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In the present study, the performances of the NWP models on two heavy rainfalls on 20 July and 22 August 2021 over Henan Province were investigated. The impacts of the water vapor transport to the extreme rainfall were further discussed. The results showed that the regional model system in the Guangzhou Meteorological Service generally showed high scores on the extreme rainfall over Henan. The maximum 24h accumulative rainfall by the 24h forecasts by the CMA-GD reached 556 mm over Henan Province. The 24-h and 48-h Threat Score (TS) of heavy rainfall reached 0.56 and 0.64. The comparisons of the Fraction Skill Score (FSS) verifications of the heavy rainfall by CMA-GD and CMA-TRAMS at the radium of 40km reached 0.96 and 0.87. The water vapor transport to the extreme rainfall showed that the vertically integrated water vapor transport (IVT) of the whole layer before the occurrence of the heavy rainfall exhibited a double-eyes distribution in case 7 · 20. The north eye over Henan reached the same magnitude of IVT as the typhoon eye (Cempaka) over south China. The IVT over the lower troposphere (<500 hPa) showed an overwhelming magnitude than the upper level, especially in the planetary boundary layer (<700 hPa). More practical technical needs to be developed to improve its performances on the forecasting of extreme rainfall, as well as more experiments need to be conducted to examine the effects of the specific terrain and physical schemes on the extreme rainfall. 相似文献
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为研究霾观测判识标准定量化对雾霾观测记录的影响,选取2006—2012年湖北省18个基准站、基本站和一般站三类国家级地面气象观测站的资料,对已记录和按照相对湿度判识标准统计的雾、轻雾和霾天数进行分析,结果表明:判识标准定量化将使霾的观测记录明显增多,轻雾和雾观测记录略有减少,霾和轻雾观测记录将更趋合理,就湖北省而言,相对湿度在80%~95%之间,应以轻雾和雾为主;通过定时观测时次的能见度、相对湿度,以及日天气现象记录,可以得到历年按照相对湿度判识标准统计的霾和轻雾天数,实现对历史资料序列的订正,形成判识标准改变前后均一化的月年资料序列。判识标准定量化后,不能机械的硬套判识指标,观测员仍需熟练掌握轻雾和霾以及其他视程障碍现象的成因和特征,避免相对湿度在霾观测判识标准上下波动、轻雾处于消散过程阶段,轻雾与霾的频繁转记。 相似文献
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The accurate detection of heavy metal-induced stress on crop growth is important for food security and agricultural, ecological and environmental protection. Spectral sensing offers an efficient and undamaged observation tool to monitor soil and vegetation contamination. This study proposed a methodology for dynamically estimating the total cadmium (Cd) accumulation in rice tissues by assimilating spectral information into WOFOST (World Food Study) model. Based on the differences among ground hyperspectral data of rice in three experiments fields under different Cd concentration levels, the spectral indices MCARI1, NREP and RH were selected to reflect the rice stress condition and dry matter production of rice. With assimilating these sensitive spectral indices into the WOFOST + PROSPECT + SAIL model to optimize the Cd pollution stress factor fwi, the dynamic dry matter production processes of rice were adjusted. Based on the relation between dry matter production and Cd accumulation, we dynamically simulating the Cd accumulation in rice tissues. The results showed that the method performed well in dynamically estimating the total amount of Cd accumulation in rice tissues with R2 over 85%. This study suggests that the proposed method of integrating the spectral information and the crop growth model could successfully dynamically simulate the Cd accumulation in rice tissues. 相似文献
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众多研究表明黄河源区受气候变化影响,土壤活动层逐渐下降。土壤温、湿度是陆面过程及地球系统中的重要物理量,它们通过影响地表能量和物质交换而影响大气环流和降水等。利用WRF（Weather Research and Forecasting）模式,选取2个典型年分别设计了2个控制试验和2个敏感性试验来探讨土壤初始状况变化对区域水循环的影响,通过再循环降水率定量描述不同气候背景下陆面对黄河源区水循环的影响,并尝试从环流角度进一步分析土壤初始状况改变对源区水循环影响的物理机制。结果表明：陆面对水循环的影响受大尺度环流背景场影响较大,较弱的环流背景下再循环降水率较强环流背景大5%左右。土壤初始状况对水循环要素有一定程度的影响。土壤初始温度升高/降低,水汽通量增多/减少,后期降水增大/减小。不同环流背景下,土壤记忆时间不同,在弱的环流背景下,土壤记忆时间要长,初始状况扰动可持续1～2个月。 相似文献
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利用沪渝高速公路恩施-宜昌路段恩施附近的三岔口大桥(海拔708 m)自动站监测2013年6—8月(夏季)及2013年12月至2014年2月(冬季)逐日逐时次气象要素资料,统计分析夏季、冬季路面温度与气温的变化特征及路面温度与气象因子的关系,基于逐步引入因子线性回归分析方法建立路面温度统计模型,并对模型的预报效果进行实验研究。结果表明:夏季路面最高温度受多种气象要素的影响,与日最高气温、日平均气温、前一日路面最高温度、前一日路面平均温度呈正相关,与相对湿度、24 h累计降水呈负相关。冬季路面最低温度与最低气温呈显著性相关。通过模型的效果实验,发现夏季路面最高温度用日最高气温、日最小相对湿度及前一天物理量建立的模型预报结果与实况的变化趋势最为接近;冬季路面最低温度用日最低气温、日最小相对湿度、日平均风速及前一天物理量建立的模型预报结果与实况的变化趋势最为接近。 相似文献
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便携式雷达现场测试和诊断移动平台是集雷达系统设备性能参数测试、故障诊断、维修保障等功能于一体的新型技术保障平台。该平台通过仪器仪表的集成、综合检测的流程化、应用软件和配套工装的开发,可解决雷达站缺乏系统的测试维修与诊断手段、故障诊断与维修主要依靠厂家、远程测试与诊断指导的技术手段和能力薄弱、台站配备的仪器仪表单一等主要业务问题。该平台对雷达站现场开展雷达系统设备的故障检测、测试分析、维修指导等工作具有重要的现实意义,能给雷达现场测试维修、故障诊断及快速恢复系统正常运行提供便利和帮助。 相似文献
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Renewable energy sources, especially wind power, were believed to be able to slow down global warming; however, evidence in recent years shows that wind farms may also induce climate change. With the rapid development of wind power industry, the number of wind farms installed in mountains has gradually increased. Therefore, it is necessary to study the impact of wind farms in mountainous areas on local climate. The Suizhou and Dawu wind farms in northern Hubei Province were chosen for the present study on the impact of wind farm operations on the local climate in mountainous areas. The mesoscale meteorological numerical model Weather Research and Forecasting Model (WRF) and the Fitch model, together with turbulence correction factor, were used to simulate wind farm operations and study their effects on local climate. The results showed the characteristics of wind speed attenuation in mountainous wind farms: the amplitude and range of wind speed attenuation were stronger in the nighttime than in the daytime, and stronger in summer than in winter. The surface temperature increased and became more significant in summer. However, a cooling variation was observed above the surface warming center. The height of this center was higher in the daytime than it was in the nighttime. The latent heat flux in the wind farms decreased at night, accompanied by an increase in sensible heat flux. However, these changes were not significant. Some differences were observed between the impact of wind farms on the climate in the plains and the mountains. Such differences are more likely to be related to complex terrain conditions, climate conditions, and the density of wind turbines. The present study may provide support for the development and construction of wind farms in mountainous areas. 相似文献
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利用湖北省内黄石等11个国家气象站2005—2007年自动观测、人工观测同期分钟雨量数据,分别逐年滑动提取5、10、15、20、30、45、60、90、120、150、180 min这11个短历时的最大雨量值及开始时间。从时间偏差、雨量偏差、设定时间偏差范围三方面分析两种观测下的短历时雨量差异,并利用分析结果建立了自动观测、人工观测短历时雨量关系方程。结果表明:(1)从自动观测、人工观测分钟数据中提取短历时雨量时,对降水过程判断基本一致,选取同一降水过程,各降水历时70%以上样本数据的开始时间偏差基本在0~10 min。(2)各历时自动观测、人工观测短历时雨量提取结果比较吻合,两者雨量偏差范围在±10%以内的情况占样本总数的68.6%,且自动较人工观测短历时雨量偏大的情况居多,占样本总数的60.9%。(3)设定时间偏差范围为0~5 min,自动观测、人工观测短历时雨量提取结果非常吻合。将时间偏差缩小到0~2 min,吻合度进一步提高。(4)分别建立了11个降水历时自动观测、人工观测短历时雨量关系方程,两套数据相关系数达到0.92以上,自动观测、人工观测短历时雨量变化非常一致。 相似文献
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分析太阳辐射状况是光伏电站项目评估的重要举措,针对分析过程中涉及的各类数据计算和可视化查询,设计实现了省级太阳辐射模拟可视化查询平台。平台根据主要功能划分为数据处理子系统和查询分析子系统,数据处理子系统采用MODIS云量数据、气象站与辐射站历年数据,计算生成具有共同基准的多要素辐射相关数据;查询分析子系统将地图影像与实际数据结合显示,让数据模拟更直观、数据分析更合理。数据处理子系统使用了Qt进行开发,查询分析子系统使用ArcGIS Desktop、ArcGIS Server和MySQL数据库软件,结合Dojo、C#、ASP.NET MVC技术进行开发。使用Python作为“粘合剂”连接两个子系统,让数据成图和发布自动化。平台集数据处理和可视化查询为一体,能够以1 km×1 km的精度模拟分析出省级范围太阳辐射的分布情况,为光伏数据分析和光伏电站建设工作提供及时、有效、科学的技术支撑。 相似文献