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Projections of climate impacts on crop yields simulated for different General Circulation Model (GCM) scenarios are used, in a recursively dynamic general equilibrium framework, to account for potential economy-wide impacts of climate change in Egypt. Comparing these impact projections to those obtained under a reference, business-as-usual, scenario assuming some moderate changes in the political, economic or technological spheres, indicates that global warming has potentially negative effects. The analysis is based on a global assessment of potential climate change-induced variations in world commodity production and trade. The Egyptian agricultural sector, and the non-agricultural sector to a lesser extent, are projected to be increasingly less self-sufficient. Specific potential adverse impacts are identified. The simulation results show that high-cost adaptation measures involving major changes in the agricultural system and practices may mitigate these adverse impacts. Stimulating economic development of the rural areas and creating appropriate conditions for effective diffusion and development of technologies — particularly for the agricultural sector — would seem a desirable strategy. Perhaps, more importantly, the simulation results show that the assumption of exogenously determined technological progress may be inappropriate, in which case the potential adverse impacts of a future warming of the global climate are likely to be fewer than is indicated in this study — if prevailing constraints on productivity growth in the major food and feed grains are ‘released’ by endogenous advances in technology. 相似文献
365.
Aimé Druilhet Pierre Durand Alberte Fischer Frédérique Said 《Boundary-Layer Meteorology》1990,52(4):397-414
Through simultaneous measurements, it is possible to demonstrate the relation between sea swell and surface temperature as measured by a thermoradiometer onboard an aircraft. Thermodynamic measurements made on board the aircraft enable analysis of the interaction between swell and surface marine layer dynamics. The cospectral functions of vertical turbulent transfer for sensible and latent heat indicate large-scale dynamic structures which would seem to be initiated by inhomogeneities in the humidity field. A cross-spectral examination of temperature and humidity produces a structure that is common to both parameters and is caused by swell propagation. The data used here were collected during the TOSCANE-T experiment, whose aim was to validate remote sensing scatterometer techniques, by means of an instrumented aircraft designed for atmospheric research. 相似文献
366.
Patterns of the typical groundwater quality for 13 hydrogeological units (lithofacies units) of the solid rock and for 5 stages of the contamination of groundwater by the agricultural production are derived from investigations carried out in six regions serving as examples and in evaluation of data series covering many years. The concentration values of the substances contained in water constituting the lower and upper limits of the typical width of variation are regarded as the quality of the groundwater reservoir (long retention time) and a fast runoff component of groundwater. On the basis of this model conception it is possible to determine one of the following four quantities from the other three quantities: groundwater quality, size of the groundwater reservoir, groundwater runoff with the shares of the slow component and of the fast one, removal of substances out of the root zone. 相似文献
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G. Fischer 《International Journal of Earth Sciences》1951,39(1):131-136
Ohne Zusammenfassung 相似文献
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Günther Fischer Tatiana Ermolieva Yuri Ermoliev Laixiang Sun 《Stochastic Environmental Research and Risk Assessment (SERRA)》2009,23(4):441-450
In this paper we show that explicit treatment of risks and uncertainties in agricultural production planning may considerably
alter strategies for achieving robust outcomes with regard to sustainable agricultural developments. We discuss production
planning models under uncertainties and risks that may assist in planning location-specific production expansion within environmental
and health risk indicators and constraints. The proposed approaches are illustrated with the example of spatially explicit
livestock production allocation in China to 2030. 相似文献