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利用9210传输的气象资料,选用国家气象中心T106和HLAFS数值预报产品中的要素作为火险天气因子,根据森林火险原理,建立了东营市森林火险天气等级预报系统. 相似文献
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东营市森林火险天气等级预报系统 总被引：2，自引：0，他引：2
利用9210传输的气象资料，选用国家气象中心T106和HLAFS数值预报产品中的要素作为火险天气因子，根据森林火险原因，建立了东营市森林火险天气等级预报系统。 相似文献
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利用林火资料和气象资料,通过建立概率模型模拟单因子对森林火险气象等级的单因子贡献度，然后通过四级判別得出综合模型，再根据不同季节植被因子对天气火险等级进行订正，最终得出森林火险气象等级。用此模型，对1981—2000年逐曰74个站进行了森林火险气象等级计算，形成文本文件和库文件；对每日的实时资料进行火险气象等级计算；根据T213数值预报产品，计算未来24小时的火险气象等级。全省31个站的火险等级在省台服务器上以MICAPS第三类数据格式存放或通过“黑龙江省短期森林火险气象等级顿报系统”调看。 相似文献
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应用红河州森林火险天气等级预报模式，对红河州1980年至2004年森林火灾与天气气候进行分析研究，研制适合红河州的森林火险天气等级预警预报系统，为公众提供更好的预报产品。 相似文献
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森林火灾严重威胁生态安全和国民经济,由于不同林地的气候以及可燃物存在差异,森林火险具有明显的区域性特征。因此,在考虑气象因子的基础上,将可燃物含水率引入小区域的森林火险指数的计算,对建立更精确的小区域森林火险等级标准和预报模型具有重要意义。本研究系统地分析了2013—2016年井冈山地区森林可燃物含水率与气象因子的分布频率及因子间的相互关系。通过主成分分析方法对所有因子进行降维处理,获得火险因子得分方程,并计算出2013—2016年井冈山地区逐日森林火险指数,进而构建火险等级划分和森林火险等级预报模型。结果表明:井冈山森林火险等级划分为5类,分别为低(火险值≤0.024)、较低(0.024火险值≤0.067)、高(0.067火险值≤0.167)、较高(0.167火险值≤0.232)、极高(火险值0.232)。基于BP神经网络模型构建了井冈山森林火险等级预报模型,预测精度可达96.4%。并利用2013—2017年卫星监测到的井冈山地区热源点数据对模型进行检验,预报准确率高达92.3%,表明该火险等级标准和预报模型能够满足井冈山地区日常防火业务需求。 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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森林火灾遍及全球，损失巨大。火险天气指数（FWI）是森林火灾预警和管理的有效工具。相对湿度（RH）是计算天气火险指数一个非常重要的参数。然而，由插值方法得到的RH在远离气象站点的地方往往存在很大的误差。因此，尝试利用MODIS遥感数据计算基于像元的高分辨率RH。MODIS的MOD07大气廓线产品，可以提供大气可降水量和地表气温数据。基于地面水汽压和大气可降水量的经验关系，利用MODIS数据计算了地表空气的相对湿度，平均绝对误差小于5％。结果表明，利用MODIS数据能简单而有效地计算地表空气的相对湿度，拓展了遥感技术在森林火险管理中的应用。 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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Forest fire danger projections in the Mediterranean using ENSEMBLES regional climate change scenarios 总被引：1，自引：1，他引：0
We present future fire danger scenarios for the countries bordering the Mediterranean areas of Europe and north Africa building on a multi-model ensemble of state-of-the-art regional climate projections from the EU-funded project ENSEMBLES. Fire danger is estimated using the Canadian Forest Fire Weather Index (FWI) System and a related set of indices. To overcome some of the limitations of ENSEMBLES data for their application on the FWI System—recently highlighted in a previous study by Herrera et al. (Clim Chang 118:827–840, 2013)—we used an optimal proxy variable combination. A robust assessment of future fire danger projections is undertaken by disentangling the climate change signal from the uncertainty derived from the multi-model ensemble, unveiling a positive signal of fire danger potential over large areas of the Mediterranean. The increase in the fire danger signal is accentuated towards the latest part of the transient period, thus pointing to an elevated fire potential in the region with time. The fire-climate links under present and future conditions are further discussed building upon observed climate data and burned area records along a representative climatic gradient within the study region. 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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Robust projections of Fire Weather Index in the Mediterranean using statistical downscaling 总被引：2，自引：2，他引：0
J. Bedia S. Herrera D. San Martín N. Koutsias J. M. Gutiérrez 《Climatic change》2013,120(1-2):229-247
The effect of climate change on wildfires constitutes a serious concern in fire-prone regions with complex fire behavior such as the Mediterranean. The coarse resolution of future climate projections produced by General Circulation Models (GCMs) prevents their direct use in local climate change studies. Statistical downscaling techniques bridge this gap using empirical models that link the synoptic-scale variables from GCMs to the local variables of interest (using e.g. data from meteorological stations). In this paper, we investigate the application of statistical downscaling methods in the context of wildfire research, focusing in the Canadian Fire Weather Index (FWI), one of the most popular fire danger indices. We target on the Iberian Peninsula and Greece and use historical observations of the FWI meteorological drivers (temperature, humidity, wind and precipitation) in several local stations. In particular, we analyze the performance of the analog method, which is a convenient first choice for this problem since it guarantees physical and spatial consistency of the downscaled variables, regardless of their different statistical properties. First we validate the method in perfect model conditions using ERA-Interim reanalysis data. Overall, not all variables are downscaled with the same accuracy, with the poorest results (with spatially averaged daily correlations below 0.5) obtained for wind, followed by precipitation. Consequently, those FWI components mostly relying on those parameters exhibit the poorest results. However, those deficiencies are compensated in the resulting FWI values due to the overall high performance of temperature and relative humidity. Then, we check the suitability of the method to downscale control projections (20C3M scenario) from a single GCM (the ECHAM5 model) and compute the downscaled future fire danger projections for the transient A1B scenario. In order to detect problems due to non-stationarities related to climate change, we compare the results with those obtained with a Regional Climate Model (RCM) driven by the same GCM. Although both statistical and dynamical projections exhibit a similar pattern of risk increment in the first half of the 21st century, they diverge during the second half of the century. As a conclusion, we advocate caution in the use of projections for this last period, regardless of the regionalization technique applied. 相似文献
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The use and development of bias correction (BC) methods has grown fast in recent years, due to the increased demand of unbiased projections by many sectoral climate change impact applications. Case studies are frequently based on multi-variate climate indices (CIs) combining two or more essential climate variables that are frequently individually corrected prior to CI calculation. This poses the question of whether the BC method modifies the inter-variable dependencies and eventually the climate change signal. The direct bias correction of the multi-variate CI stands as a usual alternative, since it preserves the physical and temporal coherence among the primary variables as represented in the dynamical model output, at the expense of incorporating the individual biases on the CI with an effect difficult to foresee, particularly in the case of complex CIs bearing in their formulation non-linear relationships between components. Such is the case of the Fire Weather Index (FWI), a meteorological fire danger indicator frequently used in forest fire prevention and research. In the present work, we test the suitability of the direct BC approach on FWI as a representative multi-variate CI, assessing its performance in present climate conditions and its effect on the climate change signal when applied to future projections. Moreover, the results are compared with the common approach of correcting the input variables separately. To this aim, we apply the widely used empirical quantile mapping method (QM), adjusting the 99 empirical percentiles. The analysis of the percentile adjustment function (PAF) provides insight into the effect of the QM on the climate change signal. Although both approaches present similar results in the present climate, the direct correction introduces a greater modification of the original change signal. These results warn against the blind use of QM, even in the case of essential climate variables or uni-variate CIs. 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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重庆市森林火险变化特征及气象条件分析 总被引：1，自引：0，他引：1
利用重庆市34个气象站1961-2007年逐日气象观测资料以及同期NECP/NCAR逐月再分析数据,根据森林火险环境气象指数的定义,研究了重庆市森林火灾变化特征,并对春季和盛夏高森林火险等级下的典型年份的大气环流特征进行了分析。结果表明：重庆林火次数具有明显的年、季、月、日变化特征,盛夏（7-9月）和春季（2-4月）为2个高峰期,其林火次数占全年林火总数的78%,其中8月最多（占全年林火总数的18%）,午后是森林火灾多发时段;春季重庆市高森林火险的大气环流特征表现为：乌拉尔山、贝加尔湖和鄂霍茨克海地区500 hPa位势高度偏低,四川盆地高度场偏高,冷空气在中高纬地区堆积,天气活动主锋区偏北;盛夏重庆市高森林火险的环流特征为：巴尔喀什湖和鄂霍茨克海地区500 hPa位势高度显著偏低,朝鲜半岛位势高度显著偏高,西太平洋副热带高压位置偏北。 相似文献