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利用山东省沿海测风塔70 m高度完整1 a的观测资料计算分析风能资源参数特征.结果表明：山东沿海地区平均风速与有效风功率密度分布特征相似,烟台沿海区域平均风速及有效风功率密度最大分别达到6.7 m/s、463.5 W/m2,沿海北部地区风能资源最为丰富,日照地区最少;受海陆风作用,春季风能资源最好,其次是冬季,夏季最差,风速最大值基本出现在14-16时;年有效风能时数及百分率分别为7 440 h、85%;风能密度分布基本以偏北或偏南方位较大.沿海区域风能资源分布特征与长年代评估结果及数值模拟结果基本一致. 相似文献
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河西走廊东部风能资源分布特征及开发利用 总被引：8，自引：1，他引：7
利用河西走廊东部5站1971-2004年逐日4次定时地面气象观测资料和2005-2006年地面自动气象观测站逐小时气象观测资料,用统计学方法分析了该区域近地面风速及风能的演变和分布。结果表明：河西走廊东部环境风速的气候变化比较稳定,但探测环境变化较大的站点风速下降十分明显;风能分布具有山区最大、沿河西走廊峡管和荒漠地带次之、中部武威绿洲盆地最小的地域分布特点;南部山区年平均风速均大于等于3．5m·s^-1、全年各月平均风速均大于等于3．0m·s^-1,且全年风向、风速跃变小,习平均有效风能时数大于等于13．9h,年平均有效风能时数大于等于5000h,因此具有较大的风能开发利用价值;北部荒漠和沙漠地区年平均风速为2．7m·s^-1,一年中3～7月风速较大,日平均有效风能时数为8．7h,年平均有效风能时数为2913h,年平均有效风能密度为82．7W·m^-2,具有季节性风能开发利用价值;位于绿洲盆地的凉州区由于各项风能参数均较小,不适宜进行风力发电。根据河西走廊东部地域和气候特点,分析了风能开发利用前景。 相似文献
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WRF模式对中国夏季降水的动力降尺度模拟研究 总被引：4，自引：3，他引：1
采用NCEP的FNL再分析资料驱动WRF模式,对中国10 a(2000—2009年)夏季降水进行双重动力降尺度(双重嵌套)模拟,将子、母区域模拟结果和观测进行对比,以检验双重动力降尺度对中国夏季降水模拟的"增值"能力。结果表明:单重动力降尺度(单重嵌套)方法能较好模拟出中国10 a夏季平均降水的空间分布,对季风雨带"北跳"特征模拟较好,但模拟降水具有系统性正偏差。在母区域的强迫下,双重动力降尺度模拟的降水分布与单重动力降尺度相比,没有发生根本性变化。但由于子区域的分辨率要高于母区域,双重动力降尺度比单重动力降尺度能提供更多有价值的降水细节。双重动力降尺度的这种"增值"能力存在地域依赖性,在华南地区和江淮地区,双重动力降尺度模拟出的降水分布、量值和逐日演变都要好于单重动力降尺度。但在华北地区,双重动力降尺度没有表现出明显的"增值"。 相似文献
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《高原气象》2021,40(4):919-931
谱逼近方法和变分资料同化方法都是提高动力降尺度模拟效果的有效手段,其中谱逼近方法通过引入分析或再分析资料来订正长时间连续积分造成的大尺度偏差问题,其模拟输出有望为变分同化提供质量较好的背景场。为此,本文通过WRF模式对2015年夏季秦巴山区实施水平分辨率为5 km的短期气候动力降尺度模拟,探讨在谱逼近方法的基础上利用三维变分(3DVar)同化方法同化地面观测资料的降尺度模拟效果,以期为获取复杂地形下高精度的高分辨率降尺度数据集提供一种有效途径。结果表明,在动力降尺度过程中使用谱逼近方法能够改善2 m温度、10 m风速和降水的模拟结果。只同化地面观测资料对模拟的2 m温度和10 m风速有明显改善,但对降水模拟有负作用。谱逼近方法和地面资料同化方法的结合使用能够得到2 m温度、10 m风速的最佳模拟效果,对降水的模拟结果也优于只同化地面观测资料的试验效果。使用谱逼近方法能够有效地对风场和水汽场做出合理调整,这是其降水模拟精度提高的原因之一。 相似文献
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风能资源评估技术方法研究 总被引：36，自引：0，他引：36
全球性的能源危急和气候变化,驱动了风力发电在世界范围内迅速发展,搞清风能资源是大规模发展风电的关键步骤。文中首先回顾了近10年来开展风能资源评估的技术方法发展历程,阐述了数值模拟技术的应用对风能资源评估技术方法的发展所起的重要作用。风能资源的数值模拟可以给出风能利用高度上的风能资源分布;可以模拟出基于气象站观测资料的统计分析无法找到的风能资源;可以弥补海上测风资料不足的缺陷,进行海上风能资源的评估。文中运用中国气象局的风能资源数值模式系统地对江苏省和青海省的风能资源分布进行了高分辨率的数值模拟,并采用气象站观测资料对数值模拟结果进行了检验,结果表明数值模拟可以较准确地模拟区域风能资源的分布趋势,但在风速值大小会有系统性偏差,需要有测风塔观测资料对数值模拟结果进行订正,说明了数值模拟技术与风能资源测量相结合是风能资源评估的有效技术手段。最后对中国风能资源数值模拟技术的发展进行了展望,表明了中国风能资源的开发利用对自主发展小尺度数值模式的迫切需求。 相似文献
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利用空间分辨率为5km的广西智能网格降雨量预报产品以及桂南区域自动气象站降雨量实况资料,采用最邻近点法、双线性插值、双三次插值和统计降尺度方法,研究和评估空间分辨率在1km的格点降雨量插值预报释用技术。结果表明:(1)对于分辨率较高的智能网格预报产品,最邻近点法、双线性插值和双三次插值的预报效果无明显差异,其中最邻近点法的ETS评分和预报偏差略好于其它两种方法;(2)采用一元线性回归的统计降尺度方法比其它3种方法的降水预报能力高,并可以提高强降水的预报评分,对构造更高分辨率的网格预报产品具有一定参考作用。 相似文献
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动力降尺度被广泛的应用于区域气候降尺度工作中,用来制作高时空分辨率的区域气候场。本文采用WRF模式的张弛方法对美国第三代再分析资料(CFSR)进行了动力降尺度,使用观测张弛法同化自动气象站观测资料的同时,采用分析张弛法同化了大尺度再分析资料。选取辽宁省7月和10月作为夏季和秋季代表月份,分析不同降尺度方案对地面要素的模拟能力,发现使用张弛方法在区域气候降尺度过程中,可以明显提高地面2 m温度、10 m风速和2 m相对湿度的模拟能力,其中使用张弛算法同化大尺度的再分析资料和观测资料的准确度最高,相较于控制试验,7月和10月温度、风速和相对湿度的平均均方根误差分别减少了25%、39%和30%。 相似文献
11.
《大气与海洋》2013,51(1):63-78
Abstract Although the Mesoscale Community Compressible (MC2) model successfully reproduces the wind climate (for wind energy development purposes) of the Gaspé region, equivalent simulations for the steep mountainous southern Yukon have been unsatisfactory. An important part of the problem lies in the provision of suitable boundary conditions in the lower troposphere. This paper will describe an alternative provision of boundary conditions to the MC2 model based partly on standard National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) Reanalysis statistics, however, with modified lower tropospheric conditions based on local radiosonde measurements. The MC2 model is part of the AnemoScope wind energy simulation toolkit which applies statistical‐dynamical downscaling of basic large‐scale weather situations (i.e., the NCEP/NCAR Reanalysis) to simulate the steadystate wind climate of a complex region. A case study summarized here imposes a typical mean winter temperature inversion on the boundary conditions to reduce downward momentum transfer in the MC2 model over the Whitehorse region. In conjunction with this step, the geostrophic wind at the boundaries is held constant (with height) in speed and direction, based on the (observed) dominant southwesterly winds above the mountaintops. The resulting simulation produces wind directions within the modelled domain that are in much better agreement with the available measurements. However, despite the imposed atmospheric stability, downward transfer of horizontal momentum from aloft still appears to exceed that occurring in nature. It is recommended that (in future studies of this type regarding mountain wind climate) the input statistics processed from the NCEP/NCAR Reanalysis be modified by referencing the geostrophic winds to a level above the mountaintops. It is also suggested that converting to a height (z) coordinate system may reduce the erroneous downward momentum transfer found in the present terrain‐following grid. 相似文献
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2001年春季中国北方沙尘暴的环流动力结构分析 总被引：14，自引：15，他引：14
通过对2001年春季中国北方5次沙尘暴的高度场，涡度场，散度场和风场的分析，研究了沙尘暴强盛期的环流动力结构。结果表明，在5次沙尘暴强盛期有相似的环流动力结构特征。在沙尘暴强盛期的高度场上，蒙古国有深厚的低值系统，乌拉尔高压发展，其间的强气压梯度是沙尘暴的动力源；低值系统有正涡度中心支持，外围是负涡度区，其间有强涡度梯度带；低值中心伴随有低层辐合高层辐散的垂直结构，易于发生近地面大风和上升气流，有利于地面起沙上扬，形成沙尘暴，大风区与强涡度梯度带一致，强风带切变形成的涡度输送有利于加强低值系统，进而增强风场。 相似文献
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利用NCEP／NCAR再分析资料对2002年6月14—15日的暴雨过程进行了诊断分析,并利用中尺度模式MM5对暴雨过程进行云迹风资料的同化模拟。诊断分析表明：高空急流的动量下传、高低空急流的适宜配置所产生的动力场的耦合作用,为此次大范围暴雨的发生、发展提供了动力条件;此次暴雨过程充足稳定的水汽主要源自印度洋。对同化效果进行检验说明：两个时次的云迹风资料同化模拟与一个时次的云迹风资料同化模拟相比,前者更进一步地改善风场、温度场和高度场,使得物理量场和降水场的预报更加接近实况。 相似文献
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M. G. Sotillo A. W. Ratsimandresy J. C. Carretero A. Bentamy F. Valero F. González-Rouco 《Climate Dynamics》2005,25(2-3):219-236
A 44-year (1958–2001) high-resolution atmospheric hindcast for the whole Mediterranean Basin was performed within the EU-funded
Hindcast of Dynamic Processes of the Ocean and Coastal Areas of Europe (HIPOCAS) Project. The long-term hindcasted data set,
which comprises several atmospheric parameters at different levels, was produced by means of dynamical downscaling from the
NCEP/NCAR global reanalysis using the atmospheric limited area model REMO. The REMO hindcast has been exhaustively validated.
On that score, various hindcasted surface parameters, such as 10-m wind field, 2-m temperature and mean sea level pressure,
have been compared to satellite data (ERS-1/2 scatterometer) and in-situ measurements from offshore stations. In addition,
two ocean models (waves and sea level) have been forced with REMO hindcasted fields (mean sea level pressure and 10-m wind
field). The validation of these ocean runs, performed through comparisons of simulated waves and sea level with oceanographic
measurements, allows to evaluate "indirectly" the quality of the REMO hindcasted data used as atmospheric forcing. Once the
quality of the hindcasted data was verified, the efficiency of the regional enhancement performed through dynamical downscaling
on the NCEP global reanalysis was assessed. The regional improvement was evaluated through comparisons of REMO and NCEP performance
in reproducing observations. The important improvement obtained in the characterization of extreme wind events is particularly
remarkable. 相似文献
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Potential climate change impact on wind energy resources in northern Europe: analyses using a regional climate model 总被引：7，自引：0，他引：7
There is considerable interest in the potential impact of climate change on the feasibility and predictability of renewable
energy sources including wind energy. This paper presents dynamically downscaled near-surface wind fields and examines the
impact of climate change on near-surface flow and hence wind energy density across northern Europe. It is shown that: Simulated
wind fields from the Rossby Centre coupled Regional Climate Model (RCM) (RCAO) with boundary conditions derived from ECHAM4/OPYC3
AOGCM and the HadAM3H atmosphere-only GCM exhibit reasonable and realistic features as documented in reanalysis data products
during the control period (1961–1990). The near-surface wind speeds calculated for a climate change projection period of 2071–2100
are higher than during the control run for two IPCC emission scenarios (A2, B2) for simulations conducted using boundary conditions
from ECHAM4/OPYC3. The RCAO simulations conducted using boundary conditions from ECHAM4/OPYC3 indicate evidence for a small
increase in the annual wind energy resource over northern Europe between the control run and climate change projection period
and for more substantial increases in energy density during the winter season. However, the differences between the RCAO simulations
for the climate projection period and the control run are of similar magnitude to differences between the RCAO fields in the
control period and the NCEP/NCAR reanalysis data. Additionally, the simulations show a high degree of sensitivity to the boundary
conditions, and simulations conducted using boundary conditions from HadAM3H exhibit evidence of slight declines or no change
in wind speed and energy density between 1961–1990 and 2071–2100. Hence, the uncertainty of the projected wind changes is
relatively high. 相似文献
16.
副热带高压脊线移动的三维结构特征 总被引：1，自引：2，他引：1
文中定义了东西风交界面作为表征副热带高压脊线位置的动力学参量 ,并利用 NCEP/NCAR再分析月平均资料在三维空间中考察了东西风交界面的空间、时间变化特征。分析结果表明 :副热带高压位置移动以季节变化为主 ,季节变化由南北移动和斜率变化两类运动组成 ;副热带高压位置移动的年际变化和 ENSO事件关系密切 ;南半球副热带高压具有纬向对称的垂直结构 ,北半球副热带高压垂直结构较为复杂 ,尤其是西太平洋副热带高压表现出在全球副热带高压系统中的独特性。 相似文献
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利用2007年11月—2008年11月美国国家环境预报中心(NCEP)和国家大气中心(NCAR)的全球再分析资料与阜阳和安庆探空站的高空资料,对NCEP资料进行垂直的拉格朗日插值和水平的双线性插值后,对比分析了模式再分析与探空资料的一致性。结果表明:探空资料和NCEP资料中温度、相对湿度、u风和v风4种气象要素的绝对差值随地点、高度和季节变化较小,0.5～8 km基本稳定在一定的范围内:温度相差0.5～1.0℃,相对湿度相差5%～15%,u风和v风分别相差1～3 m/s和1～4 m/s。但值得注意的是近地面(0.5 km以下)二者差异相对较大。对比结果验证了利用模式探空资料来分析无实际探空资料地区上空气象参量变化特征的可行性。 相似文献
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利用NCEP/NCAR, NCEP/DOE和ERA40 3套再分析资料的逐日200 hPa纬向风数据,选取1961—1990年、1971—2000年和1981—2010年3种不同气候态,对比分析了3种气候态下热带大气季节内振荡 (ISO) 的基本气候特征及其在不同再分析资料中的异同。研究表明:1981—2010年气候态下,热带大气ISO冬春强、夏秋弱的年循环特征更加明显,东传短波能量增强,起始北传时间偏晚。NCEP/NCAR与NCEP/DOE资料所表征的热带大气ISO在空间分布、强度和能量传播方面的一致性较好。NCEP/NCAR资料反映的热带大气ISO强度在热带印度洋和热带西太平洋地区较ERA40资料偏弱,在赤道东太平洋地区较ERA40资料偏强;ERA40资料反映的热带大气ISO强度在12月—次年3月中旬较NCEP/NCAR资料偏强,而在3月中旬—11月偏弱;ERA40资料反映的热带大气ISO振荡位相较NCEP/NCAR资料超前10 d左右;NCEP/NCAR资料反映的东传谱能量弱于ERA40资料,西传能量强于ERA40资料;7月中旬,NCEP/NCAR资料反映的东亚地区大气ISO经向北传较ERA40资料偏晚。 相似文献
20.
A reexamination of the valley wind system in the Alpine Inn Valley with numerical simulations 总被引：2，自引：0，他引：2
G. Zängl 《Meteorology and Atmospheric Physics》2004,87(4):241-256
Summary This paper presents idealized numerical simulations of the valley wind circulation in the Alpine Inn Valley, which are compared with existing data and are used to improve our dynamical understanding of the valley wind. The simulations have been performed with the Penn State/NCAR mesoscale model MM5. They use a high-resolution realistic topography but idealized large-scale conditions without any synoptic forcing to focus on the thermally induced valley wind system. The comparison with the available observations shows that this simplified set-up is sufficient to reproduce the essential features of the valley wind.The results show that the tributaries of the Inn Valley have a considerable impact on the along-valley mass fluxes associated with the valley wind circulation. The upvalley mass flux is found to increase where tributaries enter the Inn Valley from the north, that is, from the direction where the Alpine foreland is located. On the other hand, the upvalley mass flux is reduced at the junctions with southern tributaries because part of the upvalley flow is deflected into these tributaries. For the downvalley flow, the situation is essentially reversed, but the influence of the valley geometry on the flow structure is larger than for the upvalley flow. The most important feature is a lateral valley contraction near the valley exit into the Alpine foreland. It reduces the downvalley mass flux at low levels, so that the wind maximum in the interior of the valley is shifted to a fairly large distance from the ground. North of the valley contraction, however, the downvalley flow strongly accelerates and forms a pronounced low-level jet. A dynamical analysis indicates that this acceleration can be interpreted as a transition from subcritical to supercritical hydraulic flow. Another interesting feature is that the low-level jet maintains its structure for several tenths of kilometres into the Alpine foreland. This appears to be related to the fact that the lateral wind shear on the flanks of the jet is associated with a strong dipole of potential vorticity (PV). Due to the conservation properties of the PV, the downstream advection of the PV dipole leads to the formation of a band-like feature that decays fairly slowly. 相似文献