Characteristics and Variations of the East Asian Monsoon System and Its Impacts on Climate Disasters in China

Recent advances in studies of the structural characteristics and temporal-spatial variations of the East Asian monsoon （EAM） system and the impact of this system on severe climate disasters in China are reviewed. Previous studies have improved our understanding of the basic characteristics of horizontal and vertical structures and the annual cycle of the EAM system and the water vapor transports in the EAM region. Many studies have shown that the EAM system is a relatively independent subsystem of the Asian- Australian monsoon system, and that there exists an obvious quasi-biennial oscillation with a meridional tripole pattern distribution in the interannual variations of the EAM system. Further analyses of the basic physical processes, both internal and external, that influence the variability of the EAM system indicate that the EAM system may be viewed as an atmosphere-ocean-land coupled system, referred to the EAM climate system in this paper. Further, the paper discusses how the interaction and relationships among various components of this system can be described through the East Asia Pacific （EAP） teleconnection pattern and the teleconnection pattern of meridional upper-tropospheric wind anomalies along the westerly jet over East Asia. Such reasoning suggests that the occurrence of severe floods in the Yangtze and Hualhe River valleys and prolonged droughts in North China are linked, respectively~ to the background interannual and interdecadal variability of the EAM climate system. Besides, outstanding scientific issues related to the EAM system and its impact on climate disasters in China are also discussed.

Analysis of Main Climatic Disasters in Rice Production in Changsha and its Strategies

According to the meteorological data from National Basic Meteorological Station in Changsha in recent 43 years and statistics of occurrence time and intensity of main meteorological disasters for rice in Changsha in recent 13 years,a comparison was conducted to the meteorological situations between the first 30 years and the last 13 years.Results indicated that the main meteorological disasters in rice production in Changsha showed an increasing occurrence tendency of high temperature damage,drought and cold-dew wind,but a decreasing occurrence tendency of low temperature,late spring cold,dry and hot wind,gale,hail,flood,cloudy and drizzly day.In the end,some corresponding strategies for preventing and reducing meteorological disasters in rice production were put forward.

The first high spatial resolution multi-scale daily SPI and SPEI raster dataset for drought monitoring and evaluating over China from 1979 to 2018

Standardized Precipitation Index(SPI)and Standardized Precipitation Evapotranspiration Index(SPEI),traditionally derived at a monthly scale,are widely used drought indices.To overcome temporalresolution limitations,we have previously developed and published a well-validated daily SPI/SPEI in situ dataset.Although having a high temporal resolution,this in situ dataset presents low spatial resolution due to the scarcity of stations.Therefore,based on the China Meteorological Forcing Dataset,which is composed of data from more than 1,000 ground-based observation sites and multiple remote sensing grid meteorological dataset,we present the first high spatiotemporal-resolution daily SPI/SPEI raster datasets over China.It spans from 1979 to 2018,with a spatial resolution of 0.1°×0.1°,a temporal resolution of 1-day,and the timescales of 30-,90-,and 360-days.Results show that the spatial distributions of drought event characteristics detected by the daily SPI/SPEI are consistent with the monthly SPI/SPEI.The correlation between the daily value of the 12-month scale and the monthly value of SPI/SPEI is the strongest,with linear correlation,Nash-Sutcliffe coefficient,and normalized root mean square error of 0.98,0.97,and 0.04,respectively.The daily SPI/SPEI is shown to be more sensitive to flash drought than the monthly SPI/SPEI.Our improved SPI/SPEI shows high accuracy and credibility,presenting enhanced results when compared to the monthly SPI/SPEI.The total data volume is up to 150 GB,compressed to 91 GB in Network Common Data Form(NetCDF).It can be available from Figshare(https://doi.org/10.6084/m9.figshare.c.5823533)and ScienceDB(https://doi.org/10.57760/sciencedb.j00076.00103).

Mapping and ranking global mortality,affected population and GDP loss risks for multiple climatic hazards

Coping with extreme climate events and its related climatic disasters caused by climate change has become a global issue and drew wide attention from scientists, policy-makers and public. This paper calculated the expected annual multiple climatic hazards intensity index based on the results of nine climatic hazards including tropical cyclone, flood, landslide, storm surge, sand-dust storm, drought, heat wave, cold wave and wildfire. Then a vulnerability model involving the coping capacity indicator with mortality rate, affected population rate and GDP loss rate, was developed to estimate the expected annual affected population, mortality and GDP loss risks. The results showed that： countries with the highest risks are also the countries with large population or GDP. To substantially reduce the global total climatic hazards risks, these countries should reduce the exposure and improving the governance of integrated climatic risk; Without considering the total exposure, countries with the high mortality rate, affected population rate or GDP loss rate, which also have higher or lower coping capacity, such as the Philippines, Bangladesh and Vietnam, are the hotspots of the planning and strategy making for the climatic disaster risk reduction and should focus on promoting the coping capacity.