检索结果-南通市图书馆

Cryogenic wedges on the NE Qinghai-Tibet and Ordos Plateaus:Their characteristics,origin and OSL dating

Research in Cold and Arid Regions 2021年第6期13卷 463-473页

作者： stuart a.harris Department of Geography University of CalgaryCalgaryAlbertaT2N 1N4Canada

Cryogenic wedges developed due to very cold,rather arid conditions during the maximum of the last cold event when the drying up of the neighboring China Sea resulted in the failure of the East Asian *** the climate ameliorated and the Monsoon rains reappeared,ice-wedges *** warming permitted thawing of the ice infillings accompanied by replacement of the ice by sediments partly from the host ground as well as from the surface by wind or sheet *** cases of extreme surface water flow on slopes after 10 ka B.P.,small baydjarakhs typically c.50 cm high developed,only to have the resulting hollows infilled by sediments carried by wind and/or sheet *** shallow structures form a network on top of many of the cryogenic *** complex history makes dating the ages of the wedges difficult using OSL ***,past field work ignored the problem of the angle of the cut face to the direction of the wedge infilling when sampling the contents of the narrow wedges,resulting in potential contamination of the samples with the host *** of the larger deposits should be alright,but the likelihood of contamination makes the interpretation of the resulting OSL dates from the narrow wedges *** wedges consisting of primary mineral infillings should still have similar OSL dates with depth for a given wedge,but the distinction between ice-wedge infillings and soil wedges is difficult since both can exhibit older dates of the infillings with *** available data suggests that ice-wedges were significantly more common than sediment-filled primary wedges.A protocol to avoid having to obtain large numbers of OSL dates by more careful field sampling and the use of grain size determinations is provided in the Appendix.

关键词： cryogenic wedges OSL dating NE Qinghai-Tibet Plateau differentiation of primary and secondary wedges baydjarakhs in arid climates

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Identification,characteristics and classification of cryogenic block streams

引用

Research in Cold and Arid Regions 2016年第3期8卷 177-186页

作者： stuart a.harris Department of Geography University of CalgaryCanada T2N 1N4

Cryogenic block streams consist of a stream of rocks superficially resembling a stream deposit but lacking a matrix, usually occurring on a valley or gully floor or on slopes that are less steep than the maximum angle of repose of coarse sediments. They are usually formed on perennially frozen ground, but can also occur as relict landforms. There are three main active kinds forming today, viz., Siberian and Tibetan dynamic rock streams and lag block streams. During their formation, the blocks in the active Siberian and Tibetan dynamic block streams move downslope at up to 1 rn/a. They are forming today on the Tibetan Plateau and in the more arid parts of south-central Siberia, although the processes involved in the movement are different. In the case of the Tibetan type, individual blocks slide downslope over the substrate in winter on an icy coating in areas of minimal winter precipitation. The Siberian type develops in areas of 15-80 cm of winter snow cover and an MAAT （mean annual air temperature） of-4 ~C to -17 ~C. The movement is due to creep of snow and ice and collapse of the blocks downslope during thawing. Lag block streams are formed by meltwater flowing over the surface of sediment consisting primarily of larger blocks with a limited amount of interstitial sediment. The erosion of the matrix is primarily in the spring in areas of higher winter precipitation on 10^-30~ slopes. The blocks remain stationary, but the interstitial sediment is washed out by strong seasonal flows of meltwater or rain to form an alluvial fan. The boulders undergo weathering and become more rounded in the process. Lag block streams can also develop without the presence of permafrost in areas with cold climates or glaciers. Block streams also occur as relict deposits in older deposits under various climatic regimes that are unsuitable for their formation today. An example of relict lag block streams with subangular to subrounded blocks occurs in gullies on the forested mountainside

关键词： active dynamic block streams felsemeer relict block steams Tibetan type block streams Siberian typeblock streams lag block streams

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Probable effects of heat advection on the adjacent environment during oil production at Prudhoe Bay, Alaska

引用

Research in Cold and Arid Regions 2016年第6期8卷 451-460页

作者： stuart a.harris Department of Geography University of Calgary Calgary Alberta T2N 1N4 Canada

The latest available data for mean annual air temperature at sites away from the Arctic coast in both Alaska and the Yukon Territory show no significant warming in the last 30-50 years. However, around the Arctic coast of northwest North America centered on Prudhoe Bay, the weather stations show significant warming of both the air and the ocean water, resulting in substantial losses in sea ice west of Prudhoe Bay. These changes appeared shortly after the commencement of shipment of oil through the Trans-Alaska Pipeline in 1977, but have now reached a quasi-stable thermal state. Since more than 17 trillion barrels of oil have passed through the pipeline after being cooled by the adjacent air, which in turn, can then result in the melting of the adjacent sea ice, there appears to be a very strong relationship between these events, and a marked lack of correlation with the changes of the content of greenhouse gases in the atmosphere. This contrasts with the IPCC interpretation of the available climatic data, which assumes that the maximum climatic warming at Prudhoe Bay is typical of the entire region and is the result of increasing greenhouse gases. Engineers need to consider heat advection by oil or gas from underground when designing pipeline facilities, and to take account of the potential environmental con-sequences that they may cause.

关键词： Prudhoe Bay mean annual air temperature heat advection due to oil Arctic ice cover Trans-Alaska Pipeline greenhouse gases Arctic marine ecosystems

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Climate change and permafrost stability in the eastern Canada Cordillera:The results of 33 years of measurements

引用

Research in Cold and Arid Regions 2009年第5期1卷 381-403页

作者： stuart a.harris Department of Geography University of Calgary

Over the last 33 years,a network of climate stations has been set up at high altitude mountain permafrost sites from Plateau Mountain near Claresholm,Alberta,north to Sheldon Lake on the North Canol Road in the *** together with the data from the US National Weather Service and the Canadian Atmospheric Environment Service,the results indicate a cooling of mean annual air temperature south of Calgary,no significant change in Calgary,a slight warming at Jasper,and a major warming at Summit Lake,west of Fort *** contrast,the south eastern and central Yukon show only a minor warming trend that lies well within the limits of a sixty-year record measured by the Canadian Atmospheric Environment *** the Mackenzie valley and on the North Slope of Alaska,the mean annual air temperature is *** is aggrading on Plateau Mountain,degrading at Summit Lake,and appears to be stable in southern Yukon and southern *** is in contrast to the warming occurring on the Arctic coastal plain and along the Mackenzie *** therefore appears that changes in climate vary considera-bly from place to place,and even where warming may occur,it may not continue *** has been a northward shift of the arctic front due to a weakening of air pressure in the Yukon and Alaska relative to the continental tropical(cT) and maritime polar(mT) air masses to the *** actual changes that may be occurring appear to undergo amplification along the Mackenzie valley and Arctic coastal plain and reduction by buffering in the interior Yukon and Alaskan mountains,a result of mi-cro-environmental ***,careful monitoring of the climate is required and needs to be expanded in the National Parks in the mountains in order to provide data on the changes that may be taking *** measurements can provide a sound basis for interpreting ecological and other climate-related *** existing climate models are not working satisfactorily because w

关键词： permafrost stability long-term measurement climate change the Eastern Canada Cordillera

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Impacts of degrading permafrost on streamflow in the source area of Yellow River on the Qinghai-Tibet Plateau,China

引用

Advances in Climate Change Research 2019年第4期10卷 225-239页

作者： MA Qiang JIN Hui-Jun Victor F.BENSE LUO Dong-Liang Sergey S.MARCHENKO stuart a.harris LAN Yong-Chao State Key Laboratory of Frozen Soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China School of Civil Engineering Harbin Institute of TechnologyHarbin150090China Hydrology and Quantitative Water Management Group Department of Environmental SciencesWageningen UniversityWageningen6708PBthe Netherlands Geophysical Institute(GIPL) University of Alaska FairbanksFairbanks99775USA Department of Geography University of CalgaryCalgaryT3A 1E4Canada

Many observations in and model simulations for northern basins have confirmed an increased streamflow from degrading permafrost,while the streamflow has declined in the source area of the Yellow River(SAYR,above the Tanag hydrological station)on the northeastern Qinghai-Tibet Plateau,West *** and to what extent does the degrading permafrost change the flow in the SAYR?According to seasonal regimes of hydrological processes,the SAYR is divided intofour sub-basins with varied permafrost extents to detect impacts of permafrost degradation on the Yellow River *** show that permafrost degradation may have released appreciable meltwater for recharging *** potential release rate of ground-ice melt-water in the Sub-basin 1(the headwater area of the Yellow River(HAYR),above the Huangheyan hydrological station)is the highest(5.6 mm per year),contributing to 14.4%of the annual Yellow River streamflow at ***/intra-and annual shifts of streamflow,a possible signal for the marked alteration of hydrological processes by permafrost degradation,is observed in the HAYR,but the shifts are minor in other sub-basins in the *** hydraulic connectivity is expected to occur during and after certain degrees of permafrost *** impacts of permafrost degradation on the annual Yellow River streamflow in the SAYR at Tanag,i.e.,from the meltwater of ground-ice,is estimated at 4.9%that of the annual Yellow River discharge at Tanag,yet with a high uncertainty,due to neglecting of the improved hydraulic connections from permafrost degradation and the flow generation conditions for the ground-ice *** evapotranspiration,substantial weakening of the Southwest China Autumn Rain,and anthropogenic disturbances may largely account for the declined streamflow in the SAYR.

关键词： Streamflow Warming climate Permafrost degradation Streamflow patterns Source area of Yellow River(SAYR)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tessellons, topography, and glaciations on the Qinghai-Tibet Plateau

引用

Research in Cold and Arid Regions 2018年第3期10卷 187-206页

作者： stuart a.harris Hui Jun Jin Rui Xia He Si Zhong Yang Department of Geography University of Calgary State Key Laboratory of Frozen Soils Engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences

The Qinghai-Tibet Plateau has developed into a vast fortress-like structure that has recently presented a barrier limiting the egress of moisture-bearing air masses. Lower sea levels also affected the climate. This paper examines their effects on the current evidence for the timing of past glaciations, and the development and evolution of permafrost. There are two theories regarding glaciation on the Qinghai-Tibet Plateau （QTP）. Kuhle suggested that there was a major, unified ice-cap during the Last Glacial Maximum （LGM）, whereas major Chinese glaciologists and others have not found or verified reliable evidence for this per se. There have been limited glaciations during the last 1.1 Ma B.P. but with increasing dominance of permafrost including both primary and secondary tessellons infilled with rock, sand or loess. The East Asia Monsoon was absent in this area during the main LGM, starting at 〉30 ka B.P. on the plateau, with sufficient precipitation reappearing about 19 ka B.P. to produce ice-wedges. A weak Megathermal event took place between 8.5 and 6.0 ka B.P., followed by Neoglacial events exhibiting peak cold at 5.3-4.7 ka, 3.1-1.5 ka, and the Little Ice Age （LIA） after 0.7 ka. Subsequently, mean annual air temperature has increased by 4 ℃.

关键词： glaciation of the Qinghai-Tibet Plateau (QTP) tessellons East Asia Monsoon Last Glacial Maximum (LGM) Neoglaciation Asian climate change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evolution of permafrost in Northeast Chinasince the Late Pleistocene

引用

Research in Cold and Arid Regions 2016年第4期8卷 269-296页

作者： HuiJun Jin XiaoLi Chang DongLiang Luo RuiXia He LanZhi Lu SiZhong Yang DongXin Guo XueMei Chen stuart a.harris State Key Laboratory of Frozen Soils Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Gansu 730000 China National-Local Joint Engineering Laboratory of Geo-Spatial Information Technology Hunan University of Science and Technology Xiangtan Hunan 411201 China GFZ German Research Centre for Geosciences Telegrafenberg D-14473 Potsdam Germany College of Resources and Environment Lanzhou University Lanzhou Gansu 730000 China Department of Geography University of Calgary Calgary Alberta Canada T2N 1N4

In Northeast China, permafrost advanced and retreated several times under the influences of fluctuating paleo-climatesand paleo-environments since the Late Pleistocene. During the last 60 years, many new data were obtained and studies wereconducted on the evolution of permafrost in Northeast China, but so far no systematic summary and review have been *** on sedimentary sequences, remains of past permafrost, paleo-flora and -fauna records, and dating data, permafrostevolution since the Late Pleistocene has been analyzed and reconstructed in this paper. Paleo-temperatures reconstructedfrom the remains of past permafrost and those from paleo-flora and -fauna are compared, and thus the southern limitof permafrost （SLP） in each climate period is inferred by the relationship of the permafrost distribution and the meanannual air/ground temperatures （MAAT/MAGT）. Thus, the evolutionary history of permafrost is here divided into fivestages：（1） the Late Pleistocene （Last Glaciation, or LG）（65 to 10–8.5 ka）, the Last Glaciation Maximum （LGM, 21–13 ka）in particular, the coldest period in the latest history with a cooling of about 6~10 °C, characterized by extensive occurrencesof glaciation, flourishing Mammathas-Coelodonta Faunal Complex （MCFC）, widespread aeolian deposits, and significantsea level lowering, and permafrost greatly expanded southwards almost to the coastal plains （37°N–41°N）; （2） the HoloceneMegathermal Period （HMP, 8.5–7.0 to 4.0–3.0 ka）, 3~5 °C warmer than today, permafrost retreated to about 52°N; （3） theLate Holocene Cold Period （Neoglaciation）（4.0–3.0 to 1.0–0.5 ka）, a cooling of 1~3 °C, some earlier thawed permafrost wasrefrozen or attached, and the SLP invaded southwards to 46°N; （4） the Little Ice Age （LIA, 500 to 100–150 a）, the latestcold period with significant permafrost expansion; and （5） climate warming since the last century, during which NortheastChina has undergone extensive permafrost degradation. The frequent and substantial expansio

关键词： Last Glaciation (LG) Holocene Megathermal Period (HMP) Neoglaciation Little Ice Age (LIA) NortheastChina permafrost evolution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Active Lag Block Streams in the Chinese Tian Shan

Active Lag Block Streams in the Chinese Tian Shan

引用

Asian Conference on Permafrost

作者： stuart a.harris Guodong Cheng Cui Zhijiu Department of Geography University of Calgary Cold and Arid Regions Environmental and Engineering Research Institute Department of Geography Peking University

Active lag block streams are forming today in the mountains of the Chinese Tian Shan above treeline near cold-based *** annual air temperatures are below-5.4℃while the mean annual precipitation exceeds 420 *** paper describes the three main types of situation in which they occur（drainage from a hanging valley,gullies on a steeply sloping valley wall,and in front of an end moraine）,together with their *** favoring their formation include continuous permafrost,sediments with abundant large blocks,incipient sorted patterned ground,a discontinuous vegetation cover,steep slopes,high precipitation and a fairly thick winter snow *** started,washing out of the finer interstitial material leaving behind the blocks will occur with every spring snow melt and heavy precipitation *** results are important since they appear to provide the first description of active lag block streams being *** block streams are rather common in many parts of the world,but their conditions of formation have been the subject of considerable debate in the absence of any known modern analogues.

关键词： Active lag block streams Tian Shan continuous permafrost sorted patterned ground end moraines permafrost hydrology

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Climatic change: Causal correlations over the last 240 Ma

引用

Research in Cold and Arid Regions 2013年第3期5卷 259-274页

作者： stuart A. harris Department of Geography University of Calgary

The climate of the Earth has been oscillating between mega warm periods and mega cold periods for 3,000 Ma. Each mega cold period included alternating major warm and cold events. The present mega cold period commenced about 44 Ma in the polar re- gions as the seas cooled following the loss of the circum-equatorial ocean. Before then, a mega warm period lasted for more than 200 Ma. The frequency of the major cold events within the present mega cold period is increasing, with each continent being un- der the influence of a different set of climatic controls. There are many causes of these shifts in climate, ranging from fluctuating meridional ocean currents, rearrangement of tectonic plates, and changes in ocean gateways. These are enhanced by a combination of Milankovitch cycles and many other medium to small oscillations and cyclic controls that cause the daily, monthly, and season- al fluctuations in weather. Examples are given of how these can cause a change from cold to warm events, or vice versa, at pre- sent-day or mega scales, aided by eustatic changes in sea levels and changes in the distribution of air masses, sea ice, and snow.

关键词： climatic change main causes of glaciations and permafrost events main causes of interglacials climatic effects of plate tectonics effects of changing land and sea areas mega cold and mega warm events

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

‘Are We Running out of Planet to Exploit?’ Links and Limits in the Global Resources Chain?

引用

Contemporary International Relations 2011年第3期21卷 56-75页

作者： stuart harris School of International Political and Strategic StudiesCollege of Asia and the PacificThe Australian National University

Many people have begun to concern about the potential resources shortages against the backdrop of rapid economic *** Krugman wrote an article titled ‘Running out of Planet to exploit’,and in this article,the author will address the Krugman question,and to consider whether the key factor is the decision-making capacity of the international community in dealing with and adapting to the substantial interactions between energy,land,water,and food supply,and the potential global resource scarcities in these four areas—the links and limits in the paper's title.

关键词：资源短缺运行行星链接国际社会适应能力食品供应相互作用

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：