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61.
Romero Jorge E. Vergara-Pinto Francisca Aguilar Germn Garcs Alex Montserrat Santiago 《Landslides》2022,19(4):865-883
Landslides - An extreme precipitation event produced catastrophic debris flows in central Chile during 29–31 January 2021 (austral summer). Our study focuses on the triggering factors and... 相似文献
62.
Multi-factor impact analysis of agricultural production in Bangladesh with climate change 总被引:1,自引:0,他引:1
Alex C. Ruane David C. Major Winston H. Yu Mozaharul Alam Sk. Ghulam Hussain Abu Saleh Khan Ahmadul Hassan Bhuiya Md. Tamim Al Hossain Richard Goldberg Radley M. Horton Cynthia Rosenzweig 《Global Environmental Change》2013,23(1):338-350
Diverse vulnerabilities of Bangladesh's agricultural sector in 16 sub-regions are assessed using experiments designed to investigate climate impact factors in isolation and in combination. Climate information from a suite of global climate models (GCMs) is used to drive models assessing the agricultural impact of changes in temperature, precipitation, carbon dioxide concentrations, river floods, and sea level rise for the 2040–2069 period in comparison to a historical baseline. Using the multi-factor impacts analysis framework developed in Yu et al. (2010), this study provides new sub-regional vulnerability analyses and quantifies key uncertainties in climate and production. Rice (aman, boro, and aus seasons) and wheat production are simulated in each sub-region using the biophysical Crop Environment REsource Synthesis (CERES) models. These simulations are then combined with the MIKE BASIN hydrologic model for river floods in the Ganges-Brahmaputra-Meghna (GBM) Basins, and the MIKE21 Two-Dimensional Estuary Model to determine coastal inundation under conditions of higher mean sea level. The impacts of each factor depend on GCM configurations, emissions pathways, sub-regions, and particular seasons and crops. Temperature increases generally reduce production across all scenarios. Precipitation changes can have either a positive or a negative impact, with a high degree of uncertainty across GCMs. Carbon dioxide impacts on crop production are positive and depend on the emissions pathway. Increasing river flood areas reduce production in affected sub-regions. Precipitation uncertainties from different GCMs and emissions scenarios are reduced when integrated across the large GBM Basins’ hydrology. Agriculture in Southern Bangladesh is severely affected by sea level rise even when cyclonic surges are not fully considered, with impacts increasing under the higher emissions scenario. 相似文献
63.
Alex Ruzicka Jeffrey N. Grossman Laurence Garvie 《Meteoritics & planetary science》2014,49(8):E1-E101
Meteoritical Bulletin 100 contains 1943 meteorites including 8 falls (Boumdeid [2011], Huaxi, Ko?ice, Silistra, So?tmany, Sutter's Mill, Thika, Tissint), with 1575 ordinary chondrites, 139 carbonaceous chondrites, 96 HED achondrites, 25 ureilites, 18 primitive achondrites, 17 iron meteorites, 15 enstatite chondrites, 11 lunar meteorites, 10 mesosiderites, 10 ungrouped achondrites, 8 pallasites, 8 Martian meteorites, 6 Rumuruti chondrites, 3 enstatite achondrites, and 2 angrites, and with 937 from Antarctica, 592 from Africa, 230 from Asia, 95 from South America, 44 from North America, 36 from Oceania, 6 from Europe, and 1 from an unknown location. This will be the last Bulletin published in the current format. Information about approved meteorites can be obtained from the Meteoritical Bulletin Database (MBD) available online at http://www.lpi.usra.edu/meteor/ 相似文献
64.
Alex Schwartz 《The Professional geographer》1987,39(2):166-172
An increasing number of studies of business start-ups, closings, and relocations rely on a single data base, DUNS Market Identifiers. This data file to U.S. business establishments provides researchers with essential information about individual firms and establishments. It also exhibits serveral idiosyncracies and requires careful consideration of the meaning of such basic terms as “location”and “firm.”Drawing from a recent survey of 500 New Jersey firms. I consider some of the methodological amd conceptual issues Dun and Bradstreet data pose for industrial location analysts. The Dun and Bradstreet listings exaggerate the exaggerate the incidence and magnitude of establishment openings and closing. 相似文献
65.
Abstract— We analyzed the Steinbach IVA stony‐iron meteorite using scanning electron microscopy (SEM), electron microprobe analysis (EMPA), laser ablation inductively‐coupled‐plasma mass spectroscopy (LA‐ICP‐MS), and modeling techniques. Different and sometimes adjacent low‐Ca pyroxene grains have distinct compositions and evidently crystallized at different stages in a chemically evolving system prior to the solidification of metal and troilite. Early crystallizing pyroxene shows evidence for disequilibrium and formation under conditions of rapid cooling, producing clinobronzite and type 1 pyroxene rich in troilite and other inclusions. Subsequently, type 2 pyroxene crystallized over an extensive fractionation interval. Steinbach probably formed as a cumulate produced by extensive crystal fractionation (?60–70% fractional crystallization) from a high‐temperature (?1450–1490 °C) silicate‐metallic magma. The inferred composition of the precursor magma is best modeled as having formed by ≥30–50% silicate partial melting of a chondritic protolith. If this protolith was similar to an LL chondrite (as implied by O‐isotopic data), then olivine must have separated from the partial melt, and a substantial amount (?53–56%) of FeO must have been reduced in the silicate magma. A model of simultaneous endogenic heating and collisional disruption appears best able to explain the data for Steinbach and other IVA meteorites. Impact disruption occurred while the parent body was substantially molten, causing liquids to separate from solids and oxygen‐bearing gas to vent to space, leading to a molten metal‐rich body that was smaller than the original parent body and that solidified from the outside in. This model can simultaneously explain the characteristics of both stony‐iron and iron IVA meteorites, including the apparent correlation between metal composition and metallographic cooling rate observed for metal. 相似文献
66.
67.
68.
VOCs in Ground Water Influenced by Large Scale Withdrawals 总被引:1,自引:0,他引:1
69.
Wolf Uwe REIMOLD Christian KOEBERL Robert M. HOUGH Iain MCDONALD Alex BEVAN Kassa AMARE Bevan M. FRENCH 《Meteoritics & planetary science》2003,38(7):1109-1130
Abstract— The large, complex Woodleigh structure in the Carnarvon basin of Western Australia has recently been added to the terrestrial impact crater record. Many aspects of this structure are, however, still uncertain. This work provides a detailed petrographic assessment of a suite of representative drill core samples from the borehole Woodleigh 1 that penetrated uplifted basement rocks of the central part of this structure. Fundamental rock and mineral deformation data and high‐precision chemical data, including results of PGE and oxygen isotopic analysis, are presented. The sampled interval displays likely impact‐produced macrodeformation in the form of fracturing and breccia veining at the microscopic scale. Contrary to earlier reports that these breccias represent pseudotachylite (friction melt) or even shock/shear‐produced pseudotachylitic melt breccia cannot be confirmed due to pervasive post‐impact alteration. Abundant planar deformation features (PDFs) in quartz, in addition to diaplectic glass and partial isotropization, are the main shock deformation effects observed, confirming that Woodleigh is of impact origin. Over the investigated depth interval, the statistics of quartz grains with a variable number of sets of PDFs does not change significantly, and the patterns of crystallographic orientations of PDFs in randomly selected quartz grains does not indicate a change in absolute shock pressure with depth either. The value of oxygen isotopes for the recognition of meteoritic contamination, as proposed by earlier Woodleigh workers, is critically assessed. Neither INA nor PGE analyses of our samples support the presence of a meteoritic component within this basement section, as had been claimed in earlier work. 相似文献
70.
This paper explores the links between economic growth and the impacts of climate change. Inclusive, pro-poor growth is central to the development of low-income countries. There is also a broad consensus that growth and development are important to reduce vulnerability to climate change. Growth does not automatically reduce vulnerability, only the right kind of growth does. The paper aims to develop a better understanding of what the ??right kind of growth?? may be. We find that many growth policies, such as investment in skills and access to finance, indeed reduce vulnerability to climate change. However, climate change calls for some adjustments in growth policy. In particular, investment in infrastructure and efforts to stimulate entrepreneurship and competitive markets must take more of a risk management perspective and recognise climate risks. 相似文献