the 570 residents in the Aizi valley, who evacuated successfully before debris flows in 2012; (3) guiding the government to identify the areas of disasters and the preparation for disaster prevention and mitigation, such as predicting disasters in high-risk areas in the period 2012–2017, helping the government to recognize the development trend of disasters; (4) the quantitative prediction of regional debris-flow susceptibility, such as after the Wenchuan earthquake, can promote scientific and sustainable development and socioeconomic planning in earthquake-struck areas. [ABSTRACT FROM AUTHOR]