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Droughts are increasing in frequency and intensity as the global climate changes. Risk assessment for agricultural drought disasters is an important approach for disaster prevention and mitigation. Based on the formation mechanism of natural disaster risk, the index system model of agricultural drought risk assessment in North China was constructed, and the robustness of the established risk assessment model was tested by using the internal test method. Then based on the characteristics of agricultural drought risk formation in North China, the paper proposes corresponding risk prevention recommendations. The conclusions were as follows: when adjusting the indices and methods in the risk assessment model, the range of changes in the agricultural drought risk ranking for each city was mostly 1-2.5 places, and the model was relatively robust. With the exception of Beijing and Tianjin, which had the highest disaster prevention and mitigation capacity, central and northern China had the highest agricultural drought risk, which was previously linked to the high risk and vulnerability of these regions. The agricultural drought risk in northern Henan and southern Shandong is low, mainly due to the low risk. The 34 cities in North China can be divided into 6 agricultural drought risk clusters, which are not dispersed in space and cross-city distribution, and have good aggregation. Cluster 4, located in the northernmost mountainous areas, has the highest risk of drought, which is associated with high environmental vulnerability and low capacity for disaster prevention and mitigation, so agricultural areas should be reduced and agricultural input should be increased. Clusters 2, 5 and 6, located in the central and southern regions, have higher grain acreage and yields due to drought, so agricultural drought risk can be further reduced by increasing agricultural input and improving irrigation guarantee rate. [ABSTRACT FROM AUTHOR]

With the promotion of government affairs data transformation in Zhejiang Province, Zhejiang government affairs Ding Talk（referred to as “Ding Talk”）, as the office platform of government affairs system, is widely used in the province. The early warning information service application of the emergency early warning information release system（referred to as the “emergency system”） is carried out based on Ding Talk. The government realizes the early warning information service that can directly reach the government personnel, further expands the coverage of the early warning information of the emergency system, and improves the service efficiency of meteorological disaster prevention and reduction.This paper analyzed the existing functional framework of the emergency system in Zhejiang Province,and focused on the application research of various information service channels of Ding Talk,which is connected to the emergency system.In addition,we developed an online early warning service applet on the Ding Talk to realize real-time viewing of current effective early warnings.Ding Talk has highlighted its good business application ability and development prospects in developing early warning information services. [ABSTRACT FROM AUTHOR]

The annual mean latitude of the life history maximum intensity (LMI) of tropical cyclones has shifted poleward in the major tropical cyclone basins around the globe, particularly in the Northwest Pacific (WNP), which is changing the statistical conclusions about storm surge in the ocean and affecting the determination of the tidal level criteria for fortification of the port area. In this paper, the two-dimensional hydrodynamic model MIKE21 and the Holland typhoon model are applied to develop a coupled astronomical tide-storm surge model to simulate the storm surge during Typhoon In-Fa. Three scenarios are set up to move the track of Typhoon In-Fa northward and analyze its impact on the storm surge in the Yellow Sea and the Bohai Sea. It is preliminarily concluded that, when the typhoon track moves northward by 3, the overall increase of storm surge height in the Bohai Sea reaches 17% and the storm surge along the coast from Lianyungang to Qidongjiao withina water depth of 30mincreases by 32%, etc. It can be used as a reference for coastal disaster prevention and mitigation and the determination of the tide level fortification standard in port areas. [ABSTRACT FROM AUTHOR]

The cultivation of apples plays an important role in China's fruit production. Climate change has brought about more frequent and severe drought and waterlogging disasters, which have negatively impacted apple yield quantity and quality. Through the summary of previous research studies done on the impact of drought and waterlogging disasters and its effect on apple production, methods for disaster prevention and mitigation can be provided to reduce the impact of these disasters to the industry. In this paper, the methods of classification and systematic analysis combined with studying actual disaster cases were used to review the latest research into the effects of droughts and waterlogging disasters on apple production in China and identify the next steps for future research and development into this subject. The intensity and impacts of droughts and waterlogging disasters on apple production are determined by weather, regional climate, topography, soil composition, and several other factors. Adopting the morphological indicators to study these disasters, most existing research into this area only focuses on meteorological factors and rarely consider agrometeorological factors such as soil composition, current crop conditions, and more. The distribution of apple drought disasters in China decreases from north to south. The prevention measures of apple drought and waterlogging included irrigation, strengthening orchard soil management, implementing the integration of soil and fertilizer, etc. More of the current research done into this subject takes place in the Northern parts of China and often lack the necessary information to be put into use in disaster monitoring and early warning applications. In the future, research into apple droughts and waterlogging disasters should focus on increasing in orchard observation data collection, constructing a disaster risk monitoring and early warning model, and implementing the model into apple growing. [ABSTRACT FROM AUTHOR]

The alluvial river flooding problem in Inner Mongolia is prominent along the upper reaches of the Yellow River. Studying the scour and silting evolution of the river and the response mechanism of the floods can provide technical support for flood prevention and disaster mitigation in this river section. According to data on ice flood and scour and silting evolution, this paper produces the response relationship between a scour and silting evolution characteristics indicator and an ice flood condition change representation indicator based on formulaic calculations and related analyses. The results show that bankfull discharge, a characteristic indicator of river scour and siltation evolution, is closely related to the characterization indicators for ice flood sub-ice flow capacity and trough water storage increment. The under-ice flow capacity is about 1/5 that of bankfull discharge, and it decreases as bankfull discharge decreases. In addition, the channel detention increment increases as bankfull discharge decreases. The safety flow capacity in the main channel for ice flood control should not be less than 2 000 m³/s, and the increment in water storage should be kept below 1.4 billion m³ in the reach. The preliminary results can serve as a major guide for ice flood control in Inner Mongolian reaches. [ABSTRACT FROM AUTHOR]

The pre-failure evolution of landslides is of great value for the analysis of landslide triggering factors and post-disaster stability assessment. At present, optical images are commonly employed to ana⁃ lyze the pre-failure evolution, but it is well-known that their data availability could be highly limited due to the presence of clouds. With the advance in radar remote sensing and interferometric synthetic aperture radar(InSAR), it could provide a new technical approach for landslide pre-failure detection. In this paper, the 2018 Nanyu landslide in Gansu Province is utilized to demonstrate the capability of InSAR to trace its pre-failure surface displacements using European Space Agency’s Sentinel-1 radar data with a temporal interval of 12 days in different tracks. The results show that the landslide began to deform in June of 2017, and the maximum cumulative deformation reached up to 77 mm in the 13 months before the occurrence of the landslide. The time series InSAR derive displacements and the rainfall data is consistent, suggesting that the rainfall should be one of the triggering factors for the landslide. The study demonstrates the potential of radar interferometry for landslide detection, which can provide insights on landslide triggering factors, landslide disaster prevention and mitigation, and even landslide monitoring and early warning work in the future. [ABSTRACT FROM AUTHOR]

Drought has become a problem that is universally faced by global terrestrial ecosystems. Northeast China is dominated by a temperate monsoon climate and located in an area sensitive to global climate changes, and one of the main impacts of climate changes in Northeast China is manifested as drought in growing seasons. The drought area has a gradual increase trend, and drought has become the main agro-meteorological disaster in this region which is also the main maize planting area in China. Drought normalization seriously restricts the stable development of maize production in Northeast China. So in this paper, we took spring maize in Liaoning Province as an example and made clear the drought variation characteristics in different growth stages by using the data of MODIS, FY-3A, relative soil moisture and growth stages and the methods of RS, GIS and statistical analysis. Then we analyzed the correlation between multi-time scale remote sensing indexes and relative soil moisture in different soil depth, and established the remote sensing monitoring index set and models of relative soil moisture for each growth stage and soil depth. The accuracy of the monitoring models was verified and the application research of monitoring the drought of spring maize in Liaoning Province was studied. The results showed that: From 1993 to 2012, drought occurred in each growth stage of spring maize in Liaoning Province and the highly frequent drought occurred in the period from 1999 to 2002. The drought grade in each year was mainly light drought, and the drought was the most serious at milk stage, followed by heading stage. There was no significant correlation between the monitoring indexes and relative soil moisture at sowing and emergence stage, but there was a significant or extremely significant correlation between them at three-leaf and maturity stage. The monitoring index LSWI (land surface water index) had a strong ability to monitor relative soil moisture, followed by WI (water index). Multi-index coordination could improve the monitoring ability of relative soil moisture by remote sensing means, and the monitoring ability at 10-day scale was generally higher than that at 5-day scale and 20-day scale. Based on the monitoring models of soil relative humidity, the drought condition of partial growth stages and soil depth from 2001 to 2004 was monitored. The overall monitoring accuracy was 73.32%, in which the monitoring accuracy of jointing and three-leaf stage was more than 85%. The dynamic monitoring of drought grades in different growth stages in 2000 was realized. The monitoring results were consistent with the agro-meteorological observation records in terms of the growth stages and space. This study would be very significant to improve the capacity of disaster prevention and mitigation by monitoring spring maize accurately and synchronously on a large range. [ABSTRACT FROM AUTHOR]