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1.
为有效开展高温中暑气象预报,对河北省中暑病例资料与气象条件进行了分析,确定了河北省可能发生中暑的日最高气温临界最低指标,建立了基于温湿度组合的暑热指数计算公式,依据日最高气温、暑热指数及其持续时间将中暑气象等级划分为四级,并依据不同等级对人体的影响,确定了不同等级的防范提示建议用语。从多地气象条件、中暑病例、分级指标应用三个方面对指标划分的合理性进行检验。结果表明:等级预报指标划分与河北省夏季气候分布特征相一致;中暑病例97 %以上发生在极易中暑和易发生中暑级别;分级指标应用试报检验预报准确率达到81.2 %。该指标对河北省中暑气象等级预报服务业务开展及公众有效防范中暑具有较好的指导性。  相似文献   

2.
4种城市下垫面地表温度年变化特征及其模拟分析   总被引:2,自引:0,他引:2  
利用对沥青、水泥、裸地和草地等4种城市下垫面地表温度的2年观测资料,系统分析了4种城市下垫面地表温度年变化特征及其影响因素,建立了地表温度模拟模型.主要结果:(1)4种城市下垫面日平均温度、日最高温度、日最低温度的年变化特征总体与气温一致,不同下垫面间温度差异在夏半年均大于冬半年.(2)沥青、水泥、裸地和草地的日平均温...  相似文献   

3.
利用1980—2014年宁波市气象观测资料和2011—2014年6—8月宁波市中暑病例资料,基于现有中暑气象等级,通过对气象因素和中暑事件进行相关分析,采用分位数法建立了新的中暑气象等级。结果表明:本文采用第45、第70和第85分位数对宁波市日最高气温和炎热指数进行了新的等级划分,并结合中暑事件与高温持续时间对高温中暑气象等级划分进行了改进,将宁波地区中暑气象等级分为可能发生中暑、易发生中暑、较易发生中暑和极易发生中暑4个等级。对改进的高温中暑气象等级验证和对比分析表明,改进后的高温中暑气象等级划分标准更适合宁波地区,由气象条件和中暑实况确定的高温中暑等级基本可反映人体中暑的风险,对实际中暑气象等级预报更具指导作用。  相似文献   

4.
高温中暑气象等级评定方法   总被引:3,自引:0,他引:3       下载免费PDF全文
陈辉  黄卓  田华  吴昊 《应用气象学报》2009,20(4):451-457
在全球气候变化的大背景下, 高温热浪天气频繁出现, 由其引发的群发性中暑事件不断发生。为了有效预防极端高温天气对人体健康的影响, 利用全国358个重点城市1996-2005年逐日地面气象观测资料, 通过对气象要素与中暑的相关分析, 选择炎热指数为气象指标对引发中暑的气象条件进行了等级划分, 同时考虑不同程度高温天气的持续时间确定了高温中暑气象等级, 分别为可能发生中暑、较易发生中暑、易发生中暑和极易发生中暑4个等级。利用武汉市1994年和1995年7 -8月中暑人数与高温中暑气象等级进行对比分析, 结果表明:两者具有较好的对应关系。  相似文献   

5.
南宁市夏季不同下垫面温度特征分析与预报研究   总被引:4,自引:4,他引:4       下载免费PDF全文
对2000年至2002年4~9月南宁市下垫面表面温度观测资料的分析表明,下垫面温度明显高于百叶箱气温,尤其是日最高温度差异更大。而不同下垫面之间的温度变化,也有较大不同。下垫面温度的变化与其它气象因子密切相关。在上述分析的基础上,应用统计学方法建立了几种下垫面表面温度的预报方程。  相似文献   

6.
本文回顾了中国夏季高温研究的近期进展,重点关注极端高温和"热带夜"(即夜间高温)的变化规律及其影响因子。文中讨论了最近几十年中国高温频率的长期趋势和年代际变化,指出高温频率的变化规律存在时间和空间差异。文中重点论述了环流、海温、下垫面等因子对高温天气的影响,并将极端高温与热带夜进行比较,指出两种高温的发生机制明显不同。此外,文中还对未来的可能研究方向做了探讨。  相似文献   

7.
4种典型城市下垫面日平均温度、日最高温度、日最低温度的逐月变化特征总体与气温变化相似,不同下垫面问温度差异夏半年均大于冬半年。沥青、水泥、砂石和草地日平均温度、日最高温度全年均高于气温,日最低温度与气温差异不大,表明典型城市下垫面对大气具有一定的加热作用。气温、日照时数、总云量、日平均相对湿度等气象因子与4种下垫面的地表温度相关性显著。建立了4种下垫面各温度参数依赖于日平均、日最高、日最低气温、日照时数、日平均相对湿度和总云量等影响因子的回归模拟方程,因此利用精细化数值预报资料代入方程就可以得出城市沥青、水泥、砂石和草地4种下垫面地表温度,提高城市气象服务效率。  相似文献   

8.
以合肥市气象站为中心,利用1990~2006年的Landsat TM影像,获取不同半径圆形缓冲区范围内下垫面土地分类信息以及对应年份的气温年均值、极值、日定时数据资料,分析了下垫面各土地类型及其变化和站点周边热岛效应的关系.分析得出:城市热岛与建设用地有着最强正相关,与林草地和耕地有着显著负相关,与夜晚水体有着较强正相关.下垫面类型对城市热岛的影响随着每天的不同时刻而变化.4种下垫面类型对城市热岛的影响范围上,建设用地一般在6km以内、林草地4km以内、耕地在4km时最显著,水体则随着距离的增加,其影响范围缓慢上升到8 km.同时,通过分析土地利用年变化和城市热岛效应变化的关系,进一步验证了城市发展对城市热岛效应起着至关重要的作用.最高温和14时(北京时间)热岛强度年变化与土地利用年变化有着较强的相关性.另外,迁站后热岛效应明显减弱.最后,重点探讨了下垫面类型和热岛效应关系的可能原因.  相似文献   

9.
武汉中暑人数与体感温度、CDH的关系以及中暑发病的预报   总被引:6,自引:0,他引:6  
建国以来,武汉市仅在1971年和1988年发生过两次中暑人数超过千人的纪录.本文研究了这两年7月中暑人数与体感温度、制冷度时(CDH)的关系,发现两者之间是高度显著的正相关关系,信度达到0.001水平.当体感温度和CDH值达到一定标准、并持续5天~7天,中暑病人就会急剧增多.体感温度和CDH与中暑的这种关系,不仅可以从病理学得到解释,而且还具有中期趋势预报的意义.  相似文献   

10.
简单介绍了城市空气污染指数预报系统(CAPPS)的功能和特点;给出了空气污染预报条件分级的评价标准及其内容描述,根据污染指数将污染等级划分为5个级别,并指出了不同程度的空气污染可能对人体造成的不利影响以及相应的预防措施;最后,对武汉市近年来空气质量状况与预报结果进行了讨论。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration.  相似文献   

16.
The atmospheric and oceanic conditions before the onset of EP El Ni?o and CP El Ni?o in nearly 30 years are compared and analyzed by using 850 hPa wind, 20℃ isotherm depth, sea surface temperature and the Wheeler and Hendon index. The results are as follows: In the western equatorial Pacific, the occurrence of the anomalously strong westerly winds of the EP El Ni?o is earlier than that of the CP El Ni?o. Its intensity is far stronger than that of the CP El Ni?o. Two months before the El Ni?o, the anomaly westerly winds of the EP El Ni?o have extended to the eastern Pacific region, while the westerly wind anomaly of the CP El Ni?o can only extend to the west of the dateline three months before the El Ni?o and later stay there. Unlike the EP El Ni?o, the CP El Ni?o is always associated with easterly wind anomaly in the eastern equatorial Pacific before its onset. The thermocline depth anomaly of the EP El Ni?o can significantly move eastward and deepen. In addition, we also find that the evolution of thermocline is ahead of the development of the sea surface temperature for the EP El Ni?o. The strong MJO activity of the EP El Ni?o in the western and central Pacific is earlier than that of the CP El Ni?o. Measured by the standard deviation of the zonal wind square, the intensity of MJO activity of the EP El Ni?o is significantly greater than that of the CP El Ni?o before the onset of El Ni?o.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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  相似文献   

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