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991.
In developed nations a growing emphasis is being placed on the promotion of environmental behaviours amongst individuals, or ‘citizen-consumers’, as a means to reduce personal carbon emissions in the light of climate change. Within the UK, focus has tended towards the segmentation of consumers into ‘lifestyle groups’ and the subsequent development of so-called social marketing behaviour change strategies, promoted as a way to encourage environmental behaviours. In the context of travel and tourism research, this approach has been operationalised through the notion of ‘mobility styles’ as a way of understanding the motivations and barriers different groups of consumers face when making pro-environmental travel decisions. However, this paper argues that the issue of climate change presents a major challenge for those attempting to promote behavioural changes using a single ‘mobility styles’ approach because of the ways in which issues such as climate change transcends the spatial and motivational contexts for travel behaviours. Using data gathered as part of a UK-based project on sustainable travel, the paper will demonstrate the potential conflicts that emerge when exploring daily travel behaviour and travel for short-breaks and holidays using a single mobility styles approach. The paper will argue that the discord between daily and holiday travel raises important questions for adopting a single and asptatial mobility styles approach for promoting behaviour change. This in turn highlights the challenges faced by a wider community of both researchers and policy makers in the environmental social sciences who seek to use segmentation as the basis for understanding and promoting behavioural change. 相似文献
992.
Maria Fajer Jan Maciej Waga Mariusz Rzetala Artur Szymczyk Ma?gorzata Nita Robert Machowski Martyna A. Rzetala Marek Ruman 《Journal of Paleolimnology》2012,48(4):651-667
Jezioro Lake is the only natural lake in southern Poland outside mountainous areas to have existed continuously since the Pleistocene. The record of environmental change in the Late Vistulian (Weichselian) and Holocene is preserved in the deposits and landforms around the lake. This paper presents the results of paleogeographical and paleoecological research that emabled us to reconstruct the history of the Jezioro Lake. At the end of the Vistulian period, the outlet of the lake was blocked by a parabolic dune moving in from the west. Limnic sedimentation was evident in the sediment core at all levels from the Holocene, with remains of Cladocera, Chironomidae larvae, and aquatic plants. The lake did not disappear at that time, although its area decreased by a factor of 12 by the end of the period. Paleobotanical research permitted the reconstruction of sequences of plant communities and changes in nutrient status and water level. An initial oligotrophic lake, as indicated by the presence of Iso?tes lacustris L., changed to a eutrophic lake, as indicated by the presence of Potamogeton natans L. and Nuphar sp., then the lake progressed to the present-day dystrophic lake that is surrounded by a swamp. The profile of organic deposits contains a record of environmental change at least since the Younger Dryas in southern Poland. 相似文献
993.
Limitations of single-basket trading: lessons from the Montreal Protocol for climate policy 总被引:1,自引:1,他引:0
John S. Daniel Susan Solomon Todd J. Sanford Mack McFarland Jan S. Fuglestvedt Pierre Friedlingstein 《Climatic change》2012,111(2):241-248
Numerous policy options exist to reduce future greenhouse gas emissions. A single-basket approach, which controls aggregate
emissions, was adopted by the Kyoto Protocol. Such an approach allows emissions reductions of one gas to be traded with those
of other gases in the “basket”, with the trade “price” determined by some weighting metric like the Global Warming Potential.
To reduce stratospheric ozone depletion, the Montreal Protocol also dealt with controlling many compounds, but did so employing
an alternative, multi-basket scheme. Trading was allowed within each basket, but not among baskets. While the Montreal Protocol
has been highly successful using this approach, we show that if a single-basket approach had been adopted the short-term success
could have been at risk due to the non-unique relationship between controls and environmental impacts when using a single
basket. Using climate policy as an example, and without considering technological and economic constraints, we further show
that the magnitude of the ambiguities in impacts associated with a single-basket approach depends on the rapidity of the emission
phaseout. Fast phaseouts lead to less ambiguity than do slow ones. These results suggest that for each set of greenhouse gas
control policies considered, the benefit of additional flexibility associated with a single-basket approach should be weighed
against the associated increased uncertainties in the impacts to ascertain whether a single- or a multi-basket approach has
the greater chance of successfully mitigating climate change. 相似文献
994.
William Perrie Zhenxia Long Hayley Hung Amanda Cole Alexandra Steffen Ashu Dastoor Dorothy Durnford Jianmin Ma Jan W. Bottenheim Stoyka Netcheva Ralf Staebler James R. Drummond N. T. O’Neill 《Climatic change》2012,115(1):35-58
This paper summarizes the main elements of four IPY projects that examine the Arctic Atmosphere. All four projects focus on present conditions with a view to anticipating possible climate change. All four investigate the Arctic atmosphere, ocean, ice, and land interfacial surfaces. One project uses computer models to simulate the dynamics of the Arctic atmosphere, storms, and their interactions with the ocean and ice interface. Another project uses statistical methods to infer transports of pollutants as simulated in large-scale global atmospheric and oceanic models verifying results with available observations. A third project focuses on measurements of pollutants at the ice-ocean?Catmosphere interface, with reference to model estimates. The fourth project is concerned with multiple, high accuracy measurements at Eureka in the Canadian Archipelago. While these projects are distinctly different, led by different teams and interdisciplinary collaborators, with different technical approaches and methodologies, and differing objectives, they all strive to understand the processes of the Arctic atmosphere and climate, and to lay the basis for projections of future changes. Key findings include: ? Decreased sea ice leads to more intense storms, higher winds, reduced surface albedo, increased surface air temperature, and enhanced vertical mixing in the upper ocean. ? Arctic warming may affect toxic chemicals by remobilizing persistent organic pollutants and augmenting mercury deposition/retention in the environment. ? Changes in sea ice can dramatically change processes in and at the ice surface related to ozone, mercury and bromine oxide and related chemical/physical properties. ? Structure and properties of the Arctic atmospheric??troposphere to stratosphere??and tracking of transport of pollution and smoke plumes from mid-latitudes to the poles. 相似文献
995.
Ileana Bladé Brant Liebmann Didac Fortuny Geert Jan van Oldenborgh 《Climate Dynamics》2012,39(3-4):709-727
Climate models predict substantial summer precipitation reductions in Europe and the Mediterranean region in the twenty-first century, but the extent to which these models correctly represent the mechanisms of summertime precipitation in this region is uncertain. Here an analysis is conducted to compare the observed and simulated impacts of the dominant large-scale driver of summer rainfall variability in Europe and the Mediterranean, the summer North Atlantic Oscillation (SNAO). The SNAO is defined as the leading mode of July–August sea level pressure variability in the North Atlantic sector. Although the SNAO is weaker and confined to northern latitudes compared to its winter counterpart, with a southern lobe located over the UK, it significantly affects precipitation in the Mediterranean, particularly Italy and the Balkans (correlations of up to 0.6). During high SNAO summers, when strong anticyclonic conditions and suppressed precipitation prevail over the UK, the Mediterranean region instead is anomalously wet. This enhanced precipitation is related to the presence of a strong upper-level trough over the Balkans—part of a hemispheric pattern of anomalies that develops in association with the SNAO—that leads to mid-level cooling and increased potential instability. Neither this downstream extension nor the surface influence of the SNAO is captured in the two CMIP3 models examined (HadCM3 and GFDL-CM2.1), with weak or non-existent correlations between the SNAO and Mediterranean precipitation. Because these models also predict a strong upward SNAO trend in the future, the error in their representation of the SNAO surface signature impacts the projected precipitation trends. In particular, the attendant increase in precipitation that, based on observations, should occur in the Mediterranean and offset some of the non-SNAO related drying does not occur. Furthermore, the fact that neither the observed SNAO nor summer precipitation in Europe/Mediterranean region exhibits any significant trend so far (for either the full century or the recent half of the record) does not increase our confidence in these model projections. 相似文献
996.
Sebastiaan W. Rampen Stefan Schouten Ben Abbas Anna A.M. Noordeloos Jan A.J. Geenevasen 《Geochimica et cosmochimica acta》2009,73(2):377-492
Analysis of the sterol composition of more than 100 diatom cultures, representing all major marine diatom orders, indicates that this group of algae may be an important source for 4-desmethyl-23,24-dimethyl steroids in sediments and petroleum, as their precursors, i.e. 4-desmethyl-23,24-dimethyl sterols, were present in 22 of the cultures. The phylogenetic positions of diatom species that produce 4-desmethyl-23,24-dimethyl sterols show that, within the centric diatoms, only a specific group of diatoms is able to produce these sterols, while within the pennate diatoms, a phylogenetic relationship between 4-desmethyl-23,24-dimethyl sterol-producing diatoms is less apparent. Based on the phylogenetic relationship, it is suggested that diatoms inherited the ability of producing these sterols from a single common ancestor, which originated between 150 and 100 Ma ago. Co-injection of an authentic 23R,24R-dimethyl-5α-cholestane standard with extracts confirmed its presence in sediments. We also tentatively identified three other 4-desmethyl-23,24-dimethyl sterane isomers having different side-chain stereo-configurations and observed that some of the isomers co-elute with other steranes including 24-ethyl-5α-cholestane. 相似文献
997.
Jan Ku
era Jan Cempírek Zdenk Dolní
ek Philippe Muchez Walter Prochaska 《Journal of Geochemical Exploration》2009,103(2-3):69-79
Rare earth elements and yttrium geochemistry of dolomite from post-Variscan vein-type Zn–Pb–Cu mineralization was studied in the Nízký Jeseník and Upper Silesian Basins. Combined with crush–leach analyses of fluid inclusions, the study provided important information on fluid–rock interaction, physico-chemical and redox conditions during crystallization of the dolomite. The mineralization is hosted by Carboniferous siliciclastic rocks, representing Variscan flysch and molasse sedimentation. Dolomite samples contain highly variable contents of REE (between 18 and 295 ppm) and Y (between 17 and 95 ppm). REY patterns are divided into four different groups which differ in regional provenance, LREE vs. HREE enrichment/depletion and significance of Eu, Gd and Y anomalies. These patterns can be the result of 1) precipitation of dolomite from near neutral fluids with important concentrations of complexing ligands as a main factor for the REY partitioning, 2) interaction of migrating fluids with host or basement rocks, or, most probably, 3) a combination of both.Regarding the importance of complexing ligands, it is proposed that in all samples fluoride and chloride complexes prevailed over sulphate, bicarbonate and hydroxide complexes. Interaction of fluids with rocks was strongly affected by the fluid temperature. Dolomites which precipitated from fluids with homogenization temperature higher than 110 °C are mostly REY-enriched while fluids colder than 110 °C produced REY-depleted dolomite. The REY-enrichment may indicate higher effectiveness of leaching of REE-bearing minerals (probably monazite, allanite and biotite) at higher temperatures. The preferential loss of LREE can be caused by the recrystallization or remobilization of dolomite. Generally, an increase in salinity and contents of Cl and F in the fluids is mostly accompanied by a higher REY content in dolomite. Positive Eu anomalies and small negative Gd and Y anomalies are typical for most of the chondrite-normalized patterns. Positive EuCN anomalies in dolomites are most probably the result of an increase of Eh in the parent fluid. Distribution of Y is expected to be predominantly controlled by solution complexation. 相似文献
998.
Long-term groundwater monitoring has been carried in the model locality of the landslide area at Třebenice, situated in the
northern part of the Czech Republic in Cretaceous claystones to marlstones. Primarily, long-term fluctuation of the groundwater
and piezometric levels has been monitored. Monitoring of groundwater flow was carried out in selected wells also by the photometry
logging method using a dilution technique of a marked liquid. On the basis of these results, the pattern of the groundwater
flow through the landslide area was determined in lithologically homogeneous Cretaceous claystones to marlstones. Interpretation
of monitoring results indicated that water flows preferentially through the zone of near-surface loosening of the claystone
rock massif, in general parallel to the slope inclination between 8 and 10-m depth below ground level. This zone exhibits
a higher permeability given by 1–2 orders of hydraulic conductivity compared with overlying strata and underlying rock in
which this zone is closed. This verified pattern of groundwater flow has a significant effect on the stability of the sliding
slope and it is one of the main factors affecting the evolution of landslides on the slopes formed by these rocks. 相似文献
999.
The Arctic Coring Expedition (ACEX) proved to be one of the most transformational missions in almost 40 year of scientific ocean drilling. ACEX recovered the first Cenozoic sedimentary sequence from the Arctic Ocean and extended earlier piston core records from ≈1.5 Ma back to ≈56 Ma. The results have had a major impact in paleoceanography even though the recovered sediments represents only 29% of Cenozoic time. The missing time intervals were primarily the result of two unexpected hiatuses. This important Cenozoic paleoceanographic record was reconstructed from a total of 339 m sediments. The wide range of analyses conducted on the recovered material, along with studies that integrated regional tectonics and geophysical data, produced surprising results including high Arctic Ocean surface water temperatures and a hydrologically active climate during the Paleocene Eocene Thermal Maximum (PETM), the occurrence of a fresher water Arctic in the Eocene, ice-rafted debris as old as middle Eocene, a middle Eocene environment rife with organic carbon, and ventilation of the Arctic Ocean to the North Atlantic through the Fram Strait near the early-middle Miocene boundary. Taken together, these results have transformed our view of the Cenozoic Arctic Ocean and its role in the Earth climate system. 相似文献
1000.
Positive Relationship between Freshwater Inflow and Oyster Abundance in Galveston Bay,Texas 总被引:1,自引:0,他引:1
David Buzan Wen Lee Jan Culbertson Nathan Kuhn Lance Robinson 《Estuaries and Coasts》2009,32(1):206-212
Analysis of fisheries-independent data for Galveston Bay, Texas, USA, since 1985 shows eastern oysters (Crassostrea virginica) frequently demonstrate increased abundance of market-sized oysters 1 to 2 years after years with increased freshwater inflow
and decreased salinity. These analyses are compared to Turner’s (Estuaries and Coasts 29:345–352, 2006) study using 3-year running averages of oyster commercial harvest since 1950 in Galveston Bay. Turner’s results indicated
an inverse relationship between freshwater inflow and commercial harvest with low harvest during years of high inflow and
increased harvest during low flow years. Oyster populations may experience mass mortalities during extended periods of high
inflow when low salinities are sustained. Conversely, oyster populations may be decimated during prolonged episodes of low
flow when conditions favor oyster predators, parasites, and diseases with higher salinity optima. Turner’s (Estuaries and
Coasts 29:345–352, 2006) analysis was motivated by a proposed project in a basin with abundant freshwater where the goal of the project was to substantially
increase freshwater flow to the estuary in order to increase oyster harvest. We have the opposite concern that oysters will
be harmed by projects that reduce flow, increase salinity, and increase the duration of higher salinity periods in a basin
with increasing demand for limited freshwater. Turner’s study and our analysis reflect different aspects of the complex, important
relationships between freshwater inflow, salinity, and oysters. 相似文献