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61.
Climate engineering research attracts Slippery Slope concerns – the idea that initial research will inevitably lead to inappropriate deployment. Some have dismissed it as an unrealistic, unproductive critique. However, extant climate engineering discussions of the Slippery Slope discuss an unorganised set of different causal mechanisms with little detail. These range from technological cost reduction, to the creation of special interest lobby groups, to normalisation across society and policymakers. Dismissing the Slippery Slope may be premature if its causal nature is unclear, especially given the potentially high impacts and controversy of global climate engineering deployment. Disaggregating and clarifying the Slippery Slope can reduce unnecessary ambiguity, promote productive debate, and highlight risks that require further attention. Drawing on previous Slippery Slope literature and mechanisms of change from range of disciplines, this paper creates a typology of Slippery Slopes for application to stratospheric aerosol injection and other emerging technologies. Initial research can lead to deployment by 1) sparking price-performance improvements and sunk cost biases, 2) contributing to normalisation and legitimisation, 3) altering power structures, 4) sparking hype, and 5) incrementally progressing development. These feedback loops may currently seem unlikely, but unforeseen dynamics could still trigger rapid development and implementation of stratospheric aerosol injection. Conversely, there is no guarantee one of these Slippery Slopes will occur. The point is that they could – the future is too uncertain to fully dismiss non-linear change, particularly for high impact and accessible technologies like stratospheric aerosol injection. This can provide direction and clarity for effective technology governance and Slippery Slope discussion. Furthermore, this typology differentiates the Slippery Slope from lock-in and highlights their interaction points. Slippery Slope dynamics are processes that can (but are not guaranteed to) lead to different types of lock-in. Lock-in is when a technology is entrenched in existing sociotechnical systems. Given the risks of unchecked undesired lock-in, lock-in is a state to be encouraged instead of avoided.  相似文献   
62.
A programme of ground-based stratospheric and total NO2 column measurements was instituted at the Laboratory of Atmospheric Physics (40.5° N, 22.9° E) in August 1985. We present here the results of the first two years of measurements with a modified Canterbury filter photometer, details of which are given in the text. The stratospheric NO2 column, obtained at twilight during low local NO2 levels, shows the seasonal variation with monthly mean values of about 6×10-15 molec. cm-2 in the summertime to about 2.2×10-15 molec. cm-2 in the wintertime. These measurements compare well with measurements obtained with different instruments by other groups at similar latitudes (about 40° N) but in different places. Also, the asymmetry of the evening-to-morning stratospheric NO2 over Thessaloniki was found to be on the average equal to 1.58. Total NO2 column over Thessaloniki has a pronounced seasonal variation with amplitude of 0.68 matm. cm which can be explained partly from measured local NO2 sources which discharge in the mixing layer and partly from photolysis of the NO2 reservoir species.  相似文献   
63.
Analyses of evolutions of the kinetic and thermal energy associated with the major and minor stratospheric warmings in the winters of 1976–77 and 1975–76 respectively indicate that the predominant ultra-long waves in the stratosphere oscillated at periods of 10–20 days, whereas in the troposphere the predominant long waves oscillated at periods of 8 to 12 days. These tropospheric long waves are almost out-of-phase with the stratospheric ultra-long waves for the minor warming, but in-phase for the major warming. The kinetic energy of the zonal mean flow in the stratosphere for the minor warming is much greater than that for the major warming, indicating that the occurrence of a major warming depends on the magnitude of the kinetic energy of the zonal mean flow relative to that of the meridional convergence of the poleward flux of sensible heat. In both the major and minor warmings, most of the stratospheric eddy kinetic energy is contained in waves of wavenumbers 1 and 2, whereas the stratospheric available potential energy is primarily contained in waves of wavenumber 1. The kinetic energy associated with waves of wavenumber 1 appeared to be 180° out-of-phase with those of wavenumber 2, indicating that nonlinear transfer of kinetic energy occurred between waves of wavenumbers 1 and 2. The occurrences of wind reversals were accompanied by decouplings of the stratospheric and tropospheric motions, and blockings in the troposphere.  相似文献   
64.
Using satellite data, the variability of a large number of stratospheric trace constituents can be estimated. These constituents need not themselves be measured by the satellite; their concentrations can be derived using photochemical steady-state relationships. The global coverage provided by the satellite over a long time period means that, for example, monthly zonal mean profiles can be derived. This has been done for H, OH, HO2, H2O2, Cl, ClO, HCl, HOCl, ClONO2, NO and O. The standard deviation of these quantities is a measure of their variability. We argue that comparing theoretical variability estimates with measurements is a better test of a photochemical theory than simply the comparison of single modelled and observed profiles.  相似文献   
65.
1993年中国南极中山站(69°22'S,76°22'E)的一台波长为0.694μm的激光雷达对平流层进行了53次探测,从激光大气回波信号计算出平流层气溶胶后向散射比的垂直分布和12~30km高度范围内的积分后向散射系数。探测结果表明因受菲律宾Pinatubo火山爆发的影响,1993年南极地区平流层气溶胶粒子含量比1990年明显增加,证实了南极冬季平流层云的存在。平流层气溶胶为两层结构,12km附近高度上始终存在着一层厚度为数公里的气溶胶层,25km附近高度的一层变化较大。  相似文献   
66.
Discourse analyses and expert interviews about climate engineering (CE) report high levels of reflectivity about the technologies’ risks and challenges, implying that CE experts are unlikely to display moral hazard behaviour, i.e. a reduced focus on mitigation. This has, however, not been empirically tested. Within CE experts we distinguish between experts for radiation management (RM) and for carbon dioxide removal (CDR) and analyse whether RM and CDR experts display moral hazard behaviour. For RM experts, we furthermore look at whether they agree to laboratory and field research, and how they perceive the risks and benefits of one specific RM method, Stratospheric Aerosol Injection (SAI). Analyzing experts’ preferences for climate-policy options, we do not find a reduction of the mitigation budget, i.e. moral hazard, for RM or CDR experts compared to climate-change experts who are neither experts for RM nor for CDR. In particular, the budget shares earmarked for RM are low. The perceptions of risks and benefits of SAI are similar for RM and climate-change experts. Despite the difference in knowledge and expertise, experts and laypersons share an understanding of the benefits, while their perceptions of the risks differ: experts perceive the risks to be larger.

Key policy insights

  • Experts surveyed all prioritize mitigation over carbon dioxide removal and in particular radiation management.

  • In the views of the experts, SAI is not a viable climate policy option within the next 25 years, and potentially beyond, as global field-testing (which would be a precondition for long-term deployment) is widely rejected.

  • In the case of SAI, greater knowledge leads to increased awareness of the uncertainty and complexity involved. Policy-makers need to be aware of this relationship and the potential misconceptions among laypersons with limited knowledge, and should follow the guidelines about communicating risks and uncertainties of CE that experts have been advised to follow.

  相似文献   
67.
中国平流层CH4的分布特征和季节变化   总被引:8,自引:5,他引:3  
郑彬  施春华  陈月娟 《高原气象》2006,25(4):609-615
利用UARS卫星上HALOE试验的1992—2003年CH4资料,分析了中国平流层的CH4混合比分布特征,并对CH4混合比在不同纬度上的季节变化作了详细分析。结果表明,中国平流层CH4混合比随着高度逐渐减小,在经向上有较大差异,总是南边大于北边,而各个纬度带上的分布则较均匀。分析结果还表明,中国平流层CH4混合比在DJF的季节距平与MAM有相反的符号,而且中心位置基本吻合。此外,季节变率最大的是MAM—DJF,而不是JJA—DJF。并且在平流层低层的夏半年有明显的高值带,这可能与上升运动和辐散辐合作用有关。  相似文献   
68.
为提高复杂地理环境和极端天气条件下的大气廓线探测能力,本文自主研发了基于平流层高空气球平台的下投探空系统,并在青藏高原开展探测评估实验.该系统主要由下投探空舱,携带降落伞的下投探空仪,下投施放装置,数据接收通讯天线和GPS模块等组成.下投探空仪测量数据通过卫星通信链路和无线电信号实时发送至数据接收机存储处理.2020年...  相似文献   
69.
平流层爆发性增温中平流层环流及化学成分变化过程研究   总被引:3,自引:1,他引:2  
利用欧洲中期天气预报中心(ECMWF)气象分析场、欧洲空间局ENVISAT/MIPAS卫星观测资料以及平/对流层大气化学输送模式MOZART 3综合分析了2003—2004年冬季北半球爆发性增温事件对于平流层大气环流、物质输送以及对流层顶附近臭氧通量等多方面的影响。结果表明:①本次增温过程持续时间长、强度大,平流层极涡从高层向下逐层分裂,增温效应作用到大气较低层,当纬向东风形成并维持后极涡又自上向下逐层恢复;②SSW过程前后行星波活动频繁,有长时间多次的上传,且以1波作用为主,2波对其进行补充;③在θ PVLAT坐标中分析发现SSW扰动过程中平流层中存在一对向极、向下的传播模态,相应的对流层中有一向赤道的传播模态,不同符号的纬向风、温度异常信号沿这两个模态传播,且上、下层传播模态在时间上存在着一定的联系;④增温过程中行星波活动引起的向极输送以及极区垂直运动的变化,共同影响了平流层的物质输送过程,从而导致北半球平流层N2O、O3、CH4、H2O等微量气体成分的垂直、水平分布发生显著变化;⑤增温过程中活跃的行星波可以造成平流层Brewer Dobson环流增强,同时导致高纬度地区(60~90°N)穿越对流层顶的臭氧通量(Cross Tropopause Ozone Flux, CTOF)显著增强,与行星波相联系的等熵物质运动引起“middleworld”区域内向赤道的臭氧通量也有所增强。  相似文献   
70.
马骥  陈文  兰晓青 《大气科学》2020,44(4):726-747
利用1958~2017年逐日的NCEP/NCAR再分析资料对北半球冬季平流层强、弱极涡事件的演变过程进行了对比分析,同时比较了有平流层爆发性增温(SSW)和无SSW发生的两类弱极涡事件的环流演变和动力学特征。结果表明,强极涡的形成存在着缓慢发展和快速增强的过程,而弱极涡事件的建立非常迅速;和强极涡事件相比,弱极涡事件的峰值强度更强,异常中心的位置更高。此外,强、弱极涡事件的产生与波流相互作用的正反馈过程密切相关。对于强极涡事件,发展阶段的太平洋—北美(PNA)型异常削弱了行星波一波;当平流层西风达到一定强度,上传的行星波受到强烈抑制,使得极涡迅速增强达到峰值。而对于弱极涡事件,发展阶段一波型的异常增强了行星波上传,通过对纬向流的拖曳作用使得平流层很快处于弱西风状态,更多行星波进入平流层导致极涡急剧减弱甚至崩溃。针对有、无SSW发生的两类弱极涡事件的对比分析表明,有SSW发生的弱极涡事件发展阶段,平流层出现强的向上的一波Eliassen-Palm(EP)通量异常,通过正反馈过程使得一波和二波上传同时增强而导致极涡崩溃;无SSW发生的弱极涡事件发展阶段,平流层缺乏向上的一波通量,二波活动起到重要作用,其总的行星波上传远弱于有SSW发生的弱极涡事件。对于无SSW发生的弱极涡事件,其发展和成熟阶段对流层上部出现类似欧亚(EU)型的高度异常,伴随着强的向极的EP通量异常,导致对流层有极强的负北极涛动(AO)型异常。而有SSW发生的弱极涡事件发展阶段对流层上部主要表现为北太平洋上空来自低纬的波列异常,其后期的对流层效应更加滞后也不连续,对流层AO异常的强度明显弱于无SSW发生的弱极涡事件。  相似文献   
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