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1.
The study analyses the numbers of days with strong winds in Krakow during the period 2000?C2007 using anemometric records and fire department data. Patterns are identified in the seasonal and annual variation of strong winds. Particular attention is devoted to extreme events. Based on measurements, the study finds that strong winds mostly occurred in winter. Fire department call-out data show that repair of damage caused by strong winds and gusts of wind was needed equally as frequently in summertime. Strong winds accompanying summer storms are often of a local nature and are not always recorded by weather stations. Wind damage was mapped using requests for fire department assistance. 相似文献
2.
Torben C. Rick 《Geoarchaeology》2002,17(8):811-833
Geomorphological evidence and historical wind records indicate that eolian processes have heavily influenced San Miguel Island environments for much of the Late Quaternary. The island is almost constantly bombarded by prevailing northwesterly winds, with peak velocities exceeding 75 km/h and wind gusts reaching over 100 km/h. These strong winds played an important role in the location, formation, and preservation of the island's more than 600 archaeological sites. Excavation and surface collection at a stratified Middle and Late Holocene archaeological site on the island's north coast suggest that wind related disturbances result in significant displacement of light fish bones, produce concentrations of shellfish and heavy mammal bones, and cause significant abrasion, etching, and polishing of bones, shells, and artifacts. These data illustrate that wind not only alters surface materials but can significantly disturb subsurface deposits to a depth of at least 20 cm. Working in concert with a variety of taphonomic processes, wind can play a fundamental role in the preservation of archaeological sites and careful scrutiny during excavation and laboratory analysis is required to delineate its effects. © 2002 Wiley Periodicals, Inc. 相似文献
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Fabio Manca Giuseppe Capelli Francesco La Vigna Roberto Mazza Annalisa Pascarella 《Environmental Earth Sciences》2014,72(4):1083-1095
The wind effect on river water quality was illustrated by means of thermohaline measurements carried out in the Tiber River in May 2012. The survey was carried out using a boat, in stations located in the two Tiber branches: Fiumara Grande and Traiano Canal. Thermohaline variables (salinity and temperature) were used to describe the water-type patterns and to define the salt-wedge position. Although the river flow rate was rather high, saltwater intrusion happened. Wind data suggested that the more probable cause of salt-wedge intrusion was the wind action. Especially wind speeds higher than 4 m/s are able to dominate the sea current at surface layers, determining an increase in the sea level. Therefore, westerly winds determined a seawater inflow in the river mouths. 相似文献
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P. Ernest Raj S. K. Saha S. M. Sonbawne S. M. Deshpande P. C. S. Devara Y. Jaya Rao K. K. Dani G. Pandithurai 《Journal of Earth System Science》2008,117(1):293-302
Lidar observations of aerosol vertical distributions in the lower troposphere along with observations of horizontal and vertical winds from collocated UHF radar (Wind Profiler) over a tropical Indian station, Pune during the pre-monsoon season (March–May) of 2006 as part of an ISRO-GBP national campaign (ICARB) have been examined. Lidar vertical profiles showed high aerosol concentrations in the surface layers and a subsequent gradual decrease with height. Results showed the presence of an elevated stratified aerosol layer around 2000–3500m height which persisted throughout the months of March and April. Observed strong vertical gradients in both horizontal and vertical winds in the lower troposphere seem to be a possible cause for the formation of elevated aerosol layers. Further, high daytime temperatures accompanied by dry conditions at the surface help to enhance the aerosol loading in the lower layers over this location. 相似文献
6.
Deep crustal reflection data that are critical for the interpretation of Laramide structure have been obtained by the Consortium for Continental Reflection Profiling (COCORP). The Laramide orogeny, which occurred from the late Cretaceous to early Eocene, is characterized in Wyoming by large uplifts of Precambrian basement, commonly flanked by reverse faults. The attitude of these faults at depth has been a major tectonic problem and is very important for deciding whether horizontal or vertical crustal movements were primarily responsible for the basement uplifts. COCORP has run 158 km of deep seismic reflection profiles (recording to 20-sec two-way travel time) across the southeastern end of the Wind River Mountains, the largest of these Laramide uplifts. Reflections from the thrust fault flanking the Wind River uplift can be clearly traced on the profiles to at least 24-km depth and possibly as deep as about 36 km with a fairly uniform apparent dip of 30°–35°. Other reflection events subparallel to the main Wind River thrust are present in the seismic profiles and may represent other faults. There is at least 21 km of crustal shortening along the thrust. There is no evidence in the reflection profiles for large-scale folding of the basement; the Wind River Mountains were formed predominantly by thrust movements. Gravity anomalies in the Wind River Mountains can be modeled by a thrust that displaces dense material in the lower crust. If the thrust ever cut the Moho, the effect is not observed in the gravity today. A proposed model for the presence of uplifted basement in Wyoming invokes a shallowly dipping, subducted Farallon plate beneath the North American continent; drag between the two plates localized compressional stresses in an area over 800 km into the North American plate causing large thrusts to develop. The earth's crust seems to have fractured as a fairly rigid plate 相似文献
7.
Wind streaks with two-dimensional plane shapes are a collective term for a variety of aeolian features that display distinctive albedo surface patterns and they do not have three-dimensional shape. Wind streaks are widely distributed on Mars， and are good proxy indicators of the surface wind regime， and even of global circulation patterns on Mars. However， the study on wind streaks has been largely ignored for a long time. Based on published studies， this paper summarized the types， morphology and formation mechanism of wind streaks. According to the relationship between albedo and obstacles， wind streaks can be divided into six basic types： bright wind streaks， dark wind streaks， mixed-tone wind streaks， splotches and related wind streaks， dune shadow wind streaks and frost wind streaks， of which the bright and dark streaks are the most common and representative， for they are the most abundant types of variable features on Mars. Wind streaks are primarily distributed in the latitudinal zone between 60°S and 60°N with little difference among different types， and they have many shapes such as tapered， fan， oval and parallel shapes due to the diverse obstacles. Considering the relationship between sediment characteristics and aeolian erosion and deposition， bright wind streaks are generally depositional with a consensus and dark streaks are erosional with a controversy. In the absence of Martian meteorological observation data， the retrieval of surface wind regime based on the orientation of wind streaks has good reliability， which helps to understand the modifications of Martian surfaces by wind in the geological context. 相似文献
8.
M. L. Eskijian 《Natural Hazards》2006,39(2):343-351
For the past 12 years, the California State Lands Commission has been involved in the operational monitoring, structural inspection
and requalification of 45 marine oil terminals along California’s coast, which have an average age of about 50 years and plans
to keep these structures in service for another 20–40 years. Having seen the port and harbor damage from the 1995 Kobe and
1999 Izmit earthquakes, the potential for a major disruption in petroleum product production is real. Losing the daily gasoline
production for a period of weeks or months as a result of a moderate earthquake or tsunami could significantly affect the
economic well being of California and much of the western United States. In addition, a major oil spill resulting from such
an event could cause the closure of a major port for days or even weeks. Such a closure would further affect the economy of
California and the United States. Most of these facilities were designed to primitive seismic standards and for vessels much
smaller than those currently moored. Many of these structures have never had a comprehensive underwater inspection. Wind and
current forces on large tank ships can cause mooring lines to break or cause serious structural damage to supporting structures.
In California, non-regulatory progress has been made in the following areas: (i) underwater and above water inspections or
audits; (ii) mooring analyses and structural/environmental monitoring in high velocity current areas; (iii) seismic analyses
and structural rehabilitation with updated seismic hazard data; and (iv) accelerometers on marine structures. In addition,
standards have been developed and are proposed to be regulatory by early 2004. The new standards include most of the items
listed above, but also extend into many other areas. Along with the proposed regulations come many issues that raise economic
and political questions. These issues are not unique to marine oil terminals and are applicable to other pier and wharf structures
in harbors. 相似文献
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Outcrops of the Early Jurassic Navajo Sandstone in southern Utah and northern Arizona, south-western USA are being actively eroded by sand-laden, south-westerly winds. Small-scale stepped topography with risers facing into the wind develops even on steep canyon walls when wind-swept grains strike the rock at a low angle. Photosynthetic, endolithic microbes directly underlie most outcrop surfaces; the crusts formed by these organisms are essential to formation of the small-scale steps. Wind erosion of highlands also forms troughs and pits that are tens of metres across. The pits have deeply scalloped, overhanging walls, and contain central domes surrounded by 'moats' filled with dune sand. Wind erosion of aeolian sandstone is favoured by a positive feedback mechanism in which grains that are liberated from outcrops by impacting particles become a fresh supply of pre-sorted abrasive particles for further attack. 相似文献
11.
风动力场对沉积体系的作用 总被引：2，自引：1，他引：1
风作为大气流场活动的表现形式,是一种重要的地质营力,风场对沉积体系的展布有着重要的控制作用。风不但本身具有侵蚀、搬运和沉积的能力,形成风成沉积,它还可以向水体传输能量和动量,产生波浪和风生水流,侵蚀基岩、改造已有的沉积物,形成独特的沉积体系。以风场对沉积物的直接作用和间接作用为依据,将风场作用下的碎屑岩及碳酸盐岩沉积体系进行了分类:背风体系、迎风体系及侧风体系。风场概念的引入,为解释沉积体系（包括油气储集体）形成及预测其分布提供了新的视角,也完善了古气候学中古风场的恢复。 相似文献
12.
为探究季节性冰封浅湖热力学特征,于2010年10月至2013年7月对高原腹地一典型热融湖塘冰层生消、水/冰温及气象条件开展原位观测,分析了水温分布时间变化、温跃层以及冰生消对水温结构的影响。结果发现:冰面升华显著,贯穿整个冰期;水温日变化、季节变化和垂直结构受气温、大气辐射、风速、冰生消和湖底沉积层热贡献影响显著;在"无冰期-结冰前-冰生长期-冰融化期-融化后-无冰期"年循环过程中水温垂直结构分别呈现出"分层-翻转-逆温分层-逆温与正温共存-翻转-分层"的循环过程。分层期水温结构仅由上部混合层和温跃层构成,且偶因强风搅动而全湖翻转混合。可见,相比大中型湖泊,季节性冰封浅湖热力学结构差异显著。 相似文献
13.
HEINZ LANGE 《Sedimentology》1982,29(3):427-431
Chlorite in the Atlantic sediments is predominantly derived from the Atlas Mountains, kaolinite originates in the southern Sahara and Sahel zone. These minerals may be used to reconstruct the tracks of two superimposed wind systems (Trade Winds and Harmattan Wind). A modified method for determining relative abundances of chlorite and kaolinite is presented. 相似文献
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S. M. N. Shojaee O. Uzol Ö. Kurç 《International Journal of Environmental Science and Technology》2014,11(1):59-68
This paper presents the design, computational analysis and experimental study of passive device configurations which utilized in the Ankara Wind Tunnel to simulate the atmospheric boundary layer within the test section. The study here is part of a joint project between the Aerospace and Civil Engineering Departments at Middle East Technical University, which involves testing of high-rise building models in the Ankara Wind Tunnel. The design consists of spires and rows of cubical surface roughness elements at the inlet. The preliminary computational analysis shows that the current design may provide the desired boundary layer thickness at about 4.0 m downstream of the test section inlet, which leaves enough room for the building models to be placed in the test section. This study also helps obtaining a preliminary understanding of the boundary layer development and reducing the tunnel operation time and cost during the actual experimentation phase. At the end, experimental results show acceptable results of this study. 相似文献
15.
Book reviewed in this article:
Seppälä, M. 2004: Wind as a Geomorphic Agent in Cold Climates
van der Meer, J. J. M. (ed.) 2004: Spitsbergen Push Moraines. Developments in Quaternary Science 4 相似文献
Seppälä, M. 2004: Wind as a Geomorphic Agent in Cold Climates
van der Meer, J. J. M. (ed.) 2004: Spitsbergen Push Moraines. Developments in Quaternary Science 4 相似文献
16.
Thomas W. Schmidlin 《Natural Hazards》2011,58(1):235-249
Hurricane Ike struck Galveston, Texas, on 13 September 2008, and transitioned to an extra-tropical cyclone on 14 September
as it moved across Ohio with wind gusts of 28–35 ms−1. This was the second most disruptive statewide windstorm in Ohio since 1913, and it caused the largest electrical failure
in Ohio history, with 2 million customers without power. Private insured losses of $1.1 billion were the largest for a natural
disaster in Ohio since 1974. There were seven deaths caused by the storm and 603 injuries. The American Red Cross opened 25
shelters and 86 feeding stations. Hospitals and public water supply systems used backup generators to maintain operations.
Public health consequences of the storm were minimized by good preplanning and preparedness at the local level, by moderate
temperatures during the massive power failure, and the response of governments, the American Red Cross, charitable and service
organizations, and private citizens. 相似文献
17.
Myslenkov S. A. Platonov V. S. Silvestrova K. P. Dobrolyubov S. A. 《Doklady Earth Sciences》2021,498(2):502-508
Doklady Earth Sciences - Wind wave modeling (WAVEWATCH III model) is used to analyze the storm activity in the Kara Sea for the period from 1979 to 2019. The NCEP/CFSR/CFSv2 reanalysis data used as... 相似文献
18.
前陆盆地的三维挠曲数值模拟是预测盆地三维格架和关键构造要素分布的强有力工具, 如在预测前隆分布方面(低隆起幅度、大范围分布的前隆很难从地下资料中识别)。为了解释详细地层对比中发现的前隆迁移,对怀俄明西南晚白垩世前陆盆地做了三维挠曲数值模拟。模拟过程中采用弹性地壳模型,并以详细的年代地层资料作为基本的输入数据。挠曲负载的估计来源于公开发表的怀俄明逆冲带的横剖面资料和风河逆冲带的缩短速率。模拟结果表明,由于逆冲负载的分布,前隆只局限分布在盆地的南部。随负载的迁移,前隆随时间向东南方向迁移。由于怀俄明逆冲带和风河逆冲带的相互作用,弹性地壳形成三维“前缘穹隆”而不是二维“前缘隆起”。三维挠曲模拟是理解怀俄明西南晚白垩世前隆迁移的关键。 相似文献
19.
For consideration of structural design of buildings and infrastructure in Australia, this paper presents hazard modelling and mapping of extreme wind gusts under the current climate and likely future climate change. Statistical and probabilistic approaches are applied to analyse the daily extreme wind gust data recorded between 1939 and 2007 at 545 anemometer stations around Australia. The estimated hazards are compared with the regional design wind speeds specified by the structural design standard, AS/NZS 1170.2:2011. Our results indicate that, under the current climate, structures in the areas on the west of and around Brisbane, Queensland and Newcastle, New South Wales, may be under higher gust hazard than they are designed for. Sensitivity study shows that these areas are also sensitive to the projected synoptic wind intensity changes. When subjected to ±20 % intensity change and ±50 % occurrence frequency change of tropical cyclones, the northwest coast of Western Australia, the northern part of Northern Territory, and the northeast coast between Cairns and Townsville, Queensland, will experience around ±10 m/s changes in extreme wind gust speeds of 500-year return period. 相似文献
20.
Robert D. Hall 《Quaternary Research》1999,51(3):248
Soil chronofunctions are often quasilinear, but those relationships may be only gross, fortuitous generalizations that ignore changes in soils resulting from climatic and other cyclic external influences that govern soil formation or soil degradation. In the Rocky Mountains, soil development has been extensively used to estimate the age of sediments, but the number of soils is usually few, and large ranges in values for soil data may be dismissed as “normal variation.” In a detailed study of soils in the Wind River Range and Wind River Basin, characteristics of near-surface horizons do not follow age trends. However, the underlying carbonate-bearing horizons do have age-related characteristics. This “soil paradox” may be related to glacial–interglacial cycles in which (1) wind erodes near-surface horizons and then provides new parent material and (2) cryoturbation disrupts carbonate horizons, remobilizing carbonate and changing carbonate morphology but with only minimal loss of carbonate from the soil. 相似文献