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41.
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
42.
Chelsea L. Pederson James S. Klaus Peter K. Swart Donald F. Mcneill 《Sedimentology》2019,66(6):1989-2010
Microbial carbonate mud in the modern (<4 kyr) palustrine environment of the Florida Everglades is surprisingly susceptible to early diagenetic alteration. The low‐Mg calcite crystals show an open, trellis‐like crystal structure that yields a high surface area to volume ratio. This textural complexity, likely to be a result of organic influence, leads to abundant reaction sites vulnerable to both dissolution and subsequent precipitation. Rapid degradation of organics is attributed to both aerobic and anaerobic metabolisms. Geochemical signatures suggest increased denitrification within the freshwater environment and increased sulphate reduction at the (slightly) brackish mangrove transition zone. A transition from a freshwater to brackish depositional environment is likely to follow the Holocene sea‐level transgression. The textural complexity in these microbial carbonates causes an unexpectedly low preservation potential of original textural and geochemical signatures, even in low‐Mg calcite. Given the potential for early diagenesis of palustrine and perhaps other microbial carbonates, they should be used cautiously as archives for palaeoenvironmental proxies. 相似文献
43.
Udo Zimmermann Heinrich Bahlburg Klaus Mezger Jasper Berndt Suzanne Mahlburg Kay 《International Journal of Earth Sciences》2014,103(4):1023-1036
Ultramafic rocks and gabbros are exposed in the southern Puna (NW Argentina) in tectonic association with continental arc-related Ordovician (volcano) sedimentary successions and granitoids. The origin of this mafic rock suite has been debated for three decades as either representing an Ordovician terrane suture, primitive Ordovician arc-related rocks or relics of the pre-Ordovician basement in tectonic contact with the Ordovician retro-arc basin successions. We present the first U–Pb ages of primary and inherited zircon from gabbros of this mafic–ultramafic assemblage. LA-ICP-MS analyses on cores and rims of these zircon grains yielded a concordia age of 543.4 ± 7.2 Ma for the gabbroic rocks. Other analysed zircons have Mesoproterozoic, and Early Ediacaran core and rim ages indicating that the magmas also assimilated Meso- and Neoproterozoic crustal material prior to final crystallization. The mafic rocks witnessed higher metamorphic grade than associated Ordovician rocks, which are unmetamorphosed or only affected by anchimetamorphism. The gabbros are mostly tholeiitic and enriched in Zr, Th, as well as other incompatible elements and have εNd t=540Ma ranging from 1.3 to 7.4 with most of the values between 5 and 7. 147Sm/144Nd ratios show evidence of weak crustal contamination. The mafic rocks do not reveal any affinity to mid-ocean ridge basalts in their geochemistry but point instead to an emplacement in an active plate margin arc environment. Chromites from ultramafic rocks show typical Ti, Al, Cr#, Fe3+ abundances found in magmatic arc rocks. The formation of the gabbros and the associated ultramafic rocks in the southern Argentine Puna is related to the evolution of the margin of the Pampia terrane, including the Puncoviscana basin, during the Late Neoproterozoic and earliest Cambrian. In contrast to previous interpretations, the rocks predate the Ordovician evolution of the Central proto-Andean active margin. Consequently, interpretations assuming these rocks to represent an oceanic terrane suture of Ordovician age have to be dismissed as much as all palaeotectonic models that define Ordovician terranes in the Central Andes based on assumption that the ultramafic rocks and gabbros exposed in the southern Puna mark plate boundaries. 相似文献
44.
45.
Hemant Balwant Wakode Dibyendu Dutta V. R. Desai Klaus Baier Rafig Azzam 《Arabian Journal of Geosciences》2013,6(2):395-408
Geographical Information System (GIS) have proved to be an efficient tool in the delineation of drainage pattern for water resources management and its planning. In this study, GIS and image processing techniques have been adopted for the identification of morphological features and analyzing the properties of the upper catchment of Kosi River. The basin area includes the high-altitude Himalayan Mountains, including Mount Everest and Kanchenjunga peaks. This basin is the main contributing area for devastating floods in 2008 in the Bihar state of India. The catchment can be divided into three sub-catchments, namely, Arun, Sunkosi, and Tamur. A morphometric analysis shows the nature of drainage in the upper catchment of Kosi River and some causes behind the high-intensity floods by comparing the properties of these three sub-catchments. It shows that the highest-order drains are present in both Arun and Sunkosi and the length of the first-order drains is very high (6,088 km) due to the absence of vegetation and also due to the barren/rocky surface which has tremendous potential to generate runoff. Due to highest mean channel gradient in Tamur sub-basin compared to others, it has the highest flow kinetic velocity. Also, the results show that the Arun sub-catchment has the highest potential to contribute runoff and sediment. One of the major causes behind the high intensity of floods is that the sub-catchments Arun and Sunkosi have a nearly equal time of concentration, so they contribute their peak floods at the same time and hence double the intensity of floods. 相似文献
46.
Klaus J. Stetzenbach Irene M. Farnham Vernon F. Hodge Kevin H. Johannesson 《水文研究》1999,13(17):2655-2673
Groundwater samples were collected from 11 springs in Ash Meadows National Wildlife Refuge in southern Nevada and seven springs from Death Valley National Park in eastern California. Concentrations of the major cations (Ca, Mg, Na and K) and 45 trace elements were determined in these groundwater samples. The resultant data were subjected to evaluation via the multivariate statistical technique principal components analysis (PCA), to investigate the chemical relationships between the Ash Meadows and Death Valley spring waters, to evaluate whether the results of the PCA support those of previous hydrogeological and isotopic studies and to determine if PCA can be used to help delineate potential groundwater flow patterns based on the chemical compositions of groundwaters. The results of the PCA indicated that groundwaters from the regional Paleozoic carbonate aquifers (all of the Ash Meadows springs and four springs from the Furnace Creek region of Death Valley) exhibited strong statistical associations, whereas other Death Valley groundwaters were chemically different. The results of the PCA support earlier studies, where potentiometric head levels, δ18O and δD, geological relationships and rare earth element data were used to evaluate groundwater flow, which suggest groundwater flows from Ash Meadows to the Furnace Creek springs in Death Valley. The PCA suggests that Furnace Creek groundwaters are moderately concentrated Ash Meadows groundwater, reflecting longer aquifer residence times for the Furnace Creek groundwaters. Moreover, PCA indicates that groundwater may flow from springs in the region surrounding Scotty's Castle in Death Valley National Park, to a spring discharging on the valley floor. The study indicates that PCA may provide rapid and relatively cost‐effective methods to assess possible groundwater flow regimes in systems that have not been previously investigated. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
47.
In order to meet the challenge of climate change while allowing for continued economic development, the world will have to
adopt a net zero carbon energy infrastructure. Due to the world’s large stock of low-cost fossil fuels, there is strong motivation
to explore the opportunities for capturing the CO2 that is produced in the combustion of fossil fuels and keeping it out of the atmosphere. Three distinct sets of technologies
are needed to allow for climate neutral use of fossil fuels: (1) capture of CO2 at concentrated sources like electric power plants, future hydrogen production plants and steel and cement plants; (2) capture
of CO2 from the air; and (3) the safe and permanent storage of CO2 away from the atmosphere. A strong regime of carbon accounting is also necessary to gain the public’s trust in the safety
and permanence of CO2 storage. This paper begins with an extensive overview of carbon capture and storage technologies, and then presents a vision
for the potential implementation of carbon capture and storage, drawing upon new ideas such as air capture technology, leakage
insurance, and monitoring using a radioactive isotope such as C-14. These innovations, which may provide a partial solution
for managing the risks associated with long-term carbon storage, are not well developed in the existing literature and deserve
greater study. 相似文献
48.
49.
Aubrite meteorites are composed of constituents which are almost certainly of igneous origin. If they were generated by the melting and fractionation of enstatite chondrite-like parental material, as seems very likely, then plagioclase-rich, basaltic complements to the aubrites should have formed. However, such materials are not known as individual meteorites, and the compositions of two plagioclase-silica clasts and one albite-silica-(diopside-anorthite) clast (probably an impact melt) in the Norton County aubrite breccia suggest that they are not the putative enstatite-plagioclase basalts. We propose a new mechanism that explains the absence of these materials, showing that the expansion of even very small amounts of volatiles present in a melt approaching the surface of a small, low-gravity body will be enough to disrupt the melt into a spray of droplets moving faster than the local escape velocity. This explosive volcanic process of melt removal requires larger melt volatile contents on larger bodies, and data on the solubility of volatiles in basaltic melts suggest that the process was limited to bodies smaller than about 100 km in radius. 相似文献
50.