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101.
This paper assesses regional abatement action and costs for two scenarios in which atmospheric greenhouse gas concentrations
stabilise at 450 and 550 ppm CO2-equivalent. It evaluates two allocation schemes: Multi-Stage and Contraction & Convergence. It was found that abatement costs
as percentages of GDP vary significantly by region, with high costs for the Middle East and the former Soviet Union, medium
costs for the OECD regions and low costs or even gains for (other) developing regions. In addition to the abatement costs
they incur, fossil-fuel-exporting regions are also likely to be affected by losses of coal and oil exports while the former
Soviet Union and South America could experience increased bio-energy exports. Especially in the former Soviet Union and Asia,
non-CO2 abatement options are important in the short term in reducing their emissions. Carbon capture and storage, energy efficiency
improvements, bio-energy use and the use of renewables dominate reductions in the long term in all regions. It was found that
the regional costs are influenced more by the assumed stabilisation level and baseline scenario than by the allocation regimes
explored or the assumptions for different technologies. 相似文献
102.
Zur Gefügeregelung von Olivin-Porphyroblasten im Ultramafiti-Komplex von Åheim,Sunnmöre/Westnorwegen
Zusammenfassung Die Gefügeregelung von Olivin-Porphyroblasten in dunitischen Ultramafititen des Åheimer Komplexes ist durch eine bevorzugteZ-Orientierung parallel zur Lineation-entsprechend der tektonischen B-Achse-gekennzeichnet.X undY liegen mit diskreten Maxima auf einem ac-Gürtel. Die Orientierung der Porphyroblasten entspricht einem reliktisch erhaltenen, älteren Verformungsplan, dessenPT-Bedingungen aus experimentellen Ergebnissen anderer Autoren und mit genetischer Parallelisierung zur Bildung der Granatultramafitite des Gebietes erklärt werden können.Kleine, rekristallisierte Olivinkorn-Einschlüsse in den Porphyroblasten zeigen einen Trend zu einerX-Orientierung senkrecht auf s;Y rotiert dabei in die Richtung der Gesteinslineation. Diese Orientierung ist in vielen, während einer jüngeren, retrograden Metamorphose rekristallisierten Olivingesteinen beobachtbar, welche unter denPT-Bedingungen einer Chlorit-Hornblende-Peridotitfazies stattfand.
Mit 6 Abbildungen
Herrn Prof. Dr. Dr. h. c.B. Sander zum 90. Geburtstag gewidmet. 相似文献
Fabric orientation of olivine porphyroblasts in the Ultramafitite Complex of Åheim, Sunnmöre, western Norway
Summary The lattice orientation of olivine porphyroblasts in dunites of the Åheim Ultramafic Complex, western Norway, shows a principal -direction parallel to lineation in the host rock, corresponding to the tectonic B-axis. The other optical axes and form a girdle in the tectonic ac-plane with certain maximas. This orientation is caused by an earlier stress pattern. ThePT-conditions of this deformation may be explained by experimental results of other authors.Small recrystallized olivine inclusions in the blasts tend toward an -orientation perpendicular to S; rotates into the direction of lineartion. The same orientation occurs predominatly in the olivine rocks of the complex, which also have recrystallized during a younger retrograde metamorphism under the conditions of the chlorite amphibole peridotite facies.
Mit 6 Abbildungen
Herrn Prof. Dr. Dr. h. c.B. Sander zum 90. Geburtstag gewidmet. 相似文献
103.
Determination of Forty Two Major and Trace Elements in USGS and NIST SRM Glasses by Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry 总被引:39,自引:0,他引:39
Shan Gao Xiaomin Liu Honglin Yuan Bodo Hattendorf Detlef Günther Liang Chen Shenhong Hu 《Geostandards and Geoanalytical Research》2002,26(2):181-196
Forty two major (Na, Mg, Ti and Mn) and trace elements covering the mass range from Li to U in three USGS basalt glass reference materials BCR‐2G, BHVO‐2G and BIR‐1G were determined using laser ablation‐inductively coupled plasma‐mass spectrometry. Calibration was performed using NIST SRM 610 in conjunction with internal standardisation using Ca. Determinations were also made on NIST SRM 612 and 614 as well as NIST SRM 610 as unknown samples, and included forty five major (Al and Na) and trace elements. Relative standard deviation (RSD) of determinations was below 10% for most elements in all the glasses under investigation. Consistent exceptions were Sn and Sb in BCR‐2G, BHVO‐2G and BIR‐1G. For BCR‐2G, BHVO‐2G and BIR‐1G, clear negative correlations on a logarithmic scale exist between RSD and concentration for elements lower than 1500 μg g‐1 with logarithmic correlation coefficients between ‐0.75 and ‐0.86. There is also a clear trend of increasing RSD with decreasing concentration from NIST SRM 610 through SRM 612 to SRM 614. These suggest that the difference in the scatter of apparent element concentrations is not due to chemical heterogeneity but reflects analytical uncertainty. It is concluded that all these glasses are, overall, homogeneous on a scale of 60 μm. Our first results on BHVO‐2G and BIR‐1G showed that they generally agreed with BHVO‐2/BHVO‐1 and BIR‐1 within 10% relative. Exceptions were Nb, Ta and Pb in BHVO‐2G, which were 14‐45% lower than reference values for BHVO‐2 and BHVO‐1. Be, Ni, Zn, Y, Zr, Nb, Sn, Sb, Gd, Tb, Er, Pb and U in BIR‐1G were also exceptions. However, of these elements, Be, Nb, Sn, Sb, Gd, Tb, Pb and U gave results that were consistent within an uncertainty of 2s between our data and BIR‐1 reference values. Results on NIST SRM 612 agreed well with published data, except for Mg and Sn. This was also true for elements with m/z 85 (Rb) in the case of NIST SRM 614. The good agreement between measured and reference values for Na and Mg in BCR‐2G, BHVO‐2G and BIR‐1G, and for Al and Na in NIST SRM 610, 612 and 614 up to concentrations of at least several weight percent (which were possible to analyse due to the dynamic range of 108) indicates the suitability of this technique for major, minor and trace element determinations. 相似文献
104.
Tina van de Flierdt Martin Frank James R Hein Detlef Günther 《Earth and Planetary Science Letters》2004,222(1):259-273
Secular variations in the Pb isotopic composition of a mixed hydrogenous-hydrothermal ferromanganese crust from the Bauer Basin in the eastern Equatorial Pacific provide clear evidence for changes in hydrothermal contributions during the past 7 Myr. The nearby Galapagos Rise spreading center provided a strong hydrothermal flux prior to 6.5 Ma. After 6.5 Ma, the Pb became stepwise more radiogenic and more similar to Equatorial Pacific seawater, reflecting the westward shift of spreading to the presently active East Pacific Rise (EPR). A second, previously unrecognized enhanced hydrothermal period occurred between 4.4 and 2.9 Ma, which reflects either off-axis hydrothermal activity in the Bauer Basin or a late-stage pulse of hydrothermal Pb from the then active, but waning Galapagos Rise spreading center.Hafnium isotope time-series of the same mixed hydrogenous-hydrothermal crust show invariant values over the past 7 Myr. Hafnium isotope ratios, as well as Nd isotope ratios obtained for this crust, are identical to that of hydrogenous Equatorial Pacific deep water crusts and clearly indicate that hydrothermal Hf, similar to Nd, does not travel far from submarine vents. Therefore, we suggest that hydrothermal Hf fluxes do not contribute significantly to the global marine Hf budget. 相似文献
105.
106.
Kay-Christian Emeis David M. Anderson Heidi Doose Dick Kroon Detlef Schulz-Bull 《Quaternary Research》1995,43(3)
Arabian Sea sediments record changes in the upwelling system off Arabia, which is driven by the monsoon circulation system over the NW Indian Ocean. In accordance with climate models, and differing from other large upwelling areas of the tropical ocean, a 500,000-yr record of productivity at ODP Site 723 shows consistently stronger upwelling during interglaciations than during glaciations. Sea-surface temperatures (SSTs) reconstructed from the alkenone unsaturation index (UK′37) are high (up to 27°C) during interglaciations and low (22-24°C) during glaciations, indicating a glacial-interglacial temperature change of >3°C in spite of the dampening effect of enhanced or weakened upwelling. The increased productivity is attributed to stronger monsoon winds during interglacial times relative to glacial times, whereas the difference in SSTs must be unrelated to upwelling and to the summer monsoon intensity. The winter (NE) monsoon was more effective in cooling the Arabian Sea during glaciations then it is now. 相似文献
107.
Shashi B. Verma Dennis D. Baldocchi Dean E. Anderson Detlef R. Matt Robert J. Clement 《Boundary-Layer Meteorology》1986,36(1-2):71-91
Fluxes of CO2, latent heat and sensible heat were measured above a fully-leafed deciduous forest in eastern Tennessee with the eddy correlation technique. These are among the first reported observations over such a surface. The influences of solar radiation, vapor pressure deficit and the aerodynamic and canopy resistances on these mass and energy exchanges are examined. Following a concept introduced by McNaughton and Jarvis (1983), examination of our data suggest that the water vapor exchange of a deciduous forest is not as strongly coupled with net radiation as is that of agricultural crops. The degree of decoupling is smaller than in the case of a coniferous forest. This difference may be attributable in part to the greater aerodynamic resistance to water vapor transfer in a deciduous forest. It appears that the concept of decoupling may be extended to the CO2 exchange of a deciduous forest as well.Published as Paper No. 7832, Journal Series, Nebraska Agricultural Research Division. ATDD Contribution No. 85-17. 相似文献
108.
109.
Stabilizing greenhouse gas concentrations at low levels: an assessment of reduction strategies and costs 总被引:2,自引:8,他引:2
Detlef P. van Vuuren Michel G. J. den Elzen Paul L. Lucas Bas Eickhout Bart J. Strengers Bas van Ruijven Steven Wonink Roy van Houdt 《Climatic change》2007,81(2):119-159
On the basis of the IPCC B2, A1b and B1 baseline scenarios, mitigation scenarios were developed that stabilize greenhouse
gas concentrations at 650, 550 and 450 and – subject to specific assumptions – 400 ppm CO2-eq. The analysis takes into account a large number of reduction options, such as reductions of non-CO2 gases, carbon plantations and measures in the energy system. The study shows stabilization as low as 450 ppm CO2-eq. to be technically feasible, even given relatively high baseline scenarios. To achieve these lower concentration levels,
global emissions need to peak within the first two decades. The net present value of abatement costs for the B2 baseline scenario
(a medium scenario) increases from 0.2% of cumulative GDP to 1.1% as the shift is made from 650 to 450 ppm. On the other hand,
the probability of meeting a two-degree target increases from 0%–10% to 20%–70%. The mitigation scenarios lead to lower emissions
of regional air pollutants but also to increased land use. The uncertainty in the cost estimates is at least in the order
of 50%, with the most important uncertainties including land-use emissions, the potential for bio-energy and the contribution
of energy efficiency. Furthermore, creating the right socio-economic and political conditions for mitigation is more important
than any of the technical constraints. 相似文献
110.
Manuela Krügel Daniela Thaller Volker Tesmer Markus Rothacher Detlef Angermann Ralf Schmid 《Journal of Geodesy》2007,81(6-8):515-527
The combination of tropospheric parameters derived from different space-geodetic techniques has not been of large interest
in geodesy so far. However, due to the high correlation between station coordinates and tropospheric parameters, the latter
should not be neglected in combinations. This paper deals with the comparison and combination of tropospheric parameters derived
from global positioning system (GPS) and very long baseline interferometry (VLBI) observations stemming from a 15-day campaign
of continuous VLBI observations in 2002 (CONT02). The observation data of both techniques were processed homogeneously to
avoid systematic differences between the solutions. We compared the tropospheric estimates of GPS and VLBI at eight co-location
sites and found a very good agreement in the temporal behavior of the tropospheric zenith path delays (ZPD), reflected by
correlation factors up to 0.98. Following this, a combination of the tropospheric parameters was performed. We demonstrate
that the combination of tropospheric parameters leads to a stabilization of combined station networks. This becomes visible
in the improvement of the repeatabilities of the station height components. Furthermore, the potential use of independent
data from water vapor radiometers (WVRs) to validate space-technique-derived tropospheric parameters was investigated. Correlation
coefficients of 0.95 or better were estimated between the tropospheric parameters of WVR and GPS or VLBI. Additionally, the
utility of the tropospheric parameters for validation of local tie vectors was investigated. Both tropospheric zenith delays
and tropospheric gradients were found to be very suitable to validate the height component and the horizontal components of
the local tie, respectively. 相似文献