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91.
Governance,complexity, and resilience 总被引:1,自引:0,他引:1
Andreas Duit Victor Galaz Katarina Eckerberg Jonas Ebbesson 《Global Environmental Change》2010,20(3):363-368
This special issue brings together prominent scholars to explore novel multilevel governance challenges posed by the behavior of dynamic and complex social-ecological systems. Here we expand and investigate the emerging notion of “resilience” as a perspective for understanding how societies can cope with, and develop from, disturbances and change. As the contributions to the special issue illustrate, resilience thinking in its current form contains substantial normative and conceptual difficulties for the analysis of social systems. However, a resilience approach to governance issues also shows a great deal of promise as it enables a more refined understanding of the dynamics of rapid, interlinked and multiscale change. This potential should not be underestimated as institutions and decision-makers try to deal with converging trends of global interconnectedness and increasing pressure on social-ecological systems. 相似文献
92.
Silja Märdla Jonas Ågren Gabriel Strykowski Tõnis Oja Artu Ellmann René Forsberg 《Marine Geodesy》2017,40(6):416-453
The deduction of a regularly spaced gravity anomaly grid from scattered survey data is studied, addressing mainly two aspects: reduction of gravity to anomalies and subsequent interpolation by various methods. The problem is illustrated in a heterogeneous study area and contrasting test areas including mountains, low terrains, and a marine area. Provided with realistic error estimates, Least Squares Collocation interpolation of Residual Terrain Model anomalies yields the highest quality gravity grid. In most cases, the Bouguer reduction and other interpolation methods tested are equally viable. However, spline-based interpolation should be avoided in marine areas with trackwise survey data. 相似文献
93.
Mauricio Jonas Ferreira Amauri Pereira de Oliveira Jacyra Soares Georgia Codato Eduardo Wilde Bárbaro Jo?o Francisco Escobedo 《Theoretical and Applied Climatology》2012,107(1-2):229-246
The main goal of this work is to describe the diurnal and seasonal variations of the radiation balance components at the surface in the city of S?o Paulo based on observations carried out during 2004. Monthly average hourly values indicate that the amplitudes of the diurnal cycles of net radiation (Q*), downwelling and upwelling shortwave radiation (SWDW, SWUP), and longwave radiations (LWDW, LWUP) in February were, respectively, 37%, 14%, 19%, 11%, and 5% larger than they were in August. The monthly average daily values indicate a variation of 60% for Q*, with a minimum in June and a maximum in December; 45% for SWDW, with a minimum in May and a maximum in September; 50% for SWUP, with a minimum in June and a maximum in September; 13% for LWDW, with a minimum in July and a maximum in January; and 9% for LWUP, with a minimum in July and a maximum in February. It was verified that the atmospheric broadband transmissivity varied from 0.36 to 0.57; the effective albedo of the surface varied from 0.08 to 0.10; and the atmospheric effective emissivity varied from 0.79 to 0.92. The surface effective emissivity remained approximately constant and equal to 0.96. The albedo and surface effective emissivity for S?o Paulo agreed with those reported for urban areas in Europe and North America cities. This indicates that material and geometric effects on albedo and surface emissivity in S?o Paulo are similar to ones observed in typical middle latitudes cities. On the other hand, it was found that S?o Paulo city induces an urban heat island with daytime maximum intensity varying from 2.6°C in July (16:00 LT) to 5.5°C in September (15:00 LT). The analysis of the radiometric properties carried out here indicate that this daytime maximum is a primary response to the seasonal variation of daily values of net solar radiation at the surface. 相似文献
94.
A method is introduced for assessing the probabilities and intensities of tropical cyclones at landfall and applied to data
from the North Atlantic. First, a recently developed model for the basin-wide Monte-Carlo simulation of tropical cyclone tracks
is enhanced and transferred to the North Atlantic basin. Subsequently, a large number of synthetic tracks is generated by
means of an implementation of this model. This synthetic data is far more comprehensive than the available historical data,
while exhibiting the same basic characteristics. It, thus, creates a more sound basis for assessing landfall probabilities
than previously available, especially in areas with a low historical landfall frequency. 相似文献
95.
96.
Jonathan S. Friedman Craig A. Tepley Shikha Raizada Qihou H. Zhou Jonas Hedin Rubn Delgado 《Journal of Atmospheric and Solar》2003,65(16-18):1411-1424
We have developed a lidar to study the temperature structure of the nighttime mesopause region over the Arecibo Observatory (18.35°N, 66.75°W) by measuring the lineshape of the fluorescence spectrum of atomic potassium that is deposited in the mesosphere and lower thermosphere (MLT) by meteors. To demonstrate how the potassium lidar can enhance MLT studies at Arecibo, we show recent results for: (1) comparisons with airglow temperature measurements; (2) simultaneous operations with stratospheric and mesospheric temperature profiling by Rayleigh lidar; (3) simultaneous observations of K, Ca+, and E-region electron density profiles; and (4) occurrences of sporadic K layers, and relationships to sporadic E layers. 相似文献
97.
夏季自然水体与大气界面间气态总汞的交换通量 总被引:10,自引:0,他引:10
利用动力学通量箱法与高时间分辨率大气测汞仪的联用技术, 在瑞典西南的Kristineberg海洋观测站(KMRS)和Knobesholm的Hovgårdsån河分别测定了夏季海水和河水表面与大气间汞的交换通量. 在夏季, 河水和海水都是大气汞的源. 河水和海水表面与大气间汞的交换通量在夏季具有一致的昼夜变化规律, 白天由水体向大气排汞且在正午达到最大值; 夜间排汞量相对较小且有时会出现大气汞向水体沉降. 河水与大气间汞的交换通量与光照强度呈线性正相关关系, 与大气相对湿度呈线性负相关性, 同时还与水体温度存在指数相关性. 海水与大气间汞交换通量只与光照强度存在良好的线性正相关关系. 水体中溶解态气汞的过饱和是水体汞向大气释放的驱动力. 相似文献
98.
In search for a suitable and fast analytical method for assessing kinds of activated carbon for water purification there were carried out investigations with hydrogen peroxide. According to their catalytic activity, the various kinds of activated carbon are capable of decomposing hydrogen peroxide to different degrees and at different rates. The released oxygen can be determined volumetrically. The results of investigation obtained on always fresh carbon samples with acid and basic groups were discussed on the basis of the velocity constants of the oxygen development. An assessment of quality would be possible, in principle, but the surface characteristic of the kinds of carbon is considerably superimposed by influences of morphology, so that applying this method is advised against. 相似文献
99.
Jonas Koko 《Computational Geosciences》2007,11(4):307-317
We present two Lagrange multiplier-based domain decomposition methods for solving iteratively a non-linear sedimentary basin
problem. Both methods are Uzawa-type algorithms derived from saddle point equations of Lagrangian and augmented Lagrangian
functionals. Numerical experiments show that both methods are scalable with respect to the mesh size. 相似文献
100.
An ensemble of seven climate models from the North American Regional Climate Change Assessment Program (NARCCAP) was used to examine uncertainty in simulated runoff changes from a base period (1971–2000) to a future period (2041–2070) for the Churchill River basin, Labrador, Canada. Three approximations for mean annual runoff from each ensemble member were included in the analysis: (i) atmospheric moisture convergence, (ii) the balance between precipitation and evaporation, and (iii) instantaneous runoff output from respective land-surface schemes. Using data imputation (i.e., reconstruction) and variance decomposition it was found that choice of regional climate model (RCM) made the greatest contribution to uncertainty in the climate change signal, whereas the boundary forcing of a general circulation model (GCM) played a smaller, though non-negligible, role. It was also found that choice of runoff approximation made a substantial contribution to uncertainty, falling between the contribution from RCM and GCM choice. The NARCCAP output and imputed data were used to calculate mean and median annual changes and results were presented via probability distribution functions to facilitate decision making. Mean and median increases in runoff for the basin were found to be 11.2% and 8.9%, respectively. 相似文献