描述大洋洲地表空气中7Be浓度的年度循环行为。

Describing the annual cyclic behaviour of 7Be concentrations in surface air in Oceania.

作者信息

Doering Che, Akber Riaz

机构信息

Radiological Laboratory, School of Physical and Chemical Sciences, Queensland University of Technology, 2 George Street, Brisbane, Qld. 4000, Australia.

出版信息

J Environ Radioact. 2008 Oct;99(10):1703-7. doi: 10.1016/j.jenvrad.2008.02.002. Epub 2008 Mar 28.

DOI:10.1016/j.jenvrad.2008.02.002

PMID:18375023

Abstract

Surface air concentrations of 7Be at a number of stations in Oceania show a distinct annual cycle. We apply a sinusoidal model to describe this cycle. The results show that peak 7Be concentrations in surface air occur during early spring at tropical latitudes and during mid-to-late summer at middle latitudes. Comparison with available 90Sr surface air data for the southern hemisphere indicates that stratosphere-to-troposphere exchange is an active atmospheric process controlling the 7Be annual cycle throughout the Oceania region. Vertical transport of air within the troposphere also seems to influence the observed annual cycle. Seasonality in rainfall is not thought to control the annual cyclic behaviour of 7Be in surface air.

摘要

大洋洲多个站点的地表空气中(^{7})Be的浓度呈现出明显的年度周期。我们应用正弦模型来描述这个周期。结果表明，热带地区地表空气中(^{7})Be浓度峰值出现在早春，中纬度地区则出现在夏中至夏末。与南半球现有的(^{90})Sr地表空气数据对比表明，平流层到对流层的交换是控制整个大洋洲地区(^{7})Be年度周期的一个活跃大气过程。对流层内空气的垂直输送似乎也会影响观测到的年度周期。降雨的季节性被认为不是控制地表空气中(^{7})Be年度循环行为的因素。