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151.
Competing rationalities in water conflict: Mining and the indigenous community in Chiu Chiu,El Loa Province,northern Chile 总被引:1,自引:0,他引:1
Francisco Molina Camacho 《Singapore journal of tropical geography》2012,33(1):93-107
Conflict over water is a significant phenomenon in many parts of the world where globally linked neoliberal economic activities encroach on the lands of indigenous peoples. This case study from Chile examines how water scarcity affecting indigenous agricultural communities in the Chilean Altiplano has been exacerbated by legally sanctioned mining‐related practices. Notably, the legal framing of the 1981 Water Code promotes private ownership of water rights and enhanced mining activity usually at the expense of the ancestral territorial rights of indigenous communities. In the case of the Atacameño community of Chiu Chiu, a serious decrease in subsistence and agriculture production has been suffered as a consequence of reduced flow in the Loa River, resulting from the water intensive needs and extraction practices of the nearby Chuquicamata mine owned by Codelco, the National Copper Corporation of Chile. Via an analysis of the political ecology of competing rationalities this paper explores how an economic rationality based on utilitarian and reductionist thinking manifested by Codelco has taken precedence locally over a socionatural rationality grounded in holistic thinking and sustainability concerns as articulated by the Chiu Chiu community. 相似文献
152.
Francisco Estrada Benjamín Martínez-López Cecilia Conde Carlos Gay-García 《Climatic change》2012,110(3-4):1029-1046
This paper presents a review of the methodology applied for generating the regional climate change scenarios utilized in important National Documents of Mexico, such as the Fourth National Communication to the United Nations Framework Convention on Climate Change, the Fourth National Report to the Convention on Biological Diversity and The Economics of Climate Change in Mexico. It is shown that these regional climate change scenarios, which are one of the main inputs to support the assessments presented in these documents, are an example of the erroneous use of statistical downscaling techniques. The arguments presented here imply that the work based on such scenarios should be revised and therefore, these documents are inadequate for supporting national decision- making. 相似文献
153.
Extreme climatic events in the Amazon basin 总被引:1,自引:0,他引:1
Jose Antonio Marengo Javier Tomasella Wagner R. Soares Lincoln M. Alves Carlos A. Nobre 《Theoretical and Applied Climatology》2012,107(1-2):73-85
During 2009 the Amazon basin was hit by a heavy flooding with a magnitude and duration few times observed in several decades. Torrential rain in northern and eastern Amazonia during the austral summer of 2008–2009 swelled the Amazon River and its tributaries. By July 2009, water levels of the Rio Negro, a major Amazon tributary, reached at Manaus harbor a new record, the highest mark of the last 107?years. During the 2008–2009 hydrological year, the rainy season on northern and northwestern Amazonia started prematurely, and was followed by a longer-than-normal rainy season. An anomalously southward migration of the ITCZ during May–June 2009, due to the warmer than normal surface waters in the tropical South Atlantic, was responsible for abundant rainfall in large regions of eastern Amazonia and Northeast Brazil from May to July 2009. We also compared the flood of 2009 with other major events recorded in 1989 and 1999. The hydrological consequences of this pattern were earlier than normal floods in Amazon northern tributaries, which peak discharges at their confluences with the main stem almost coincided with the peaks of southern tributaries. Since the time displacement of the contribution to the main stem of northern and southern Amazon tributaries is fundamental for damping flood waves in the main stem, the simultaneous combinations of peak discharges of tributaries resulted in an extreme flood. 相似文献
154.
Decadal prediction skill in a multi-model ensemble 总被引:4,自引:3,他引:1
Geert Jan van Oldenborgh Francisco J. Doblas-Reyes Bert Wouters Wilco Hazeleger 《Climate Dynamics》2012,38(7-8):1263-1280
Decadal climate predictions may have skill due to predictable components in boundary conditions (mainly greenhouse gas concentrations but also tropospheric and stratospheric aerosol distributions) and initial conditions (mainly the ocean state). We investigate the skill of temperature and precipitation hindcasts from a multi-model ensemble of four climate forecast systems based on coupled ocean-atmosphere models. Regional variations in skill with and without trend are compared with similarly analysed uninitialised experiments to separate the trend due to monotonically increasing forcings from fluctuations around the trend due to the ocean initial state and aerosol forcings. In temperature most of the skill in both multi-model ensembles comes from the externally forced trends. The rise of the global mean temperature is represented well in the initialised hindcasts, but variations around the trend show little skill beyond the first year due to the absence of volcanic aerosols in the hindcasts and the unpredictability of ENSO. The models have non-trivial skill in hindcasts of North Atlantic sea surface temperature beyond the trend. This skill is highest in the northern North Atlantic in initialised experiments and in the subtropical North Atlantic in uninitialised simulations. A similar result is found in the Pacific Ocean, although the signal is less clear. The uninitialised simulations have good skill beyond the trend in the western North Pacific. The initialised experiments show some skill in the decadal ENSO region in the eastern Pacific, in agreement with previous studies. However, the results in this study are not statistically significant (p?≈?0.1) by themselves. The initialised models also show some skill in forecasting 4-year mean Sahel rainfall at lead times of 1 and 5?years, in agreement with the observed teleconnection from the Atlantic Ocean. Again, the skill is not statistically significant (p?≈?0.2). Furthermore, uninitialised simulations that include volcanic aerosols have similar skill. It is therefore still an open question whether initialisation improves predictions of Sahel rainfall. We conclude that the main source of skill in forecasting temperature is the trend forced by rising greenhouse gas concentrations. The ocean initial state contributes to skill in some regions, but variations in boundary forcings such as aerosols are as important in decadal forecasting. 相似文献
155.
The Global Paleomonsoon as seen through speleothem records from Asia and the Americas 总被引:3,自引:0,他引:3
Hai Cheng Ashish Sinha Xianfeng Wang Francisco W. Cruz R. Lawrence Edwards 《Climate Dynamics》2012,39(5):1045-1062
The regional monsoons of the world have long been viewed as seasonal atmospheric circulation reversal—analogous to a thermally-driven land-sea breeze on a continental scale. This conventional view of monsoons is now being integrated at a global scale and accordingly, a new paradigm has emerged which considers regional monsoons to be manifestations of global-scale seasonal changes in response to overturning of atmospheric circulation in the tropics and subtropics, and henceforth, interactive components of a singular Global Monsoon (GM) system. The paleoclimate community, however, tends to view ‘paleomonsoon’ (PM), largely in terms of regional circulation phenomena. In the past decade, many high-quality speleothem oxygen isotope (δ18O) records have been established from the Asian Monsoon and the South American Monsoon regions that primarily reflect changes in the integrated intensities of monsoons on orbital-to-decadal timescales. With the emergence of these high-resolution and absolute-dated records from both sides of the Equator, it is now possible to test a concept of the ‘Global-Paleo-Monsoon’ (GPM) on a wide-range of timescales. Here we present a comprehensive synthesis of globally-distributed speleothem δ18O records and highlight three aspects of the GPM that are comparable to the modern GM: (1) the GPM intensity swings on different timescales; (2) their global extent; and (3) an anti-phased inter-hemispheric relationship between the Asian and South American monsoon systems on a wide range of timescales. 相似文献
156.
Francisco Salamanca Andrea Krpo Alberto Martilli Alain Clappier 《Theoretical and Applied Climatology》2010,99(3-4):331-344
The generation of heat in buildings, and the way this heat is exchanged with the exterior, plays an important role in urban climate. To analyze the impact on urban climate of a change in the urban structure, it is necessary to build and use a model capable of accounting for all the urban heat fluxes. In this contribution, a new building energy model (BEM) is developed and implemented in an urban canopy parameterization (UCP) for mesoscale models. The new model accounts for: the diffusion of heat through walls, roofs, and floors; natural ventilation; the radiation exchanged between indoor surfaces; the generation of heat due to occupants and equipments; and the consumption of energy due to air conditioning systems. The behavior of BEM is compared to other models used in the thermal analysis of buildings (CBS-MASS, BLAST, and TARP) and with another box-building model. Eventually, a sensitivity analysis of different parameters, as well as a study of the impact of BEM on the UCP is carried out. The validations indicate that BEM provides good estimates of the physical behavior of buildings and it is a step towards a modeling tool that can be an important support to urban planners. 相似文献
157.
Bernard Fontaine Javier Garcia-Serrano Pascal Roucou Belen Rodriguez-Fonseca Teresa Losada Fabrice Chauvin Sébastien Gervois Sivarajan Sijikumar Paolo Ruti Serge Janicot 《Climate Dynamics》2010,35(1):95-114
Using both empirical and numerical ensemble approaches this study focuses on the Mediterranean/West African relationship in
northern summer. Statistical analyses utilize skin temperature, sea surface temperature, in situ and satellite rainfall, outgoing
longwave radiation (OLR) observations and reanalyzed data winds and specific humidity on isobaric surfaces. Numerical investigations
are based on a large set of sensitivity experiments performed on four atmospheric general circulation models (AGCM): ARPEGE-Climat3,
ECHAM4, LMDZ4 and UCLA7.3. Model outputs are compared to observations, discussed model by model and with an ensemble (multi-model)
approach. As in previous studies the anomalous Mediterranean warm events are associated with specific impacts over the African
monsoon region, i.e., a more intense monsoon, enhanced flux convergence and ascendances around the ITCZ, a strengthening of
low level moisture advection and a more northward location of ascending motion in West Africa. The results show also new features
(1) thermal variability observed in the two Mediterranean basins has unalike impacts, i.e. the western Mediterranean covaries
with convection in Gulf of Guinea, while the eastern Mediterranean can be interpreted as Sahelian thermal-forcing; (2) although
observations show symmetry between warming and cooling, modelling evidences only support the eastern warming influence; (3)
anomalous East warm situations are associated with a more northward migration of the monsoon system accompanied by enhanced
southwertely flow and weakened northeasterly climatological wind; (4) the multi-model response shows that anomalous East warm
surface temperatures generate an enhancement of the overturning circulation in low and high levels, an increase in TEJ (Tropical
Eeasterly Jet) and a decrease in AEJ (African Eeasterly Jet). 相似文献
158.
In this paper, the unfeasibility of producing “objective” probabilistic climate change scenarios is discussed. Realizing that the knowledge of “true” probabilities of the different scenarios and temperature changes is unachievable, the objective must be to find the probabilities that are the most consistent with what our state of knowledge and expert judgment are. Therefore, subjective information plays, and should play, a crucial role. A new methodology, based on the Principle of Maximum Entropy, is proposed for constructing probabilistic climate change scenarios when only partial information is available. The objective is to produce relevant information for decision-making according to different agents’ judgment and subjective beliefs. These estimates have desirable properties such as: they are the least biased estimate possible on the available information; maximize the uncertainty (entropy) subject to the partial information that is given; The maximum entropy distribution assigns a positive probability to every event that is not excluded by the given information; no possibility is ignored. The probabilities obtained in this manner are the best predictions possible with the state of knowledge and subjective information that is available. This methodology allows distinguishing between reckless and cautious positions regarding the climate change threat. 相似文献
159.
160.
Javier Rodríguez Zaurín Joanna Holt Clive N. Tadhunter Rosa M. González Delgado 《Astrophysics and Space Science》2009,324(2-4):225-229
We use long-slit spectra taken with the William Herschel Telescope on La Palma and high-resolution Hubble Space Telescope imaging to study the gas kinematic in the halo of the ultraluminous infrared/radio galaxy PKS1345+12 (z=0.122). Our long-slit spectra show line splitting at the locations of massive star clusters ( $10^{6}<M_{\mathrm{SSC}}^{\mathrm{YSP}}<10^{7}$ M⊙), indicating that they are moving at up to 450 km?s?1 with respect to the local ambient gas. Given their kinematics, it is plausible that these super star clusters have been formed either in fast-moving gas streams or tidal tails that are falling back into the nuclear regions as part of the merger process, or as a consequence of jet-induced star formation linked to the extended, diffuse radio emission detected in the halo of the galaxy. 相似文献