CO2 baseline concept in 3-D atmospheric transport models
CO2 baseline concept in 3-D atmospheric transport models
复制标题
3-D 大气传输模型中的 CO2 基线概念
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
P. Monfray
中科院分区：
文献类型：
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作者：
M. Ramonet;P. Monfray
大气传输模型现在通常用于估计CO2的源和汇的分布，给出对这种温室气体的大气测量。然而，为了正确评估大尺度通量模式，必须只采用那些代表大尺度空气质量的测量。通常，根据不同的标准过滤观察到的时间序列，作为选择基线条件的平均值。在本文中，我们提出的问题比较选定的数据与整个模拟时间序列。为了更好地与观测的一致性，我们提出了四个程序来选择传输模型中的基线期。每一个测试与高分辨率的3-D模型（TM 2 z），在3个监测站目前使用的建模社区（角格里姆，角米尔斯，和阿姆斯特丹岛）。结果表明，这种选择是必要的，特别是对沿海台站。通过使用由5天后向轨迹或氡-222浓度估计的天气输送信息，CO2天气尺度变率（全年平均）减少了三分之一。季节性周期（峰-峰振幅）也减少了约30%的两个沿海站。通过这些修正，模型-数据一致性显著提高。此外，年平均值可能受到ppmv的十分之几的影响。最后，我们还调查了在观测和模拟中被归类为非基线的天气事件。三维模型再现这些数据的某些特征的能力，指出了这些数据在描述区域通量强度方面的潜力。DOI：10.1034/j.1600-0889.1996.t01-2-00008.x
Atmospheric transport models are now commonly used to estimate the distribution of sources and sinks of CO 2 , given atmospheric measurements of this greenhouse gas. Yet, to properly assess large-scale flux patterns, one must employ only those measurements that are representative of large scale air masses. Typically the observed time series are filtered, according to different criteria, as a mean to select baseline conditions. In this paper we raise the problem of comparing selected data with the whole simulated time series. Aiming for better consistency with the observations, we propose four procedures to select the baseline periods in the transport models. Each is tested with a high resolution 3-D model (TM2 z ), at 3 monitoring stations currently used by the modeling community (Cape Grim, Cape Meares, and Amsterdam Island). Results demonstrate that such selection is necessary, especially for coastal stations. By using information on the synoptic transport as estimated by either 5-days backtrajectories or radon-222 concentrations, the CO 2 synoptic scale variability (averaged over the year) is reduced by a factor of three. The seasonal cycle (peak-to-peak amplitude) is also reduced by about 30% for the two coastal stations. With these corrections, the model-data agreement improves dramatically. Moreover, annual averages can be affected by few tenths of ppmv. Finally, we also investigate synoptic events classified as non-baseline both in observations and simulations. The ability of the 3-D model to reproduce some characteristics of these data, points out the potential of such data to characterize the strength of regional fluxes. DOI: 10.1034/j.1600-0889.1996.t01-2-00008.x