全球变暖停滞的研究进展回顾

1998—2012年,全球平均地面增温速率较之前明显趋缓,出现全球变暖停滞现象,该现象的成因与机制是当前气候变化研究的一个热点领域。主要从外部强迫和内部变率2个角度回顾全球变暖停滞产生机制的研究进展。从气候系统外部强迫影响来说,全球变暖停滞主要受到太阳活动、火山爆发、气溶胶以及平流层水汽等的影响。从气候系统内部调控作用来看,全球增温速率减缓主要受到太平洋、大西洋、印度洋和南大洋自然变率以及相应的热量再分配过程的影响。全球变暖停滞期间气候系统内部能量并没有减少,其中一部分能量被转移并储存在了海洋中深层,从而对全球增温减缓产生影响。同时,重点回顾了针对部分耦合强迫作用的"起搏器"试验,该类试验是研究全球变暖停滞的特征、成因及机制的有力手段。此外,也总结了全球变暖停滞现象对气候系统能量收支平衡、资料、模拟以及相关政策制定等方面带来的挑战,展望了未来的研究重点。     

非平稳时间序列的区域预测研究

基于重构状态空间理论和嵌入定理,给出一个新的非平稳场时间序列的区域预测方法。该方法将外强迫因子引入到预测模型中,并且将区域内预测相点的周围相点所对应的空间信息也引入到预测模型中。然后利用该方法对33模Lorenz系统得到的"理想"的非平稳场时间序列进行预测实验分析。结果表明,嵌入外强迫因子可以更好地重构出原来的动力系统,有效地提高非平稳时间序列的预测精度;同时引入空间和外强迫信息可以利用空间数据弥补时间序列长度的不足,从而进一步提高预测精度。     

A note on the economics of Swedish Baltic Sea fisheries

The cod stocks in the Baltic Sea are important not only for fisheries but for the entire ecosystem utilized by numerous stakeholders around the coast. All such activities have economic values. In this note the economics of the Swedish Baltic Sea cod fishery is estimated in relation to the sector's interaction with other users of the Baltic Sea ecosystem. The results show a negative resource rent for the fishery, € −5 million without public expenses (subsidies and administrative costs), and € −13 million including public expenses. The interactions between the fisheries and tourism, seal population, carbon dioxide emissions, recreational fishing, and discards are discussed, and when monetary estimates are available these are related to the estimated resource rent.     

An Ecosystem Based Fisheries Management framework: the efficient,regional-level planning tool for management agencies

The value of applying a regional level, Ecosystem Based Fisheries Management (EBFM) framework, which is a step-wise, hierarchical, risk-based approach, was tested on the West Coast Bioregion of Western Australia. With structured stakeholder input, over 600 ecological, social, economic and governance issues were initially identified for the region. This complexity was reduced to a level useful for management by consolidating the individual risks into 60 regional-level risks, with a multi-criteria analysis used to integrate the ecological, social and economic risks into just 24 Departmental-level priorities, which ranged from very low to urgent. Given this success, EBFM-based priorities now form the basis for the Department’s budget planning process, plus the framework is providing a critical link between fishery level issues and the broader processes undertaken by other marine based agencies. The EBFM framework is a significant step forward for the integrated management of natural resources by enabling all assets and issues relevant to stakeholders and government to be holistically considered at a regional level.     

Economic drivers of contemporary smallholder agriculture in a transitional economy: A case study of Hu Village from southwest China

Based on an in‐depth case study of a rural community, this paper documents the contemporary state of Chinese smallholder agriculture and the changes that it has been experiencing in the context of dramatic socio‐economic transition through the lens of three main economic drivers: livelihood diversification, market conditions and government interventions. Results reveal that the change in Chinese smallholder agriculture has been complex and multidimensional. All three factors exert profound influence and shape the current state of Chinese agriculture. Massive rural‐urban migration has resulted in labour shortages, which in turn have led to a reduction in agricultural diversity and land use intensity and a shift from traditional labour‐intensive technologies to modern capital‐intensive technologies. However, because of well‐developed agricultural markets, input use levels are similar across farmer categories (such as income diversification), helping to maintain productivity. Furthermore, reduced profits from farming due to increasing input prices and decreasing output prices have exerted pressure on smallholders to increasingly turn to nonfarm activities and have also triggered a thriving informal land transfer market, which was previously non‐existent. Policy implications include the need to strengthen local economies, improve market conditions, invest in rural infrastructures and facilitate smallholders' mobility.     

Rethinking corporate‐community engagement in the petro‐economy of the Niger Delta

This study applies the political ecology perspective in reframing corporate‐community engagement and adapts the community‐directed intervention (CDI) strategy using Global Memorandum of Understanding (GMoU) framework in relation to 30 rural communities that are likely to be affected by gas exploration and production activities in the Niger Delta region. The study draws attention to the indigenous structures and capacities of communities to implement CDI initiatives for possible replication in areas facing similar development challenges. Adopting the CDI framework as represented by the GMoU model could reconfigure social relations of power between companies and communities and fast‐track development and prevent or, at least, reduce corporate‐community tensions and conflicts in the petro‐economy of the Niger Delta.     

土质边坡震裂机制物理模拟研究

为了研究地震中土质边坡(包括覆盖层边坡)在强震作用下破裂的成因机制,以"5·12"汶川特大地震为背景资料,采用震动台模拟试验进行了研究.模拟试验结果表明:斜坡震裂变形破坏与斜坡外形结构特征具有相关性.坡面转折点应力最易集中,破坏的可能性较大.震动条件下土质边坡完全破坏也具有一般性的规律,即以"一垮到底"的方式堆积于坡脚...     

Up‐scaling potential impacts on water flows from agricultural water interventions: opportunities and trade‐offs in the Osman Sagar catchment,Musi sub‐basin,India

Agricultural water management (AWM) has been shown to improve and secure yields in the tropics and has been suggested as an important way to combat poverty in the region. In this paper, we describe potential impacts on upstream and downstream flows of extensive AWM interventions, using the watershed development programme of the Osman Sagar catchment of Musi sub‐basin, Andhra Pradesh semi‐arid India, as an example. Various AWM interventions are compared with a non‐intervention state and the current state of the study area, using 31 years of data by application of the calibrated and validated ARCSWAT 2005 (Version 2.1.4a) modelling tool. Different AWM interventions contribute to improved livelihoods of upstream smallholder farmers by increasing soil moisture availability and groundwater recharge, which can subsequently be used for irrigation. The result is higher crop production and hence larger incomes. Moreover, lower flow intensities and sediment losses reduced by 30–50%, reducing the risk of flooding and sediment accumulation in the Osman Sagar drinking water reservoir. On the other hand, AWM interventions are predicted to result in reduced total water inflows to the Osman Sagar reservoir from 11% of the total annual rainfall (754 mm) recorded at present, to 8% if AWM interventions were implemented at large scale throughout the catchment. A cost–benefit analysis of AWM interventions showed that the highest net economic returns were achieved at intermediate intervention levels (only in‐situ AWM). Copyright © 2012 John Wiley & Sons, Ltd.     

20世纪90年代末东亚冬季风年代际变化的外强迫因子分析

使用NCEP/NCAR、英国气象局哈德莱中心(Met Office Hadley Center)Had ISST以及NOAA提供的再分析资料分析了海温、海冰及雪盖异常对20世纪90年代末我国冬季气温和东亚冬季风(EAWM)年代际跃变的外部强迫作用,同时也对比分析了20世纪90年代EAWM年代际跃变与20世纪80年代EAWM年代际跃变特征和成因的一些差异。结果表明:20世纪80年代中期EAWM的年代际变化特征主要表现为全国一致偏冷型,同时中国近海的海温也偏低;该年代际变化的主要原因来自大气内部动力过程,而海温和海冰的作用不显著。20世纪90年代末EAWM年代际变化的特征表现为东亚北方气温显著偏冷而南方偏暖的南北反相变化分布;EAWM在20世纪90年代末的年代际变化受北大西洋海温和热带太平洋海温的共同影响。北大西洋显著的异常暖海温,激发一个向下游传播的波列,使得西伯利亚高压加强,EAWM加强,从而导致我国北方气温下降;同时,秋冬季北极海冰异常偏少和秋季欧亚雪盖偏多对东亚冬季风的增强也有一定的作用。此外,热带西太平洋的暖海温异常会导致在海洋性大陆地区有异常的辐合和对流增强,引起大气环流的Gill型响应,对流西侧的异常气旋在孟加拉湾至我国西南地区出现南风异常,使得东亚南部地区温度偏高。因此,20世纪90年代末之后东亚温度呈现南暖北冷的分布特征。     

Orogenic evolution of the External Dinarides in the NE Adriatic region: a model constrained by tectonostratigraphy of Upper Cretaceous to Paleogene carbonates

Mesozoic to Cenozoic evolution of the central part of the Adriatic plate (External Dinarides and Adriatic foreland) is still a matter of debate. This is expressed by opposing paleogeographic models: single carbonate platform (Adriatic or Adriatic-Dinaridic) versus two carbonate platforms (Adriatic and Dinaridic) separated by the inter-platform Budva-Cukali basin. Estimates of shortening during Adria NE subduction, that resulted in the development of the Dinaric Alps, differ substantially. The single-platform model involves minor shortening achieved by folding and faulting along steep reverse faults. The two-platform model involves significant shortening achieved mainly by thrust stacking, which resulted in almost complete underthrusting of the intervening basinal deposits.Analysis of Upper Cretaceous to Paleogene stratigraphical data from both outcrops and boreholes allows regional correlation and the interpretation of major lithostratigraphic units. As a result, a few tectonostratigraphic units are recognized. The tectonostratigraphy is used as a basis for a new model on the late Mesozoic to Cenozoic evolution of the region.Generally, Adriatic and Dinaridic segments acted as major regional crustal entities of Adria. The upper portions of the sedimentary cover were differentially affected by progressive, southwestward verging thin-skinned deformations during the Paleocene to Eocene (Miocene?). The Adriatic foreland stayed out of the deformations, and is characterized predominantly by wrench and salt tectonics. The regional tectonic map shows arcuate thrust fronts of the External Dinarides. They could be a consequence of both, differential propagation of early-orogenic thin-skinned deformations over crustal fragments separated by transversal faults, and/or differential (isostatic?) movements of the fragments. The collision zone of the Adriatic and Dinaridic segments is characterized by late-orogenic (Oligocene to Miocene) thick-skinned compressional uplift (exhumation), related gravity gliding, and still active escape tectonics (wrenching). These processes masked primary thin-skinned deformations. A significant amount of shortening within and between the thin-skinned sedimentary covers is proposed. Therefore, the question of the general paleogeography of the region and the original NW extent of the Budva-Cukali basin (NE Adriatic trough) remains open.