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981.
Climate change presents a threat to the sustainability of cities and their societies, and must be adequately addressed. Urban environments (cities) are responsible for the creation of a significant amount of greenhouse gas emissions which are the source of climate change. Cities have been increasingly the focus of action to address climate change, yet emissions are not significantly reducing. Additionally, there a lack of integration between adaptation and mitigation. This prevents responses adequate to limit global warming to 1.5OC, and to be well adapted to anticipated changes. This paper critically analyses existing definitions and typologies of climate change actions. A definition of ‘climate change transformation’ is proposed which includes the integration of adaptation and mitigation goals to enable a new regime in which global warming is limited to 1.5OC. A new three-part typology: ‘coping, malaction and transformation,’ is presented for categorising climate change actions by the extent to which they integrate adaptation and mitigation, and define a new regime. The typology is accompanied by illustrations to demonstrate the relationship between adaptation and mitigation. The definition, typology and illustration serve to guide effective climate change decision making, and provides principles to guide application in urban environments. 相似文献
982.
João Moreno Francisco Fatela Eduardo Leorri José M. De la Rosa Inês Pereira M. Fátima Araújo M. Conceição Freitas D. Reide Corbett Ana Medeiros 《Quaternary Research》2014
A high-resolution study of a marsh sedimentary sequence from the Minho estuary provides a new palaeoenvironmental reconstruction from NW Iberian based on geological proxies supported by historical and instrumental climatic records. A low-salinity tidal flat, dominated by Trochamminita salsa, Haplophragmoides spp. and Cribrostomoides spp., prevailed from AD 140–1360 (Roman Warm Period, Dark Ages, Medieval Climatic Anomaly). This sheltered environment was affected by high hydrodynamic episodes, marked by the increase in silt/clay ratio, decrease of organic matter, and poor and weakly preserved foraminiferal assemblages, suggesting enhanced river runoff. The establishment of low marsh began at AD 1380. This low-salinity environment, marked by colder and wet conditions, persisted from AD 1410–1770 (Little Ice Age), when foraminiferal density increased significantly. Haplophragmoides manilaensis and Trochamminita salsa mark the transition from low to high marsh at AD 1730. Since AD 1780 the abundances of salt marsh species (Jadammina macrescens, Trochammina inflata) increased, accompanied by a decrease in foraminiferal density, reflecting climate instability, when droughts alternate with severe floods. SW Europe marsh foraminifera respond to the hydrological balance, controlled by climatic variability modes (e.g., NAO) and solar activity, thus contributing to the understanding of NE Atlantic climate dynamics. 相似文献
983.
984.
《Geoforum》2014
Adaptation to climate change is widely recognized as a multi-level governance challenge because expected impacts and respective measures cut across governmental levels, sectors and societal domains. The present paper analyses the role of regional adaptation partnerships in Canada and England in the multi-level governance of climate change adaptation. We describe and compare three partnerships per country with regard to their evolution, membership and governing structures, coordination across levels and societal domains, and their adaptation activities and outputs. Although both partnership schemes represent new collaborative approaches, their genesis and governance differ. While the Canadian collaboratives are a government-centred approach that originated and partly operated top-down through a national programme for the period 2009–2012, the English partnerships follow a more pluralistic stakeholder-centred approach that evolved bottom-up already in the early 2000s. Both schemes have in common that they mediate between governmental levels, foster networking between public and private actors, and eventually build adaptive capacities and inform adaptation policies. We conclude that regional adaptation partnerships represent a new governance approach that facilitates climate change adaptation, albeit with limits. Since state actors play(ed) key roles in both partnership schemes, they do not represent a new sphere of authority outside the state. Instead of blurring or destabilizing governmental levels they complement (and perhaps even stabilise) them with multi-level interactions. 相似文献
985.
Small mammal communities in western North America experienced declines in taxonomic richness across the late Pleistocene to Holocene transition (PHT), a recent natural global warming event. One community also experienced a decline in evenness and others replaced one species with a congener. Variability in response of small mammal communities to PHT warming is apparent. At the presently arid and xeric Marmes site in the Columbia Basin of southeastern Washington State, megafauna were absent by about 13,000 cal yr BP, evenness of small mammals declined about 11,700 cal yr BP and again about 11,400 cal yr BP whereas richness declined about 11,400 cal BP. Regional faunal turnover was, however, minimal among small-bodied taxa. Local mammal communities are depauperate as a result of megafaunal extinctions and subsequent decreases in small-mammal richness and evenness. The latter chronologically corresponds with a decrease in primary productivity driven by increasing warmth and aridity. More faunas must be studied in order to fully document the range of variability in the responses of mammalian communities to PHT warming. Documentation of patterns in those responses will facilitate understanding and enhance predictive accuracy with respect to responses of mammalian communities to modern global warming. 相似文献
986.
Trace-element variations in an annually layered stalagmite as recorders of climatic changes and anthropogenic pollution in Central China 总被引:1,自引:0,他引:1
We analyzed variations in the Sr/Ca, Ba/Ca, REE/Ca (REE: rare earth element), Zn/Ca, and Pb/Ca ratios preserved in an annually layered stalagmite, XL21, from central China. The stalagmite record spans the 95 year period AD 1914–2008. The Sr/Ca and Ba/Ca ratios have a significant positive correlation with the stalagmite's growth rate, suggesting that they were primarily controlled by growth-rate variations. Variations in REE/Ca ratios are consistent with local temperature changes, suggesting temperature influenced REE concentrations in the stalagmite over decadal to annual timescales. Higher temperature in this humid area can increase vegetation cover, microbial activity, and organic decomposition in the soil, resulting in enhanced pCO2, organic matter concentration and reduced pH, and consequently increased REE mobilization from the overlying soil layer and host rock. Higher temperatures may also increase the natural Zn mobilization from the overlying soil mediated by organic matter and consequently may have led to increased Zn retention in XL21. An increasing trend is seen in the Pb/Ca ratios from XL21 since 1985, which is consistent with increased lead production in this area, and indicates an increase in mine-derived lead pollution in the local environment over the past 30 years. 相似文献
987.
We reconstructed vegetation responses to climate oscillations, fire and human activities since the last glacial maximum in inland NW Iberia, where previous paleoecological research is scarce. Extremely sparse and open vegetation composed of steppic grasslands and heathlands with scattered pioneer trees suggests very cold and dry conditions during the Oldest Dryas, unsuitable for tree survival in the surroundings of the study site. Slight woodland expansion during the Bølling/Allerød was interrupted by the Younger Dryas cooling. Pinewoods dominated for most of the early Holocene, when a marked increase in fire activity occurred. Deciduous trees expanded later reaching their maximum representation during the mid-Holocene. Enhanced fire activity and the presence of coprophilous fungi around 6400–6000 cal yr BP suggest an early human occupation around the site. However, extensive deforestation only started at 4500 cal yr BP, when fire was used to clear the tree canopy. Final replacement of woodlands with heathlands, grasslands and cereal crops occurred from 2700 cal yr BP onwards due to land-use intensification. Our paleoecological record can help efforts aimed at restoring the natural vegetation by indicating which communities were dominant at the onset of heavy human impact, thus promoting the recovery of currently rare oak and alder stands. 相似文献
988.
989.
Abstract One and a half decades of climate negotiations have directly caused greenhouse gas emissions of about 150,000 t CO2. At prevailing market prices, making the full negotiation process greenhouse-gas-neutral ex post would cost about US$0.5 million, which is a fraction of the cost of the conferences. 相似文献
990.
Bridging the gap: empowering decision-making for adaptation through the UK Climate Impacts Programme
Abstract The methods, tools and outputs of the UK Climate Impacts Programme (UKCIP) show how building adaptive capacity to climate change can be embedded within a wide range of organizations. UKCIP has been operating since 1997 to support decision-makers' assessments of their vulnerability to climate change so that they can plan how to adapt. Whilst stakeholder engagement is now generally regarded as vital to ensure that research meets the needs of decision-makers for information, this usually means that stakeholders are positioned in a ‘consultative’ role in research. In contrast, the UKCIP aims to bridge the gap between research and policy so that decision-makers take control to produce research in ways that are useful to them. The Programme has been flexible and was developed incrementally, with increased scientific understanding, taking advantage of collaborative funding and facilitating long-standing partnerships. Whilst the core framework of scenarios and tools has been developed centrally, most studies have been stakeholder-funded and led. The Programme's results suggest that if decision-makers are supported, capacity is built for assessments, and crucially, research outputs are directly applicable to their ongoing work and strategic planning. This capacity-building has worked across scales and sectors and is an effective route to mainstreaming climate change adaptation. The implication, therefore, is that more support should be given by funding agencies to develop institutional capacity to support adaptation to climate change in both the private and public sectors. 相似文献