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31.
Developing coastal adaptation to climate change in the New York City infrastructure-shed: process, approach, tools, and strategies 总被引:1,自引:0,他引:1
Cynthia Rosenzweig William D. Solecki Reginald Blake Malcolm Bowman Craig Faris Vivien Gornitz Radley Horton Klaus Jacob Alice LeBlanc Robin Leichenko Megan Linkin David Major Megan O��Grady Lesley Patrick Edna Sussman Gary Yohe Rae Zimmerman 《Climatic change》2011,106(1):93-127
While current rates of sea level rise and associated coastal flooding in the New York City region appear to be manageable by stakeholders responsible for communications, energy, transportation, and water infrastructure, projections for sea level rise and associated flooding in the future, especially those associated with rapid icemelt of the Greenland and West Antarctic Icesheets, may be outside the range of current capacity because extreme events might cause flooding beyond today??s planning and preparedness regimes. This paper describes the comprehensive process, approach, and tools for adaptation developed by the New York City Panel on Climate Change (NPCC) in conjunction with the region??s stakeholders who manage its critical infrastructure, much of which lies near the coast. It presents the adaptation framework and the sea-level rise and storm projections related to coastal risks developed through the stakeholder process. Climate change adaptation planning in New York City is characterized by a multi-jurisdictional stakeholder?Cscientist process, state-of-the-art scientific projections and mapping, and development of adaptation strategies based on a risk-management approach. 相似文献
32.
The effect exerted by the seabed morphology on the flow is commonly expressed by the hydraulic roughness, a fundamental parameter
in the understanding and simulation of hydro- and sediment dynamics in coastal areas. This study quantifies the hydraulic
roughness of large compound bedforms throughout a tidal cycle and investigates its relationship to averaged bedform dimensions.
Consecutive measurements with an acoustic Doppler current profiler and a multibeam echosounder were carried out in the Jade
tidal channel (North Sea, Germany) along large compound bedforms comprising ebb-oriented primary bedforms with superimposed
smaller secondary bedforms. Spatially averaged velocity profiles produced log-linear relationships which were used to calculate
roughness lengths. During the flood phase, the velocity profiles were best described by a single log-linear fit related to
the roughness created by the secondary bedforms. During the ebb phase, the velocity profiles were segmented, showing the existence
of at least two boundary layers: a lower one scaling with the superimposed secondary bedforms and an upper one scaling with
the ebb-oriented primary bedforms. The drag induced by the primary bedform during the ebb phase is suggested to be related
to flow expansion, separation, and recirculation on the downstream side of the bedform. Three existing formulas were tested
to predict roughness lengths from the local bedform dimensions. All three predicted the right order of magnitude for the average
roughness length but failed to predict its variation over the tidal cycle. 相似文献
33.
Alice Ghiselli Marzio Merazzi Andrea Strini Roberto Margutti Michele Mercuriali 《Central European Journal of Geosciences》2011,3(2):155-168
As karst systems are natural windows to the underground, speleology, combined with geological surveys, can be useful tools for helping understand the geological evolution of karst areas. In order to enhance the reconstruction of the structural setting in a gypsum karst area (Vena del Gesso, Romagna Apennines), a detailed analysis has been carried out on hypogeal data. Structural features (faults, fractures, tectonic foliations, bedding) have been mapped in the ”Grotta del Re Tiberio” cave, in the nearby gypsum quarry tunnels and open pit benches. Five fracture systems and six fault systems have been identified. The fault systems have been further analyzed through stereographic projections and geometric-kinematic evaluations in order to reconstruct the relative chronology of these structures. This analysis led to the detection of two deformation phases. The results permitted linking of the hypogeal data with the surface data both at a local and regional scale. At the local scale, fracture data collected in the underground have been compared with previous authors’ surface data coming from the quarry area. The two data sets show a very good correspondence, as every underground fracture system matches with one of the surface fracture system. Moreover, in the cave, a larger number of fractures belonging to each system could be mapped. At the regional scale, the two deformation phases detected can be integrated in the structural setting of the study area, thereby enhancing the tectonic interpretation of the area (e.g., structures belonging to a new deformation phase, not reported before, have been identified underground). The structural detailed hypogeal survey has, thus, provided very useful data, both by integrating the existing information and revealing new data not detected at the surface. In particular, some small structures (e.g., displacement markers and short fractures) are better preserved in the hypogeal environment than on the surface where the outcropping gypsum is more exposed to dissolution and recrystallization. The hypogeal geological survey, therefore, can be considered a powerful tool for integrating the surface and log data in order to enhance the reconstruction of the deformational history and to get a three-dimensional model of the bedrock in karst areas. 相似文献
34.
János Kovács Szabolcs Á. Fábián Gábor Varga Karoly Németh Corina Risso Francisco Nullo Gabor Kereszturi Titusz Bugya Szabolcs Á. Fábián Noémi L. Görcs István P. Kovács Bertalan Radvánszky Gabriella Barta Rudolf Musil Alice Ghiselli Marzio Merazzi Andrea Strini Roberto Margutti Michele Mercuriali Rauf Gardashov Daria Gushchina Boris Dewitte Martin Michálek Marián Putiš Christoph A. Hauzenberger Jindřich Šancer Martin Štrejbar Aneta Maleňáková George Migiros George D. Bathrellos Hariklia D. Skilodimou Theodoros Karamousalis 《Central European Journal of Geosciences》2011,3(2):229-229
35.
Janet M. Fischer Tara Reed-Andersen Jennifer L. Klug Alice G. Chalmers 《Estuaries and Coasts》2000,23(4):565-571
Geomorphology may be an important predictor of vegetation pattern in systems where suceptibility to disturbance is unevenly
distributed across the landscape. Salt marsh communities exhibit spatial pattern in vegetation at a variety of spatial scales.
In coastal Georgia, the low marsh is a virtual monoculture ofSpartina alterniflora interspersed with patches of species that are more typical of the high marsh. These localized disturbances are most likely
created by wrack mats, mats of dead vegetation which can compact and smother underlying vegetation creating bare patches for
colonization by high marsh species. We investigated the spatial pattern of disturbed patches along a 2 km section of Dean
Creek, a tidal creek at the southwestern end of Sapelo Island, Georgia, U.S. We used a discriminant model to explore the relationship
between tidal creek morphology (e.g., the presence of drainage channels and creek bends) and the spatial distribution of disturbed
patches. The model predicted vegetation pattern along the creek with relatively high accuracy (>70%). Areas where water movement
is slowed or multidirectional (e.g., along creek bends and near drainage channels) were most susceptible to disturbance. Our
findings suggest an important functional linkage between geomorphology and vegetation pattern in salt marsh communities. 相似文献
36.
Alice Vho Daniela Rubatto Benita Putlitz Anne‐Sophie Bouvier 《Geostandards and Geoanalytical Research》2020,44(3):459-471
Accurate ion microprobe analysis of oxygen isotope ratios in garnet requires appropriate reference materials to correct for instrumental mass fractionation that partly depends on the garnet chemistry (matrix effect). The matrix effect correlated with grossular, spessartine and andradite components was characterised for the Cameca IMS 1280HR at the SwissSIMS laboratory based on sixteen reference garnet samples. The correlations fit a second‐degree polynomial with maximum bias of ca. 4‰, 2‰ and 8‰, respectively. While the grossular composition range 0–25% is adequately covered by available reference materials, there is a paucity of them for intermediate compositions. We characterise three new garnet reference materials GRS2, GRS‐JH2 and CAP02 with a grossular content of 88.3 ± 1.2% (2s), 83.3 ± 0.8% and 32.5 ± 3.0%, respectively. Their micro scale homogeneity in oxygen isotope composition was evaluated by multiple SIMS sessions. The reference δ18O value was determined by CO2 laser fluorination (δ18OLF). GRS2 has δ18OLF = 8.01 ± 0.10‰ (2s) and repeatability within each SIMS session of 0.30–0.60‰ (2s), GRS‐JH2 has δ18OLF = 18.70 ± 0.08‰ and repeatability of 0.24–0.42‰ and CAP02 has δ18OLF = 4.64 ± 0.16‰ and repeatability of 0.40–0.46‰. 相似文献
37.
A review of paired catchment studies for determining changes in water yield resulting from alterations in vegetation 总被引:21,自引:0,他引:21
Alice E. Brown Lu Zhang Thomas A. McMahon Andrew W. Western Robert A. Vertessy 《Journal of Hydrology》2005,310(1-4):28-61
Paired catchment studies have been widely used as a means of determining the magnitude of water yield changes resulting from changes in vegetation. This review focuses on the use of paired catchment studies for determining the changes in water yield at various time scales resulting from permanent changes in vegetation. The review considers long term annual changes, adjustment time scales, the seasonal pattern of flows and changes in both annual and seasonal flow duration curves. The paired catchment studies reported in the literature have been divided into four broad categories: afforestation experiments, deforestation experiments, regrowth experiments and forest conversion experiments. Comparisons between paired catchment results and a mean annual water balance model are presented and show good agreement between the two methodologies. The results highlight the potential underestimation of water yield changes if regrowth experiments are used to predict the likely impact of permanent alterations to a catchment's vegetation. An analysis of annual water yield changes from afforestation, deforestation and regrowth experiments demonstrates that the time taken to reach a new equilibrium under permanent land use change varies considerably. Deforestation experiments reach a new equilibrium more quickly than afforestation experiments. The review of papers reporting seasonal changes in water yield highlights the proportionally larger impact on low flows. Flow duration curve comparison provides a potential means of gaining a greater understanding of the impact of vegetation on the distribution of daily flows. 相似文献
38.
The monsoon is a large‐scale feature of the tropical atmospheric circulation, affecting people and economies in the world's most densely populated regions. Future trends due to natural variability and human‐induced climate changes are uncertain. Palaeoclimate records can improve our understanding of monsoon dynamics and thereby reduce this uncertainty. Palaeoclimate records have revealed a dramatic decrease in the Asian summer monsoon since the early Holocene maximum 9 ka BP. Here we focus on the last 2 ka, where some records indicate an increasing trend in the summer monsoon. Analysing Globigerina bulloides upwelling records from the Arabian Sea, we find the weakest monsoon occurred 1500 a BP, with an increasing trend towards the present. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
39.
Natural Hazards - Over the past decade, the cost of disasters on lives and livelihoods has increased many folds. However, there are few tools available that can be used to measure the level of... 相似文献
40.
Poverty and Disasters in the United States: A Review of Recent Sociological Findings 总被引:2,自引:3,他引:2
This article synthesizes the literature on poverty and disasters in the United States and presents the results from a wide range of studies conducted over the past twenty years. The findings are organized into eight categories based on the stages of a disaster event. The review illustrates how people of different socioeconomic statuses perceive, prepare for, and respond to natural hazard risks, how low-income populations may be differentially impacted, both physically and psychologically, and how disaster effects vary by social class during the periods of emergency response, recovery, and reconstruction. The literature illustrates that the poor in the United States are more vulnerable to natural disasters due to such factors as place and type of residence, building construction, and social exclusion. The results have important implications for social equity and recommendations for future research and policy implementation are offered. 相似文献