江油市降水pH值的时间分布特征及控制对策

根据江油市2001～2009年的监测资料,首次分析江油市降水PH值的状况和变化.在降水酸碱类型的频率分布统计特征的基础上,探讨江油市降水pH值的季节分布特征及夏季酸雨的成因,并提出控制措施.     

基于人差错纠正能力的人因可靠性模型研究

根据人-机系统中人的操作行为具有时序性和差错可纠正性的特点,结合船舶舱室行为形成主因子,开展船舶舱室人因可靠性研究。以人因失误的时序性和差错纠正参数为基础,建立人-机系统中操作者行为模式和人因失误事件树模型。通过对人的差错纠正能力的分析,开展人因可靠性量化模型纠正理论研究。最后,以船舶舱室操作台的监控任务人因可靠性为例进行量化计算,定量评估操作人员执行任务的可靠度。     

秦皇岛地区气候资源及农业气候资源特征分析

利用近50 a秦皇岛气象资料,对该地区气候资源及农业气候资源特征进行了分析总结。结果表明:秦皇岛地区年降水量650～700 mm左右,呈减少趋势。全年80%保证率的降水量为425 mm,存在供需矛盾。蒸发量较降水量明显偏多,直接决定了该地区土壤在自然状态下绝大部分时段处于干旱状态。年平均气温10℃左右,呈上升趋势。平均年太阳辐射总量为5 154 MJ/m2,太阳辐射资源较丰富。秦皇岛地区农时较长,气温稳定通过10℃期间历时192 d,可以实行短生育期作物一年二熟或套作二熟。     

Simulated Impacts of Three Decadal Climate Variability Phenomena on Water Yields in the Missouri River Basin1

Mehta, Vikram M., Norman J. Rosenberg, and Katherin Mendoza, 2011. Simulated Impacts of Three Decadal Climate Variability Phenomena on Water Yields in the Missouri River Basin. Journal of the American Water Resources Association (JAWRA) 47(1):126‐135. DOI: 10.1111/j.1752‐1688.2010.00496.x Abstract: The Missouri River Basin (MRB) is the largest river basin in the United States (U.S.), and is one of the most important crop and livestock‐producing regions in the world. In a previous study of associations between decadal climate variability (DCV) phenomena and hydro‐meteorological (HM) variability in the MRB, it was found that positive and negative phases of the Pacific Decadal Oscillation (PDO), the tropical Atlantic sea‐surface temperature gradient variability (TAG), and the west Pacific warm pool (WPWP) temperature variability were significantly associated with decadal variability in precipitation and 2‐meter air temperature in the MRB, with combinations of various phases of these DCV phenomena associated with drought, flood, or neutral HM conditions. Here, we report on a methodology developed and applied to assess whether the aforementioned DCVs directly affect the hydrology of the MRB. The Hydrologic Unit Model of the U.S. (HUMUS) was used to simulate water yields in response to realistic values of the PDO, TAG, and WPWP at 75 widely distributed, eight‐digit hydrologic unit areas within the MRB. HUMUS driven by HM anomalies in both the positive and negative phases of the PDO and TAG resulted in major impacts on water yields, as much as ±20% of average water yield in some locations. Impacts of the WPWP were smaller. The combined and cumulative effects of these DCV phenomena on the MRB HM and water availability can be dramatic with important consequences for the MRB.     

Assessing the Impact of Areal Precipitation Input on Streamflow Simulations Using the SWAT Model1

Masih Ilyas, Shreedhar Maskey, Stefan Uhlenbrook, and Vladimir Smakhtin, 2011. Assessing the Impact of Areal Precipitation Input on Streamflow Simulations Using the SWAT Model. Journal of the American Water Resources Association (JAWRA) 47(1):179‐195. DOI: 10.1111/j.1752‐1688.2010.00502.x Abstract: Reduction of input uncertainty is a challenge in hydrological modeling. The widely used model Soil Water Assessment Tool (SWAT) uses the data of a precipitation gauge nearest to the centroid of each subcatchment as an input for that subcatchment. This may not represent overall catchment precipitation conditions well. This paper suggests an alternative – using areal precipitation obtained through interpolation. The effectiveness of this alternative is evaluated by comparing its simulations with those based on the standard SWAT precipitation input procedure. The model is applied to mountainous semiarid catchments in the Karkheh River basin, Iran. The model performance is evaluated at daily, monthly, and annual scales by using a number of performance indicators at 15 streamflow gauging stations each draining an area in the range of 590‐42,620 km². The comparison suggests that the use of areal precipitation improves model performance particularly in small subcatchments in the range of 600‐1,600 km². The modified areal precipitation input results in increased reliability of simulated streamflows in the areas of low rain gauge density. Both precipitation input methods result in reasonably good simulations for larger catchments (over 5,000 km²). The use of areal precipitation input improves the accuracy of simulated streamflows with spatial resolution and density of rain gauges having significant impact on results.     

陕西省精细化地质灾害气象预报预警研究

在黄土高原和秦巴山区地质灾害与降水相关特征分析基础上,介绍了陕西省气象台精细化地质灾害气象预报预警模型与业务系统.利用新一代多普勒天气雷达和自动气象站加密资料实现了综合雨量的精细估计,结合GIS地形地貌信息和历史灾害风险分析确定出降水影响系数后,通过计算指标量与灾害临界阈值判断实现了陕西省l 915个乡镇地质灾害的逐日...     

城市化对济南市汛期降雨特征的影响

在介绍济南市城市化发展水平及暴雨特性的基础上,选用济南市黄台桥、燕子山、东红庙、吴家铺和刘家庄雨量站1977-2007年汛期降雨资料,通过趋势线、距平统计、双累积曲线等方法,对济南市区汛期降雨量进行了统计分析,并对济南市城区、郊区的降雨时空特征进行对比研究。研究结果表明,城区多年汛期降雨量表现出较强的波动性,但整体上升趋势较为明显,尤其是改革开放早期的降雨量增长较为迅速。城市化对济南城区产生了较为明显的雨岛效应,城区比郊区降雨量增加约10%。城市化对降雨的频次以及雨型均造成了较大的影响,增加了各种降雨强度等级的降雨机率,城区比郊区的降雨机率增加10%以上,特别是暴雨以上的降雨场次增加了22%。     

一座南亚热带中富营养水库夏季浮游植物群落的稳态平衡分析

于2009年7月23日~9月12日(共8周)研究了广东省大沙河水库湖泊区表层5 m水柱浮游植物群落结构和演替过程及其环境影响因子.降雨明显分为二个阶段,前4周降雨丰富,后4周降雨稀少;水体的透明度与水温也相应地分为二个阶段,但营养盐水平没有明显的变化.平均N/P为33,而可溶解磷浓度很低,说明浮游植物的生长受磷的限制较为强烈.浮游植物种类分析中共检到藻类64种,生物量变化为0.95~2.03 mg L-1,主要由绿藻、甲藻和蓝藻组成.1~5周浮游植物的总生物量变化较大,后3周总生物量变化相对较小.在整个采样期间,光角角星鼓藻(Staurastrum muticum)为第一优势种,弯曲角星鼓藻藻(Staurastrum inflexum)为第二优势种(二者约占总生物量的70%);在1~5周第三个优势种的种类和生物量有较大的变化,6~8周第三优势种为飞燕角甲藻(Ceratium hirundinella)且前3个优势种的组成和生物量较稳定(共占到总生物量的80%以上),群落结构处于稳态平衡状态.降雨带来的干扰是影响浮游植物群落稳态平衡的主要因子.当降雨的干扰结束后,浮游植物之间通过1周左右的竞争,浮游植物群落达到稳态平衡.     

哈尔滨城市林业示范基地春季可燃物含水率动态研究

主要针对2011年冬季黑龙江省哈尔滨市地区降水过少而2012年春季极度干旱对森林可燃物含水率的影响进行研究。对在2011—2013年冬季反常气候影响下的黑龙江哈尔滨城市林业示范基地的樟子松、胡桃楸、白桦、蒙古栎林下可燃物含水率的动态变化进行了定点检测,并通过细致的分析发现随着气象条件的变化,不同森林可燃物含水率呈现出不同的变化趋势：樟子松林下可燃物含水率相比之下一直很高,胡桃楸林下可燃物含水率一直非常稳定,对环境条件的变化反映不太明显,而蒙古栎林下可燃物则处于中间,白桦林下可燃物对气象因子的变化最为敏感,上下波动很大。根据监测获得的数据对不同森林可燃物含水率和气象因子的关系进行了多元线性回归分析,并在符合一定条件的前提下建立了相对应的含水率预测模型,由于数据较少等原因,所得模型准确性有待验证,但是这也为哈尔滨城市林业示范基地森林含水率的预测奠定了基础。     

Impacts of Climate Change on Extreme Precipitation Events Over Flamingo Tropicana Watershed1

Abstract: Climate change, particularly the projected changes to precipitation patterns, is likely to affect runoff both regionally and temporally. Extreme rainfall events are expected to become more intense in the future in arid urban areas and this will likely lead to higher streamflow. Through hydrological modeling, this article simulates an urban basin response to the most intense storm under anthropogenic climate change conditions. This study performs an event‐based simulation for shorter duration storms in the Flamingo Tropicana (FT) watershed in Las Vegas, Nevada. An extreme storm, defined as a 100‐year return period storm, is selected from historical records and perturbed to future climatic conditions with respect to multimodel multiscenario (A1B, A2, B1) bias corrected and spatially disaggregated data from the World Climate Research Programme's (WCRP's) database. The cumulative annual precipitation for each 30‐year period shows a continuous decrease from 2011 to 2099; however, the summer convective storms, which are considered as extreme storms for the study area, are expected to be more intense in future. Extreme storm events show larger changes in streamflow under different climate scenarios and time periods. The simulated peak streamflow and total runoff volume shows an increase from 40% to more than 150% (during 2041‐2099) for different climate scenarios. This type of analysis can help evaluate the vulnerability of existing flood control system and flood control policies.