郑州市冬季采暖期气候变化特征及节能潜力分析     

刘和平  代佩玲  郭学峰  张青珍  周志刚 《河南气象》2009,(3):59-63

利用郑州市1951—2007年日平均气温资料,按照国家采暖规范从气候角度上确定了符合郑州特点的采暖初终日,较规定的初、终日（11月15日至次年3月15日）有明显推迟和提前的趋势,并分析了采暖期长度及采暖期的气候变化特征,结果表明：进7．90年代特别是21世纪初采暖期明显缩短,平均较80年代缩短了14d左右。在此基础上研究了近57a来采暖期气候条件的变化,并通过构建采暖强度、采暖指数指标,讨论这种变化对能源消耗和环境保护的影响,从科学角度提出节能的可能性。  相似文献   

郑州市冬季采暖期气候变化特征及节能潜力分析     

刘和平  代佩玲  郭学峰  张青珍  周志刚   《气象与环境科学》2009,32(3):59-63

利用郑州市1951—2007年日平均气温资料,按照国家采暖规范从气候角度上确定了符合郑州特点的采暖初终日,较规定的初、终日（11月15日至次年3月15日）有明显推迟和提前的趋势,并分析了采暖期长度及采暖期的气候变化特征,结果表明：进7．90年代特别是21世纪初采暖期明显缩短,平均较80年代缩短了14d左右。在此基础上研究了近57a来采暖期气候条件的变化,并通过构建采暖强度、采暖指数指标,讨论这种变化对能源消耗和环境保护的影响,从科学角度提出节能的可能性。  相似文献   

Attribution analyses of potential evapotranspiration changes in China since the 1960s   总被引：10，自引：0，他引：10  

Yunhe Yin  Shaohong Wu  Gang Chen  Erfu Dai 《Theoretical and Applied Climatology》2010,101(1-2):19-28

This paper focuses on the primary causes of changes in potential evapotranspiration (ET_o) in order to comprehensively understand climate change and its impact on hydrological cycle. Based on modified Penman-Monteith model, ET_o is simulated, and its changes are attributed by analyzing the sensitivity of ET_o to influence meteorological variables together with their changes for 595 meteorological stations across China during the period 1961–2008. Results show the decreasing trends of ET_o in the whole country and in most climate regions except the cold temperate humid region in Northeast China. For China as a whole, the decreasing trend of ET_o is primarily attributed to wind speed due to its significant decreasing trend and high sensitivity. Relative humidity is the highest sensitive variable; however, it has negligible effect on ET_o for its insignificant trend. The positive contribution of temperature rising to ET_o is offset by the effect of wind speed and sunshine duration. In addition, primary causes to ET_o changes are varied for differing climate regions. ET_o changes are attributed to decreased wind speed in most climate regions mainly distributed in West China and North China, to declined sunshine duration in subtropical and tropical humid regions in South China, and to increased maximum temperature in the cold temperate humid region.  相似文献   

河南省黄淮气旋暴雨的天气特征及个例诊断   总被引：4，自引：2，他引：2  

梁钰  王新敏  邵宇翔  代佩玲  徐泉丽 《气象与环境科学》2010,33(1):24-29

通过对1990-2001年6-8月影响河南省的18个黄淮气旋暴雨个例进行统计得知:影响河南省的黄淮气旋暴雨6月最多,7月次之,8月最少。黄淮气旋暴雨产生有两个源地,一个在河南省三花间略偏南一带,另一个在河南省南部和湖北的交界处,气旋的形成与两地向东开口的喇叭口地形有关。黄淮气旋暴雨发生前24-12 h,地面图上影响系统可分为西路冷空气影响型和倒槽顶部发展型两种;高空图上,河南多受高压脊控制,700 hPa影响系统有"人"字型切变和低槽型两种,但与地面影响系统没有直接对应关系。为了进一步揭示黄淮气旋暴雨的发生机理,利用NCEP再分析资料,对2007年7月12-15日黄淮气旋引发的暴雨天气过程进行了诊断分析,结果表明:黄淮气旋暴雨的发生、发展是大气斜压性强烈发展的结果,500 hPa高空急流和700 hPa低涡的移动方向对地面气旋的移动有引导作用。  相似文献   

秦岭地区气溶胶对地形云降水的抑制作用   总被引：12，自引：3，他引：9  

戴进  余兴  Rosenfeld Daniel 《大气科学》2008,32(6):1319-1332

以华山站为影响站, 周围的西安、渭南和华阴作为对比站, 通过影响站与对比站降水之比——地形强化因子(Ro)的变化趋势以及Ro与能见度关系的分析, 定量研究了秦岭地区气溶胶对地形云降水的抑制作用。Ro的演变分析表明: 有观测以来Ro逐年递减, 减幅为14%～20%, 即影响站与对比站相比降水量减少了14%～20%; Ro的减少趋势与能见度递减、气溶胶递增相吻合, 说明气溶胶的增加抑制了地形云降水。Ro的递减主要是减少了中小雨 (日雨量小于30 mm) 的天数, 这种影响对浅薄的生命期较短的地形云降水作用更明显, 对于华山站, 30 mm以下的降水都会受到入云气溶胶的抑制作用, 而西安站为5 mm以下, 入云气溶胶浓度越高, 就有越厚的降水云受气溶胶影响而抑制降水; 在以动力强迫抬升为主的春秋季, 气溶胶抑制华山地形云降水20%左右, 最大可达25%; 在热对流条件下, 气溶胶对地形云和对平原地区云的抑制作用基本相当。不同风速风向下Ro的变化趋势表明, Ro递减随风速增大而加快, 迎风向 (240°～30°) 大风 (≥5 m/s) 时减少降水超过30%。由Ro与能见度关系的定量分析发现, 当能见度在14 km时Ro为1.8左右, 随着能见度的降低Ro逐渐减小, 当能见度小于8 km时,R0约为1.2, 减小了30%左右; 华山对于华阴的Ro与能见度呈线性关系, 相关系数达0.81。最后, 根据研究结果归纳出气溶胶抑制秦岭地区地形云降水的初步物理模型。  相似文献   

一个动态植被模型在欧洲森林碳水循环模拟中的适应性评估研究   总被引：1，自引：0，他引：1  

毛嘉富  王斌  戴永久 《大气科学》2008,32(6):1379-1391

对动态全球植被模型M-SDGVM (Modified Sheffield Dynamic Global Vegetation Model), 在1996～1998年15个欧洲森林通量站碳通量和水汽通量的季节和年际变化进行模拟和评估研究, 总的来说, 模型能够合理再现各个站点春、 夏季节碳的吸收, 秋、 冬季节碳的释放, 以及水汽释放的季节变化趋势, 其中, 对水汽通量的模拟更为理想。对模型的上述适应性评估研究表明, 改进后的M-SDGVM有能力研究不同气候条件下欧洲森林生态系统碳、 水循环过程及其响应机制, 但是, 模型对部分站点的模拟仍存在不确定性, 通过对这些偏差及其可能的产生机理进行分析, 有助于模型的进一步发展和应用研究。  相似文献   

河南大风灾害分布特征及成因分析   总被引：1，自引：1，他引：0  

刘和平  代佩玲 《气象与环境科学》2008,31(Z1)

本文利用全省1961-2006年的大风天气资料和大风灾情资料,对大风灾情发生的地理分布特征,月、季、年的时间变化特征进行统计分析,并对其成因作了进一步研究,结果发现,自20世纪80年代开始,大风灾情日数年际变化大幅度增加,大风日数与大风灾情日数的地理分布基本一致,大风灾情日数季节变化明显.  相似文献   

The Origin of the Element Eu in Extremely Metal-poor Halo Stars     

Jun-an Dai  Qiu-he Peng 《Chinese Astronomy and Astrophysics》2009

The fast neutron capture process (the r-process) occurs in the neutron-rich circumstance. However its concrete physical environment is not very clear. With recent progress in observations, many extremely metal-poor halo stars have been discovered. They have two characteristics: one is the overabundance of fast neutron elements with the relative abundance consistent with that of the sun; the other is that fast neutron element contents in stars at the same metal abundance have a very large dispersion. This provides a particular way to study the origin of the r-process. Simulation was used to study the galaxy's evolution process and the resulting dispersion of fast neutron nuclide contents in stars. The model of galaxy evolution obtained in this way not only contains spontaneous star formation in the gas region, but also includes the star formation excited by the supernova explosion. It is shown from our results that the supernovae at the low mass end should be the place producing the fast neutron nuclides. In addition, it is also shown that the non-uniformity of the galaxy evolution caused by the supernova explosion is not enough to explain the observed dispersion of fast neutron element contents in halo stars. This problem should be further studied.  相似文献   

The origin of refractory minerals in comet 81P/Wild 2     

Miaofang Chi  Hope A. Ishii  Steven B. Simon  John P. Bradley  Zurong Dai  David Joswiak  Nigel D. Browning  Graciela Matrajt 《Geochimica et cosmochimica acta》2009,73(23):7150-7161

Refractory Ti-bearing minerals in the calcium-, aluminum-rich inclusion (CAI) Inti, recovered from the comet 81P/Wild 2 sample, were examined using analytical (scanning) transmission electron microscopy (STEM) methods including imaging, nanodiffraction, energy-dispersive spectroscopy (EDX) and electron energy loss spectroscopy (EELS). Inti fassaite (Ca(Mg,Ti,Al)(Si,Al)₂O₆) was found to have a Ti³⁺/Ti⁴⁺ ratio of 2.0 ± 0.2, consistent with fassaite in other solar system CAIs. The oxygen fugacity (logf_O2) of formation estimated from this ratio, assuming equilibration among phases at 1509 K, is −19.4 ± 1.3. This value is near the canonical solar nebula value (−18.1 ± 0.3) and in close agreement with that reported for fassaite-bearing Allende CAIs (−19.8 ± 0.9) by other researchers using the same assumptions. Nanocrystals of osbornite (Ti(V)N), 2–40 nm in diameter, are embedded as inclusions within gehlenite, spinel and diopside in Inti. Vanadium is heterogeneously distributed within some osbornite crystals. Compositions range from pure TiN to Ti_0.36V_0.64N. The possible presence of oxide and carbide in solid solution with the osbornite was evaluated. The osbornite may contain O, but C is not present at detectable levels. The presence of osbornite, likely a refractory early condensate, together with the other refractory minerals in Inti, indicates that the parent comet contains solids that condensed closer to the proto-sun than the distance at which the parent comet itself accreted. The estimated oxygen fugacity and the reported isotopic and chemical compositions are consistent with Inti originating in the inner solar system like other meteoritic CAIs. These results provide insight for evaluating the validity of models of radial mass transport dynamics in the early solar system. The oxidation environments inferred for the Inti mineral assemblage are inconsistent with an X-wind formation scenario. In contrast, radial mixing models that allow accretion of components from different heliocentric distances can satisfy the observations from the cometary CAI Inti.  相似文献   

Assessment of global meteorological,hydrological and agricultural drought under future warming based on CMIP6          下载免费PDF全文

Jianxin Zeng  Jiaxian Li  Xingjie Lu  Zhongwang Wei  Wei Shangguan  Shupeng Zhang  Yongjiu Dai  Shulei Zhang 《大气和海洋科学快报》2022,15(1):49-55

在全球变暖背景下,分析和预测干旱的变化趋势和传播规律对于区域生态环境安全和灾害管理具有重要意义.本文基于第六次国际耦合模式比较计划(CMIP6),分析了SSP2-4.5和SSP5-8.5两种变暖情景下的气象(标准化降水指数SPI和标准化降水蒸发指数SPED,水文(标准化径流指数SRI)和农业(标准化土壤水分指数SSI)...  相似文献