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M. Rex P. Von Der Gathen G.O. Braathen N.R.P. Harris E. Reimer A. Beck R. Alfier R. Krüger-carstensen M. Chipperfield H. De Backer D. Balis F. O'Connor H. Dier V. Dorokhov H. Fast A. Gamma M. Gil E. Kyrö Z. Litynska I.S. Mikkelsen M. Molyneux G. Murphy S.J. Reid M. Rummukainen C. Zerefos 《Journal of Atmospheric Chemistry》1999,32(1):35-59
The chemically induced ozone loss inside the Arctic vortex during the winter 1994/95 has been quantified by coordinated launches of over 1000 ozonesondes from 35 stations within the Match 94/95 campaign. Trajectory calculations, which allow diabatic heating or cooling, were used to trigger the balloon launches so that the ozone concentrations in a large number of air parcels are each measured twice a few days apart. The difference in ozone concentration is calculated for each pair and is interpreted as a change caused by chemistry. The data analysis has been carried out for January to March between 370 K and 600 K potential temperature. Ozone loss along these trajectories occurred exclusively during sunlit periods, and the periods of ozone loss coincided with, but slightly lagged, periods where stratospheric temperatures were low enough for polar stratospheric clouds to exist. Two clearly separated periods of ozone loss show up. Ozone loss rates first peaked in late January with a maximum value of 53 ppbv per day (1.6 % per day) at 475 K and faster losses higher up. Then, in mid-March ozone loss rates at 475 K reached 34 ppbv per day (1.3 % per day), faster losses were observed lower down and no ozone loss was found above 480 K during that period. The ozone loss in hypothetical air parcels with average diabetic descent rates has been integrated to give an accumulated loss through the winter. The most severe depletion of 2.0 ppmv (60 %) took place in air that was at 515 K on 1 January and at 450 K on 20 March. Vertical integration over the levels from 370 K to 600 K gives a column loss rate, which reached a maximum value of 2.7 Dobson Units per day in mid-March. The accumulated column loss between 1 January and 31 March was found to be 127 DU (36 %). 相似文献
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FENG Weiheng FENG Yun Shanghai Gamma Ray Technology Co. Ltd. Laohumin Rd. Shanghai 《《地质学报》英文版》2000,74(3):685-691
The main reason why the application of nuclear technology in petroleum exploration has not yet been accepted by most exploration workers is that they are not clear about the homologous distribution features of oil and gas fields and radioactive radiation. The authors hold that the disequilibrium of uranium, radium and radon as a natural radioactive series is the basic feature in the use of this technology in petroleum exploration. The invention Gamma-ray Spectral Measurement of the Equilibium Coefficient Kp and Its Embodiment of the senior author now can readily solve that problem and replace the impedient measure of normalization of uranium and potassium to thorium that had to be proposed before. Application of this impedient measure has some limitations. In areas where the surface is covered by beach or river sands, thorium minerals such as monazite may be concentrated by placering. This could result in local thorium highs that would yield local uranium and potassium lows after normalization to thoriu 相似文献
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Indonesia has turned its alleged role as global leader of land-based carbon emissions into a role as a global trailblazer exploring modalities for Reducing Emissions from Deforestation and Forest Degradation (REDD+). REDD+ readiness is largely about improving forest governance, but this itself is a multilayered concept. This article analyses how the processes and practices of REDD+ readiness are leading to various forest governance reforms in Indonesia. We analysed six dimensions of REDD+ readiness progress over the past six years and the way these interact with land tenure reform and land-use planning. We found evidence that (1) tenure issues are taken more seriously, as evidenced by the development of social safeguard mechanisms and efforts to accelerate the gazettement of forest boundaries, although a constitutional court recognition in 2013 for customary forest management is, however, yet to be operationalized; (2) spatial planning relates forests more clearly to other parts of the landscape in terms of compliance with Nationally Appropriate Mitigation Actions (NAMAs) commitments; and (3) the forest and peatland conversion moratorium initiative led to a revamping of forest management. Despite progress, there are still major obstacles to full REDD+ implementation in Indonesia. The discussion focuses on the weaker part of readiness and possible ways forward. 相似文献
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