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1.
Records of wind strength taken onboard Spanish and French ships during the 1750–1850 period have been digitized and examined
using content analysis techniques to derive the equivalent wind strength in terms of the current Beaufort scale, this conversion
being a key step in any attempt to compare ancient records with modern climatologies. During the analysis it was evident that
Spanish and French officers used a great number of different terms to describe the wind force. However, when the records are
analyzed and homogenized, a broadly common and essentially narrow vocabulary was identified, indicating that, at this period,
a great effort had been made to regulate the maritime language. Using contemporary dictionaries and navigation manuals, an
equivalence was established between the original wind force terms and the Beaufort scale. 相似文献
2.
R. García-Herrera G. P. Können D. A. Wheeler M. R. Prieto P. D. Jones F. B. Koek 《Climatic change》2005,73(1-2):1-12
We have compiled a meteorological database over the world's oceans by digitizing data from European ship logbooks of voyages
in the period 1750–1854. The observations are carefully reviewed and transformed into quantitative data. The chief contents
of the database are wind direction and wind force information, from a period without standardized scales. It is found that
the information content of these so-called non-instrumental data is much higher than previously believed. The 105-year CLIWOC
database extends existing meteorological world ocean databases like ICOADS back in time by a full century. 相似文献
3.
利用2013年1月—2014年12月山东近海的8个浮标站、海岛站和自动站资料与ASCAT近岸风速和风向进行对比,以分析ASCAT反演风场在山东沿海的适用性。研究发现：总体上看,ASCAT近岸风速与代表站实况风速正相关,ASCAT近岸风速在山东沿海误差较小,风向有明显的偏离。ASCAT近岸风在渤海、渤海海峡和黄海北部的适用性优于黄海中部。风力不同时,ASCAT近岸风速与实况偏差有明显差别,表现为当实况出现6级及以上的大风,ASCAT近岸风速小于实况;当实况出现6级以下的风,ASCAT近岸风速大于实况。就ASCAT风速偏差而言,6级以下的风速偏差小于6级及以上风。ASCAT近岸风向与实况偏差也有明显差别,当实况出现6级及以上的大风,ASCAT近岸风向与实况的偏离变小;当实况出现6级以下的风,ASCAT近岸风向与实况的偏离变大。因此,ASCAT近岸风速在山东沿海有较好的适用性,6级以下风更优;ASCAT近岸风向也有一定的适用性,6级及以上风向可用性比6级以下强。 相似文献
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5.
利用中国气象局《热带气旋年鉴》的热带气旋大风和降水资料集,确定了明显影响我国及华东和华南地区的热带气旋个例,并研制热带气旋年频数的预测方案,使得频数预测对防灾减灾更为实用。预测因子采用相关普查的方法,从1961—2000年前期的海表温度、海平面气压及200,500 hPa和850 hPa位势高度和风场中选出,所用的资料为NOAA ER SST和NCEP/NCAR再分析资料。在相关分析的基础上,构建因子时兼顾了因子的系统性的空间结构和时间的变化,并用主成分分析方法去除因子的多重共线性;在最优子集回归建模的基础上进一步对模型进行检验和优化。模型检验和2001—2008年回报试验说明各模型均对各自热带气旋频数 (TCF) 具有较好的预测能力。 相似文献
6.
Comparing the theoretical versions of the Beaufort scale, the T-Scale and the Fujita scale 总被引：1，自引：0，他引：1
G. Terence Meaden S. Kochev L. Kolendowicz A. Kosa-Kiss Izolda Marcinoniene Michalis Sioutas Heino Tooming John Tyrrell 《Atmospheric Research》2007,83(2-4):446-449
2005 is the bicentenary of the Beaufort Scale and its wind-speed codes: the marine version in 1805 and the land version later. In the 1920s when anemometers had come into general use, the Beaufort Scale was quantified by a formula based on experiment. In the early 1970s two tornado wind-speed scales were proposed: (1) an International T-Scale based on the Beaufort Scale; and (2) Fujita's damage scale developed for North America. The International Beaufort Scale and the T-Scale share a common root in having an integral theoretical relationship with an established scientific basis, whereas Fujita's Scale introduces criteria that make its intensities non-integral with Beaufort. Forces on the T-Scale, where T stands for Tornado force, span the range 0 to 10 which is highly useful world wide. The shorter range of Fujita's Scale (0 to 5) is acceptable for American use but less convenient elsewhere. To illustrate the simplicity of the decimal T-Scale, mean hurricane wind speed of Beaufort 12 is T2 on the T-Scale but F1.121 on the F-Scale; while a tornado wind speed of T9 (= B26) becomes F4.761. However, the three wind scales can be uni-fied by either making F-Scale numbers exactly half the magnitude of T-Scale numbers [i.e. F′half = T / 2 = (B / 4) − 4] or by doubling the numbers of this revised version to give integral equivalence with the T-Scale. The result is a decimal formula F′double = T = (B / 2) − 4 named the TF-Scale where TF stands for Tornado Force. This harmonious 10-digit scale has all the criteria needed for world-wide practical effectiveness. 相似文献
7.
Using measures of wind strength and direction taken onboard ships during the 1750–1850 (CLIWOC project) period, preliminary
reconstructions are attempted for the North Atlantic Oscillation (NAO) and the Southern Oscillation Index (SOI). The reconstructions
are based on regression equations developed using similar data from the ICOADS dataset. Although the regression relationships
developed over a calibration period (1881–1940) work almost as well over an independent verification period (1941–1997), application
to the earlier 1750–1850 period results in barely statistically significant correlation coefficients when compared with a
number of other NAO and SOI reconstructions from other proxy and long instrumental sources. A number of possibilities are
investigated to attempt to determine the cause, the most likely of which is that the number of observations available for
the CLIWOC period is just too low in some regions. As large numbers of ships' logbooks remain to be digitised, the regression
relationships will prove useful to focus effort in future digitisation endeavours. 相似文献
8.
Summary We consider the wind climatology of the Adriatic Sea derived from three different sources: an operational meteorological
model, a simplified wind model, and traditional ship reports. The simplified wind model is found to provide reliable results
in storm conditions, but it partly smoothes the fields when the meteorological pattern is not well defined and fairly uniform
at the basin scale.
The ship reports show a strong evident bias towards low values. This is partly interpreted as a tendency for ships to avoid
rough weather and not to report in these types of conditions. A second reason is a bias present in the transfer from the Beaufort
to the metric scale.
The best results are provided by the operational meteorological model, after its results have been corrected for a bias in
wind speed, associated with the resolution of the model with respect to the dimensions of the basin under study.
Received October 23, 1997 Revised August 10, 1998 相似文献
9.
山东即墨风电场风力资源分析 总被引：1，自引：2，他引：1
以即墨气象站风速风向为参考,利用其30年风速资料确定风电场代表年,根据铁塔气象观测资料分析即墨风电场的风力资源状况;依据“风能资源评价技术规定”对即墨风电场的风速风向进行了检验修正。分析了测风塔各高度风速日、年变化,风向频率年月变化。计算分析了测风塔不同高度平均风速、风功率密度、有效小时数等风能参数。计算了不同风电机型60~70 m轮毂高度年发电量及其随高度变化规律;估算了风电场年发电量。得出即墨风电场达到3级风场标准,具有开发价值。 相似文献
10.
The origin and space-time evolution of Beaufort-Chukchi Sea ice anomalies are studied using data and a recently developed
dynamic-thermodynamic sea-ice model. First, the relative importance of anomalies of river runoff, atmospheric temperature
and wind in creating anomalous sea-ice conditions in the Beaufort-Chukchi Sea is investigated. The results indicate that wind
anomalies are the dominant factor responsible for creating interannual variability in the Beaufort-Chukchi Sea ice cover.
Temperature anomalies appear to play a major role for longer time scale fluctuations, whereas the effects of runoff anomalies
are small. The sea-ice model is then used to track the position of a positive sea-ice anomaly as it is transported by the
Beaufort Gyre toward the Transpolar Drift Stream and then exported out of the Arctic Basin into the Greenland Sea via Fram
Strait. The model integration shows that sea-ice anomalies originating in the western Beaufort Sea can survive a few seasonal
cycles as they propogate through the Arctic Basin and can account for a notable amount of anomalous ice export into the Greenland
Sea. These anomalies, however, represent a small contribution to the fresh water budget in this area when compared with sea-ice
fluctuations generated by interannually varying local winds.
Received: 1 May 1997/Accepted: 22 October 1997 相似文献
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12.
Xingang Fan Jeremy R. Krieger Jing Zhang Xiangdong Zhang 《Boundary-Layer Meteorology》2013,148(1):207-226
To achieve a high-quality simulation of the surface wind field in the Chukchi/Beaufort Sea region, quick scatterometer (QuikSCAT) ocean surface winds were assimilated into the mesoscale Weather Research and Forecasting model by using its three-dimensional variational data assimilation system. The SeaWinds instrument on board the polar-orbiting QuikSCAT satellite is a specialized radar that measures ice-free ocean surface wind speed and direction at a horizontal resolution of 12.5 km. A total of eight assimilation case studies over two five-day periods, 1–5 October 2002 and 20–24 September 2004, were performed. The simulation results with and without the assimilation of QuikSCAT winds were then compared with QuikSCAT data available during the subsequent free-forecast period, coastal station observations, and North American Regional Reanalysis data. It was found that QuikSCAT winds are a potentially valuable resource for improving the simulation of ocean near-surface winds in the Chukchi/Beaufort Seas region. Specifically, the assimilation of QuikSCAT winds improved, (1) offshore surface winds as compared to unassimilated QuikSCAT winds, (2) sea-level pressure, planetary boundary-layer height, as well as surface heat fluxes, and (3) low-level wind fields and geopotential height. Verification against QuikSCAT data also demonstrated the temporal consistency and good quality of QuikSCAT observations. 相似文献
13.
利用逐小时风速观测资料以及台风年鉴资料,分析了2008~2014年登陆我国大陆地区的51次热带气旋（TC）的地面风场分布特征,包括TC登陆期间大陆地面风场演变和大风分布特征、海岛站和内陆站的风速差异以及海拔对风力造成的影响等。结果表明:6级及以上大风主要发生在距离TC中心300 km内、TC强度达到台风（TY）以上时,并主要位于TC移动方向的右侧,尤其是右前象限;华南区TC风场分布主要由在此区域登陆的TC（Ⅰ类）造成,较大风速区包括广东西南部沿海、雷州半岛附近和海南西部沿岸;华东区TC风场分布主要由在此区域登陆的TC（Ⅱ类）造成,杭州湾出海口以及浙闽沿海是较大风速区;6级及以上大风广泛分布在华南和华东沿海,6~7级地面大风高频站主要位于杭州湾附近,8级及以上地面大风高频站点在杭州湾和福建沿海分布比广东西南部更为密集;TC登陆前后均可能造成大风,大风出现时间与站点至TC中心的距离密切相关;同等强度TC在海岛站造成的风速比陆地站更大,对高海拔站点造成的风力大于低海拔站点。本文研究结论对于TC大陆地面风场的预报具有一定参考价值。 相似文献
14.
湖北浠水核电站周边地区龙卷风特征 总被引：1，自引：0，他引：1
根据湖北省浠水核电站周边300 km×300 km区域范围内1964—2007年龙卷风资料,对龙卷风的时间分布和灾害特征进行了分析。结果表明：龙卷风有明显的时间分布,一年之中主要集中在春、夏两季,秋、冬季无龙卷风发生,以7月最多;一天之中,午后至傍晚最多,集中在16：00—18：59之间,龙卷风平均持续时间27 min。近44年,21世纪头7年中龙卷风出现最为频繁。龙卷风出现时,蒲福风力等级一般在10级以上,集中出现在12级;富士达风力等级集中出现在F0、F1级,F2级以上出现的几率较小。龙卷风多以自西向东方向移动,影响宽度平均1.20 km,平均带长21.66 km。龙卷风灾害主要是风灾,往往伴有冰雹、暴雨、雷击,破坏力极强。 相似文献
15.
连云港沿海近地层湍流强度特征 总被引：1，自引：0，他引：1
在对连云港沿海15个各类气象观测站2000—2009年8级以上强风样本统计分析基础之上,利用6座沿海梯度测风塔2005—2007年测风资料,探讨了连云港沿海近地层风湍流强度的时空分布规律及特点,并重点对不同类型天气系统引起的强风湍流演变特征及其对风电场影响进行剖析。研究结果表明:①风湍流强度具有很强的季节性,冬季小、夏季大,随高度增加而减小;②海面动力粗糙度对海上强湍流变化的影响有别于无强风及下垫面是陆地时;③在热带气旋影响区域,同一时段内可能会出现风速和湍流强度瞬时骤变现象;④海上强湍流出现在30m以上高度,陆地出现在底层,这一现象在不同天气系统引起的强风湍流变化中都有发现;⑤风机轮毂高度处有2.1%～3.8%的湍流强度特征值超过目前风机最大抗湍流强度设计标准,建议华东中、北部沿海地区风机抗湍流强度参数调整为0.31～0.41。 相似文献
16.
北京"城市热岛"效应现状及特征 总被引：37，自引：16，他引：21
利用2002年北京自动气象站资料,对北京“城市热岛”效应现状进行了分析。为了与20世纪70年代的结果相比较,选择城区代表站为天安门广场站,城郊代表站为朝阳气象站站。与20世纪70年代相比,目前北京的“城市热岛”表现出一些新特点:1)利用城区与城郊日均温差表示的“城市热岛”强度的统计结果表明,现在北京的“城市热岛”效应在夏季最强,秋、冬季次之,春季最弱,2)除夏季“城市热岛”整天存在(午后的平均强度在2℃左右)以外,其他季节的午后,天安门广场地区经常出现“城市冷岛”现象。3)北京“城市热岛”消失的极限风速没有发生系统性变化,当风速>3级时,北京“城市热岛”基本上消失。作者还研究了北京“城市热岛”形成和消失的日变化特征,以及“城市热岛”强度对风速等气象要素变化的响应特征。值得指出的是,对强“城市热岛”的个案分析显示,冬季夜晚“城市热岛”强度经常表现出较大的波动性,与此相伴随,城郊地面风出现风向突变和风速的阵性现象。 相似文献
17.
基于CCMP风场的中国近海18个海区海面大风季节变化特征分析 总被引：3，自引：0，他引：3
利用1988-2010年CCMP(Cross Calibrated Multi-Platform)高时空分辨率10 m风场分析了我国近海海区的大风(6级以上)日数和大风风速的空间分布特征,并且按照中央气象台对近海海区的划分,分析了近海18个海区大风的季节变化特征.我国近海大风日数高值中心及大风风速高值中心都集中于巴士海峡、台湾海峡和南海东北部海域,在巴士海峡和南海东北部海域交界处最高可达140天以上,平均大风风速达到13m/s以上.从季节变化来看,大风日数和大风风速充分体现了东亚季风冬强夏弱的特点.冬半年,大风日数及风速高值中心一直位于东海东北部、台湾海峡、巴士海峡、南海东北部以及南海西南部海域,12月是一年之中大风日数和强度的峰值时期.从4月开始,南海西南部的高值中心消失,而以北海域的高值区的分布基本不变,这种情况一直持续到9月.近海18个海区的季节变化呈现出不同的区域差别,南海中部和南部的4个海域大风日数呈双峰型变化,冬季的12月至次年1月出现最高值,夏季西南季风时期的7-8月出现次高值.除琼州海峡外,包括南海北部海域的其余13个海区高值均在冬季12月至次年1月,低值出现在夏季6-7月. 相似文献
18.
选取1986-2005年抚顺地区3个测站地面自记风资料,探讨抚顺地区大风的时空分布规律。结果表明：近20a抚顺地区大风有多个高值年和低值年,平均7—8a为1个波段,2002年后大风日数明显减少。春季大风最多,冬季最少。根据环流形势特征,将大风分为两高夹低型、东高西低型、西高东低型和中小尺度型4种天气环流类型。建立了偏南大风、偏北大风和中小尺度型大风的预报指标和预报方法,为大风预报提供依据。选取2001-2005年40次大风观测数据进行预报效果检验．预报正确率为62％,检验效果较好。 相似文献
19.
The spatial variation and diurnal fluctuation of sea surface wind over the Qiongzhou Strait were described using verified datasets from automatic weather stations on board a ferry, buoys, and on the coast. Results are as follows: (1) On average, sea surface wind speed is 3–4 m/s larger over the Qiongzhou Strait than in the coastal area. Sea surface wind speeds of 8.0 m/s or above (on Beaufort scale five) in the coastal area are associated with speeds 5–6 m/s greater over the surface of the Qiongzhou Strait. (2) Gust coefficients for the Qiongzhou Strait decrease along with increasing wind speeds. When coastal wind speed is less than scale five, the average gust coefficient over the sea surface is between 1.4 and 1.5; when wind speed is equal to scale five or above, the average gust coefficient is about 1.35. (3) In autumn and winter, the diurnal differences of average wind speed and wind consistency over the strait are less than those in the coastal area; when wind speed is 10.8 m/s (scale six) or above, the diurnal difference of average wind speed decreases while wind consistency increases for both the strait and the coast. 相似文献
20.
选取1986－2006年抚顺地区3个测站地面自记风资料,探讨抚顺地区大风的时空分布规律。结果表明：近20 a抚顺地区大风有多个高值年和低值年,平均7－8年为1个波段,2002年后大风日数明显减少。春季大风最多,冬季最少。根据环流形势特征,将大风分为两高夹低型、东高西低型、西高东低型和中小尺度型4种天气环流类型。建立了偏南大风、偏北大风和中小尺度型大风的预报指标和预报方法,为大风预报提供依据。选取2001－2006年40次大风观测数据进行预报效果检验,预报正确率为62％,检验效果较好。 相似文献