山东省人工增雨效果检验软件的设计与实现

采用区域对比和区域分层历史回归方法,基于GIS平台和逐时雨量资料建立了山东省人工增雨效果检验系统。该系统由逐时雨量资料处理程序、雨量下载网站、人工增雨效果检验程序三部分组成,可完成地面和飞机人工增雨效果检验工作,为开展地面、飞机人工增雨效果检验业务提供了系统支持。     

人工增雨效果检验统计方案设计

选取陕西关中地区历史上未进行人工增雨作业的 1 0次层状云降水过程的小时雨量 ,针对陕西省人工增雨作业现状 ,把关中地区划分成 8个区域 ,采用区域回归评估方法 ,设计出一种适用于关中地区实际作业效果检验的新统计方案 ,结果得出了相关较好的区域间的回归方程 ,根据实际作业情况和高空风确定目标区或对比区 ,即可得出整个区域内作业后雨量的增加值。     

一次春季人工增雨作业条件分析

利用常规气象观测资料和雷达卫星等资料对2016年春季承德市一次火箭人工增雨的物理量、云系演变、探空资料、雷达参数等作业条件进行分析,结论如下:(1)缓慢移动的西风槽天气系统、充沛的水汽辐合条件有利于较强降水的产生。(2)人工增雨的最佳作业时机应选在处于发展阶段的云系且降水回波强度普遍25dBz,回波顶高度在5km左右,增雨效果比较明显。(3)数值预报产品能够比较准确地预测云系的发展演变趋势以及垂直结构,对确定作业潜力区及作业时间起到积极作用。(4)选择两个自然降水相近的区域,建立统计关系,可由对比区降水量推算出目标区降水期望值,将推算值与目标区实测降水相比,即可得到目标区人工增雨净增加降水量和相对增雨率。     

2004年春夏季海南火箭人工增雨效果检验

运用双比分析和降水量区域历史回归两种分析方法,对2004年春夏季海南省的火箭人工增雨作业进行了效果的统计检验,选用1962~2001年的资料建立了对比区—人工增雨作业目标区回归方程。初步计算表明,2004年春夏季人工增雨作业141 d约增加降水199.6 mm,降水总量约24.6×108m3,投入与产出比为1:37。     

2006年北京市人工增雨作业效果统计分析

利用区域历史回归方案对北京市2006年人工增雨作业效果进行统计评估,选择区域平均日雨量作为统计变量,北京市2006年共有43个催化作业日,其中41个为增雨作业日,作业区域位于北京市北部,面积大约为100 km×50 km.评估结果表明,北京市2006年人工作业相对增雨13%,绝对增雨39 mm,但增雨效果不显著.本文根据催化技术状况对作业日进行分类统计分析,得到21个地面催化充分作业日相对增雨34%,显著度较高,u检验达0.019;29个地面和飞机催化充分作业日相对增雨37%,u检验显著度为0.022;8个飞机作业日相对增雨48%,增雨显著度较低;12个催化不充分作业日相对减雨49%;2个过量播撒消雨作业日相对减雨12%,结果也不显著.分类统计分析表明,对目标区进行充分催化是获得好的催化效果的前提.     

两次飞机增雨作业效果的非参数检验

本文针对我省飞机增雨作业区域的不确定性，采用移动的“影响区”和一个与之相对应的“对比区”的划分方法，对１９８９年９月２５日和９月２６日两次飞机增雨作业，用Ｗ－Ｍ－Ｗ法的ｕ检验、符号检验和Ｗｉｌｃｏｘｏｎ带符号的秩和检验三种方法［１］对作业的增雨效果进行了非参数检验。结果表明：作业开始后３小时“影响区”与“对比区”雨量有显著性差异，人工催化使影响区雨量较对比区明显增大；而作业开始后３小时影响区雨量与同区域作业前３小时雨量无显著差异或比作业前减小，这可能是由于作业时段处于系统后部，降水系统和云层已开始减弱，人工增雨率被自然降水的时间变率覆盖所致。     

飞机人工增雨的农业效益评估

利用催化剂线源扩散模式确定人工增雨作业后的目标区,并采用非随机活动对比区和目标区分层历史回归的方法估算作业效果。这评估增雨对农业的影响,利用自然降水对农作物产量贡献的积分回归,获得降水对农作物贡献系数。建立了每次人工增雨对主要农作物的经济效益模型。从而可根据增雨量对农作物产生的直接经济效益进行实时、动态、定量评估。     

江西省人工增雨统计检验系统设计与实现

介绍了基于VB6．0数据库编程技术的江西省人工增雨统计检验系统的设计思路、实现方法及具备的功能,阐述了区域历史回归和双比分析两种统计分析方法在人工增雨效果检验中的应用。选取2008年贵溪市开展的2次人工增雨作业进行效果检验及系统应用检验,利用系统提供的区域历史回归分析方法,计算得到人工增雨作业相对增雨率约31．9％,增雨效果显著。     

山东济宁地区人工增雨效果检验

利用国内外普遍应用的区域雨量对比和历史区域回归试验2种增雨效果统计检验方法,分析适用于山东济宁地区人工增雨效果检验的评估方法。运用区域雨量对比试验计算出2次稳定性降水过程增加的降水量,运用历史区域回归试验法计算了2006~2009年济宁地区人工增雨作业的平均增雨量,对2月和4月的增雨效果进行了对比分析。结果表明:效果检验方法的不同导致人工增雨的降水量增加效果差别较大,利用区域雨量对比方法对济宁地区人工增雨效果评估非常实用。     

陕西飞机人工增雨效果统计检验方法研究

应用针对陕西省飞机人工增雨作业特点设计的区域回归统计方案,对2002、2003、2006年春、秋季飞机增雨分别进行效果分析,结果表明:春季11架次08?20时平均增雨量1.6 mm,作业后3 h平均增雨量0.3 mm;秋季13架次08?20时平均增雨量3.6 mm,作业后3 h平均增雨量1.3 mm;通过成对试验符号秩和检验,显著性水平均优于5%,表明作业效果显著;分析结果说明了统计方案的可行性。基于该区域回归统计方案开发的飞机增雨效果评估系统,实现对增雨效果的及时、客观、定量评估。     

CHARACTERISTICS AND TRENDS OF CLIMATIC EXTREMES IN CHINA DURING 1959–2014

The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics.     

Could the Recent Taal Volcano Eruption Trigger an El Ni?o and Lead to Eurasian Warming?

正The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth's climate and environment.     

VARIABILITY OF INTER-ANNUAL RELATIONSHIP BETWEEN INDIAN OCEAN DIPOLE AND HUAXI REGION’S AUTUMN PRECIPITATION

The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region.     

ANALYSIS OF “BIMODAL PATTERN” STORM ACTIVITY CHARACTERISTICS OF THE BAY OF BENGAL

Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.     

LOW-FREQUENCY CIRCULATION AND EXTENDED-RANGE FORECAST IN CONNECTION WITH AUTUMN EXTREME HEAVY RAINFALL PROCESS IN HAINAN

Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d.     

AN ATTRIBUTION ANALYSIS OF CHANGES IN POTENTIAL EVAPOTRANSPIRATION IN THE BEIJING–TIANJIN–HEBEI REGION UNDER CLIMATE CHANGE

Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region.     

Revisiting the Concentration Observations and Source Apportionment of Atmospheric Ammonia

正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on     

全球贸易隐含碳变化及其影响分析

基于最新的GTAP8 (Global Trade Analysis Project）数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。     

COMPARATIVE ANALYSIS OF VARIOUS DATA OF AIR–SEA TEMPERATURE DIFFERENCE AND ITS VARIATION ACROSS SOUTH CHINA SEA IN THE PAST 35 YEARS

Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter.     

Retrieval of outgoing longwave radiation from COMS narrowband infrared imagery

Hourly outgoing longwave radiation(OLR) from the geostationary satellite Communication Oceanography Meteorological Satellite(COMS) has been retrieved since June 2010. The COMS OLR retrieval algorithms are based on regression analyses of radiative transfer simulations for spectral functions of COMS infrared channels. This study documents the accuracies of OLRs for future climate applications by making an intercomparison of four OLRs from one single-channel algorithm(OLR12.0using the 12.0 μm channel) and three multiple-channel algorithms(OLR10.8+12.0using the 10.8 and 12.0 μm channels; OLR6.7+10.8using the 6.7 and 10.8 μm channels; and OLR All using the 6.7, 10.8, and 12.0 μm channels). The COMS OLRs from these algorithms were validated with direct measurements of OLR from a broadband radiometer of the Clouds and Earth's Radiant Energy System(CERES) over the full COMS field of view [roughly(50°S–50°N, 70°–170°E)] during April 2011.Validation results show that the root-mean-square errors of COMS OLRs are 5–7 W m-2, which indicates good agreement with CERES OLR over the vast domain. OLR6.7+10.8and OLR All have much smaller errors(～ 6 W m-2) than OLR12.0and OLR10.8+12.0(～ 8 W m-2). Moreover, the small errors of OLR6.7+10.8and OLR All are systematic and can be readily reduced through additional mean bias correction and/or radiance calibration. These results indicate a noteworthy role of the6.7 μm water vapor absorption channel in improving the accuracy of the OLRs. The dependence of the accuracy of COMS OLRs on various surface, atmospheric, and observational conditions is also discussed.