Sensitivity of stratospheric inorganic chlorine to differences in transport
Sensitivity of stratospheric inorganic chlorine to differences in transport
复制标题
平流层无机氯对传输差异的敏感性
DOI：
10.5194/acp-7-4935-2007
复制
发表时间：
2007
影响因子：
6.3
通讯作者：
P. Newman
中科院分区：
文献类型：
--
作者：
D. Waugh;S. Strahan;P. Newman
正确模拟平流层无机氯（Cl y）是模拟平流层臭氧过去和未来演变的关键。然而，最近的平流层臭氧消耗国际评估中使用的化学气候模型的比较表明，模拟的Cl y存在很大差异，这些差异解释了下一个世纪臭氧模拟演变中的许多差异。在这里，我们研究运输的作用，在确定模拟氯y使用三个模拟相同的离线化学传输模型，具有相同的对流层低边界条件和相同的化学求解器，但不同的分辨率和/或气象领域。这些模拟表明，运输起着关键作用，在确定氯y分布，和氯y取决于时间尺度和运输途径。空气在平流层中停留的时间（例如，平均年龄）是决定平流层Cl y的重要输送因子，但平均年龄与Cl y的关系并不简单。平流层下层Cl y取决于平流层上层的空气比例，具有相同平均年龄的模型之间的传输差异可能导致有机氯转化为Cl y的比例差异。运输途径的差异导致不同的氟氯化碳的垂直剖面，观测和模拟的氟氯化碳剖面的比较提供了一个严格的测试模型中的运输途径。
Correctly modeling stratospheric inorganic chlorine (Cl y ) is crucial for modeling the past and future evolution of stratospheric ozone. However, comparisons of the chemistry climate models used in the latest international assessment of stratospheric ozone depletion have shown large differences in the modeled Cl y , with these differences explaining many of the differences in the simulated evolution of ozone over the next century. Here in, we examine the role of transport in determining the simulated Cl y using three simulations from the same off-line chemical transport model that have the same lower tropospheric boundary conditions and the same chemical solver, but differing resolution and/or meteorological fields. These simulations show that transport plays a key role in determining the Cl y distribution, and that Cl y depends on both the time scales and pathways of transport. The time air spends in the stratosphere (e.g., the mean age) is an important transport factor determining stratospheric Cl y , but the relationship between mean age and Cl y is not simple. Lower stratospheric Cl y depends on the fraction of air that has been in the upper stratosphere, and transport differences between models having the same mean age can result in differences in the fraction of organic chlorine converted into Cl y . Differences in transport pathways result in differences in vertical profiles of CFCs, and comparisons of observed and modeled CFC profiles provide a stringent test of transport pathways in models.