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This study builds on an earlier analysis of resilience of India and Indian states to climate change. The previous study (Brenkert and Malone, Clim Change 72:57–102, 2005) assessed current resilience; this research uses the Vulnerability–Resilience Indicators Model (VRIM) to project resilience to 2095 and to perform an uncertainty analysis on the deterministic results. Projections utilized two SRES-based scenarios, one with fast-and-high growth, one with delayed growth. A detailed comparison of two states, the Punjab and Orissa, points to the kinds of insights that can be obtained using the VRIM. The scenarios differ most significantly in the timing of the uncertainty in economic prosperity (represented by GDP per capita) as a major factor in explaining the uncertainty in the resilience index. In the fast-and-high growth scenario the states differ most markedly regarding the role of ecosystem sensitivity, land use and water availability. The uncertainty analysis shows, for example, that resilience in the Punjab might be enhanced, especially in the delayed growth scenario, if early attention is paid to the impact of ecosystems sensitivity on environmental well-being of the state. By the same token, later in the century land-use pressures might be avoided if land is managed through intensification rather than extensification of agricultural land. Thus, this methodology illustrates how a policy maker can be informed about where to focus attention on specific issues, by understanding the potential changes at a specific location and time—and, thus, what might yield desired outcomes. Model results can point to further analyses of the potential for resilience-building. 相似文献
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Barbara J. Thompson Sarah E. Gibson Peter C. Schroeder David F. Webb Charles N. Arge Mario M. Bisi Giuliana de Toma Barbara A. Emery Antoinette B. Galvin Deborah A. Haber Bernard V. Jackson Elizabeth A. Jensen Robert J. Leamon Jiuhou Lei Periasamy K. Manoharan M. Leila Mays Patrick S. McIntosh Gordon J. D. Petrie Simon P. Plunkett Liying Qian Peter Riley Steven T. Suess Munetoshi Tokumaru Brian T. Welsch Thomas N. Woods 《Solar physics》2011,274(1-2):29-56
We present an overview of the data and models collected for the Whole Heliosphere Interval, an international campaign to study the three-dimensional solar?Cheliospheric?Cplanetary connected system near solar minimum. The data and models correspond to solar Carrington Rotation 2068 (20 March??C?16 April 2008) extending from below the solar photosphere, through interplanetary space, and down to Earth??s mesosphere. Nearly 200 people participated in aspects of WHI studies, analyzing and interpreting data from nearly 100 instruments and models in order to elucidate the physics of fundamental heliophysical processes. The solar and inner heliospheric data showed structure consistent with the declining phase of the solar cycle. A closely spaced cluster of low-latitude active regions was responsible for an increased level of magnetic activity, while a highly warped current sheet dominated heliospheric structure. The geospace data revealed an unusually high level of activity, driven primarily by the periodic impingement of high-speed streams. The WHI studies traced the solar activity and structure into the heliosphere and geospace, and provided new insight into the nature of the interconnected heliophysical system near solar minimum. 相似文献
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Assessment of groundwater recharge processes through karst vadose zone by cave percolation monitoring 
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下载免费PDF全文 Amaël Poulain Arnaud Watlet Olivier Kaufmann Michel Van Camp Hervé Jourde Naomi Mazzilli Gaëtan Rochez Romain Deleu Yves Quinif Vincent Hallet 《水文研究》2018,32(13):2069-2083
Recharge processes of karst aquifers are difficult to assess given their strong heterogeneity and the poorly known effect of vadose zone on infiltration. However, recharge assessment is crucial for the evaluation of groundwater resources. Moreover, the vulnerability of karst aquifers depends on vadose zone behaviour because it is the place where most contamination takes place. In this work, an in situ experimental approach was performed to identify and quantify flow and storage processes occurring in karst vadose zone. Cave percolation monitoring and dye tracing were used to investigate unsaturated zone hydrological processes. Two flow components (diffuse and quick) were identified and, respectively, account for 66% and 34% of the recharge. Quickflow was found to be the result of bypass phenomenon in vadose zone related to water saturation. We identify the role of epikarst as a shunting area, most of the storage in the vadose zone occurring via the diffuse flow component in low permeability zones. Relationship between rainfall intensity and transit velocity was demonstrated, with 5 times higher velocities for the quick recharge mode than the diffuse mode. Modelling approach with KarstMod software allowed to simulate the hybrid recharge through vadose zone and shows promising chances to properly assess the recharge processes in karst aquifer based on simple physical models. 相似文献
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Projected increased risk of water deficit over major West African river basins under future climates
Mouhamadou Bamba Sylla Aissatou Faye Nana Ama Browne Klutse Kangbeni Dimobe 《Climatic change》2018,149(2):247-260
Despite decades of research, large multi-model uncertainty remains about the Earth’s equilibrium climate sensitivity to carbon dioxide forcing as inferred from state-of-the-art Earth system models (ESMs). Statistical treatments of multi-model uncertainties are often limited to simple ESM averaging approaches. Sometimes models are weighted by how well they reproduce historical climate observations. Here, we propose a novel approach to multi-model combination and uncertainty quantification. Rather than averaging a discrete set of models, our approach samples from a continuous distribution over a reduced space of simple model parameters. We fit the free parameters of a reduced-order climate model to the output of each member of the multi-model ensemble. The reduced-order parameter estimates are then combined using a hierarchical Bayesian statistical model. The result is a multi-model distribution of reduced-model parameters, including climate sensitivity. In effect, the multi-model uncertainty problem within an ensemble of ESMs is converted to a parametric uncertainty problem within a reduced model. The multi-model distribution can then be updated with observational data, combining two independent lines of evidence. We apply this approach to 24 model simulations of global surface temperature and net top-of-atmosphere radiation response to abrupt quadrupling of carbon dioxide, and four historical temperature data sets. Our reduced order model is a 2-layer energy balance model. We present probability distributions of climate sensitivity based on (1) the multi-model ensemble alone and (2) the multi-model ensemble and observations. 相似文献
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In this paper we present the initial results from a project to develop a population health model so we can extend the scenarios
included in the IPCC’s Special Report on Emission Scenarios to include population health status. Our initial hypothesis was
that some climatic variable, particularly temperature, would have a significant impact on health outcomes. After experiments
– using the Global Burden of Disease (GBD) data on Years of Life Lost (YLL) and Years Lived with disability (YLD) both by
WHO region and by five degree latitude band as outcome variables – failed, we settled on life expectancy (LE) as the best
measure of health status. We discovered that there is a solid relationship between LE and the GBD data from our first experiments,
allowing us to extend the results from the LE model. The LE model used cross section data on LE for 91 countries and included
temperature, per capita income, access to clean water and sanitation, literacy, simple medical attention, nutrition, per capita
medical expenditure, electricity use per capita, and automobiles per capita as independent variables. While all were individually
associated with LE, our model of choice included literacy, access to clean water and sanitation, simple medical attention,
an indictor variable for Sub-Saharan Africa and purchasing-power parity per capita income. Note that neither temperature nor
calories enter into this model. The fit between life expectancy, as predicted by this model, and actual life expectancy was
quite good (R
2 =0.90), except for Rwanda, Uganda, and Madagascar; these countries accounted for one half of the unexplained variation in
the model. The LE model was then used to develop trajectories of life expectancy in India for the four IPCC SRES storylines,
where values for the independent variables were extrapolated based on the story line content. YLL and YLD estimates were created
using the current cross relationship of these outcomes to LE. Given the lack of a general role for climate in our LE model,
future work is planned to explore how to add detailed climate related impacts, to explore alternative nutritional variables,
as well as extend the data set to allow a cross-section time-series approach. 相似文献
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Antoinette M. Mannion 《GeoJournal》1993,31(4):347-354
Biotechnology is the manipulation of organisms to carry out specific processes. It has various applications that are relevant to many aspects of geography. At a fundamental level biotechnology is directed at manipulating energy flows, especially those in agriculture. Improved crop varieties, disease and pest control, as well as nutrient enhancement can all be achieved by biotechnology, culminating in increased agricultural productivity. There are significant environmental advantages though there are also constraints imposed by economic considerations. Mineral extraction, metal recycling and pollution abatement can also be improved by biotechnology which thus contributes to more efficient resource use and enhanced environmental quality. Food and fuel energy, notably biomass fuels, can also be so produced. The manifold implications of this technology for earth and social sciences thus require its inclusion in geographical studies. 相似文献
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Isolation and characterization of Aeromonas species were undertaken in the Ebrié lagoon (Abidjan, Côte d’Ivoire) over a one year period. Overall 63% of 501 water samples were identified as positive for Aeromonas spp. A. sobria, A. hydrophila and A. caviae represent respectively 49.20%, 20.63% and 30.15% of the positive samples. Thirty nine of the positive samples were recovered from surface water samples; while 24 bottom water samples were positive for Aeromonas. Aeromonas species are most frequently (82.53) present in the Ebrié lagoon urban area during the rainy and flood seasons when the salinity is low and below 10‰. A lower isolation frequency is noticed during the dry season when water salinity is over 10‰. Finally, a higher isolation frequency occurred in samples with highest counts of Escherichia coli. 相似文献
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Antoinette Tordesillas Sebastian Pucilowski David M. Walker John F. Peters Laura E. Walizer 《国际地质力学数值与分析法杂志》2014,38(12):1247-1275
Recent analysis of data from triaxial tests on sand and discrete element simulations indicate the final pattern of failure is encoded in grain motions during the nascent stages of loading. We study vortices that are evident from grain displacements at the start of loading and bear a direct mathematical connection to boundary conditions, uniform continuum strain and shear bands. Motions of three grains in mutual contact, that is, 3‐cycles, manifest vortices. In the initial stages of loading, 3‐cycles initiate a rotation around a region Ω* where the shear band ultimately develops. This bias sets a course in 3‐cycle evolution, determining where they will more likely collapse. A multiscale spatial analysis of 3‐cycle temporal evolution provides quantitative evidence that the most stable, persistent 3‐cycles degrade preferentially in Ω*, until essentially depleted when the shear band is fully formed. The transition towards a clustered distribution of persistent 3‐cycles occurs early in the loading history—and coincides with the persistent localisation of vortices in Ω*. In 3D samples, no evidence of spatial clustering in persistent 3‐cycle deaths is found in samples undergoing diffuse failure, while early clustering manifests in a sample that ultimately failed by strain localisation. This study not only delivered insights into the possible structural origins of vortices in dense granular systems but also a tool for the early detection of the mode of failure—localised versus diffuse—a sample will ultimately undergo. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献