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1.
Results of a single group participating in an international experiment are analyzed. The experiment served to verify computational predictions of the ground-motion variations due to near-surface geological effects at a site established for that purpose by the California Department of Conservation. Based on an acceleration record at a rock location, and geotechnical model of medium, records at the other locations of a nearby sedimentary deposit were predicted. A 2-D finite-difference sensitivity analysis suggested that the lateral wave-propagation effects are negligibly small, and locally 1-D computations are sufficient for the present site. Those computations are compared with observations not available to the authors during the blind prediction. Peak accelerations, peak velocities and RMS accelerations were predicted with errors less than 159%, 114% and 62%, respectively. Maxima of the response spectra were fitted within a factor of 2. The predicted and observed Husid's plots (i.e., the normalized cumulative plots of the acceleration squared) have the correlation coefficients 0.98. The detected misfits do not show any simple relation to the instrument location, component, frequency, or time. 相似文献
2.
Frank Peeters Urs Beyerle Matthias S. Brennwald 《Geochimica et cosmochimica acta》2004,68(6):1437-1438
3.
This article argues that the material incentives associated with climate policies such as the Clean Development Mechanism (CDM) may contribute to the socialization of emerging economies such as Vietnam in economic-oriented climate change norms. In current academic research, the CDM has both been extolled as a cost-effective and vilified as an environmentally inadequate instrument. Few studies so far, however, have looked into the CDM's potential contribution to socialization-related phenomena such as raising climate change awareness. This article aims to fill that gap by studying the CDM in EU–Vietnam relations in four periods, namely initiation (2001–2007), improvement (2008–2010), consolidation (2010–2012), and potential habit formation (2012 and beyond), with both the EU and Vietnam being important players in the market for CDM credits (Certified Emission Reductions or CERs). We argue that there is at least a strong potential for habit formation resulting from the CDM's material incentives, and that the underlying causal mechanism involves the emergence and activities of norm entrepreneurs and habit formation through a process of legal institutionalization.Policy relevanceNormative transformation or change is increasingly attracting the attention of both climate policy makers and scholars alike, certainly in view of the failures of ‘standard’ economic or technological solutions to tackle climate change. There is a need, however, to apply insights from social theory to specific policies and cases. The policy relevance of this article lies here: does the CDM (a specific policy) affect climate concerns (norms) in Vietnam (a specific case)? And, if so, to what extent and why? Based on previous research regarding the Chinese case, it is expected that the CDM's material incentives result in a mild effect in Vietnam, probably less pronounced than in China in view of the latter's relative level of economic development, and the strength of its political and legal-institutional system and (human) capacity to develop CDM projects. This article's research findings point out that whether and how ‘deep’ these new shared ideas will succeed in becoming standards of appropriate behaviour in Vietnam might to some extent depend on whether the international community is able to offer a material incentive structure that fosters such a normative transformation. 相似文献
4.
5.
Alan D. Ziegler Edwin P. Maurer Justin Sheffield Bart Nijssen Eric F. Wood Dennis P. Lettenmaier 《Climatic change》2005,72(1-2):17-36
We use diagnostic studies of off-line variable infiltration capacity (VIC) model simulations of terrestrial water budgets
and 21st-century climate change simulations using the parallel climate model (PCM) to estimate the time required to detect
predicted changes in annual precipitation (P), evapotranspiration (E), and discharge (Q) in three sub-basins of the Mississippi River Basin. Time series lengths on the order of 50–350 years are required to detect
plausible P, E, and Q trends in the Missouri, Ohio, and Upper Mississippi River basins. Approximately 80–160, 50, and 140–350 years, respectively,
are needed to detect the predicted P, E, and Q trends with a high degree of statistical confidence. These detection time estimates are based on conservative statistical
criteria (α = 0.05 and β = 0.10) associated with low probability of both detecting a trend when it is not occurring (Type
I error) and not detecting a trend when it is occurring (Type II error). The long detection times suggest that global-warming-induced
changes in annual basin-wide hydro-climatic variables that may already be occurring in the three basins probably cannot yet
be detected at this level of confidence. Furthermore, changes for some variables that may occur within the 21st century might
not be detectable for many decades or until the following century – this may or may not be the case for individual recording
station data. The long detection times for streamflow result from comparatively low signal-to-noise ratios in the annual time
series. Finally, initial estimates suggest that faster detection of acceleration in the hydrological cycle may be possible
using seasonal time series of appropriate hydro-climatic variables, rather than annual time series. 相似文献
6.
Bart E. van Dongen Andrew P. Roberts Wei-Teh Jiang Richard D. Pancost 《Geochimica et cosmochimica acta》2007,71(21):5155-5167
The biomarker compositions of iron sulfide nodules (ISNs; upper Pliocene Valle Ricca section near Rome, Italy) that contain the ferrimagnetic mineral greigite (Fe3S4) were examined. In addition to the presence of specific terrestrial and marine biomarkers, consistent with formation in coastal marine sediments, these ISNs contain compounds thought to originate from sulfate reducing bacteria (SRB). These compounds include a variety of low-molecular-weight and branched alkanols and several non-isoprenoidal dialkyl glycerol diethers (DGDs). In addition, archaeal biomarkers, including archaeol, macrocyclic isoprenoidal DGDs and isoprenoidal glycerol dialkyl glycerol tetraethers are also present. Both SRB and archaeal lipid δ13C values are depleted in 13C (δ13C values are typically less than −50‰), which suggests that the SRB and archaea consumed 13C depleted methane. These biomarker and isotopic signatures are similar to those found in cold seeps and marine sediments where anaerobic oxidation of methane (AOM) occurs with sulfate serving as the terminal electron acceptor. Association of AOM with formation of greigite-containing ISNs could provide an explanation for documented remagnetization of the Valle Ricca sediments. Upward migration of methane, subsequent AOM and associated authigenic greigite formation are widespread processes in the geological record that have considerable potential to compromise paleomagnetic records. 相似文献
7.
Gerhard Bart Mohammed Ikramuddin Michael E. Lipschutz 《Geochimica et cosmochimica acta》1980,44(5):719-730
We report data for Ag, Bi, Cd, Co, Cs, Ga, In, Se, Te, Tl and Zn determined by neutron activation in Allende samples heated for one week at 100° increments in the 1000–1400°C range in a low pressure (initially 10?5atmH2) environment using an apparatus of novel design. In the extremes, concentrations of these trace elements—initially present at ppm-ppb levels—in unheated material are lowered even farther by factors of 10?4–10?5 over a broad temperature span. Loss of some elements above 1000°C extends trends evident below 1000°C; loss of others is even more extreme. On Arrhenius diagrams some elements exhibit but one apparent activation energy over the entire temperature span of loss while others exhibit 2 or 3, each operative in a particular temperature region. These discontinuities seem related to mineralogic/petrologic alteration and probably reflect differences in diffusion mechanism rather than siting differences. The extension of previous experiments into the temperature regime postulated for chondritic differentiation should lead to a better understanding of the evolution of meteoritic parent bodies. 相似文献
8.
Instrumental neutron activation analysis was used for the determination of more than 20 trace and minor elements in water and silt samples (suspended load) of the river Aare. The samples were collected at four different locations along the river between its source and the lake of Bienne. The principal results are: 1. The concentrations of all elements investigated are much lower than WHO-limits for drinking water. 2. Human activities are responsible for an increase of some elements along the river. 3. The concentrations of dissolved trace elements are generally anticorrelated with the water flow rate. 4. The concentrations of the trace elements in particulates (in μg/l) are correlated with the flow rate of water. Except for Ca?Sr there are no significant interelement correlations for all four sampling stations. 相似文献
9.
In an attempt to discriminate between tectonically induced sea-level changes and glacio-eustacy, the Ekklissia and Arakthos sections (Epirus, NW Greece) are examined, applying (dinocyst) palynology, sedimentology and magnetostratigraphy. The sections, located in the Pindos Foreland Basin, both comprise the transition from pelagic limestones to hemipelagic silty clays and turbidite sandstones, reflecting the onset of flysch sedimentation as a result of the Pindos thrust activity. Despite an overall tectonic overprint, relative changes of sea level can be reconstructed, using (i) continental/marine palynomorph ratios, (ii) relative abundance of inshore and offshore dinoflagellate cysts, and (iii) taxa indicative of relatively cold and warm sea-surface temperature, that can be calibrated against the Global Polarity Time Scale (GPTS). Increased fluxes of marginal marine and continental palynomorphs coincide with colder periods on a 'third-order' scale, which thus appear to be related to glacio-eustatic trends in sea-level. The larger scale is attributed to the increasing effect of tectonics and acts on a 'second-order scale'. 相似文献
10.
The radiation chemistry, thermal stability, and vapor pressure of solid-phase carbonic acid (H2CO3) have been studied with mid-infrared spectroscopy. A new procedure for measuring this molecule’s radiation stability has been used to obtain intrinsic IR band strengths and half-lives for radiolytic destruction. We report, for the first time, measurements of carbonic acid’s vapor pressure (0.290-2.33 × 10−11 bar for 240-255 K) and its enthalpy of sublimation (71 ± 9 kJ mol−1). We also report the first observation of a chemical reaction involving solid-phase carbonic acid. Possible applications of these findings are discussed, with an emphasis on the outer Solar System icy surfaces. 相似文献