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1.
Studied are the effects that variations of meteorological parameters at different time scales in Naberezhnye Chelny city produce on people suffering from ischemic heart disease. The number of ambulance calls from 2010 to 2012, meteorological parameters, and some biometeorological indices are compared by the cross-correlation analysis. Demonstrated is the absence of statistically significant correlation between the daily series of ambulance calls due to ischemic heart disease during the period under study, on the one hand, and average daily series of major meteorological parameters and the most frequently used biometeorological indices, on the other hand. Revealed is the correlation between the number of ambulance calls and the intradaily variations of air pressure and air temperature at the time scale of 3 hours. Proposed is a parameter (biometeorological index of weather effects, IWE) taking into account the total effects of intradaily variations of air pressure and air temperature and characterized by statistically significant correlation with the number of ambulance calls made by people suffering from ischemic heart disease.  相似文献   

2.
利用2002-2006年沈阳市逐日急性心肌梗塞死亡病例和同期逐日地面气象资料,分析气象条件对沈阳市急性心肌梗塞死亡的影响。结果表明:不同季节急性心肌梗塞患者死亡数与气象因子的相关性存在着明显的差异,在各个季节中最主要的影响因子是气压和气温,而春季相对湿度,夏季降水与死亡数之间也存在着一定的相关关系;为评价气象要素的综合作用,应用逐步聚类法,定性地给出了各个季节高发的天气类型,在同一季节内,不同性别高发的天气类型既存在一致性,也存在着明显的差异,这种差异可能与男性和女性的生理条件和生活习惯有关。研究结果可为疾病的气象预报预警提供参考。  相似文献   

3.
On the basis of reanalysis data and hydrodynamic modeling the spatial-temporal features of Wallace-Gutzler circulation indices, calculated at daily intervals, are studied. The circulation index extremes are interpreted as “weather regimes” with the alteration closely related to the low frequency variability of the atmospere. The outliers and extreme values are studied using nonparametric statistics and exploratory techniques. On the basis of the experiments performed assessments of the potential predictability of the outlier and extreme value characteristics for the summer and winter seasons are given.  相似文献   

4.
The interpretation and communication of fire danger warning levels based on fire weather index values are critical for fire management activities. A number of different indices have been developed for various environmental conditions, and many of them are currently applied in operational warning systems. To select an appropriate combination of such indices to work in different ecoregions in mountainous, hilly and flat terrain is challenging. This study analyses the performance of a total of 22 fire weather indices and two raw meteorological variables to predict wildfire occurrence for different ecological regions of Austria with respect to the different characteristics in climate and fire regimes. A median-based linear model was built based on percentile results on fire days and non-fire days to get quantifiable measures of index performance using slope and intercept of an index on fire days. We highlight the finding that one single index is not optimal for all Austrian regions in both summer and winter fire seasons. The summer season (May–November) shows that the Canadian build-up index, the Keetch Byram Drought Index and the mean daily temperature have the best performance; in the winter season (December–April), the M68dwd is the best performing index. It is shown that the index performance on fire days where larger fires appeared is better and that the uncertainties related to the location of the meteorological station can influence the overall results. A proposal for the selection of the best performing fire weather indices for each Austrian ecoregion is made.  相似文献   

5.
对2005-2007年4-9月安徽省冰雹、雷雨大风等强对流天气日数进行统计,分析了基于探空资料计算的不稳定指标与强对流天气发生的关系。结果表明:K指数、A指数、沙氏指数和对流有效位能、归一化对流有效位能和对流抑制能量这几个指标对于强对流天气指示意义较好。基于此结果,挑选K指数、沙氏指数和对流有效位能针对不同季节划分阈值,建立强对流天气潜势预警指标,并利用中尺度模式MM5的数值预报产品计算该指标,对2005-2010年13个强对流天气过程预报结果进行对比检验表明,MM5模式给出的强对流天气潜势预警产品对大多数过程均能起到预警作用。对其中两次强对流天气过程的进一步分析表明,模式具备预报强对流发生潜势的能力,预报结果对强对流天气发生的时间、落区有预警意义。  相似文献   

6.
利用新疆昌吉佃坝绿洲区陆气相互作用观测站2020年3—11月的地表辐射观测数据和同期的天气现象观测记录数据,定量分析昌吉绿洲区不同时间尺度和不同天气条件下的地表辐射变化特征。结果表明:(1)辐射分量日均值和日峰值时间有季节性差异,特殊天气现象对辐射通量有影响。(2) 地表辐射月曝辐量随季节变化显著。(3) 地表反照率月平均日变化季节性明显,晴天时地表反照率呈平滑的“U形”曲线,非晴天时曲线变化皆不规则、不平滑。(4)不同天气下辐射分量有独特日变化特征,轻雾、雨天、大风、扬沙、多云天等典型天气会给辐射分量带来不同程度的衰减,雨天、大风和多云天气衰减最为明显。  相似文献   

7.
In this study, satellite-based daily precipitation estimation data from precipitation estimation from remotely sensed information using artificial neural networks (PERSIANN)-climate data record (CDR) are being evaluated in Iran. This dataset (0.25°, daily), which covers over three decades of continuous observation beginning in 1983, is evaluated using rain-gauge data for the period of 1998–2007. In addition to categorical statistics and mean annual amount and number of rainy days, ten standard extreme indices were calculated to observe the behavior of daily extremes. The results show that PERSIANN-CDR exhibits reasonable performance associated with the probability of detection and false-alarm ratio, but it overestimates precipitation in the area. Although PERSIANN-CDR mostly underestimates extreme indices, it shows relatively high correlations (between 0.6316–0.7797) for intensity indices. PERSIANN-CDR data are also used to calculate the trend in annual amounts of precipitation, the number of rainy days, and precipitation extremes over Iran covering the period of 1983–2012. Our analysis shows that, although annual precipitation decreased in the western and eastern regions of Iran, the annual number of rainy days increased in the northern and northwestern areas. Statistically significant negative trends are identified in the 90th percentile daily precipitation, as well as the mean daily precipitation from wet days in the northern part of the study area. The positive trends of the maximum annual number of consecutive dry days in the eastern regions indicate that the dry periods became longer in these arid areas.  相似文献   

8.
Forecasting future fire activity as a function of climate change is a step towards understanding the future state of the western mixedwood boreal ecosystem. We developed five annual weather indices based on the Daily Severity Rating (DSR) of the Canadian Forest Fire Weather Index System and estimated their relationship with annual, empirical counts of lightning fire initiation for 588 landscapes in the mixedwood boreal forest in central-eastern Alberta, Canada from data collected between 1983 and 2001 using zero-inflated negative binomial regression models. Two indices contributed to a parsimonious model of initiation; these were Seasonal Severity Rating (SSR), and DSR-sequence count. We used parameter estimates from this model to predict lightning fire initiation under weather conditions predicted in 1 × CO2 (1975–1985), 2 × CO2 (2040–2049) and 3 × CO2 (2080–2089) conditions simulated by the Canadian Regional Climate Model (CRCM). We combined predicted initiation rates for these conditions with existing empirical estimates of the number of fire initiations that grow to be large fires (fire escapes) and the fire size distribution for the region, to predict the annual area burned by lightning-caused fires in each of the three climate conditions. We illustrated a 1.5-fold and 1.8-fold increase of lightning fire initiation by 2040–2049 and 2080–2089 relative to 1975–1985 conditions due to changes in fire weather predicted by the CRCM; these increases were calculated independent of changes in lightning activity. Our simulations suggested that weather-mediated increases in initiation frequency could correspond to a substantial increase in future area burned with 1.9-fold and 2.6-fold increases in area burned in 2040–2049 and 2080–2089 relative to 1975–1985 conditions, respectively. We did not include any biotic effects in these estimates, though future patterns of initiation and fire growth will be regulated not only by weather, but also by vegetation and fire management.  相似文献   

9.
珠三角地区前汛期强对流潜势预报方法研究   总被引:3,自引:0,他引:3  
利用2004—2006年前汛期探空资料计算的物理量,选取与强对流天气相关性好的大气温湿类(整层比湿积分IntegralQ)、层结稳定度类(K指数)、动力类(潜在下冲气流指数MDPI)、热力动力综合类(瑞士第一雷暴指数SWISS00)作为预报因子,通过对各指数的空间分布特征和数值进行二值Logistic回归分析,得到各指数的参数估算值,建立强对流诊断预报方程,得到前汛期强对流潜势预报因子P,从而制作珠江三角洲(以下简称珠三角)地区未来12小时出现强对流天气的潜势预报。并用此法回报2003—2006年3—6月前汛期的强对流天气。结果表明,P值大于0.9的准确率可达77.5%,P值小于0.5出现强天气的概率仅为3.8%。由于资料有限,对2007年3—4月发生的7次强对流的经验检验效果不明显,但P值小于0.5时不发生强对流的经验检验效果明显。此法对珠三角地区的短时强降水和雷雨大风等强对流天气的临近监测预警有较好的指示意义。  相似文献   

10.
In this study, the influence of the East Atlantic Oscillation (EAO) on the climate indices based on the daily minimum temperature at eight stations in Serbia was examined. The following climate indices were analyzed: frost days (FD), cold nights (TN10p), warm nights (TN90p), minimum value of daily minimum temperature (TNn), tropical nights (TR), and cold spell duration indice (CSDI). Analysis of correlation between the East Atlantic Index (EAI) and the geopotential at 500 hPa, as well as between the EAI and climate indices was realized for all seasons and months during the period 1950–2009. Two characteristic situations for the extreme positive and negative values of the EAI were analyzed. Seasonal and monthly trend analyses of climate indices were performed. Decreases of FD and TN10p and increases of TN90p and TR were observed. It was found that the negative correlation prevailed between the EAI and TN10p/FD, and positive one between the EAI and TN90p/TR for all seasons and months. The highest correlation was observed between the EAI and TN90p in February.  相似文献   

11.
沪宁高速公路路面温度变化特征及统计模型   总被引:5,自引:0,他引:5       下载免费PDF全文
使用2006年7月-2007年6月沪宁高速公路沿线梅村和仙人山站附近的逐分钟路面温度、气温、湿度、风向、风速、降水气象资料, 分析了梅村和仙人山不同季节和不同天气状况下路面温度的日变化特征。结果表明:不同季节路面温度和气温具有明显的日变化;日出至日落时段,路面温度与气温有较大差异。在此基础上,应用逐步回归方法建立了梅村和仙人山最高和最低路面温度统计模型, 得出最低路面温度模型模拟结果与实况的变化趋势接近,误差绝对值不超过2℃, 具有很好的实际应用价值; 而最高路面温度模型在一定程度上模拟结果偏差较大,实际应用中需进行适当修订。  相似文献   

12.
The article in hand presents a comparative analysis of unweighted thermic and hygric index series of different European regions (northern Switzerland, Germany, the Czech Republic, northern Italy, ancient Hungary, Poland and Spain). Besides methodological aspects about the formation of indices, especially the progress as well as the question of similarity development of these series in the 16th century are discussed and shown on the balance sheet. It becomes evident that with respect to the temperature on the level of unweighted indices the European regions of Germany, the Czech Republic and Switzerland are very similar during all seasons. In winter and summer these correlations are especially evident, during the transitional seasons they are smaller. Larger differences exist between the central European core region and the adjacent areas of research. In principle, the hygric differences are larger than the thermic ones.In the course of the sixteenth century marked cooling phases occurred during all seasons with increasing accentuation. These phases were typical for the climate of the Little Ice Age. In addition to this long-term analysis, some outstanding years of extreme weather like those of 1540, 1573 and 1587 are presented, in the course of which questions of climatic impact are included. Finally, recent instrumental data was used to conduct an analysis that compared the similarities between the respective regions and the similarities between the empirical data and indices. On the one hand, this confirmed the spatial pattern, on the other hand the usability of the indices.  相似文献   

13.
This study extends a stochastic downscaling methodology to generation of an ensemble of hourly time series of meteorological variables that express possible future climate conditions at a point-scale. The stochastic downscaling uses general circulation model (GCM) realizations and an hourly weather generator, the Advanced WEather GENerator (AWE-GEN). Marginal distributions of factors of change are computed for several climate statistics using a Bayesian methodology that can weight GCM realizations based on the model relative performance with respect to a historical climate and a degree of disagreement in projecting future conditions. A Monte Carlo technique is used to sample the factors of change from their respective marginal distributions. As a comparison with traditional approaches, factors of change are also estimated by averaging GCM realizations. With either approach, the derived factors of change are applied to the climate statistics inferred from historical observations to re-evaluate parameters of the weather generator. The re-parameterized generator yields hourly time series of meteorological variables that can be considered to be representative of future climate conditions. In this study, the time series are generated in an ensemble mode to fully reflect the uncertainty of GCM projections, climate stochasticity, as well as uncertainties of the downscaling procedure. Applications of the methodology in reproducing future climate conditions for the periods of 2000–2009, 2046–2065 and 2081–2100, using the period of 1962–1992 as the historical baseline are discussed for the location of Firenze (Italy). The inferences of the methodology for the period of 2000–2009 are tested against observations to assess reliability of the stochastic downscaling procedure in reproducing statistics of meteorological variables at different time scales.  相似文献   

14.
短中期降水温度天气过程区域分布的研究   总被引:2,自引:0,他引:2  
运用旋转主分量方法对分布于全国621个站点的候降水量和2214个站的逐日最高最低气温进行分析。得到4个季节的降水气温主特征模态及其相对应的时间变率。分析结果表明,该方法所分解得到的特征模态较好地反映了全国不同区域降水温度演变的差别,依据各模态的相关系数将全国划分为不同的降水温度天气区。最后。获得表征全国不同天气特点的252个代表站,这些站的资料可作为提高要素客观预报、扩展服务领域的基本资料。  相似文献   

15.
傅新姝  谈建国 《气象科技》2015,43(6):1209-1212
电力负荷与气象条件密切相关,为建立上海市日最大电力负荷的预报模型,利用2010—2013年上海市日最大电力负荷数据及同期气象资料,分析日最大电力负荷的时间变化特征及其与气象因子的相关性,并基于滤波技术将日最大电力负荷分离为时间趋势项和逐日变化项,用逐步回归方法针对冬季和夏季分别建立预测模型。结果表明:①上海日最大电力负荷的各个节假日效应存在差异,春节节假日效应持续时间最长,影响最大,国庆节假期前半段节假日效应明显大于后半段。夏季的周末效应最强。②采用逐步回归方法建立的气象预报模型效果较好,回代年和预测年的平均预测相对误差均小于5%。  相似文献   

16.
对2005-2007年4-9月安徽省冰雹、雷雨大风等强对流天气日数进行统计,分析了基于探空资料计算的不稳定指标与强对流天气发生的关系。结果表明:K指数、A指数、沙氏指数和对流有效位能、归一化对流有效位能和对流抑制能量这几个指标对于强对流天气指示意义较好。基于此结果,挑选K指数、沙氏指数和对流有效位能针对不同季节划分闽值,建立强对流天气潜势预警指标,并利用中尺度模式MM5的数值预报产品计算该指标,对2005—2010年13个强对流天气过程预报结果进行对比检验表明。MM5模式给出的强对流天气潜势预警产品对大多数过程均能起到预警作用。对其中两次强对流天气过程分析表明,模式具备预报强对流发生潜势的能力,预报结果对强对流天气发生的时间、落区有预警意义。  相似文献   

17.
利用气象行业标准《用电需求气象条件等级》中的气象敏感用电量条件指数统计方法,对湖南省97个地面气象观测站1971~2012年逐日气温资料,分析了湖南省各级气象敏感用电量条件日数的时空分布特征,结果表明:洞庭湖区、湘江流域为三级以上高气象敏感用电量日数相对大值区,高气象敏感用电量日数在近年来有上升的趋势,三级气象敏感用电量日数较多的月份集中在7月和8月。  相似文献   

18.
In this study, the applicability of the statistical downscaling model (SDSM) in modeling five extreme precipitation indices including R10 (no. of days with precipitation ≥10?mm?day?1), SDI (simple daily intensity), CDD (maximum number of consecutive dry days), R1d (maximum 1-day precipitation total) and R5d (maximum 5-day precipitation total) in the Yangtze River basin, China was investigated. The investigation mainly includes the calibration and validation of SDSM model on downscaling daily precipitation, the validation of modeling extreme precipitation indices using independent period of the NCEP reanalysis data, and the projection of future regional scenarios of extreme precipitation indices. The results showed that: (1) there existed good relationship between the observed and simulated extreme precipitation indices during validation period of 1991–2000, the amount and the change pattern of extreme precipitation indices could be reasonably simulated by SDSM. (2) Under both scenarios A2 and B2, during the projection period of 2010–2099, the changes of annual mean extreme precipitation indices in the Yangtze River basin would be not obvious in 2020s; while slightly increase in the 2050s; and significant increase in the 2080s as compared to the mean values of the base period. The summer might be the more distinct season with more projected increase of each extreme precipitation indices than in other seasons. And (3) there would be distinctive spatial distribution differences for the change of annual mean extreme precipitation indices in the river basin, but the most of Yangtze River basin would be dominated by the increasing trend.  相似文献   

19.
On the basis of 14-year (1994–2007) series of the semi-annual (January to June) measurements of the atmospheric aerosol microstructure in Dolgoprudny, Moscow region, effects are analyzed of pressure, wind speed, precipitation, and surface temperature inversions on the aerosol particle concentration. It is shown that the weather parameters affect concentration of the particles within a certain range of sizes (0.1 to 1 μm). Concentration of the smaller particles practically does not depend on the weather conditions. The weather effects on large (> 1 μm) particle concentration are not detected due to too high variability of the latter. From three the most available weather parameters (pressure, wind, daily precipitation amount), the observed weather conditions are classified, and for the detected types of weather, typical concentrations are determined of the aerosol particles of different sizes, which allow approximately estimating, from the standard weather data, the aerosol pollution under different meteorological situations.  相似文献   

20.
The results of studying the temporal variability of atmospheric circulation in the Western Arctic (the Norwegian and Barents seas) are presented. The daily dataset of Girs-Vangengeim E, W, and C circulation forms for the period of 1891–2016 is used to describe atmospheric circulation. Special attention is given to the estimation of differences in weather conditions during the modern period of warming (1985–2015) and in the period of the first Arctic warming (1920–1950). For the cold (November-March) and warm (April-October) seasons, the trends in the frequency of occurrence of the circulation forms are determined. The occurrence of the number of consecutive days with the same atmospheric circulation form which can be considered as a characteristic of weather stability during the analyzed period of warming, is computed for both seasons. The prevalence of the E circulation form during the warm season is typical of both periods. The modern period of warming in the study area, as compared to the period of the first warming, is characterized by an increase in the occurrence of the C circulation form with a short duration. It is found that the current climate regime is characterized by an increase in surface air temperature against a background of less stable weather conditions.  相似文献   

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