On the Determination of Age of Air Trends from Atmospheric Trace Species
On the Determination of Age of Air Trends from Atmospheric Trace Species
复制标题
从大气痕量物种测定空气趋势年龄
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
D. Kinnison
中科院分区：
文献类型：
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作者：
R. Garcia;W. Randel;D. Kinnison
摘要在数值模式中，痕量化学物种被用来计算空气年龄（AOA），AOA是平均纬向环流强度的量度。AOA的趋势也被计算出来，并发现在温室气体随时间增加的模拟中是负的，这与在这些条件下计算的平均纬向环流的加速是一致的。这一模拟结果最近已经使用SF6和CO2的观测结果进行了检验，SF6是一种寿命很长的物种，其大气浓度在过去半个世纪迅速增加，CO2也是寿命很长的物种，并随着时间的推移而增加。令人惊讶的是，从这些气体估算的AOA在1975-2005年期间没有显示出明显的趋势。在这里，全大气群落气候模式（WACCM）被用来从SF6和CO2在1965-2006年期间的AOA的估计。计算出的AOA产生的趋势小于从合成的线性增长的轨迹得到的趋势。
Abstract Trace chemical species have been used in numerical models to calculate the age of air (AOA), which is a measure of the strength of the mean meridional circulation. The trend in the AOA has also been computed and found to be negative in simulations where greenhouse gases increase with time, which is consistent with the acceleration of the mean meridional circulation calculated under these conditions. This modeling result has been tested recently using observations of SF6, a very long lived species whose atmospheric concentration has increased rapidly over the last half century, and of CO2, which is also very long lived and increasing with time. Surprisingly, the AOA estimated from these gases exhibits no significant trend over the period 1975–2005. Here the Whole Atmosphere Community Climate Model (WACCM) is used to derive estimates of the AOA from SF6 and CO2 over the period 1965–2006. The calculated AOA yields trends that are smaller than the trend derived from a synthetic, linearly growing trac...