...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental Science & Technology >Statistical Approach for Assessing the Stockholm Convention's Effectiveness: Great Lakes Atmospheric Data
【24h】

Statistical Approach for Assessing the Stockholm Convention's Effectiveness: Great Lakes Atmospheric Data

机译：评估《斯德哥尔摩公约》有效性的统计方法：大湖区大气数据

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 implementation of the Stockholm Convention (SC) in 2004 should become evident in decreases in environmental concentrations of various pollutants even in countries that not have ratified the SC. However, in some cases, there may be no decreases at all. This paper develops a statistical strategy for investigating time-series measurements such that the rate of change of a pollutant's concentrations at any time can be compared to those at an earlier or later time and thus determine the effectiveness of the SC at any location. The general approach is to modify a first-order regression to include a second order time term: ln(C-t)= a(0) + a(1) t + a(2) t(2), where C, is the concentration at time t. Thus, the rate constant at any time is k(t) = a(1) + 2 a(2) t. Given that the errors associated with a(1) and a(2) can be calculated, one can compare the rate constants at different times with statistical rigor to determine if the rates at which the concentrations are changing are significantly different. As examples of this approach, this paper uses vapor and particle phase atmospheric concentrations of several organic pollutants measured at six sites around the North American Great Lakes every 12 days since about 1992. After correcting for the population near the sampling sites, for seasonality, and for the different numbers of samples collected on the same date, up to 830 data were used in this second-order regression. In general, the loss rates of vapor phase chlorinated pesticides have slowed by about a factor of 2 between 1995 and 2015, which is not SC-like behavior. The exceptions are the endosulfans, the vapor and particle phase concentrations of which were both doubling in 1995 but were both decreasing in 2015, probably because of the greatly diminished use of this insecticide in the United States over the last 20-25 years. The loss rates of vapor phase polychlorinated biphenyls became more rapid between 1995 and 2015, which is SC-like behavior.
机译：即使在尚未批准该公约的国家中，各种污染物的环境浓度降低也应在2004年实施《斯德哥尔摩公约》。但是，在某些情况下，可能根本没有减少。本文开发了一种用于研究时间序列测量的统计策略，以便可以将污染物在任何时间的浓度变化率与之前或之后的时间进行比较，从而确定SC在任何位置的有效性。通用方法是修改一阶回归以包括二阶时间项：ln（Ct）= a（0）+ a（1）t + a（2）t（2），其中C是浓度在时间t。因此，任何时候的速率常数为k（t）= a（1）+ 2 a（2）t。假定可以计算与a（1）和a（2）相关的误差，则可以将不同时间的速率常数与统计严格度进行比较，以确定浓度变化的速率是否显着不同。作为这种方法的示例，本文使用了自1992年以来每12天在北美大湖周围六个地点测量的几种有机污染物的汽相和粒子相大气浓度。校正采样地点附近的人口，季节性和对于同一日期收集的不同数量的样本，此二次回归中最多使用了830个数据。通常，气相氯化农药的损失率在1995年至2015年之间降低了约2倍，这不是类似SC的行为。硫丹是个例外，硫丹的气相和颗粒相浓度在1995年都翻了一番，但在2015年都在下降，这可能是由于过去20-25年美国这种杀虫剂的使用大大减少了。气相多氯联苯的损失率在1995年至2015年之间变得更快，这是类似SC的行为。

著录项

  • 来源
    《Environmental Science & Technology》 |2019年第15期|8585-8590|共6页
  • 作者

    Hites Ronald A.;

  • 作者单位

    Indiana Univ, ONeill Sch Publ & Environm Affairs, Bloomington, IN 47405 USA;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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