共查询到20条相似文献，搜索用时 187 毫秒
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基于遥感技术(RS)和地理信息系统(GIS),利用由基于DEM演算的地面最高温度、最小相对湿度和最大风速等格点化气象要素,FY2静止气象卫星逐日降水反演产品和AVHRR积雪监测产品计算网格森林火险天气等级,结合由植被类型、NDVI、地形要素和公路、人口聚居地等要素评估的森林火险风险等级,综合计算得到网格化的西藏森林火险等级。该项业务程序基于MeteoInfo组件建立,能够实现全自动化业务运行。对于森林火灾事件,通过与基于气象站的森林火险天气等级相比,该方法的准确性更高,能为西藏林区森林防火工作提供有效参考。 相似文献
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通过对１９８７年１月￣１９９０年４月期间发生在湖北省的森林火灾过程进行分析，建立了一套较客观的火险天气环流形势预报指标，经过３年多的应用，预报效果良好。另外，还利用地面气象要素分析研究出通过计算燃料中水分的得失，从而得到预报火险等级的方法。经过１９９５年１１月－１９９６年１月的检验，结果表明：这一预报方法具有一定的预报技巧，在林火天气预报中能起很好的参考作用。 相似文献
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采用数理统计的方法,增加了MODIS卫星遥感监测的土壤湿度和热源点预报因子,对河北省气象局原有的森林火险预报模式进行了改进,针对不同区域分别建立了森林火险预报模式,并对2012年河北省森林火灾实际发生情况进行了分析和应用效果检验。结果表明,2012年防火期,实况出现火灾,改进的火险模式预报森林火险气象等级5级为预报完全正确比率达66．3％;预报火险气象等级为4级（高度火险）及以上的正确率达83．1％;预报火险气象等级为3级（中度火险）及以上的正确率达98．8％;在所有的预报样本中,森林火险气象等级预报5级,但实况没有出现火灾的空报率为6．8％。检验结果显示,改进后的森林火险预报模式的应用效果更接近实际情况。 相似文献
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依据云南省迪庆州3站40年的观测资料,利用统计检验结果,同时结合天气预报的时间和空间尺度理论,论证了迪庆州各旅游景点的气象指数预报。用最靠近景区的气象观测站所提供的天气预报资料和逐时观测资料作为预报景区指数的基础,同时根据景区的经纬度、海拔高度、植被状况进行订正,最终获取旅游景区的特种气象预报指数。旅游景区的特种气象预报软件开发应用天气学、数值方法等理论和业务技术方法,用Fortran语言和vB语言编程,研制了迪庆州各景区的紫外线指数、舒适指数、着装指数、火险等级、旅游气象指数系统。该系统软件已投入业务运行。 相似文献
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The most appropriate indices with which to quantify Australian bushfire danger are the McArthur fire danger meters. These meters use meteorological information to produce a fire danger index that is directly related to the chance of a fire starting - and to the severity of a fire once it has started. The Mark 5 forest-fire danger meter uses air temperature, relative humidity and wind speed, plus a drought factor that is calculated using daily rainfall and temperature information.Three years of daily data generated from the CSIRO four-level general circulation model, and thirty years of daily data generated from the CSIRO nine-level model were used to estimate the daily McArthur forest fire danger index for simulations corresponding to present conditions, and to those corresponding to doubled atmospheric CO2. The performance of these models with respect to fire danger was tested by comparing the fire danger index for Sale (in the Eastern part of Victoria, South-eastern Australia) calculated from analysis of daily climatological data with the modelled annual cumulative forest fire danger index for the grid point that was representative of Sale. Data from both models for all Australian grid points were also examined. Both models predict an increase in fire danger over much of Australia for their doubled CO2 scenarios.The results from the models confirm that annually averaged daily relative humidity is the single most important variable in the estimation of forest fire danger on an annual basis, yet the models tend to produce relative humidities that are slightly too low so that the fire danger is overestimated. A simple one-box model of evaporation indicates that the value of relative humidity to be expected under an altered climatic regime depends on the modelled relation between actual and potential evaporation, the present values of relative humidity and evaporation rate, as well as on the expected changes in wind speed. 相似文献
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地市级专业气象预报服务系统 总被引：3，自引：1，他引：2
利用9210传输的气象资料,通过计算预报因子和预报对象间的相关系数,挑选预报因子,建立多因子权重回归方程,用于气象要素、森林火险气象等级、城镇火险气象等级、空气环境质量等级预报。此外,根据调查指标和实践经验,建立了医疗气象、储运气象、商业气象预报判据。 相似文献
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E. I. Ponomarev A. S. Skorobogatova T. V. Ponomareva 《Russian Meteorology and Hydrology》2018,43(7):456-463
Subregional occurrence of fires in Siberian forests and seasonal variations in heat and moisture supply are analyzed. Instrumental data on wildfires registered through satellite monitoring data for the period of 1996–2016 are used. The dynamics of the weather fire danger index (PV-1) and intraseasonal anomalies of the Selyaninov’s hydrothermal coefficient (HTC) defining fire occurrence variation are revealed using meteorological data series for the Siberian subregions. The statistical regularities of the dynamics of the weather fire danger index are summarized for subregions. The separated scenarios are formalized by model functions. The projections of the probability of the scenarios’ implementation, the fire return period, and the respective relative burned area are determined. 相似文献
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A new method of medium-range forecasting of a class of fire hazard is developed based on more precise accounting of accumulated moisture deficiency that is reflected by the Nesterov standard index. A physico-statistical interpretation of hydrodynamic forecasts of fields of meteorological variables is used for finding of prognostic values of the elements of the fire hazard index, using forecasts of maximum air temperature and precipitation in the Novosibirsk region from the earlier developed scheme. The initial set of variables contains data on the isobaric surface geopotential at 500 hPa, surface pressure, temperature at 850 hPa at the regular grid points at 2.5° × 2.5° resolution and their derivatives. For formulation of forecasting equations, the algorithm of model self-organization is used with external criteria. The input of initial information, forecast issuance, displaying results and their delivery to customers based on GIS-technologies are totally automated. 相似文献
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Alexander Arpaci Chris S. Eastaugh Harald Vacik 《Theoretical and Applied Climatology》2013,114(3-4):393-406
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
11.
长期天气预告的物理基础 总被引：1，自引：0，他引：1
“云掩中秋月,雨打上元灯。”“重阳无雨一冬晴。”这两句天气俚谚,很明显的告诉我们,长期天气预告并不是十分时髦的问题。千年前的农民和诗人对於这个问题早就有了深切的注意和相当的认识了。他们凭著经验的提示,诗兴的焕发,作了许多关於这类的俚谚,为的是要诱掖後人们注意天气的前後相互关系。这些天气俚谚是否能够兑现呢?这个问题恐怕是许多人要问的。严格的讲,这类的俚谚大都没有兑现的可能,他们的普遍流行,只不过是表示一个农业国家的 相似文献
12.
Does ??climate change?? seem like a less serious problem than ??global warming?? to Americans and Europeans? Does describing the costs of climate change mitigation in terms of ??higher taxes?? instead of ??higher prices?? reduce public support for such efforts? In an experiment embedded in an American national survey, respondents were randomly assigned to rate the seriousness of ??global warming,?? ??climate change,?? or ??global climate change.?? Contrary to predictions made by a leading political strategist, the full sample and political Independents perceived ??climate change?? and ??global warming?? to be equally serious. Among Republicans, ??climate change?? was perceived to be more serious than ??global warming,?? whereas the reverse was true among Democrats. A similar experiment embedded in a survey of residents of 31 European countries showed that ??global warming?? and ??climate change?? were perceived to be equally serious problems. And an experiment embedded in an American survey showed that describing the increased costs of climate change mitigation legislation via ??higher taxes?? instead of via ??higher prices?? did not reduce popular support for such legislation, also contradicting a political strategy memo. Thus, word choice may sometimes affect public perceptions of the climate change seriousness or support for mitigation policies, but a single choice of terminology may not influence all people the same way, making strategic language choices difficult to implement. 相似文献
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利用全国575个国家级基本气象站1971年1月1日至2005年5月31日的气象观测资料, 选用了5种已得到国际普遍认可或我国国家级预警业务中使用的森林火险气象指数计算方法, 计算了我国长序列的历史逐日森林火险气象指数, 并对这些指数在我国的实际使用效果进行对比分析和应用研究。结果表明: IFFD, INMC, IN, IMN指数可在我国大范围推广使用 (除长江中下游及附近地区), 其中以IFFD指数总体应用效果最好, IMN指数次之。 相似文献
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Daily meteorological data at 263 stations in northern China from 1956 to 2005 were used to calculate various forest fire danger weather (FFDW) indices, such as Nesterov Index (NI), Modified Nesterov Index (MNI), Keetch-Byram Drought Index (KBDI), and Forest Fire Danger Index (FFDI), at different time scales. The relationship between each index and forest fire was analyzed. MNI and FFDI were then selected to study the impact on forest fire danger due to climatic change in northern China in the recent 50?years. Results show that forest fire danger has significantly increased in Northeast China where there is the richest forest resource in China, and also increased in North China. However, it has not changed much in eastern part of Northwest China, and the forest fire danger has even significantly decreased in northern Xinjiang. Significant rise of forest fire danger in Northeast China mainly results from the co-effect of increase of temperature, and decreases of humidity and precipitation. Relative humidity change dominants forest fire danger trends in the four forest regions in northern China. 相似文献
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It is important to perform fire frequency analysis to obtain fire frequency curves (FFC) based on fire intensity at different parts of Victoria. In this paper fire frequency curves (FFCs) were derived based on forest fire danger index (FFDI). FFDI is a measure related to fire initiation, spreading speed and containment difficulty. The mean temperature (T), relative humidity (RH) and areal extent of open water (LC2) during summer months (Dec–Feb) were identified as the most important parameters for assessing the risk of occurrence of bushfire. Based on these parameters, Andrews’ curve equation was applied to 40 selected meteorological stations to identify homogenous stations to form unique clusters. A methodology using peak FFDI from cluster averaged FFDIs was developed by applying Log Pearson Type III (LPIII) distribution to generate FFCs. A total of nine homogeneous clusters across Victoria were identified, and subsequently their FFC’s were developed in order to estimate the regionalised fire occurrence characteristics. 相似文献
17.
High-temporal resolution meteorological output from the Parallel Climate Model (PCM) is used to assess changes in wildland fire danger across the western United States due to climatic changes projected in the 21st century. A business-as-usual scenario incorporating changing greenhouse gas and aerosol concentrations until the year 2089 is compared to a 1975–1996 base period. Changes in relative humidity, especially dryingover much of the West, are projected to increase the number of days of high fire danger (based on the energy release component (ERC) index) at least through the year 2089 in comparison to the base period. The regions most affected are the northern Rockies, Great Basin and the Southwest –regions that have already experienced significant fire activity early this century. In these regions starting around the year 2070, when the model climate CO2 has doubled from present-day, the increase in the number ofdays that ERC (fuel model G) exceeds a value of 60 is as much as two to three weeks. The Front Range of the Rockies and the High Plains regions do not show a similar change. For regions where change is predicted, new fire and fuels management strategies and policies may be needed to address added climatic risks while also accommodating complex and changing ecosystems subject to human stresses on the region. These results, and their potential impact on fire and land management policy development, demonstrate the value of climate models for important management applications, as encouraged under the Department of Energy Accelerated Climate Prediction Initiative (ACPI), under whose auspices this work was performed. 相似文献
18.
V. N. Kryzhov 《Russian Meteorology and Hydrology》2012,37(5):291-297
Proposed is a method of downscaling of the global ensemble seasonal forecasts of air temperature computed using the SLAV model of the Hydrometcenter of Russia. The method is based on the regression and suggests a probabilistic interpretation of forecasts based on the assessment of uncertainty associated with the regression and model forecast ensemble spread. The verification of the method for 70 weather stations of North Eurasia using the rank probability skill score RPSS showed a significant advantage of downscaled forecasts over the forecasts interpolated from the model grid points. It is concluded that the use of the downscaling method is reasonable for the long-range forecasting of the station air temperature for North Eurasia. 相似文献
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Rudolf Br��zdil Monika B��l��nov�� Jaroslav Ro?novsky 《Theoretical and Applied Climatology》2011,104(1-2):71-81
Drought forecasting is a critical component of drought risk management. Identification of effective predictors is a major component of forecasting models. Sea surface temperature (SST) and sea level pressure (SLP) are relevant predictors for short- to long-term drought forecasts. However, these datasets are captured globally within a cell-wise network. This paper describes an approach to locate the most effective cells of the SST and SLP datasets using data mining. They are then applied as input to an adaptive neurofuzzy inference system (ANFIS) model to forecast possible droughts 3, 6, and 9?months in advance. Tehran plain was selected as the study area, and drought events are designated using the effective drought index (EDI). In another treatment, past values of the EDI time series were introduced to the ANFIS and the results compared with the previous findings. It was shown that R 2 values were higher for all cases applying the SST/SLP datasets. Additionally, the performance of SST/SLP datasets and the ANFIS model was assessed according to ??drought?? or ??wet?? classification, and it was concluded that more than 90% of the time the ANFIS model detected the drought status correctly or with only a one class error. 相似文献