908 resultados para Hydrology and Climate Change II


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Leishmaniasis is one of the most important emerging vector-borne diseases in Western Eurasia. Although winter minimum temperatures limit the present geographical distribution of the vector Phlebotomus species, the heat island effect of the cities and the anthropogenic heat emission together may provide the appropriate environment for the overwintering of sand flies. We studied the climate tempering effect of thermal bridges and the heat island effect in Budapest, Hungary. Thermal imaging was used to measure the heat surplus of heat bridges. The winter heat island effect of the city was evaluated by numerical analysis of the measurements of the Aqua sensor of satellite Terra. We found that the surface temperature of thermal bridges can be at least 3-7 °C higher than the surrounding environment. The heat emission of thermal bridges and the urban heat island effect together can cause at least 10 °C higher minimum ambient temperature in winter nights than the minimum temperature of the peri-urban areas. This milder micro-climate of the built environment can enable the potential overwintering of some important European Phlebotomus species. The anthropogenic heat emission of big cities may explain the observed isolated northward populations of Phlebotomus ariasi in Paris and Phlebotomus neglectus in the agglomeration of Budapest.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Aims: In the Mediterranean areas of Europe, leishmanisasis is one of the most emerging vector-borne diseases. Members of genus Phlebotomus are the primary vectors of the genus Leishmania. To track the human health effect of climate change it is a very important interdisciplinary question to study whether the climatic requirements and geographical distribution of the vectors of human pathogen organisms correlate with each other. Our study intended to explore the potential effects of ongoing climate change, in particular through a potential upward altitudinal and latitudinal shift of the distribution of the parasite Leishmania infantum, its vectors Phlebotomus ariasi, P. neglectus, P. perfiliewi, P. perniciosus, and P. tobbi, and some other sandfly species: P. papatasi, P. sergenti, and P. similis. Methods: By using a climate envelope modelling (CEM) method we modelled the current and future (2011-2070) potential distribution of 8 European sandfly species and L. infantum based on the current distribution using the REMO regional climate model. Results: We found that by the end of the 2060’s most parts of Western Europe can be colonized by sandfly species, mostly by P. ariasi and P. pernicosus. P. ariasi showed the greatest potential northward expansion. For all the studied vectors of L. infantum the entire Mediterranean Basin and South-Eastern Europe seemed to be suitable. L. infantum can affect the Eastern Mediterranean, without notable northward expansion. Our model resulted 1 to 2 months prolongation of the potentially active period of P. neglectus P. papatasi and P. perniciosus for the 2060’s in Southern Hungary. Conclusion: Our findings confirm the concerns that leishmanisais can become a real hazard for the major part of the European population to the end of the 21th century and the Carpathian Basin is a particularly vulnerable area.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Climate warming is predicted to cause an increase in the growing season by as much as 30% for regions of the arctic tundra. This will have a significant effect on the physiological activity of the vascular plant species and the ecosystem as a whole. The need to understand the possible physiological change within this ecosystem is confounded by the fact that research in this extreme environment has been limited to periods when conditions are most favorable, mid June–mid August. This study attempted to develop the most comprehensive understanding to date of the physiological activity of seven tundra plant species in the Alaskan Arctic under natural and lengthened growing season conditions. Four interrelated lines of research, scaling from cellular signals to ecosystem processes, set the foundation for this study. ^ I established an experiment looking at the physiological response of arctic sedges to soil temperature stress with emphasis on the role of the hormone abscisic acid (ABA). A manipulation was also developed where the growing season was lengthened and soils were warmed in an attempt to determine the maximum physiological capacity of these seven vascular species. Additionally, the physiological capacities of four evergreens were tested in the subnivean environment along with the potential role anthocyanins play in their activity. The measurements were scaled up to determine the physiological role of these evergreens in maintaining ecosystem carbon fluxes. ^ These studies determined that soil temperature differentials significantly affect vascular plant physiology. ABA appears to be a physiological modifier that limits stomatal processes when root temperatures are low. Photosynthetic capacity was limited by internal plant physiological mechanisms in the face of a lengthened growing season. Therefore shifts in ecosystem carbon dynamics are driven by changes in species composition and biomass production on a per/unit area basis. These studies also found that changes in soil temperatures will have a greater effect of physiological processes than would the same magnitude of change in air temperature. The subnivean environment exhibits conditions that are favorable for photosynthetic activity in evergreen species. These measurements when scaled to the ecosystem have a significant role in limiting the system's carbon source capacity. ^

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Climate change is one of the most important and urgent issues of our time. Since 2006, China has overtaken the United States as the world’s largest greenhouse gas (GHG) emitter. China’s role in an international climate change solution has gained increased attention. Although much literature has addressed the functioning, performance, and implications of existing climate change mitigation policies and actions in China, there is insufficient literature that illuminates how the national climate change mitigation policies have been formulated and shaped. This research utilizes the policy network approach to explore China’s climate change mitigation policy making by examining how a variety of government, business, and civil society actors have formed networks to address environmental contexts and influence the policy outcomes and changes. The study is qualitative in nature. Three cases are selected to illustrate structural and interactive features of the specific policy network settings in shaping different policy arrangements and influencing the outcomes in the Chinese context. The three cases include the regulatory evolution of China’s climate change policy making; the country’s involvement in the Clean Development Mechanism (CDM) activity, and China’s exploration of voluntary agreement through adopting the Top-1000 Industrial Energy Conservation Program. The historical analysis of the policy process uses both primary data from interviews and fieldwork, and secondary data from relevant literature. The study finds that the Chinese central government dominates domestic climate change policy making; however, expanded action networks that involve actors at all levels have emerged in correspondence to diverse climate mitigation policy arrangements. The improved openness and accessibility of climate change policy network have contributed to its proactive engagement in promoting mitigation outcomes. In conclusion, the research suggests that the policy network approach provides a useful tool for studying China’s climate change policy making process. The involvement of various types of state and non-state actors has shaped new relations and affected the policy outcomes and changes. In addition, through the cross-case analysis, the study challenges the “fragmented authoritarianism” model and argues that this once-influential model is not appropriate in explaining new development and changes of policy making processes in contemporary China.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Climate change has been a security issue for mankind since Homo sapiens first emerged on the planet, driving him to find new and better food, water, shelter, and basic resources for survival and the advancement of civilization. Only recently, however, has the rate of climate change coupled with man’s knowledge of his own role in that change accelerated, perhaps profoundly, changing the security paradigm. If we take a ―decades‖ look at the security issue, we see competition for natural resources giving way to Cold War ideological containment and deterrence, itself giving way to non-state terrorism and extremism. While we continue to defend against these threats, we are faced with even greater security challenges that inextricably tie economic, food and human security together and where the flash points may not provide clearly discernable causes, as they will be intrinsically tied to climate change. Several scientific reports have revealed that the modest development gains that can be realized by some regions could be reversed by climate change. This means that climate change is not just a long-term environmental threat as was widely believed, but an economic and developmental disaster that is unfolding. As such, addressing climate change has become central to the development and poverty reduction by the World Bank and other financial institutions. In Latin America, poorer countries and communities, such as those found in Central America, will suffer the hardest because of weaker resilience and greater reliance on climatesensitive sectors such as agriculture. The US should attempt to deliver capability to assist these states to deal with the effects of climate change.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Climate change is estimated to be responsible for 400,000 deaths per year, mostly because of hunger and communicable diseases affecting children in the Global South. Using the sociology of W.E.B. Du Bois, I attempt to demonstrate how and why climate change occurs along the color line. I conclude by arguing why it is important to think about climate change as a human rights issue.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

While there is considerable literature on neoliberalism in and of nature and the environment as well as in the interface between climate change and globalization, attempts at marrying the various conceptualizations of these have been limited. In this paper, I briefly review a portion of the literature on climate change and globalization (both broadly defined) locating the connections and disconnections on the topic. I then attempt to synthesize some of the ideas and problems expressed in many of these existing approaches to develop a Deleuzoguattarian approach to the intersections of climate change and globalization across spaces and scales. Finally, I argue that a non-linear historical materialism provides a way of addressing the limitations in existing frameworks.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Climate change in the Arctic is predicted to increase plant productivity through decomposition-related enhanced nutrient availability. However, the extent of the increase will depend on whether the increased nutrient availability can be sustained. To address this uncertainty, I assessed the response of plant tissue nutrients, litter decomposition rates, and soil nutrient availability to experimental climate warming manipulations, extended growing season and soil warming, over a 7 year period. Overall, the most consistent effect was the year-to-year variability in measured parameters, probably a result of large differences in weather and time of snowmelt. The results of this study emphasize that although plants of arctic environments are specifically adapted to low nutrient availability, they also posses a suite of traits that help to reduce nutrient losses such as slow growth, low tissue concentrations, and low tissue turnover that result in subtle responses to environmental changes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Dyer, along with many others reflecting international consensus in the scientific community, argues that countries must be carbon neutral by 2050 to avoid the worst impacts of climate change (Dyer, 2008, p. xii). to accomplish this by 2050, we need to act now: governments need to cooperate with the scientific community to ensure our society makes the changes to combat climate change. How is Canada reacting to this situation? As describes by the Sierra Club of Canada, "federal government continues to drag its feet, and delay any action to reduce emissions" (2008, p. 18). Given this federal reluctance, individual provinces must act to reduce emissions. While some provinces take a required action, primarily Quebec and British Columbia, others, like Newfoundland and Labrador, contribute little in terms of emissions reductions. Newfoundland and Labrador is ranked as "poor"-among the worst performers regarding climate change policy in the country-by the David Suzuki Foundation in a cross Canada evaluation of various provincial climate change policies (David Suzuki Foundation, 2008, p. 9). The Province of Newfoundland is not doing enough to address climate change. In this paper I argue that to improve this situation, the province could follow the example of the two leading jurisdictions, Quebec and British Columbia, to refine and introduce its own hybrid policy that directly affects decision making processes. But, this can be complicated when convincing the government that it is important to accept stronger policy. The government must consider what climate change impacts Newfoundland and Labrador experiences and willconinue to experience and what Newfoundland and Labrador is contributing to the problem of climate change. To evaluate these issues of climate change, I first survey the positive policies Newfoundland and Labrador is currently implementing/ discussing and then outline action taken by the provincial environment leaders, Quebec and British Columbia.Then I describe the strong pieces in the Quebec and British Columbia climate change action plan that Newfoundland and Labrador can emulate. Finally, I consider if thes polices are politically feasible for the government of Newfoundland and labrador. Hence, this paper aims to give a blueprint of what Newfoundland and Labrador has to act on to make itself an environmental leader.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

28 pages, 6 figures; version submitted to Proceedings of the National Academy of Sciences

Relevância:

100.00% 100.00%

Publicador:

Resumo:

28 pages, 6 figures; version submitted to Proceedings of the National Academy of Sciences

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Acknowledgements This work was funded by the projects HAR2013-43701-P (Spanish Economy and Competitiveness Ministry) and CGL2010-20672 (Spanish Ministry of Science and Innovation). This research was also partially developed with Xunta de Galicia funding (grants R2014/001 and GPC2014/009). N. Silva-Sánchez is currently supported by a FPU pre-doctoral grant (AP2010-3264) funded by the Spanish Government. We are grateful to Ana Moreno, Mariano Barriendos and Gerardo Benito who kindly provide us data included in Figure 5a. We also want to thank constructive comments from two anonymous reviewers.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Acknowledgements This work was funded by the projects HAR2013-43701-P (Spanish Economy and Competitiveness Ministry) and CGL2010-20672 (Spanish Ministry of Science and Innovation). This research was also partially developed with Xunta de Galicia funding (grants R2014/001 and GPC2014/009). N. Silva-Sánchez is currently supported by a FPU pre-doctoral grant (AP2010-3264) funded by the Spanish Government. We are grateful to Ana Moreno, Mariano Barriendos and Gerardo Benito who kindly provide us data included in Figure 5a. We also want to thank constructive comments from two anonymous reviewers.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Across North America, grassland songbirds have undergone steep population declines over recent decades, commonly attributed to agricultural intensification. Understanding the potential interactions between the impacts of climate change on the future distributions of these species and the availability of suitable vegetation for nesting can support improved risk assessments and conservation planning for this group of species. We used North American bioclimatic niche models to examine future changes in suitable breeding climate for 15 grassland songbird species at their current northern range limits along the boreal forest–prairie ecotone in Alberta, Canada. Our climate suitability projections, combined with the current distribution of native and tame pasture and cropland in Alberta, suggest that some climate-mediated range expansion of grassland songbirds in Alberta is possible. For six of the eight species projected to experience expansions of suitable climate area in Alberta, this suitable climate partly overlaps the current distribution of suitable land cover. Additionally, for more than half of the species examined, most of the area of currently suitable climate was projected to remain suitable to the end of the century, highlighting the importance of Alberta for the long-term persistence of these species. Some northern prairie-endemic species exhibited substantial projected northward shifts of both the northern and southern edges of the area of suitable climate. Baird’s Sparrow (Ammodramus bairdii) and Sprague’s Pipit (Anthus spragueii), both at-risk grassland specialists, are predicted to have limited climate stability within their current ranges, and their expansion into new areas of suitable climate may be limited by the availability of suitable land cover. Our results highlight the importance of the preservation and restoration of remaining suitable grassland habitat within areas of projected climate stability and beyond current northern range limits for the long-term persistence of many grassland songbird species in the face of climate change.