华北地区夏季水资源特征分析及其对气候变化的响应(Ⅱ): 华北地区夏季水量丰、枯与气候变化的关系   总被引：15，自引：5，他引：10  

范广洲  吕世华  程国栋 《高原气象》2002,21(1):45-51

利用NCEP／NCAR近40年的再分析资料,简单统计分析了华北地区夏季（7－8月）气温或（和）降水变化对该区夏季水资源的影响。结果表明,华北地区夏季水量丰、枯与气温、降水有较好的相关关系。文中还建立了气温或（和）降水变化对水资源各分量影响的简单统计评估模型。利用这些模型,模拟研究了华北地区水资源各分量对不同气候变化情况的响应,取得了一些有意义的结构。  相似文献   

A multi-proxy lacustrine record of Holocene climate change on northeastern Baffin Island, Arctic Canada   总被引：3，自引：0，他引：3  

Jason P. Briner  Neal Michelutti  Donna R. Francis  Gifford H. Miller  Yarrow Axford  Matthew J. Wooller  Alexander P. Wolfe 《Quaternary Research》2006,65(3):431-442

Reconstructions of past environmental changes are critical for understanding the natural variability of Earth's climate system and for providing a context for present and future global change. Radiocarbon-dated lake sediments from Lake CF3, northeastern Baffin Island, Arctic Canada, are used to reconstruct past environmental conditions over the last 11,200 years. Numerous proxies, including chironomid-inferred July air temperatures, diatom-inferred lakewater pH, and sediment organic matter, reveal a pronounced Holocene thermal maximum as much as 5°C warmer than historic summer temperatures from 10,000 to 8500 cal yr B.P. Following rapid cooling 8500 cal yr B.P., Lake CF3 proxies indicate cooling through the late Holocene. At many sites in northeastern Canada, the Holocene thermal maximum occurred later than at Lake CF3; this late onset of Holocene warmth is generally attributed to the impacts of the decaying Laurentide Ice Sheet on early Holocene temperatures in northeastern Canada. However, the lacustrine proxies in Lake CF3 apparently responded to insolation-driven warmth, despite the proximity of Lake CF3 to the Laurentide Ice Sheet and its meltwater. The magnitude and timing of the Holocene thermal maximum at Lake CF3 indicate that temperatures and environmental conditions at this site are highly sensitive to changes in radiative forcing.  相似文献   

Why radiative forcing might fail as a predictor of climate change     

Nicola Stuber  Michael Ponater  Robert Sausen 《Climate Dynamics》2005,24(5):497-510

Radiative forcing has been widely used as a metric of climate change, i.e. as a measure by which various contributors to a net surface temperature change can be quantitatively compared. The extent to which this concept is valid for spatially inhomogeneous perturbations to the climate system is tested. A series of climate model simulations involving ozone changes of different spatial structure reveals that the climate sensitivity parameter is highly variable: for an ozone increase in the northern hemisphere lower stratosphere, it is more than twice as large as for a homogeneous CO₂ perturbation. A global ozone perturbation in the upper troposphere, however, causes a significantly smaller surface temperature response than CO₂. The variability of the climate sensitivity parameter is shown to be mostly due to the varying strength of the stratospheric water vapour feedback. The variability of the sea-ice albedo feedback modifies climate sensitivity of perturbations with the same vertical structure but a different horizontal structure. This feedback is also the origin of the comparatively larger climate sensitivity to perturbations restricted to the northern hemisphere extratropics. As cloud feedback does not operate independently from the other feedbacks, quantifying its effect is rather difficult. However, its effect on the variability of for horizontally and vertically inhomogeneous perturbations within one model framework seems to be comparatively small.This revised version was published online March 2005 with corrections to table 5.  相似文献   

青藏高原地区过去2000年来的气候变化   总被引：14，自引：0，他引：14  

杨保 《地球科学进展》2003,18(2):285-291

依据冰芯、树轮、沉积物分析和冰川波动等各单点古气候代用资料,以及重建的综合温度变化曲线,分析了近 2000年青藏高原温度变化的整体性和区域性特征。全青藏高原综合温度曲线显示中世纪暖期（1150-1400年）、小冰期（1400-1900年）以及公元 3～5世纪冷期的存在。青藏高原温度变化具有明显的区域性特征。在 9～11世纪,青藏高原东北部以温暖为特征,而青藏高原南部和西部表现为寒冷。青藏高原南部和西部分别于1150-1400年（此时段在高原东北部表现为弱暖期）和1250-1500年经历了气候变暖。与中国东部文献记录的最新综合研究结果比较,高原东北部与中国东部的温度变化最为一致。而且,许多重大气候事件,如1100-1150年、1500-1550年、1650-1700年和1800-1850年的冷事件在高原和中国东部同时出现,而后 3次冷期与小冰期期间中国西部发生的冰川前进相匹配。  相似文献   

全球闪电活动与气候变化   总被引：5，自引：0，他引：5  

郄秀书 《干旱气象》2003,21(3):69-73

全球闪电活动与气候变化关系的研究正受到越来越多的重视,该文从卫星上观测到的全球闪电活动、闪电活动和全球电路对温度的响应,闪电和对流层上部水汽的联系,闪电和N0,等几方面进行了阐述,指出了闪电活动在气候变化研究中的重要性。同时,文中还对影响闪电活动和起电过程的热力动力作用以及气溶胶的作用等进行了分析。  相似文献   

Climate change,carbon dependency and narratives of transition and stasis in four English rural communities     

《Geoforum》2015

This paper explores the carbon dependency of life in four villages in England, the degree to which residents in these villages are aware of and concerned about this dependency and its relationship to climate change, and the extent to which they undertake actions that might mitigate or adapt to this dependency. The paper identifies high degrees of carbon dependency and awareness and concern about climate change and carbon dependency, although relatively low levels of mitigative or adaptive actions. The paper explores how this disjuncture between awareness and actions persists, arguing that attention needs to be paid to how people narrate stories to themselves and others that account for inaction. Five narratives of non-transition or stasis are identified, along with three, less widely adopted, narratives of transition. The significance of rurality and emotions within these narratives is highlighted.  相似文献   

Global water resources modeling with an integrated model of the social-economic-environmental system   总被引：3，自引：0，他引：3  

Evan G.R. Davies  Slobodan P. Simonovic 《Advances in water resources》2011,34(6):684-700

Awareness of increasing water scarcity has driven efforts to model global water resources for improved insight into water resources infrastructure and management strategies. Most water resources models focus explicitly on water systems and represent socio-economic and environmental change as external drivers. In contrast, the system dynamics-based integrated assessment model employed here, ANEMI, incorporates dynamic representations of these systems, so that their broader changes affect and are affected by water resources systems through feedbacks. Sectors in ANEMI therefore include the global climate system, carbon cycle, economy, population, land use and agriculture, and novel versions of the hydrological cycle, global water use and water quality. Since the model focus is on their interconnections through explicit nonlinear feedbacks, simulations with ANEMI provide insight into the nature and structure of connections between water resources and socio-economic and environmental change. Of particular interest to water resources researchers and modelers will be the simulated effects of a new water stress definition that incorporates both water quality and water quantity effects into the measurement of water scarcity. Five simulation runs demonstrate the value of wastewater treatment and reuse programs and the feedback-effects of irrigated agriculture and greater consumption of animal products.  相似文献   

柴达木盆地大浪滩地区表层芒硝的形成时代及环境意义          下载免费PDF全文

马妮娜  郑绵平  马志邦 《地质学报》2011,85(3):433-444

通过对柴达木盆地大浪滩地区的两次实地勘查,发现小梁山多处可见芒硝—碳酸盐粘土互层的露头,选取了完整沉积的D26剖面进行研究。比较盐湖学的研究表明,芒硝是典型的冷相盐类矿物;而碳酸盐粘土和石膏则反映了相对温暖潮湿和温暖的环境。本文通过对芒硝—碳酸盐粘土互层的矿物鉴定,石膏的铀系不平衡法定年,以及结合碳酸盐粘土的碳氧同位素分析,首次揭示出大浪滩地区在倒数第二次冰期（MIS 6阶段）前后经历了偏暖潮湿期（＞195.1 ka BP）→寒冷干旱期（195.1 ~ 169.9 ka BP）→偏暖湿期（169.9 ka BP ka BP）→冷暖交替时期（169.9 ka BP ~ 118 ka BP）→偏暖湿期（118 ka BP）的气候演变序列。经与黄土剖面,深海氧同位素和区域研究资料的对比表明,自中晚更新世以来,大浪滩地区不仅受到区域地质活动的影响,也与全球的气候变化同步响应。  相似文献   

Late Pleistocene climatic change in the French Jura (Gigny) recorded in the δO of phosphate from ungulate tooth enamel     

Magali Fabre  Christophe Lcuyer  Jean-Philip Brugal  Romain Amiot  Franois Fourel  Franois Martineau 《Quaternary Research》2011,75(3):605-613

Oxygen isotope compositions of phosphate in tooth enamel from large mammals (i.e. horse and red deer) were measured to quantify past mean annual air temperatures and seasonal variations between 145 ka and 33 ka in eastern France. The method is based on interdependent relationships between the δ¹⁸O of apatite phosphate, environmental waters and air temperatures. Horse (Equus caballus germanicus) and red deer (Cervus elaphus) remains have δ¹⁸O values that range from 14.2‰ to 17.2‰, indicating mean air temperatures between 7°C and 13°C. Oxygen isotope time series obtained from two of the six horse teeth show a sinusoidal-like signal that could have been forced by temperature variations of seasonal origin. Intra-tooth oxygen isotope variations reveal that at 145 ka, winters were colder (? 7 ± 2°C) than at present (3 ± 1°C) while summer temperatures were similar. Winter temperatures mark a well-developed West–East thermal gradient in France of about ? 9°C, much stronger than the ?4°C difference recorded presently. Negative winter temperatures were likely responsible for the extent and duration of the snow cover, thus limiting the food resources available for large ungulates with repercussions for Neanderthal predators.  相似文献   

Paleogene carbon isotope excursions in the Bunkers Hill borehole: Hampshire Basin, UK     

Emma Hodgson  Stephen T. Grimes  Gregory D. Price  Meriel E.J. Fitzpatrick  Malcolm B. Hart  Melanie J. Leng 《Proceedings of the Geologists' Association. Geologists' Association》2011,122(3):460-471

This study demonstrates that the Bunkers Hill borehole, which is located within the Hampshire Basin, contains a carbon isotope excursion (CIE) in the Upnor Formation followed by a positive recovery from another CIE within the overlying Reading Formation. This study has also shown that the CIE in the Upnor Formation predates the Paleocene/Eocene Thermal Maximum (PETM), while the carbon isotope recovery at the base of the Reading Formation is most likely related to it. The positive carbon isotope trend, before a return to more negative values, seen throughout the majority of the Reading Formation can also be seen in coeval deposits in the Jubilee 404T borehole in the London Basin and in the Tienen Formation in the Doel and Kallo boreholes from the Belgium Basin. This indicates that this post-PETM carbon isotope signal may, therefore, be regional if not global in nature.  相似文献