Heavy rainfalls and floods, waterlogging triggered by rainstorms are one of the most serious natural disasters in Ningxia. This paper constructs an integrated rainstorm hazard risk warning model in Ningxia to effectively predict the risk of heavy rainfall and issue risk warnings in advance, by using the Analytic Hierarchy Process (AHP) and Delphi method, and considering four factors including hazard, exposure, vulnerability, and disaster mitigation capacity, the model incorporates 14 evaluation indicators such as population, economy, elevation, and vegetation etc. in Ningxia. Combined with GIS technology, a rainstorm event simulation was conducted. The results show that the model comprehensively and objectively reflected integrated risk distribution during rainstorms. The analysis of the rainstorm on July 10, 2022 indicated that the regions with the highest hazard were Jinfeng District and Xixia District of Yinchuan, Litong District of Wuzhong, Qingtongxia County, eastern Yanchi County, and Yuanzhou District of Guyuan; the highest exposure was in Yinchuan; the highest vulnerability was in western Qingtongxia, Tongxin County, Haiyuan County, Xiji County, and Pengyang County; the weakest disaster mitigation capacity was in Haiyuan County, and the highest integrated risk areas were Jinfeng District of Yinchuan, Litong District of Wuzhong, Haiyuan and Xiji County. Integrating the model with smart grid forecasting, the integrated rainstorm hazard risk can be calculated, which provides scientific basis for precise prevention in practical operations.

Recently, the droughts attack frequently in the Yangtze River basin, resulting in more and more loss. To further improve regional drought risk management and drought resistance capabilities, it is of great significance to conduct research on the spatio-temporal evolution characteristics of drought in typical drought-prone areas. “Heng-Shao-Lou drought corridor” in Hunan Province is a region with most severe droughts, the standardized precipitation index (SPI) dataset based on monthly precipitation data from 33 meteorological stations in this area from 1971 to 2022 is constructed. Citing the case of Shaoyang County, run theory is applied to integrate drought events, and Gumbel-Copula is adopted to construct the joint distribution function of drought duration and severity, then the joint return periods of drought are calculated and the method is extended to the whole study area. On the basis of it, the classification standard of drought grades is established, and the spatial distribution characteristics of drought probability for each level in the whole study area are analyzed. The results show that the peaks of theoretical joint return period of drought duration and severity for the type Ⅰ and type Ⅱ in Shaoyang County are around 97 a and 27 a, respectively, which indicates that the probability of drought events with long duration and high severity is very small and far lower than that of drought events with long duration or high severity, it is a common feature of drought events in research area. Furthermore, the combination of drought duration and severity joint distribution can effectively avoid segmentation of the whole drought event when drought grades are identified by a single variable, and can evaluate the complexity and large-scale impact of drought more accurately. In the past 52 years, the slight drought occurs most frequently in western region of the “Heng-Shao-Lou drought corridor”, while the frequency of severe or extreme drought is low. Extreme drought mainly distributes in Shaoyang County, Shaodong County and Shuangfeng County.

In recent years, Ningxia relies on unique natural resources to develop vigorously starry sky tourism industry, but the starry sky tourism is greatly affected by meteorological conditions. Based on the meteorological observation data at 25 weather stations of Ningxia, reanalysis data from European Centre for Medium-Range Weather Forecasts and radiance data of satellite from National Oceanic and Atmospheric Administration, the composite evaluation model of climate resources suitability of starry sky tourism in Ningxia is established from five aspects, such as cloud cover, light pollution, visibility, seeing and human body comfort degree, and the climate suitability of starry sky tourism in Ningxia is evaluated in different seasons. The results show that the starry sky tourism is suitable or very suitable in most areas of Ningxia all year round, while the suitability in urban area of cities (counties and districts) is relatively lower. The very suitable area to starry sky tourism is the largest in summer, and mostly in the plain area, followed by autumn and winter, and that is the smallest in spring.

Based on meteorology observation data and ECMWF numerical prediction products in winter 2016, a dynamically multivariate stepwise regression model was established for visibility prediction in Beijing by selecting some possible impact factors (water vapor, dynamic and thermodynamic factors and so on) as independent variables. Visibility was divided into three levels, namely visibility lower than 1 km, from 1 to 10 km (low visibility levels) and higher than or equal to 10 km, and the relevant forecast effect evaluation was conducted from the views of regional average, spatial distribution and cases analysis, respectively. The model had certain stable forecast capability for visibility and its change trend. The threat score (TS) of forecasted visibility greater than and equal to 10 km was largest (64.2%) , followed by the visibility of 1-10 km (53.1%), and the TS of visibility lower than 1 km was smallest (51.3%). The forecasting was better in plain areas than mountain areas for the lower two grades visibility, showing the decline distribution from the northeast to the southwest. On the contrary, the forecast capability of visibility more  than 10 km increased from the northeast to the southwest. Besides, forecasts of three cases also confirmed that this model had a relatively good forecasting ability of persistent fog-haze episodes occurring in Beijing.