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1.
The simulation of Sea-ice in a coarse resolution ocean general circulation model is examined in Hudson Bay and surrounding waters. Sea-ice distribution and duration compared well to climatological values, although ice thickness is undersimulated as it is in other modelling work. In Hudson Bay ice thickness variation was dominated by the atmospheric forcing as shown by the symmetric response of ice thickness to warming and cooling scenarios. Below ice heat fluxes play a more significant role in Foxe Basin and Baffin Bay where they mitigate air-ice heat loss by as much as 40 percent, thus limiting ice thickness and duration. Below ice heat flux reduces by 23 percent for the region of study (Hudson Bay, Foxe Basin, Baffin Bay, and Labrador Sea) for a global 3°C cooling and increases by 9 percent for a 3°C global warming. This asymmetric response is attributed to the ocean's asymmetric response to warming and cooling scenarios. In so much as Hudson Bay is dominated by atmospheric forcing rather than under ice heat as these results indicate, coarse resolution models may be useful in assessing the impact of change. However the necessary reconfiguration of the model grid render results from Foxe Basin and Hudson Strait less credible. On étudie la simulation de glace marine dans un modèle de circulation océanique générale à faible résolution dans la baie d'Hudson et dans les eaux avoisinantes. La distribution et la durée de la glace marine correspondent bien aux valeurs climatologiques, bien que l'épaisseur de la glace soit sous-simulée comme c'est le cas dans d'autres travaux de modélisation. Dans la baie d'Hudson, la variation de l'epaisseur de la glace est dominée par le forçage atmosphérique, comme on peut le voir d'après la réponse symétrique de l'épaisseur de la glace suivant les scénarios de réchauffement et de refroidissement. Les flux de chaleur sous la glace jouent un rôle plus important dans le bassin de Foxe et la baie Baffin, où ils permettent une réduction des pertes de chaleur air-glace allant jusqu'à 40 pour cent, limitant ainsi l'épaisseur de la glace et la durée. Le flux de chaleur sous la glace diminue de 23 pour cent dans la région étudiée (baie d'Hudson, bassin de Foxe, baie Baffin et mer du Labrador) pour un refroidissement global de 3C et augmente de 9 pour cent pour un réchauffement global de 3C. On attribue cette réponse asymétrique à la réponse asymétrique de l'océan aux scénarios de refroidissement et de réchauffement. Dans la mesure où, comme l'indiquent ces résultats, la baie d'Hudson est dominée par le forçage atmosphérique plutôt que par la chaleur sous la glace, des modèles à faible résolution peuvent être utiles pour évaluer l'impact des changements. Cependant, la reconfiguration nécessaire de la grille du modèle atténue la crédibilité des résultats obtenus dans le Bassin de Foxe et le détroit d'Hudson. 相似文献
2.
The excavation in the 1890s of a skeleton of the warm‐water marine mammal Dugong dugon, associated with Aboriginal artefacts, from a Botany Bay salt marsh, marked the beginning of speculation about climate and sea level change in Australia over the period of human occupation. The dugong bones have recently been dated, giving a conventional 14C age of 5520±70 years BP, which is consistent with three older 14C dates for a layer of buried trees that underlies much of the north Botany sediments. The carefully drawn cross‐sections of depositional strata produced by the original discoverers allow further interpretation of the pattern of Holocene sea‐level fluctuations in the Sydney region. Layers of estuarine sediment, such as the one containing the dugong skeleton, are inter‐bedded with peat layers containing in situ roots and stumps, suggesting that the site alternated between sub‐aerial exposure and submergence throughout the Holocene. The presence of the dugong is suggestive of warmer conditions, and its inland location indicates a more extensive Botany Bay in the recent past. This is in agreement with other work from southern New South Wales describing both warm‐water marine species and higher sea levels several thousand years ago.
ACRONYMS BP Radiocarbon years Before Present (1950 AD). CalBP Radiocarbon years Before Present calibrated to tree ring data curves to give a better approximation of true calendar dates.相似文献
3.
Although archaeological evidence may express the results of several seasons of activity, the human skeleton, when correlated with archaeological and ethnographic data, provides information concerning daily activities performed throughout an individual's lifetime. Studies in occupational and sports medicine, along with electromyographic analysis of movement, have shown that different activities place different amounts of stress on human bone. In the present study, analysis of upper extremity musculoskeletal stress markers (MSM) has been used to clarify habitual activity patterns of two ancient Thule Eskimo groups from northwest Hudson Bay, Canada. Distinct pattern differences in muscle use occurred between Thule adult males and females and suggest possible gender-specific activity patterns that are not always discernible from the archaeological record alone. Temporal applications of the MSM data for Early and Late Period Thule support McCartney's theory of a substantial change in subsistence strategies through time, particularly among the adult males. 相似文献
4.
Based on a high resolution regional climate model (RCM) experiment, a climate change scenario for Scotland for the end of this century is constructed with the aim of exploring the added value of utilising a regional rather than a global model (GCM) for climate change scenario construction. Spatial variations in regional seasonal average temperature and precipitation change are analysed and the local response of ‘extreme’ weather events to climate warming is assessed using daily model output. The analyses suggest that in comparison with the GCM, the RCM does not provide fundamentally different patterns of seasonal climate change and daily weather response over Scotland, although it does capture more subtle spatial variations in these changes. The RCM also simulates more realistic daily weather events than the GCM, although the relative changes in the frequencies of daily extremes are not greatly different. However, with the limited length of the single model simulation analysed here, it is not easy to establish how robust and significant are the sub‐national patterns of climate response across Scotland. To improve the quality and comprehensiveness of regional climate change scenario information, a number of research issues remain to be addressed. 相似文献
5.
Wim Carton 《对极》2019,51(3):750-769
Models suggest that climate change mitigation now depends on negative emissions, i.e. the large‐scale removal of carbon dioxide from the atmosphere. This assumption has been criticised in the climate policy literature for being unfeasible and unjust. This article asks how critical scholars can make sense of, and contribute to these debates. It suggests that negative emissions can be conceived of as a spatiotemporal fix that promises to defer the devaluation of fixed capital. But the negative emissions example also challenges us to broaden our conception of how the socioecological contradictions of capitalism can be “fixed”. I outline three ways in which it does this by highlighting the significance of a predominantly temporal fix, the role of hegemonic, sociopolitical interventions involving multiple actors, and the possibility of safeguarding existing production processes. I conclude that spatiotemporal fixes to climate change should be seen as part of a wider political economy of delay in devaluing carbon‐intensive accumulation processes. 相似文献
6.
J. Craig Rose Mary E. F. Bennett Brian D. Bates Walter R. T. Witschey 《Conservation and Management of Archaeological Sites》2018,20(4):215-233
ABSTRACTThe Longwood Institute of Archaeology conducted the Vulnerability, Potential and Condition (VPC) assessment of shoreline archaeological sites along 1990 km (1237 miles) of the Chesapeake Bay in Virginia. VPC assessment involves a three-pronged approach that includes (1) the assessment of site vulnerability due to changing shorelines using an analytical package called Analysing Moving Boundaries Using R – AMBUR, (2) the assessment of potential shoreline site locations through predictive modelling using Weights of Evidence – WofE – analysis, and (3) the assessment of current conditions of known sites through direct observation. Vulnerability assessment results indicated that 49% of site shorelines in the project area are moving landward. Potential assessment located high-probability site locations with an 83% efficiency. Condition assessment, conducted using standard field protocols, provided feedback of the sites’ current conditions. The intended outcome of this method is to provide resource managers with information needed to make informed, data-driven management decisions. 相似文献
7.
Charles F. Merbs 《International Journal of Osteoarchaeology》2002,12(4):279-290
Inuit skeletons from archaeological sites in Arctic Canada were examined for the presence of spondylolysis. The largest series represent the Thule culture and historic Inuit from northwest Hudson Bay and Labrador, and Sadlermiut from Southampton Island. The condition was found in 90 individuals, with a total of 120 affected vertebrae producing 198 hemi‐arch defect sites. As in other studies, L5 is affected most frequently, followed by L4 and L3, but examples of L1, L2, L6, and S1 involvement are represented. Incomplete separations account for 20% (40) of the 198 defects, and 5% (10) occur at sites other than interarticularis. Affected males outnumber females at a ratio of 2.4 to 1. The condition was found to increase in frequency from adolescence to young adulthood, and then decrease to middle adulthood and decrease again to old adulthood, but the drop in frequency with age in the adult categories is significant only at the .20 level. Where comparisons could be made, the data obtained from the Canadian Inuit closely resemble those obtained from Alaskan Eskimos and Aleuts, especially their closest linguistic relatives, Inupiat speakers in northern Alaska. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
8.
Climate change can only be tackled with public support for sustainable policies. Thus, public attitudes towards climate change matter. More than 3 decades of climate change opinion (CCO) research—conducted by geographers, environmental psychologists, behavioural scientists, sociologists etc.—have provided us with a wealth of information about which predictors shape public CCOs. This review synthesises these findings and highlights the different geographies (the self, the nation, the region, the digital) that emerge within this research. Given the increased importance of social media, virtual geographies of climate change scepticism are increasingly being identified. Our paper argues that new research agendas must be developed to address the meshwork of virtual space and small scale geographies (regions, towns, districts) in which CCOs are formed. 相似文献
9.
ABSTRACT Field explorations at the newly recorded Hakaea Beach site, Nuku Hiva, Marquesas Islands were spread across a 12,500 m2 area on the western coastal flat. The site's geomorphic and cultural history is reconstructed based on nine strata and ten radiocarbon determinations. The Hakaea record illustrates the range of powerful environmental processes, including sea level fall, climate change, tsunamis, and tropical storm surges, which have operated on Marquesan shorelines for the last 800 years, and the ease with which past human activity can be obscured or erased. The results highlight the need to systematically search for protected coastal contexts and geomorphic settings where older surfaces might be preserved. Radiocarbon assemblages from the 13th century Hakaea Beach site and seven other early Marquesan sites are considered in light of three models of East Polynesian dispersal: 1) Leap‐frog; 2) Stepping‐stone; and 3) Advancing Wave. Along with chronometrics, the processes and mechanisms which might account for regional patterns of mobility and settlement are emphasized. The Marquesan record is unique amongst central East Polynesian archipelagos in the number of pre‐14th century sites, a pattern that might relate to the antiquity of human settlement, and one which should be considered alongside the late Holocene sea level record. 相似文献
10.
五帝时代(距今6-4千年)中国的气候 总被引：1，自引：0，他引：1
历史学研究表明,古代文献如《史记》记载的五帝:黄帝、颛顼、帝喾、唐尧、虞舜,可能应该视为一个时代,而不局限于五个人。获得较多支持的观点是:这个时代约在6-4kaBP,而且也不限于华夏集团,至少还包括东夷集团、苗蛮集团等。因此,从地望上讲,也不限于中原地区,还包括东部沿海及长江中游。考古学研究表明,6-4kaBP正是新石器时代晚期,后期可称为铜石并用时代。从考古文化来看,中原地区为仰韶文化中、晚期到龙山文化。东部地区为大汶口文化及(山东)龙山文化。其中在3500BC是仰韶文化中、晚期的交界,以及大汶口文化早、中期的交界。环境考古研究表明,6-4kaBP是一个由湿润气候向干旱气候转变的过渡时期。特别6.0-5.6kaBP有湿润气候的证据。4kaBP前后则明显进入晚全新世的干旱期,在此期间还包括5.5kaBP和4.2-4.0kaBP两次气候突变。现代气候资料及模拟研究表明,由早、中全新世的湿润气候向晚全新世的干旱气候转变的主要原因为岁差变化。但是,5.5kaBP及4.2-4.0kaBP的两次冷干气候突变,则可能与热盐环流的突然减弱有关,而热盐环流减弱可能是太阳活动减弱的结果。 相似文献
11.
Changes in the spatial extent and duration of winter snow‐cover, both in Scotland and in a wider global context, have a number of socio‐economic and environmental implications. Evidence from Scottish climatological stations appears to suggest that the most marked decease in the number of days with snow lying has occurred since the late 1970s. Information on the effects of these changes was gathered using a questionnaire which was sent to key stakeholders. Responses suggest deleterious effects on winter recreation and sports, upland habitats and flood regimes in Scottish rivers. An extended snow‐free season has affected access to, and management of, Scottish land. 相似文献
12.
Pride in Australia's extreme climate has long been a part of Australia's national identity. Today, climate continues to be enrolled in a range of nationalistic projects, including the (re)development of climate science and other responses to climate change. In this paper, we outline some of the contours of the ‘Australian national climate’, claims to know it, and four idealised responses to it: bounce back, dismissal, endurance, and migration. We argue that the deeply cultural framing of climate in Australia—in particular, Australians' emphasis on the climate's inherent variability and unknowability, and their own historical adaptability—is being exploited by the federal government and hampering climate change mitigation nationally. 相似文献
13.
LESLEY HEAD 《Geographical Research》2015,53(3):313-320
What does it mean for us to be citizens of the Anthropocene, both individually and collectively? This essay tries to answer that question in order to stimulate a wider conversation about how we should respond to and shape the socioecological transformations ahead of us. 1 1 Many of the ideas and arguments in this essay are explored in greater depth in my book (in preparation), Hope and Grief in the Anthropocene: Re‐conceptualising Human‐Nature Relations (Routledge, UK). Questions of grief are also explored in Head, L. 2016 ‘Grief, loss and the cultural politics of climate change’, a chapter in H. Bulkeley, M. Paterson and J. Stripple (eds) Towards a Cultural Politics of Climate Change: Devices, Desires and Dissent.
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14.
Thomas H. McGovern 《Conservation and Management of Archaeological Sites》2018,20(4):165-174
ABSTRACTThe first decade of the twenty-first century has seen a growing recognition that widespread impacts of climate change (erosion, sea level rise, wildfires, warming soil temperatures) are rapidly destroying archaeological sites and permanently wiping out millennia of cultural heritage and important scientific data on a global scale. This paper provides a brief overview of the efforts of the international archaeological community and its allies to organise a broad and coordinated response to this widespread and urgent threat to our basic record by mobilising at the local, national and international level. The work of the archaeological professional societies has supplemented a growing host of initiatives on multiple scales by national and local governmental agencies, regional research teams, local and Indigenous heritage groups and the international global change scientific community. This paper provides some reflections on the Society for American Archaeology’s Climate Change Strategies and the Archaeological Record team effort from 2015 to 2018, some links to more contacts and resources and some suggestions for future directions. 相似文献
15.
Michael Heilen Jeffrey H. Altschul Friedrich Lüth 《Conservation and Management of Archaeological Sites》2018,20(4):261-284
ABSTRACTClimate change impacts will increase in their frequency and severity in the coming decades, resulting in compromised integrity or destruction of thousands of heritage resources. Efforts are needed to identify, record, and study resources that will be affected. To set research and preservation priorities, the vulnerability of resources to climate change impacts and their importance to scientific research, preservation, and other resource values needs to be understood. We advocate a modelling approach which predicts the location, timing, and severity of climate change impacts; identifies resources at risk, their resource values, and opportunity costs; and prioritises research and preservation options based on these assessments. The need for this approach is illustrated with examples from two coastal areas subject to different impacts and hosting different types of heritage resources: the Atlantic coast of Georgia in the United States and the Wismar Bight along the Baltic Sea in northern Germany. 相似文献
16.
Jim Perry 《International Journal of Heritage Studies》2013,19(5):426-441
UNESCO’s 207 natural heritage World Heritage Properties are at risk from climate change, but risk varies widely among properties. I offer a global model based on multi-model general circulation model (GCM) ensembles, vulnerability and Human Influence (HII), producing the World Heritage Vulnerability Index (WHVI), a measure of relative risk among properties. Nineteen properties are most at risk (i.e. WHVI > mean + 1 SD). Those include islands (i.e. Vallée de Mai, Aldabra, East Rennell, Teide, Laurisilva of Maderia, Isole Eloie, Pitons Management Area, Morne Trois Pitons and Galapagos Islands), coastal properties (i.e. Everglades, Desembarco del Granma, High Coast and Kvarken Archipelago, Doñana, Brazilian Atlantic Islands, Ichkeul and the Sunderbans) and mountainous properties (i.e. the Pyrenees Mont Pérdu, Nanda Devi and the Valley of Flowers, and Mount Kinabalu). Three properties (i.e. Teide, Isole Eloie and the Pitons Management Area) are geologic, apparently relatively resistant to short-term climactic changes. The remaining 16 are likely to respond to climactic changes in the next 40 years; those changes may threaten their World Heritage status. Those properties are where society could most effectively invest in adaptation. I identify adaptive strategies and next steps for proactive climate change adaptation in the 16 natural heritage properties on the World Heritage List most at risk. 相似文献
17.
18.
Marianne Nitter Endre Elvestad Lotte Selsing 《International Journal of Nautical Archaeology》2013,42(1):87-102
Predictions of future requirements for the protection of maritime archaeological sites are made using the fetch method which has been developed to evaluate the quality of landing‐places and navigable channels. The very useful method may explain why archaeological sites along the coast are rare in some areas, but numerous in others. Many of them are vulnerable to destruction by the effects of climate change, especially rising sea‐levels, based on the IPCC scenarios. The objective fetch method can be used worldwide to predict where new finds of sites close to sea‐level can be expected, and also to predict a site's vulnerability. 相似文献
19.
Innovative and effective responses to climate change require that we move beyond reliance on government to include organisations spanning different sectors, such as not‐for‐profit, private, and community groups. Interactions among these organisations in collaborative networks—or “forums”—may provide important mechanisms to successfully address climate change impacts. This paper investigates the relationships between organisational participation and involvement in forums and responses to climate change. Survey data show that people from many organisations are participating in forums and using these meeting points to discuss climate change, even when forums are intended to serve other purposes. The data suggest that participation in any type of forum is related to organisational responses to climate change. Attributes such as type of organisation and knowledge of climate change issues were also found to be related to organisational responses to climate change but these became less important when climate change was discussed in forums. The results of the research suggest that a practical way to increase the volume and variety of organisational responses to climate change may be to encourage participation in forums and/or to influence existing networks to incorporate more discussions of climate change issues. 相似文献
20.
对多年来积累的气候资料的综合分析表明:在全新世期间有两个比较明显的温暖期。它们的时间分别为8～6kaBP(校正成日历年龄大约为9～7calkaBP)和5～3kaBP(日历年龄大约为5.5～3.2calkaBP)。文化的发展很大程度上受到了环境条件的制约。在前一个温暖期的后半段(8～7calkaBP),北方旱作农业(磁山文化、大地湾文化、兴隆洼文化)发展起来。南方稻作农业要在7.0～6.0calkaBP才初具规模。而6.0～5.5calkaBP的气候冷干事件使得南北方文化均有不同程度的衰退,但是南方受到的影响要小于北方。在后一个温暖期到来之后(5.5～3.2calkaBP),分别以龙山文化和良渚文化为代表的南北方新石器文化几乎同时进入发展史上的另一个黄金时代。尽管南北方文化体系对于气候变化的响应有所差异,并且不同时期不同地域文化发展动力也不尽相同,但是从大的时空尺度上来看,我国的新石器时代发展经历了如下阶段:最早期文化萌芽阶段(10calkaBP)——早中新石器时代之间的文化相对衰退期(10～8calkaBP)——新石器时代中期的北方农业文明崛起(8～7calkaBP)——7.0～6.0calkaBP的南方稻作农业的极大发展期——6.0～5.5calkaBP的文化衰退期——新石器时代晚期(5.5～4.0calkaBP)文化的极大繁荣。其间一些大的文化演替或者转型事件的时间在各地也大致相同。说明这种大的文化演进过程还是受到了同一个信号的支配,而只有环境气候因素才可能影响到如此大的范围。 相似文献