Influence of road network and population demand assumptions in evacuation modeling for distant tsunamis     

Kevin D. Henry  Nathan J. Wood  Tim G. Frazier 《Natural Hazards》2017,85(3):1665-1687

Tsunami evacuation planning in coastal communities is typically focused on local events where at-risk individuals must move on foot in a matter of minutes to safety. Less attention has been placed on distant tsunamis, where evacuations unfold over several hours, are often dominated by vehicle use and are managed by public safety officials. Traditional traffic simulation models focus on estimating clearance times but often overlook the influence of varying population demand, alternative modes, background traffic, shadow evacuation, and traffic management alternatives. These factors are especially important for island communities with limited egress options to safety. We use the coastal community of Balboa Island, California (USA), as a case study to explore the range of potential clearance times prior to wave arrival for a distant tsunami scenario. We use a first-in–first-out queuing simulation environment to estimate variations in clearance times, given varying assumptions of the evacuating population (demand) and the road network over which they evacuate (supply). Results suggest clearance times are less than wave arrival times for a distant tsunami, except when we assume maximum vehicle usage for residents, employees, and tourists for a weekend scenario. A two-lane bridge to the mainland was the primary traffic bottleneck, thereby minimizing the effect of departure times, shadow evacuations, background traffic, boat-based evacuations, and traffic light timing on overall community clearance time. Reducing vehicular demand generally reduced clearance time, whereas improvements to road capacity had mixed results. Finally, failure to recognize non-residential employee and tourist populations in the vehicle demand substantially underestimated clearance time.  相似文献   

Measured and modelled contributions to UV exposures by the albedo of surfaces in an urban environment     

A. V. Parisi  J. Sabburg  M. G. Kimlin  N. Downs 《Theoretical and Applied Climatology》2003,76(3-4):181-188

Summary The increases in the erythemal UV exposures to horizontal planes and to inclined planes over three surfaces that are found in an urban environment (water, concrete and sand) due to the albedo of these surfaces have been estimated. For the cloud free case, the additional daily estimated UV exposures to a horizontal plane have a maximum value of 222 (Jm^–2)_ER, where the index after the unit is there to indicate that it refers to a biologically effective exposure. In comparison, the daily erythemal UV exposures over a year to a horizontal plane ranged from 425 to 8,321 (Jm^–2)_ER. For a vertical receiving plane that is rotating about a vertical axis, the additional erythemal daily UV exposures for the sub-tropical latitude location of this research for the ranges of solar azimuth angles encountered over the days in each season ranged from 16 to 311 (Jm^–2)_ER, 29 to 566 (Jm^–2)_ER and 46 to 905 (Jm^–2)_ER for water, concrete and sand respectively. The estimated error is ±20% and the calculations are based on clear-sky conditions. The additional erythemal UV averaged over each of the seasons was higher for the receiving plane inclined at 45° below the horizontal plane. In a similar fashion, the vertical surface has the higher additional erythemal UV exposures compared to the surfaces inclined at an angle above the horizontal.  相似文献   

Combining compositional zoning and foliation intersection axes (FIAs) in garnet to quantitatively determine early P-T-t paths in multiply deformed and metamorphosed schists: north central Massachusetts,USA     

Hyeong?Soo?KimEmail author  Tim?H.?Bell 《Contributions to Mineralogy and Petrology》2005,149(2):141-163

Quantitative compositional and microstructural analysis of garnet porphyroblasts in kyanite–staurolite–garnet grade rocks from the northeastern flank of the Pelham dome, north central Massachusetts, distinguishes the effects of Acadian deformation and metamorphism from extensive overprinting Alleghanian shearing. The P–T conditions and the metamorphic path during the Acadian were determined using samples preserving well defined stages in a lengthy tectonic history revealed by a succession of five foliation intersection axis trends preserved within porphyroblasts (FIAs). This Acadian succession extends at least 120 km to the north into rocks where no evidence has been found of an Alleghanian overprint. For each sample where garnet first nucleated during one of these stages in the tectonic history, the PT of core growth was determined by plotting the intersection of the Mn, Fe and Ca isopleths calculated for the core composition on a P–T pseudosection for that sample using THERMOCALC. Combining the PT data from all these samples indicates that the temperature and pressure increased throughout Acadian orogenesis, causing episodic garnet growth. During the Alleghanian, locally intense shearing, especially against the margin of the Pelham dome, formed the dominant schistosity, which truncated all foliations defined by inclusion trails in porphyroblasts and obliterated all remains of Acadian deformation and metamorphism in the rock matrix. Shearing was accompanied by near complete homogenization of the compositional zoning in garnet porphyroblasts and an associated apparent increase in the temperature of the matrix to 700°C in those rocks lying directly adjacent to the Pelham dome, and resulted from the rocks of the Northfield syncline being thrust a large distance southwards over the gneisses in the dome.  相似文献   

STARE Results on a Single Field: Tens of New Pulsating Stars     

Roi Alonso  Juan Antonio Belmonte  Tim Brown 《Astrophysics and Space Science》2003,284(1):13-16

We present preliminary results on variable stars of aSTARE's three month observational run centered at the Cygnus constellation.A total amount of aprox. 14000 stars with 9^2 FOV, have been analyzed to obtainlightcurves for each of these stars.The data spans for 90 nights.In this single field, we detect more that 40 stars withpulsation modes between 5 and 40 c/d, the vast mayoritypreviously unknown to be variables.  相似文献   

Membership, binarity and accretion among very low-mass stars and brown dwarfs of the σ Orionis cluster     

M. J. Kenyon  R. D. Jeffries  Tim Naylor  J. M. Oliveira  P. F. L. Maxted 《Monthly notices of the Royal Astronomical Society》2005,356(1):89-106

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THE DECLINE OF PARTY VOTING: A GEOGRAPHICAL ANALYSIS OF THE 1978 MASSACHUSETTS ELECTION     

Bruce Downing  Tim Hudson  Peter Taylor  Peter Bland  Nancy Villanueva 《The Professional geographer》1980,32(4):454-461

A factor analysis of the 1978 Massachusetts election is undertaken to investigate whether the alleged decline of political parties in the United States can be distinguished at the state scale. Four factors are identified, two of which relate to the voting patterns of state-wide candidates. The main factor is easily seen to represent a “party voting”pattern and the fourth factor suggests a nonparty pattern of support associated with the Democratic candidate for governor, Edward King. It is suggested that this separation of the voting pattern for Democratic candidates may possibly reflect party decomposition in Massachusetts.  相似文献   

The global 2000 report to the President: A report prepared by the Council on Environmental Quality and the Department of State. London: Penguin, 1982. 751 pp. £7.95 paperback; £14.95 hardback (Allen Lane)     

Tim O&#x;Riordan 《Applied geography (Sevenoaks, England)》1982,2(4):315-317

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Multiple Foliations Defined by Different Sillimanite Crystal Habits, Partial Melting and the Late Metamorphic Development of the Cannington Ag-Pb-Zn Deposit, Northeast Australia     

Hyeong Soo Kim  Tim H. Bell   《Gondwana Research》2005,8(4):493-509

A succession of foliations defined by different sillimanite-bearing structural fabrics suggests that the macroscopic, isoclinal synform that dominates the geometry of the Cannington Ag-Pb-Zn deposit, northwest Queensland, Australia formed during D₂. The five foliations in this succession, S₁ to S₅, are defined by aligned sillimanite with habits ranging from individual crystals in S₁ through S₄ to clusters of fibrolite in S₅ in both the matrix and as inclusion trails within garnet and gahnite (Zn-rich spinel) porphyroblasts. S₁, S₃ and S₅ formed as sub-horizontal foliations, whereas S_1a, S₂ and S₄ formed sub-vertically. Foliation intersection/inflexion axes (FIAs) within garnet and gahnite porphyroblasts preserve a succession of trends that shifts from W-E to N-S. This succession indicates that this region experienced N-S followed by W-E bulk crustal shortening. N-S shortening occurred during D₁and D_1a, and W-E shortening occurred from D₂ to D₅. Prismatic and rhombic sillimanite produced during D₁-D₄ accompanied prograde metamorphism to ca. 634 62°C and 4.8 1.3 kbar. The coexistence of fibrous, prismatic and rhombic sillimanite resulted from post peak metamorphic reactivation of the early foliations during D₅. The synformal D₂ fold was intensified during D₄ by W-E bulk shortening. Local partial melting occurred after D₁ in the appropriate bulk rock compositions, based on calculation of P-T pseudosections in the chemical systems KFMASH, KFMASHTO, NCKFMASH and MnNCKFMASH. Zn mineralization related to gahnite growth occurred during D₃ through D₄, and was redistributed by partial melting into structural and rheological sites during D₄ and D₅shearing.  相似文献   

The major-ion composition of Permian seawater   总被引：1，自引：0，他引：1  

Tim K. Lowenstein  Michael N. Timofeeff  Juske Horita 《Geochimica et cosmochimica acta》2005,69(7):1701-1719

The major-ion (Mg²⁺, Ca²⁺, Na⁺, K⁺, SO₄²⁻, and Cl⁻) composition of Permian seawater was determined from chemical analyses of fluid inclusions in marine halites. New data from the Upper Permian San Andres Formation of Texas (274-272 Ma) and Salado Formation of New Mexico (251 Ma), analyzed by the environmental scanning electron microscopy (ESEM) X-ray energy-dispersive spectrometry (EDS) method, along with published chemical compositions of fluid inclusions in Permian marine halites from North America (two formations of different ages) and the Central and Eastern European basins (eight formations of four different ages) show that Permian seawater shares chemical characteristics with modern seawater, including SO₄²⁻ > Ca²⁺ at the point of gypsum precipitation, evolution into Mg²⁺-Na⁺-K⁺-SO₄²⁻-Cl⁻ brines, and Mg²⁺/K⁺ ratios ∼5. Permian seawater, however, is slightly depleted in SO₄²⁻ and enriched in Ca²⁺, although modeling results do not rule out Ca²⁺ concentrations close to those in present-day seawater. Na⁺ and Mg²⁺ in Permian seawater are close to (slightly below) their concentrations in modern seawater. Permian and modern seawater are both classified as aragonite seas, with Mg²⁺/Ca²⁺ ratios >2, conditions favorable for precipitation of aragonite and magnesian calcite as ooids and cements.The chemistry of Permian seawater was modeled using the chemical composition of brine inclusions for three periods: Lower Permian Asselian-Sakmarian (296-283 Ma), Lower Permian Artinskian-Kungurian (283-274 Ma), and Upper Permian Tatarian (258-251 Ma). Parallel changes in the chemistry of brine inclusions from equivalent age evaporites in North America, Central Europe, and Eastern Europe show that seawater underwent secular variations in chemistry over the 50 million years of the Permian. Modeled SO₄²⁻ concentrations are 20 mmol per kg H₂O (mmolal) and 19 mmolal in the Asselian-Sakmarian and Artinskian-Kungurian, with higher concentrations in the Upper Permian Tatarian (23 mmolal). Modeled Ca²⁺ is at or above its concentration in modern seawater throughout the Permian. Mg²⁺ is close to (slightly below) its concentration in modern seawater (55 mmolal) in the Asselian-Sakmarian (52 mmolal), and Tatarian (52 mmolal), but slightly higher than modern seawater in the Artinskian-Kungurian (60 mmolal). Mg²⁺/Ca²⁺ ratios are 3.5 (total range = 2.7 to 5.5) in the Lower Permian and rose slightly to 3.7 (total range = 3.1 to 5.8) in the Upper Permian, primarily due to decreases in Ca²⁺. These results are consistent with models that predict oscillations in the major-ion composition of Phanerozoic seawater on the basis of changes in the midocean ridge/river water flux ratio driven by changes in the rate of midocean ridge crust production.The Permian was characterized by low sea levels, icehouse conditions, and southern hemisphere glaciation. Such conditions, analogous to the present ice age, and the similarities between Permian seawater and modern seawater, all suggest that general Phanerozoic supercycles, driven by mantle convection and global volcanicity, also control the major-ion chemistry of seawater.  相似文献   

'This is like my comfort zone': Senses of place and belonging within Oruāmo/Beachhaven, New Zealand     

Tim McCreanor  Liane Penney  Victoria Jensen  Karen Witten  Robin Kearns  Helen Moewaka Barnes 《New Zealand geographer》2006,62(3):196-207

Abstract:  This paper examines the culturally specific experiences of belonging within Oruāmo/Beachhaven, a suburb in North Shore City. In-depth interviews with 32 caregivers of young children expose the fact that the ethnic groups represented – Māori, Samoan and Pākehā– vary in their uses and understandings of, as well as feelings for, residential neighbourhood. Examination of the themes of natural environment, social relations, continuity of residence, facilities, organisations and place transformation reveal that, while representatives of all groups had views on these matters, there was a variable degree of engagement with and priority afforded to these concerns.  相似文献