Predicted changes in fire weather suggest increases in lightning fire initiation and future area burned in the mixedwood boreal forest

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.     

Assessing the impact of weather and climate in Australia

Weather and climate have a significant impact on the Australian society and environment. While the impacts of major changes in the Australian climate likely to occur from the enhanced greenhouse effect have been reported in the literature fewer studies have addressed the impact of the climate's natural variability. Ways in which weather and climate and its variability impact on the decision making process are described and methods available to assess the sensitivity of the economy and the natural environment are also presented. Methods which are being developed to determine the value of weather and climate information to decision makers are briefly described. The El Niño Southern Oscillation is a strong contributor to the variability of the Australian climate. It is used to illustrate the impact of climate variability on both the economy and natural environment of Australia. Finally, the extent to which there is political awareness of the impact of climate variability on the Australian society and environment is briefly examined.     

江西省天气预报员现状调查分析与对策建议

随着研究型业务和智能网格预报技术的不断深入,天气预报员的作用也将发生较大调整或转型.文中采用问卷调查方式,围绕学历、职称、预报业务与科研等方面总结了江西省、市、县三级预报员的现状,分析了当前预报员在业务发展中存在的问题与不足,提出了推进预报业务流程改革,进一步优化预报员队伍,坚持科技创新与研究型业务建设,加强团队建设与预报员岗位培训等优化人才队伍的对策建议.     

延安市森林火险天气分级预报方法

通过对延安市1989—2002年森林火灾资料的综合分析，发现当地火灾多发生在2—4月，火灾多发时段为每日12—14时，火灾类型多为地表火，引起火灾原因多为人为原因，占95％以上。分析森林火灾对应的气象资料，总出以连续无降水日数、最高气温、最小相对湿度三要素建立的分级火险天气预报方法结。业务试运行表明：该方法对高危火险天气有较好的预报效果，对林业部门森林防火指挥有一定参考价值。     

秋季林火成因及人工增雨效果分析

针对爱辉区2001年秋季森林大火，分析其成因，提出了人工增雨的防灾手段，并对其效果及发展前景进行了分析。     

The stochastic weather model in the system of deterministic and stochastic modeling of runoff and nutrient load

The estimation is carried out of the distribution functions of annual runoff and nutrient load on the Russian part of the Gulf of Finland (the Baltic Sea) formed by different pollution sources. The stochastic weather model is used for the estimation.     

用方差分析法作中长期预报的改进

采用一元回归方法统计历年各月（旬）的气象要素资料,消除了季节的差异和气候变化的影响,进行标准化处理后,使不同月或旬之间的数据具有可比性。并将标准化数据按时间顺序排列,作为原始序列进行方差分析,提高了拟和率和预报确率。     

暴雨过程形成的天气气候条件分析

分析了嫩江、松花江流域降水异常偏多和暴雨频繁发生的天气气候条件.指出导致1998年嫩江、松花江流域发生特大洪水的环流特征是鄂霍茨克阻塞高压偏强、少动,形成长时间维持的阻塞形势;这种形势阻挡西部移来的低压槽,使东北冷涡停留在110～120°E不能东移.之所以会连续出现暴雨、大暴雨,归纳起来有以下天气特点:①亚洲中高纬度地区阻塞形势异常稳定;②长时间受东北冷涡控制;③西太平洋副热带高压短时间北进,且与东亚阻塞高压同位相叠加,位置适中;④盛夏影响北方的季风短时强盛     

贵州精细化天气预报业务试验

根据贵州天气气候特点,以贵州省中尺度数值预报模式(MM5)为基础,以地理信息系统GIS为工具,对贵州精细化天气预报进行业务试验,制作贵州空间分辨率为1Km,时间分辨率为1h的温度预报,从而提高天气预报服务的能力,为贵州经济建设及社会的发展作贡献.     

夏季湖北电网气象敏感负荷预测模型研究

利用2009-2010年湖北电网日用电负荷资料和气象资料,提出了基于电网负荷的分解算法,将电网日最大负荷分解为基础负荷与气象敏感负荷2个主要分量.其中,气象敏感负荷与气温、相对湿度及风速的综合气象敏感负荷条件指数相关.提出了基于权重指数的湖北省面平均气象敏感负荷条件指数的算法.利用相关比法,分析了湖北省气象敏感负荷与面均气象敏感负荷条件指数的非线性关系.基于均方偏差最小原理和非线性最小二乘法,建立了夏季湖北电网气象敏感负荷与面均气象敏感负荷条件指数的多项式预测关系模型.经2010年9月模型应用检验表明,预测平均误差低于6％.该模型可用于夏季湖北省电力专业气象服务工作.     

Projected future changes in synoptic systems influencing southwest Western Australia

Rainfall in the southwest of Western Australia (SWWA) is sensitive to shifts in the hemispheric scale circulation due to its location at the northward extent of the influence of mid-latitude fronts. A step-drop in the 1970s to a new winter rainfall regime has caused great concern for water users in the region. The synoptic systems at the height of winter in the latter half of the 20th century over this region have been described in Hope et al. (Clim Dyn, 2006) using a self-organising map, and in this study the projected future shifts in those systems has been examined. Bounds are placed on the possible responses by examining a number of different models and, into the future, two scenarios at the upper (SRES A2) and lower (SRES B1) limits of plausible human induced emissions. Rainfall taken directly from the models captures the rainfall decline in the 1970s, and, although it is not as large as observed in any one model, all the models express a decline, which is a very strong result. Into the future the rainfall decline is dramatic. The scenario at the upper bound of emissions, where atmospheric concentrations of greenhouse gases continue to rise strongly, shows a rainfall decline right through to the end of the century. The shift in synoptic systems for most models is to far fewer troughs and more high pressure systems across the region. One model exhibits a different signature, with a shift to more systems with a zonal structure. The fact that there is a rainfall decline shown by all models, yet the synoptic changes are different, highlights how sensitive SWWA rainfall is to the different responses of climate models to increasing greenhouse gases. In the B1 scenario, the concentrations rise only slowly in the second half of the century and the shift is still to drier conditions, but it is not as striking. These results show that increasing concentrations of greenhouse gases lead to increasingly dry conditions in SWWA, and as the atmospheric concentrations rise, the synoptic response intensifies.     

2003年冬末春初长时间高危火险

分析了2003年2月15～3月4日的连续晴、热高危火险天气过程,此次过程是由异常强大的热低压、低空西南急流共同影响所引发的,并对数值预报产品在预报中的应用作了仔细分析,提出了数值预报产品的850hPa温度趋势及地面气压场可作为未来5～7d天气冷、暖的主要预报依据.     

四川地区一次特大暴雨天气过程分析

利用四川省加密气象站逐时降水资料、FY-2G卫星TBB产品及NCEP/NCAR的1°×1°逐6 h再分析资料,对2020年8月15—18日四川地区的一次特大暴雨天气过程进行诊断分析。结果表明：此次过程具有降水强度大、范围广、持续时间长、夜雨特征明显等特征。高空影响槽东移叠加在低空低涡之上,为强降水过程发生发展提供了有利的环流背景和天气尺度动力抬升条件;西太平洋副热带高压（以下简称“副高”）稳定少动是强降水过程长时间维持的主要原因。孟加拉湾低涡槽前西南暖湿气流与副高外围偏南暖湿气流共同为此次强降水过程提供了充足的水汽。中尺度对流系统强烈发展是造成强降水的主要原因,云图TBB≤-52℃的冷云区和TBB等值线梯度极大值区与强降水落区对应关系较好,可为强降水监测预警工作提供参考。     

安龙"4.15"瓦斯爆炸与天气条件分析

煤矿井内瓦斯爆炸需要具备一定条件：井内存在毒瓦斯、并有相当的浓度，有触发火源，环境气象要素差（压、温、湿、通风等）。通过安龙“4．15”瓦斯爆炸前天气及气象要素分析，为研究煤矿瓦斯爆炸提供“粗线条”式的气象因素参考，为减少煤矿安全生产事故提供参考。     

Future heat vulnerability in California, Part I: projecting future weather types and heat events

Excessive heat significantly impacts the health of Californians during irregular but intense heat events. Through the 21st century, a significant increase in impact is likely, as the state experiences a changing climate as well as an aging population. To assess this impact, future heat-related mortality estimates were derived for nine metropolitan areas in the state for the remainder of the century. Here in Part I, changes in oppressive weather days and consecutive-day events are projected for future years by a synoptic climatological method. First, historical surface weather types are related to circulation patterns at 500mb and 700mb, and temperature patterns at 850mb. GCM output is then utilized to classify future circulation patterns via discriminant function analysis, and multinomial logistic regression is used to derive future surface weather type at each of six stations in California. Five different climate model-scenarios are examined. Results show a significant increase in heat events over the 21st century, with oppressive weather types potentially more than doubling in frequency, and with heat events of 2?weeks or longer becoming up to ten times more common at coastal locations.     

Impact of climate and socioeconomic changes on fire carbon emissions in the future: Sustainable economic development might decrease future emissions

Fires and their associated carbon and air pollutant emissions have a broad range of environmental and societal impacts, including negative effects on human health, damage to terrestrial ecosystems, and indirect effects that promote climate change. Previous studies investigated future carbon emissions from the perspective of response to climate change and population growth, but the compound effects of other factors like economic development and land use change are not yet well known. We explored fire carbon emissions throughout the 21st century by changing five factors (meteorology, biomass, land use, population density, and gross domestic product [GDP] per capita). Compared to the historical period (2006–2015), global future fire carbon emissions decreased, mainly caused by an increase in GDP per capita, which leads to improvement in fire management and capitalized agriculture. We found that the meteorological factor has a strong individual effect under higher warming cases. Fires in boreal forests were particularly expected to increase because of an increase in fuel dryness. Our research should help climate change researchers consider fire-carbon interactions. Incorporating future spatial changes under diverse scenarios will be helpful to develop national mitigation and adaptation plans.     

贵阳龙洞堡机场一次雷雨冰雹天气过程分析

对原始常规资料运用最优插值的方法，对2003年4月18日贵阳龙洞堡机场发生的一次强雷雨冰雹天气过程进行客观诊断分析。结果表明：这次强对流过程是在大尺度辐合环流背景下，由500hPa高空槽东移和地面冷锋过境而触发的，贵阳地区持续的高温和西南低空急流水汽输送，为对流天气的发生提供了大量的不稳定能量和充沛的水汽条件，而垂直风的切变则使得对流发展更加旺盛，过程持续的时间更长。