...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Geophysical Research. Biogeosciences >Global atmospheric distributions and source strengths of light hydrocarbons and tetrachloroethene [Review]
【24h】

Global atmospheric distributions and source strengths of light hydrocarbons and tetrachloroethene [Review]

机译：轻烃和四氯乙烯的全球大气分布和源强[综述]

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The atmospheric distributions of CH4. C2H6, C3H8, C2H2, and C2Cl4 and their annual chemical removal rates in steady state are determined Versus latitude using a modified version of the Oslo two-dimensional global tropospheric photochemical model. A photochemically calculated hydroxyl radical distribution, which has been validated with methylchloroform data, and seasonally varying surface measurements of the title species are used to compute their respective global annual surface source strengths and steady state lifetimes. Computed annual surface source strengths of CH4, C2H6, C3H8, C2H2, and C2Cl4 are 490, 10.4, 8.4, 3.1 Tg (1 Tg = 10(12) g), and 432 kT (1 kT = 10(9) g), respectively. The calculated annual chemical removal rates of these compounds show distinct latitudinal distributions. Because their steady state global lifetimes are less than the model interhemispheric exchange time (about 1 year), the calculated north to south ratios of the deduced surface emission strengths of C2H6, C3H8, C2H2, and C2Cl4 probably reflect the locations of their sources. Within the limits of previously estimated industrial emissions of C2Cl4 (3-4 kT) for the southern hemisphere, our calculations indicate that about 47 kT of additional southern hemispheric source of C2Cl4 is required for 1989-1990 to attain steady state mass balance in this region. There are two possibilities for this needed source: either other industrial sources are missing, or there are unidentified natural sources of C2Cl4. So far, oceans have been suggested as a natural source. Normalization of monthly varying ratios of hemispherically averaged calculated surface mixing ratios of C2H6, C3H8, and C2H2 and their respective observed mixing ratios with respect to those for C2Cl4 indicates that the sources of these hydrocarbons are seasonal in nature. It is also shown that convective transport effectively redistributes these short-lived species but their calculated surface source strengths are relatively independent of this transport process. [References: 115]
机译：CH4的大气分布。使用Oslo二维全球对流层光化学模型的修改版，通过纬度确定C2H6，C3H8，C2H2和C2Cl4及其在稳态下的年度化学去除率。用甲基氯仿数据验证了光化学计算的羟基自由基分布，并使用了季节性变化的标题物种表面测量值来计算其各自的全球年度表面源强度和稳态寿命。 CH4，C2H6，C3H8，C2H2和C2Cl4的年表面源强度的计算值分别为490、10.4、8.4、3.1 Tg（1 Tg = 10（12）g）和432 kT（1 kT = 10（9）g），分别。计算出的这些化合物的年度化学去除率显示出不同的纬度分布。由于它们的稳态全球寿命小于模型的半球交换时间（约1年），因此推算出的C2H6，C3H8，C2H2和C2Cl4的表面发射强度的南北比值可能反映了其来源位置。在先前估计的南半球C2Cl4工业排放量（3-4 kT）的范围内，我们的计算表明，在1989-1990年期间，为了达到该区域的稳态质量平衡，还需要大约47 kT的南半球C2Cl4来源。 。此所需来源有两种可能：要么缺少其他工业来源，要么存在未确定的C2Cl4天然来源。迄今为止，已经有人建议将海洋作为自然资源。对C2H6，C3H8和C2H2的半球平均计算表面混合比的月变化比以及它们相对于C2Cl4的各自观察到的混合比进行归一化表明，这些烃的来源本质上是季节性的。还显示，对流输运有效地重新分配了这些短命物种，但其计算的表面源强度却相对独立于该输运过程。 [参考：115]

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号