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81.
Amin Shaban 《Water Resources Management》2009,23(10):1875-1891
Change in climate conditions has become a global issue that has given a serious concern by many researchers. However, the
availability of data in this regard is considered as a major element for optimum comparative analysis. The Mediterranean region
is influenced by climate change, which is reflected mainly by its impact on water sources supply and flow regime. In Lebanon,
these water sources are witnessing obvious quantitative decrease, thus affected the supply side, the so-called “hydrologic
drought”. Therefore, many studies have been made to figure out a comprehensive understanding on water resources in Lebanon
and their interrelation with climatic trends, but they often analyze one component of the water cycle. This study involves
different indices of surface and subsurface water, thus, followed a comparative analysis of different hydrologic records.
This was achieved by applying graphical illustrations of the numerical values adopted from available records. In this regard,
different tools of analysis were used, and more certainly remotely sensed data were helpful for monitoring approaches. Therefore,
results of the obtained comparative analysis revealed a clear regression in the amount of available water from different sources
in Lebanon. These sources, which are under the impact of human like rivers and groundwater, showed a 23–29% decrease in the
amounts of water since the last four decades. While sources, with less human interference, like snow cover and precipitation
have been decreased by 12–16%. However, in both cases, the status is quite alarming and needs immediate water management plans
to conserve water resources in Lebanon. 相似文献
82.
Climate change can lead to a substantial reduction of the strength of the thermohaline circulation in the world oceans. This is often thought to have severe consequences particularly on the North Atlantic region and Northern and Western Europe. The integrated assessment model FUND is used to estimate the extent of these impacts. The results indicate that, owing to a slower warming (rather than cooling) of the regions most affected by a thermohaline circulation collapse, climate change induced damages in these regions would be smaller in case of a shutdown of the thermohaline circulation. However, even with a thermohaline circulation collapse, the total and marginal impacts of climate change are negative.JEL Classification:
Q510, Q540We are grateful to Till Kuhlbrodt for providing the CLIMBER data and to Andre Krebber for processing them. The German Federal Ministry for Education and Research through the INTEGRATION project, the US National Science Foundation through the Center for Integrated Study of the Human Dimensions of Global Change (SBR-9521914) and the Michael Otto Foundation provided welcome financial support. 相似文献
83.
Morgan M. Steffen B. Shafer Belisle Sue B. Watson Gregory L. Boyer Steven W. Wilhelm 《Journal of Great Lakes research》2014
The Laurentian Great Lakes are among the most prominent sources of fresh water in the world. Lake Erie's infamous cyanobacterial blooms have, however, threatened the health of this valuable freshwater resource for decades. Toxic blooms dominated by the cyanobacterium Microcystis aeruginosa have most recently been one of primary ecological concerns for the lake. These toxic blooms impact the availability of potable water, as well as public health and revenues from the tourism and fishery industries. The socioeconomic effects of these blooms have spurred research efforts to pinpoint factors that drive bloom events. Despite decades of research and mitigation efforts, these blooms have expanded both in size and duration in recent years. However, through continued joint efforts between the Canadian and United States governments, scientists, and environmental managers, identification of the factors that drive bloom events is within reach. This review provides a summary of historical and contemporary research efforts in the realm of Lake Erie's harmful cyanobacterial blooms, both in terms of experimental and management achievements and insufficiencies, as well as future directions on the horizon for the lake's research community. 相似文献
84.
Farmers’ risk preferences play an important role in agricultural production decisions. This study characterizes risk preferences among farmers in Yongqiao and determines how these risk preferences are related to their choices regarding climate change adaptation strategies. We find that most farmers in the study area were aware of climate change. They were taking measures to protect their livelihoods against perceived changes to the local climate. The risk experiment result shows that the representative subject was risk averse, and women were more risk averse than men. The relationships between farmers’ risk preferences and different climate change adaptation choices were different. Farmers’ risk aversion was negatively and significantly related with adaptation strategies on planting new crop varieties and adopting new technology, but it had a significantly positive effect on purchasing weather index crop insurance. The results also indicate that the level of education, farming experience, farm size, household income and perception of climate change impacts influence farmers’ adaptation decisions. 相似文献
85.
Data Envelopment Analysis of different climate policy scenarios 总被引:1,自引:0,他引:1
Recent developments in the political, scientific and economic debate on climate change suggest that it is of critical importance to develop new approaches able to compare policy scenarios for their environmental effectiveness, their distributive effects, their enforceability, their costs and many other dimensions. This paper discusses a quantitative methodology to assess the relative performance of different climate policy scenarios when accounting for their long-term economic, social and environmental impacts. The proposed procedure is based on Data Envelopment Analysis, here employed in evaluating the relative efficiency of eleven global climate policy scenarios. The methodology provides a promising comparison framework; it can be seen as a way of setting some basic guidelines to frame further debates and negotiations and can be flexibly adopted and modified by decision makers to obtain relevant information for policy design. Three major findings emerge from this analysis: (i) stringent climate policies can outperform less ambitious proposals if all sustainability dimensions are taken into account; (ii) a carefully chosen burden-sharing rule is able to bring together climate stabilisation and equity considerations; and (iii) the most inefficient strategy results from the failure to negotiate a post-2012 global climate agreement. 相似文献
86.
The growing concerns of climate change require implementing measures to quantify, to monitor and to minimize greenhouse gas (GHG) emissions. Nonetheless, most of the measures available are not easy to define or execute because they rely on current emissions and have a corrective character. To address this issue, a methodology to characterize GHG emissions that allows implementing preventive measures is proposed in this paper. The methodology is related to household urban planning procedures and considers urban infrastructures to characterize GHG emissions and to execute preventive measures based on sustainability design criteria. The methodology has been tested by applying it to a set of medium-sized municipalities with average GHG emissions from 6,822.32 kgCO2eq/year to 5,913.79 kgCO2eq/year for every residential unit. The results indicate that the greatest pollutant source is transport, especially in the issuance of street network design, followed by gas and electricity consumption. The average undevelopable land area required for the complete GHG emissions capture amounts to 3.42 m2 of undevelopable land for every m2 of urbanizable land and 9.02 m2 of undevelopable land for every m2 of built land. 相似文献
87.
Thomas P. Tomich Meine van Noordwijk Stephen A. Vosti Julie Witcover 《Agricultural Economics》1998,19(1-2):159-174
Forests continue to fall for agricultural purposes throughout the humid tropics, with immediate and potentially large consequences for climate change and biodiversity loss-issues of key interest to the international community. Some of the actors directly responsible for forest conversion fell trees to meet food security needs and alleviate poverty-issues of urgent interest to them and also to national policymakers. This multiplicity of groups with differing (often conflicting) interests in the multifarious goods and services produced by tropical forests complicates the search for alternative agricultural activities for forest margins since these alternatives must satisfy such divergent objectives. This paper sets out a conceptual framework for comparing the impacts of different land use systems and agricultural practices at the margins of tropical rainforests in terms of the concerns and objectives of two key interest groups: small-scale farmers seeking livelihoods at the forest margins and the ‘international’ interests in the global public goods and services supplied by tropical rainforests. This framework should be useful to a third key group, the national and regional policymakers who must consider these and other policy objectives and then decide on courses of action. The paper identifies data needs and analytical methods capable of supplying an empirical base for this conceptual framework, based on quantifiable indicators. It then presents preliminary results of the application of this conceptual framework in Indonesia and Brazil in association with a global, collaborative, multidisciplinary research program. Even using preliminary order-of-magnitude estimates (to be replaced by more precise measurements as they become available), this conceptual framework presents results in ways that allow researchers and policymakers to select clear ‘best bets’ for development, when they exist, and to assess tradeoffs and options for complementary policy action and research efforts, when they do not. 相似文献
88.
Sediment cores from Lake Qarun provide a record of mid-late Holocene climatic changes in Northern and Eastern Africa as well as environmental changes due to the activities of ancient Egyptians. We used sedimentological, mineralogical, and geochemical analyses of the cores to investigate long-term variations in lake level due to changing hydrologic inputs. An age model based on three paired 14C and paleomagnetic measurements suggests that the base of the sediment cores is as old as ∼ 5000 B.C.E. Geochemical analyses indicated that lake sediments were derived from Nile floods with an admixture of Saharan sand. Laminated endogenic carbonate-rich clayey silt lithofacies with benthic diatoms are indicative of relatively low lake levels, saline waters and dry conditions; massive lithofacies with planktonic diatom species are indicative of relatively high lake levels, fresh waters and humid conditions. Faintly laminated clayey silt lithofacies suggest intermediate conditions. Variations in lithology as well as diatom composition suggest that the lake level has varied from relatively high levels in its early history to lower levels in later years although there have been numerous cycles in water level over the past 7000 years. A combination of climate changes in the source area of the Nile River as a result of monsoon dynamics; climatic changes in the setting area of the Lake Qarun; and human activities through the dynasties in Egypt produced these variations in lake level. 相似文献
89.
David Henderson 《Economic Affairs》2009,29(3):87-88
(The text which follows formed the basis for a brief presentation to a conference held on 22 April 2009 at the Said Business School, Oxford University. The subject of the conference was 'Beyond Kyoto – Green Innovation and Enterprise in the 21st Century'.)
Governments across the world are mishandling climate change issues. The content, the orientation, and in particular the basis and rationale of current policies to curb emissions of (so-called) 'greenhouse gases', are all open to serious question. 相似文献
Governments across the world are mishandling climate change issues. The content, the orientation, and in particular the basis and rationale of current policies to curb emissions of (so-called) 'greenhouse gases', are all open to serious question. 相似文献
90.
The study is one of the first concerned with the topic of accounting and climate change adaptation. It proposes that the accounting role can support organisational climate change adaptation by performing the following functions: (i) a risk assessment function (assessing vulnerability and adaptive capacity), (ii) a valuation function (valuing adaptation costs and benefits) and (iii) a disclosure function (disclosure of risk associated with climate change impacts). This study synthesises and expands on existing research and practice in environmental accounting and sets the scene for future research and practice in the emerging area of accounting for climate risk. 相似文献