Petrology     

Ralph Kretz 《Earth》1991,30(3-4):328-329

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Deposition of trace substances via cloud interception on a coniferous forest at Kleiner Feldberg     

S. Pahl  P. Winkler  T. Schneider  B. Arends  D. Schell  R. Maser  W. Wobrock 《Journal of Atmospheric Chemistry》1994,19(1-2):231-252

A resistance model to calculate the deposition of cloud droplets on a coniferous forest and some improved parameterizations of the indispensable input parameters are described. The deposition model is adapted to the coniferous forest at the Kleiner Feldberg site and verified by the data of a drip water monitoring station below the forest canopy. The measurements of liqud water content, wind speed and trace substance compounds in cloud water of the Ground-based Cloud Experiment (GCE) at Kleiner Feldberg in 1990 are used to calculate the cloud water deposition fluxes and the deposition of trace substances via cloud water interception. The calculated deposition of trace substances via cloud water interceptions is three to six times higher than via rain during the experiment. On a long term data basis the yearly amount of cloud water deposition is 180 mm year^–1 at Kleiner Feldberg site (840 m a.s.l.) while the precipitation amount is 1030 mm year^–1. Due to higher trace substance concentrations in cloud water compared to rain the ionic deposition via cloud water interception and via precipitation were assessed to be of comparable magnitude.  相似文献   

Editorial     

Stephen H. Schneider 《Climatic change》1985,7(4):365-366

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Loss of metals from pelites during regional metamorphism   总被引：3，自引：0，他引：3  

U. Haack  H. Heinrichs  M. Boneß  A. Schneider 《Contributions to Mineralogy and Petrology》1984,85(2):116-132

In aluminous metapelites the ratio H₂O⁺/K₂O decreases with increasing metamorphic grade and degree of reaction. This ratio is a very practical indicator for the progress of the mineral reconstitution during progressive metamorphism. With decreasing values of the ratio H₂O⁺/ K₂O the Cu concentration and the following element ratios also decrease either continuously or in stepwise fashion: Tl/K₂O, Ba/K₂O, Pb/K₂O, Bi/K₂O, Hg/K₂O, Sr/Na₂O, Zn/(Fe²⁺+Mg), Cd/(Fe²⁺+Mg); Rb/K₂O remains approximately constant. In the aluminous metapelites of the Damara Orogen in Namibia the following losses occur between the biotite isograd and anatexis: 61% Cu, 20% Tl, 34% Ba, 59% Pb, 86% Bi, 46% Hg, 30% Sr, 25% Zn, 31% Cd. Thus the potential of regional metamorphism to form hydrothermal deposits in the low grade environment should not be neglected.  相似文献   

Deforestation and climatic modification — an editorial     

Stephen A. Schneider 《Climatic change》1984,6(3):227-229

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‘Natural experiments’ and CO2-induced Climate Change: The controversy drags on — An editorial     

Stephen H. Schneider 《Climatic change》1984,6(4):317-321

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Editorial     

D. D. Klemm  Hans -J. Schneider 《Mineralium Deposita》1984,19(1):1-1

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Forecasting in the social and natural sciences: An overview and analysis of isomorphisms   总被引：1，自引：0，他引：1  

Kenneth C. Land  Stephen H. Schneider 《Climatic change》1987,11(1-2):7-31

This article identifies and analyzes several points of similarity in the structure and context of forecasting in the social and natural sciences. These include: the limits of identities or universal laws as a basis for forecasts; the corresponding need for simplifying parametric representations of one or more of the variables that enter into identities; various sources of uncertainty about parameterizations; intrinsic limitations on predictability or forecasting accuracy in large-scale systems; the need for sensitivity analyses of model responses to changes in exogenous variables and/or parametric structures; problems of model linkage; and the social (organizational and political) context of forecasts. Suggestions for future lines of inquiry are made in each case. Several of these are such that they can benefit from a sharing of experience and expertise across disciplinary lines.The research reported herein was supported in part by the IC² Institute, The University of Texas at Austin, and in part by National Science Foundation Grant Number SES-8411702. However, the opinions expressed in the paper are those of the authors and do not necessarily reflect those of the sponsoring organizations. We appreciate the advice and comments of Jesse H. Ausubel, Robert S. Chen, Judith Jacobsen, and Richard C. Rockwell on earlier versions of this paper.The National Center for Atmospheric Research is sponsored by the National Science Foundation.  相似文献   

Estimates of CO2 from wood fuel based on forest harvest data     

Ralph M. Rotty 《Climatic change》1986,9(3):311-325

Wood continues to be a major fuel source for vast numbers of the world's people. Even in the highly industrialized countries, use of wood and wood wastes as fuel produces a small (in comparison to fossil fuels) but non-negligible amount of CO₂. Although information on the worldwide harvest and use of wood is not as complete or as reliable as fossil fuel data, this paper uses what is available and develops annual estimates of CO₂ emissions for the period 1968–1983. Woods are separated into two types, coniferous and non-coniferous, and average content and carbon amounts are estimated for each type. Wood utilization is divided into several categories, e.g., fuelwood, lumber, poles, and use of wood wastes as fuels in the lumber and paper industries is included. Results are given for major world regions. In recent years the worldwide CO₂ emissions from wood used as fuels is estimated to be about one-tenth as much as CO₂ emissions from fossil fuels. This does not include fires in the forests, either associated with forest clearing or those from natural causes.  相似文献   

Editorial: Three essays of remembrance on the life of Helmut Landsberg     

Stephen H. Schneider 《Climatic change》1986,9(3):259-259

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