Discussing the flux characteristics of wheat field under disastrous weather background has important scientific significance to understand the occurrence regularity of hazards deeply and to tackle the disasters. Based on observational data of eddy covariance system at Zhengzhou agro-meteorological experimental station, the flux characteristics of wheat field under dry-hot wind weather condition in 2013 and 2017 were analyzed comparatively. The results show that the dry-hot wind weakened photosynthesis capacity of wheat canopy, and the influence of dry-hot wind on flux was obvious in the daytime.  During the day, the CO2 flux of wheat field under different grades of dry-hot wind weather decreased obviously than that in normal weather, it decreased by 33.0% to 59.7% averagely, and the peak value reduced 25.0% to 38.2%. Meanwhile, the peak value appeared ahead of time with various degrees. The effect of dry-hot wind on flux was different in different stages of grouting, and the average CO2 flux decreased most when the hazard occurred in middle stage of grain filling. The net radiation enhanced under dry-hot wind weather condition, the exchange of soil heat flux, latent heat flux and sensible heat flux increased in varying degree, and the peak value of energy flux decreased under severe dry-hot wind weather, light dry-hot wind weather and normal weather condition in turn. The allocation of available energy varied obviously under dry-hot wind weather condition, the value of evaporation ratio was biggest under severe dry-hot wind weather, followed by light dry-hot wind weather and normal weather, meanwhile, the peak value under light dry-hot wind weather occurred backward obviously.

In September 2015, four dual-polarized weather radars of X-band were set up and conducted the observation test in Beijing area by Beijing Meteorological Bureau. Based on the observation data of the three radars on 30 June 2016, the observation parameters of radars have been conducted initial quality assessment by using the statistical method of standard deviation distribution. The results are as follows: (1) The 73.5%-77.9% of the total observation data of the reflectivity from the three radars conformed to the theoretical standard deviation distribution. It suggested that the fluctuation of the reflectivity data basically conformed to the theoretical distribution. (2) The 68.4%-81.4% of the total observation data of the differential reflectivity conformed to the theoretical standard deviation distribution. The fluctuation of data from Fangshan radar was the largest among the three radars. (3) For the cross correlation coefficient among the three radars, 45.7%-63.5% of the standard deviations conformed to the theory value. The data from Fangshan radar fluctuated most while data from the rest two radars showed the same scale of fluctuation. (4) For the standard deviations of differential-phase, 73.5%-83.9% of the data showed consistency with theoretical data. The fluctuation of data from Fangshan radar was relatively large. Compared with the other three observation parameters of radars, the variation of differential-phase was relatively small. 

Based on the daily mumps cases，meteorological data from 2005 to 2011 in Yinchuan，the epidemic characteristics of the mumps cases and relations with the meteorological factors were analyzed by using the methods of climatic inclination rate and the correlation analysis． The results show that the number of mumps cases presented increasing trend，the crowd from the age of 1 to 20 with mumps cases accounted for 93． 7% of the total mumps cases in Yinchuan，and they were the main easy infected crowd，while the crowd from the age of 6 to 7 was the key crowd of prevention and control． The monthly variation of mumps cases presented increase trend from February to May and September to December，while decline trend in summer and winter．The number of mumps cases accounted for 44． 4% and 5． 0% of the total number in Xingqing and Lingwu，respectively． The correlations were significant between the number of mumps cases and the weekly mean pressure，weekly mean temperature，weekly maxium temperature difference，mean relative humidity，weekly minimum relative humidity and weekly sunshine hours． The number of mumps cases was obviously affected by the meteorological factors of the first one to fourth weeks，so mumps cases could be forecasted by using the preceding meteorological factors．

 

TheWorldMeteorologicalOrganization (WMO) considers thirty years long enough to eliminate year-to-year variations,and recommends that countries prepare climate normals for the official and researchers 30-year normals periods. In addition, many WMO members, including the China, update their normals at the completion of each decade. The last updating of climate normals is for 1971 to2000, and the new 30-yearnormals for1981-2010 willbe time forpreparing. So, it is necessary to introduce the climate normalsmethods and elements ofU. S. and Canada for1971 to 2000, in order to provide a comparison for our new climate normals.
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By using a total of 49 years（1955~2003）duststorm data from 13 representative sites in Ningxia，We established a intensity standard of regional dust storm in Ningxia，divided extremely strong，strong，andordinary dust storm after 1955，and studied the time and intensity evolving features of Ningxia dust storm.By the analyse of temporal-spatial distribution features of sand stormsc ontrast to Gansu province，Some scientific basis of sand storm monitoring，warning，forecasting and preventing were provided for the east of Northwest China.