Perspectives on present-day sea level change: a tribute to Christian le Provost     

Alix Lombard  Anny Cazenave  Pierre Yves Le Traon  Stephanie Guinehut  Cécile Cabanes 《Ocean Dynamics》2006,56(5-6):445-451

In this paper, we first discuss the controversial result of the work by Cabanes et al. (Science 294:840–842, 2001), who suggested that the rate of past century sea level rise may have been overestimated, considering the limited and heterogeneous location of historical tide gauges and the high regional variability of thermal expansion which was supposed to dominate the observed sea level. If correct, this conclusion would have solved the problem raised by the IPCC third assessment report [Church et al, Cambridge University Press, Cambridge, pp 881, 2001], namely, the factor two difference between the 20th century observed sea level rise and the computed climatic contributions. However, recent investigations based on new ocean temperature data sets indicate that thermal expansion only explains part (about 0.4 mm/year) of the 1.8 mm/year observed sea level rise of the past few decades. In fact, the Cabanes et al.’s conclusion was incorrect due to a contamination of abnormally high ocean temperature data in the Gulf Stream area that led to an overestimate of thermal expansion in this region. In this paper, we also estimate thermal expansion over the last decade (1993–2003), using a new ocean temperature and salinity database. We compare our result with three other estimates, two being based on global gridded data sets, and one based on an approach similar to that developed here. It is found that the mean rate of thermosteric sea level rise over the past decade is 1.5±0.3 mm/year, i.e. 50% of the observed 3 mm/year by satellite altimetry. For both time spans, past few decades and last decade, a contribution of 1.4 mm/year is not explained by thermal expansion, thus needs to be of water mass origin. Direct estimates of land ice melt for the recent years account for about 1 mm/year sea level rise. Thus, at least for the last decade, we have moved closer to explaining the observed rate of sea level rise than the IPCC third assessment report.  相似文献   

东北夏季气温变异的区域差异及其与大气环流和海表温度的关系   总被引：17，自引：2，他引：17       下载免费PDF全文

孙建奇  王会军 《地球物理学报》2006,49(3):662-671

利用1951～2000年中国东北地区23个台站资料，对东北夏季气温的时空分布进行了研究，发现其变化除具有整体的一致性外，东北南部和北部的夏季气温在年际和年代际时间尺度都表现出很大不同，其中北部区域的夏季气温在1987～1988年间发生了一次显著的气候突变. 另外，剔除夏季气温全区一致变化的年份后，南北两区夏季气温与大气环流和海表温度的关系表明：突变前，影响北部和南部冷/热夏季的大气环流形势存在显著的不同，关键海域亦有很大差异：影响南部的为中纬度西太平洋和印度洋部分海域，影响北部的主要为ENSO事件；突变后，两区的夏季气温及相应大气环流和关键海区都趋于一致. 在整个分析时段内，北部夏季气温与东亚夏季风存在显著负相关，而南部的关系则不明显.  相似文献   

EXPERIMENTS OF A REDUCED GRID IN LASG/IAPWORLD OCEAN GENERAL CIRCULATION MODELS (OGCMs)     

刘喜迎  刘海龙  张学洪  宇如聪 《热带气象学报(英文版)》2006,12(1):9-15

Due to the decrease in grid size associated with the convergence of meridians toward the poles in spherical coordinates, the time steps in many global climate models with finite-difference method are restricted to be unpleasantly small. To overcome the problem, a reduced grid is introduced to LASG/IAP world ocean general circulation models. The reduced grid is implemented successfully in the coarser resolutions version model L30T63 at first. Then, it is carried out in the improved version model LICOM with finer resolutions. In the experiment with model L30T63, under time step unchanged though, execution time per single model run is shortened significantly owing to the decrease of grid number and filtering execution in high latitudes. Results from additional experiments with L30T63 show that the time step of integration can be quadrupled at most in reduced grid with refinement ratio 3. In the experiment with model LICOM and with the model’s original time step unchanged, the model covered area is extended to the whole globe from its original case with the grid point of North Pole considered as an isolated island and the results of experiment are shown to be acceptable.  相似文献   

Multiple exposures and dynamic vulnerability: Evidence from the grape industry in the Okanagan Valley, Canada   总被引：7，自引：1，他引：7  

Suzanne Belliveau  Barry Smit  Ben Bradshaw 《Global Environmental Change》2006,16(4):364-378

This paper assesses the vulnerability of grape growers and winery operators in the Okanagan Valley, British Columbia to climate variability and change, in the context of other sources of risk. Through interviews and focus groups, producers identified the climatic and non-climatic risks relevant to them and the strategies employed to manage these risks. The results show that the presence of multiple exposures affects the way in which producers are vulnerable to climate change. Producers are vulnerable to conditions that not only affect crop yield, but also affect their ability to compete in or sell to the market. Their sensitivity to these conditions is influenced in part by institutional factors such as trade liberalization and a “markup-free delivery” policy. Producers’ ability to adapt or cope with these risks varies depending on such factors as the availability of resources and technology, and access to government programmes. Producers will likely face challenges associated with the supply of water for irrigation due to a combination of climatic changes and changing demographics in the Okanagan Valley, which in turn affect their ability to adapt to climatic conditions. Finally, adaptations made by producers can change the nature of the operation and its vulnerability, demonstrating the dynamic nature of vulnerability.  相似文献   

Effects of climate change on coastal fresh groundwater resources   总被引：1，自引：0，他引：1  

Priyantha Ranjan  So Kazama  Masaki Sawamoto 《Global Environmental Change》2006,16(4):388-399

This study evaluates the impacts of climate change on fresh groundwater resources specifically salinity intrusion in water resources stressed coastal aquifers. Our assessment used the Hadley Centre climate model, HadCM3 with high and low emission scenarios (SRES A2 and B2) for years 2000–2099. In both scenarios, the annual fresh groundwater resources losses indicate an increasing long-term trend in all stressed areas, except in the northern Africa/Sahara region. We also found that precipitation and temperature individually did not show good correlations with fresh groundwater loss. However, the relationship between the aridity index and fresh groundwater loss exhibited a strong negative correlation. We also discuss the impacts of loss of fresh groundwater resources on socio-economic activities, mainly population growth and per capita fresh groundwater resources.  相似文献   

广西2005年气候特点及其影响评价   总被引：12，自引：2，他引：12  

黄雪松  李艳兰 《广西气象》2006,27(1):20-23

2005年，广西大部地区气温偏高、降水量偏少、日照时数偏少。年内出现了干旱、暴雨洪涝、强对流天气、高温天气等气候事件，其中以干旱和暴雨洪涝最为突出，2005年气候灾害属偏重年份。气候对社会经济的影响有利有弊。  相似文献   

超级终端在自动站维护中的应用   总被引：12，自引：0，他引：12  

殷明洁 《广西气象》2006,27(1):55-57

利用Windows操作系统中的超级终端检测、判断自动站采集器的状态，同时可对已缺测的正点数据进行补救。  相似文献   

“05．6”广西持续性大暴雨成因分析   总被引：17，自引：0，他引：17  

黎惠金 《广西气象》2006,27(3):22-25

利用常规资料、T213初始场及6h预报场、卫星云图等资料，用中尺度分析方法，并配合诊断分析，对广西“05.6”持续性大暴雨成因进行了初步探讨。结果表明：这次过程是在稳定的大尺度环流形势和有利的物理量场条件下发生，是大、中尺度天气系统相互作用的结果，具有典型的中尺度性质，表现出强降雨的不均匀性、突发性和局地性，是中尺度天气系统活动的结果。  相似文献   

对企业会计信息失真现象的探讨     

李秀蓉 《中国煤田地质》2006,18(5):67-69

针对企业会计信息失真的一些现象，分析了产生原因，阐述了给国家、社会甚至企业自身带来的危害性，并提出了建立惩处机制，监督约束机制，推行会计委派制，完善会计监督体系，提高职业道德等相应的治理建议。  相似文献   

布卡拉曼加拉贝氏牙形石动物群在西藏日土地区的发现及其意义     

纪占胜姚建新  武桂春刘贵忠 《地质通报》2006,25(1):142-145

布卡拉曼加拉贝氏牙形石动物群首次在西藏阿里日土县多玛区脱塔拉剖面的吞龙共巴组底部发现,主要由Rabeignathus bucaramangus,Sweetognathus whitei,Sweetognathus ironatus和Mesogondolella cf.bissilli组成,指示的地层时代为Artinskian中晚期-Kungurian早期.此前,该动物群仅发现于美国犹他州、堪萨斯州、哥伦比亚的布卡拉曼加、帕米尔东南部和中国滇西保山地区.该牙形石动物群的产出地点位于班公湖以北、龙木错以南的喀喇昆仑地层分区,跨越了班公湖-怒江断裂带北界,而这一动物群被认为是冈瓦纳北缘浅海区特有的浅水相类型,因此推测班公湖-怒江缝合带可能不是冈瓦纳大陆的北界.  相似文献