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991.
Over the past decade, scientists and journalists have prominently utilized the metaphor of a tipping point for drastic, irreversible and dangerous climate change. This paper shows how the tipping point metaphor became a multi-purpose bridge between science and the news media, describing how its meaning and use developed and diversified in interaction between these two domains. Within the scientific domain, the metaphor developed from a rhetorical device conveying a warning of drastic, irreversible and dangerous climate change to a theoretical concept driving empirical research. The news media soon picked up the tipping point metaphor for abrupt and dangerous climate change, turning it into a common part of the journalistic lexicon. Moreover, both science and the news media developed another, societal use of the tipping point metaphor, calling for radical societal change to avoid climate change catastrophe. The tipping point metaphor is hence not a monolithic notion but a highly versatile concept and expression, allowing it to be used for various communicative purposes by distinct stakeholders in different contexts.  相似文献   
992.
Some extreme weather events may be more likely to affect climate change beliefs than others, in part because schema individuals possess for different events could vary in encouraging such links. Using a representative sample of U.S. adults and geocoded National Weather Service data, we examine how a range of extreme weather event categories relate to climate change beliefs, and the degree to which individuals’ self-reported experiences are shaped by their political views across event types. For tornado, hurricane, and flood events, we find no link with beliefs. For polar vortex and drought events, we find that although self-reported experience is linked with climate beliefs, reporting of these experiences is influenced by political identity and partisan news exposure. These findings underscore a limited role for extreme weather experiences in climate beliefs, and show that events more open to interpretation, such as droughts and polar vortex disturbances, are most likely to be seen through a partisan lens.  相似文献   
993.
The article explores the new media’s role in climate change communication in Russia. By providing an open space for the expression of very diverse points of view, the internet creates a substitute media reality where both climate activists and climate sceptics can question the established discourse. Analysis of 374 entries published on the LiveJournal blogging platform has resulted in the identification of four discursive categories: “conspiracies of climate change,” “climate change impact,” “political games of climate change” and “online (anti-)environmentalism.” Each category demonstrates how the same topic can be framed in very different ways depending on bloggers’ worldview rather than the nature of the discussed environmental problem. The findings also show that the blogs act as “echo-chambers” for both climate deniers and climate activists reinforcing their behold beliefs. Finally, the analysis discovers some parallels with the traditional media coverage in their minimal critique of Russian state policy on climate.  相似文献   
994.
Two means by which climate change may increase surface soil erosion in mountainous terrain are: (1) increasing the frequency of extreme rainfall events and (2) decreasing the duration of snow cover on bare soil. We used output from four general circulation models (GCMs) and two greenhouse gas trajectories to produce a suite of hydrologic variables at a daily time‐step for historic and projected 21st Century conditions. We statistically disaggregated the daily rainfall to hourly, using hourly rainfall from a network of nine weather stations in the Tahoe Basin, and filtered out rain falling on a snowpack. We applied published equations to convert hourly intensity to raindrop kinetic energy (KE) for each day and grid cell in the Basin, averaged across grid cells, and created time series of total annual and maximum annual hourly kinetic energy (TKE and MKE) on snow‐free ground. Using the Generalized Extreme Value distribution, we calculated the significance of long‐term trends in KE on snow‐free ground, and estimated energy levels for return periods of 2, 20, and 100 years. We then detrended the snowpack data and compared the resulting trends in KE with the trends resulting from changes in both rainfall energy and snowpack under two GCMs. Principal findings include (1) upward trends in MKE, (2) stronger upward trends in TKE; and (3) an effect of increasing rainfall intensities on KE in some cases, and a strong effect of reduced snowpack in all cases examined.  相似文献   
995.
In glacierized catchments, elevation is correlated with meltwater through its association with temperature, precipitation, and glacier hypsometry. The revelation of the altitudinal distribution of meltwater, unattended and not fully understood in previous work, might provide a better understanding of climate change impacts on glacio‐hydrology. Here, critical zone approach was defined and applied in 12 glacierized catchments of the Tien Shan–Pamir–Karakorum Mountains, Central Asia using manually calibrated glacier‐enhanced Soil and Water Assessment Tool model over 1966–2005. The critical zone, a sequence of elevation bands with above‐average snow and glacier melt, contributes maximum meltwater to total runoff. The critical zone shared 37%–95% (average = 80%) of meltwater contributions to total runoff, although its size was only 13%–30% of the total elevational relief. The critical zone controlled 76% and 82% variability in relative changes of glacier area and total runoff at the catchment scale, respectively. The increase in temperature was identified as the dominant driver for variations in total runoff in all catchments except Vakhsh and Yurungkash, where precipitation change remained dominant. Overall, glacier hypsometry limited the first‐order control of meltwater distributions on glacio‐hydrology. It is concluded that critical zone approach can interpret the proxy role of elevation to affect water availability under climate and glacier area change in glacierized catchments.  相似文献   
996.
Changing climate and land cover are expected to impact flood hydrology in the Delaware River Basin over the 21st Century. HEC‐HMS models (U.S. Army Corps of Engineers Hydrologic Engineering Center‐Hydrologic Modeling System) were developed for five case study watersheds selected to represent a range of scale, soil types, climate, and land cover. Model results indicate that climate change alone could affect peak flood discharges by ?6% to +58% a wide range that reflects regional variation in projected rainfall and snowmelt and local watershed conditions. Land cover changes could increase peak flood discharges up to 10% in four of the five watersheds. In those watersheds, the combination of climate and land cover change increase modeled peak flood discharges by up to 66% and runoff volumes by up to 44%. Precipitation projections are a key source of uncertainty, but there is a high likelihood of greater precipitation falling on a more urbanized landscape that produces larger floods. The influence of climate and land cover changes on flood hydrology for the modeled watersheds varies according to future time period, climate scenario, watershed land cover and soil conditions, and flood frequency. The impacts of climate change alone are typically greater than land cover change but there is substantial geographic variation, with urbanization the greater influence on some small, developing watersheds.  相似文献   
997.
Assessing groundwater resources in the arid and semiarid borderlands of the United States and Mexico represents a challenge for land and water managers, particularly in the Transboundary Santa Cruz Aquifer (TSCA). Population growth, residential construction, and industrial activities have increased groundwater demand in the TSCA, in addition to wastewater treatment and sanitation demands. These activities, coupled with climate variability, influence the hydrology of the TSCA and emphasize the need for groundwater assessment tools for decision‐making purposes. This study assesses the impacts of changes in groundwater demand, effluent discharge, and climate uncertainties within the TSCA from downstream of the Nogales International Wastewater Treatment Plant to the northern boundary of the Santa Cruz Active Management Area. We use a conceptual water budget model to analyze the long‐term impact of the different components of potential recharge and water losses within the aquifer. Modeling results project a future that ranges from severe long‐term drying to positive wetting. This research improves the understanding of the impact of natural and anthropogenic variables on water sustainability, with an accessible methodology that can be globally applied.  相似文献   
998.
We introduced a multilevel model of value shift to describe the changing social context of wildlife conservation. Our model depicts how cultural-level processes driven by modernization (e.g., increased wealth, education, and urbanization) affect changes in individual-level cognition that prompt a shift from domination to mutualism wildlife values. Domination values promote beliefs that wildlife should be used primarily to benefit humans, whereas mutualism values adopt a view that wildlife are part of one's social network and worthy of care and compassion. Such shifts create emergent effects (e.g., new interest groups) and challenges to wildlife management organizations (e.g., increased conflict) and dramatically alter the sociopolitical context of conservation decisions. Although this model is likely applicable to many modernized countries, we tested it with data from a 2017–2018 nationwide survey (mail and email panel) of 43,949 residents in the United States. We conducted hierarchical linear modeling and correlational analysis to examine relationships. Modernization variables had strong state-level effects on domination and mutualism. Higher levels of education, income, and urbanization were associated with higher percentages of mutualists and lower percentages of traditionalists, who have strong domination values. Values affected attitudes toward wildlife management challenges; for example, states with higher proportions of mutualists were less supportive of lethal control of wolves (Canis lupus) and had lower percentages of active hunters, who represent the traditional clientele of state wildlife agencies in the United States. We contend that agencies will need to embrace new strategies to engage and represent a growing segment of the public with mutualism values. Our model merits testing for application in other countries.  相似文献   
999.
Small-scale fisheries are an important livelihood and primary protein source for coastal communities in many of the poorest regions in the world, yet many are overfished and thus require effective and scalable management solutions. Positive ecological and socioeconomic responses to management typically lag behind immediate costs borne by fishers from fishing pressure reductions necessary for fisheries recovery. These short-term costs challenge the long-term success of these interventions. However, social marketing may increase perceptions of management benefits before ecological and socioeconomic benefits are fully realized, driving new social norms and ultimately long-term sustainable behavior change. By conducting underwater visual surveys to quantify ecological conditions and by conducting household surveys with community members to quantify their perceptions of management support and socioeconomic conditions, we assessed the impact of a standardized small-scale fisheries management intervention that was implemented across 41 sites in Brazil, Indonesia, and the Philippines. The intervention combines TURF reserves (community-based territorial use rights for fishing coupled with no-take marine reserves) with locally tailored social-marketing behavior change campaigns. Leveraging data across 22 indicators and 4 survey types, along with data from 3 control sites, we found that ecological and socioeconomic impacts varied and that communities supported the intervention and were already changing their fishing practices. These results suggest that communities were developing new social norms and fishing more sustainably before long-term ecological and socioeconomic benefits of fisheries management materialized.  相似文献   
1000.
The ecological impacts of extreme climatic events on population dynamics and community composition are profound and predominantly negative. Using extensive data of an ecological model system, we tested whether predictions from ecological models remain robust when environmental conditions are outside the bounds of observation. We observed a 10-fold demographic decline of the Glanville fritillary butterfly (Melitaea cinxia) metapopulation on the Åland islands, Finland in the summer of 2018 and used climatic and satellite data to demonstrate that this year was an anomaly with low climatic water balance values and low vegetation productivity indices across Åland. Population growth rates were strongly associated with spatiotemporal variation in climatic water balance. Covariates shown previously to affect the extinction probability of local populations in this metapopulation were less informative when populations were exposed to severe drought during the summer months. Our results highlight the unpredictable responses of natural populations to extreme climatic events.  相似文献   
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