INTEX-B NO2排放源在中国地区的应用与检验

将INTEX-B排放源应用到空气质量模型Model3-CMAQ中,对中国地区对流层NO₂的浓度分布进行了数值模拟,并与OMI卫星对流层NO₂资料进行了对比和验证。结果表明：将INTEX-B排放源应用到Model3-CMAQ模式,模拟的NO₂浓度在中国地区的分布、季节变化规律与卫星资料所得结果一致。敏感性试验表明,工业及电厂排放对NO₂的浓度贡献最大,而交通排放的贡献相对较小,两种排放均主要集中在京津、长江三角洲等经济发达地区。     

The Green''''s function of the harmonic horizontal force applied at the interior of the saturated half-space soil

IntroductionThe wave propagation problems in saturated soil are very important for the civil engineering, geophysics and seismology. Biot (1956,1962) established the theory of wave propagation in saturated soil firstly, and hereafter many researchers have used Biot theory to study wave propagation problems in saturated soil. By using integral transform and potential function method, Philippacopoulos (1988) studied the Lamb(s problem of a vertical point force applied to the surface of saturate…     

预修正快速傅里叶变换高阶边界元方法在波浪对物体作用问题中的应用

边界元方法被广泛应用于波浪对海上婕筑物作用领域,但由于传统边界元方法的存储量和计算量均为未知量的平方量级,很难满足大范围多未知量问题的计算需要.本文基于高阶边界元方法,应用预修正快速傅里叶变换方法,使计算量与存储量分别降低至O(NlogN)和O(N)量级,并得到一个连续的压强分布以适应结构设计的要求,同时可以通过使用满...     

梭梭荒漠生态系统：Ⅰ初级生产力及其群落结构的动态变化

通过对梭梭荒漠群落的种类组成、垂直结构、水平结构、季相及梭梭当年生绿色同化枝和草本层的地上植物量的研究，表明在以小半乔木梭梭占主导地位的群落中，丰富的短生植物及长营养期一年生植物均得到较好的发育，说明该群落具有由中亚荒漠向亚洲中部荒漠过渡的性质。而大量单种属或寡种属出现，反映出了梭梭群落具有干旱植物区系的明显特征，与整个新疆植被荒漠植物区系的特征相一致。梭梭群落中建群层片的种类单一，与北疆其它荒漠植被类型相似，而伴生植物的种类组成比其它类型丰富，特别是短生植物及长营养期一年生植物种类较多。初级生产力分别与梭梭当年生绿色同化枝的萌发、生长和脱落，短生植物的迅速生长和死亡，以及长营养期一年生植物的生长有密切关系，分别在５月下旬、６月下旬和８月上旬达到高峰。梭梭当年生绿色同化枝的植物量在其整个群落初级生产力的构成中作用明显。是整个群落初级生产力的７２．３％～８５．８％。     

Latitudinal and Scan-dependent Biases of Microwave Humidity Sounder Measurements and Their Dependences on Cloud Ice Water Path

The relationship between differences in microwave humidity sounder(MHS)–channel biases which represent measured brightness temperatures and model-simulated brightness temperatures, and cloud ice water path(IWP) as well as the influence of the cloud liquid water path(LWP) on the relationship is examined. Seven years(2011–17) of NOAA-18 MHS-derived measured brightness temperatures and IWP/LWP data generated by the NOAA Comprehensive Large Array-data Stewardship System Microwave Surface and Precipitation Products System are used. The Community Radiative Transfer Model, version2.2.4, is used to simulate model-simulated brightness temperatures using European Center for Medium-Range Weather Forecasts reanalysis data as background fields. Scan-angle deviations of the MHS window channel biases range from-1.7 K to1.0 K. The relationships between channels 2, 4, and 5 biases and scan angle are symmetrical about the nadir. The latitudedependent deviations of MHS window channel biases are positive and range from 0–7 K. For MHS non-window channels,the latitudinal deviations between measured brightness temperatures and model-simulated brightness temperatures are larger when the detection height is higher. No systematic warm or cold deviations are found in the global spatial distribution of difference between measured brightness temperatures and model-simulated brightness temperatures over oceans after removing scan-angle and latitudinal deviations. The corrected biases of five different MHS channels decrease differently with respect to the increase in IWP. This decrease is stronger when LWP values are higher.     

Cleantech clusters: Transformational assemblages for a just,green economy or just business as usual?

The rhetorical zeal for green enterprise as a global fix for the tripartite challenges of economic recession, environmental degradation and social inequality is increasingly visible in state and non-state pronouncements around the globe under the banner of ‘The Green Economy’. In particular, many policy-facing statements call for transitions leading to a transformation in development practices. Yet there is little detail either in policy or research regarding the types of transitions needed and how they are to be initiated, nor agreement about what a transformed economy might look like. Despite this, there are emergent activities within the cleantech arena which are being heralded as actually existing examples of green economy activities. One means through which these activities are seeking to exert influence over development trajectories is by clustering both at the subnational and transnational level. While diverse in formation, many of these clusters are hybridised, involving actors from public, private and civil society sectors. Critiquing the efficacy of mainstream industrial cluster theory to analyse hybridised cleantech clustering, this paper presents a unique synthesis of current thought on multiscalar environmental governance and socio-spatial formations to explore the practices and potentialities of these hybridised cleantech clusters. Surveying the landscape of cleantech clustering and meta-clustering, before focusing in depth on one case study, the contribution of clustering to transitioning towards a transformed green economy is considered. Despite strong forces, both within and beyond cleantech clusters, for maintaining neoliberalised approaches to cleantech activity, it is concluded that for as long as cleantech clusters remain open and inclusive of actors proposing alternative pathways they do represent potential, albeit provisional, assemblages for transformation.     

Land tenure and REDD+: The good,the bad and the ugly

A number of international donors, national governments and project proponents have begun to lay the groundwork for REDD+, but tenure insecurity – including the potential risks of land grabbing by outsiders and loss of local user rights to forests and forest land – is one of the main reasons that many indigenous and other local peoples have publicly opposed it. Under what conditions is REDD+ a threat to local rights, and under what conditions does it present an opportunity? This article explores these issues based on available data from a global comparative study on REDD+, led by the Center for International Forestry Research, which is studying national policies and processes in 12 countries and 23 REDD+ projects in 6 countries. The article analyses how tenure concerns are being addressed at both national and project level in emerging REDD+ programs. The findings suggest that in most cases REDD+ has clearly provided some new opportunities for securing local tenure rights, but that piecemeal interventions by project proponents at the local level are insufficient in the absence of broader, national programs for land tenure reform. The potential for substantial changes in the status quo appear unlikely, though Brazil – the only one with such a national land tenure reform program – offers useful insights. Land tenure reform – the recognition of customary rights in particular – and a serious commitment to REDD+ both challenge the deep-rooted economic and political interests of ‘business as usual’.     

Social capital and community preparation for urban flooding in China

Social capital can enhance community resilience to environmental change. Productive and trusted relations among social actors and effectual social norms can help local residents share resources, information and risks. The main objective of our study is to understand the ways in which social attributes and risk considerations influence adoption of resilient economic measures by individuals for reducing potential losses due to catastrophic rainstorm and flooding. This article provides evidence from China on how social capital contributes to anticipatory adaptation to environmental change. The inquiry is based on structured interviews with local residents of Tianjin, a flood-prone port city in China, and a standard regression analysis. Findings show that the intention to make preparation increases with the levels of social expectation, social relationship, and institutional trust. Perceived risk and damage experience, however, have no significant impacts. This suggests that building social capacity and trust will be more effective in enhancing community resilience than merely increasing awareness of hazard risks. We call for greater efforts on strengthening the capacity of formal and informal communal institutions. The structural changes required, however, are challenging.     

Modeling Study of the Effect of Anthropogenic Aerosols on Late Spring Drought in South China

In this study,the mechanisms underlying the decadal variability of late spring precipitation in South China are investigated by using the latest Community Earth System Model version 1 （CESM1）.We aim to unravel the effects of different climate forcing agents such as aerosols and greenhouse gases （GHGs） on the decadal variation of precipitation,based on transient experiments from pre-industry （for year 1850） to present-day （for year 2000）.Our results reveal that：（1） CESM1 can reproduce the climatological features of atmospheric circulation and precipitation for the late spring in South China; （2） only simulations including the forcing of anthropogenic aerosols can reproduce the observed decreasing trend of late spring precipitation from 1950-2000 in South China; （3） aerosols affect the decadal change of precipitation mainly by altering the large-scale atmospheric circulation,and to a less extent by increasing the lower-tropospheric stability to inhibit the convective precipitation; and （4） in comparison,other climate forcing agents such as GHGs have much smaller effects on the decadal change of spring precipitation in South China.     

多尺度非静力通用模式框架的设计策略

针对目前国际上数值预报模式的最新发展趋势,综述了新形势下多尺度非静力通用数值预报模式框架的设计策略。目前世界上开发通用模式主要有两个途经,一是建立一个离散化方案和源程序代码共享的、全球和有限区通用的模式,二是建立一个单一的全球可变分辨率的模式。还从通用模式方程组的选取策略、模式网格属性的构造,时间积分方案、空间离散方案,垂直坐标的选取等方面进行了分析。