Intercomparison of general purpose clear sky atmospheric radiative transfer models for the millimeter/submillimeter spectral range
Intercomparison of general purpose clear sky atmospheric radiative transfer models for the millimeter/submillimeter spectral range
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DOI：
10.1029/2004rs003110
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发表时间：
2005-02
期刊：
影响因子：
1.6
通讯作者：
C. Melsheimer;C. Verdes;Stefan Buehler;Claudia Emde;P. Eriksson;D. Feist;S. Ichizawa;Viju O. John;Y. Kasai;G. Kopp;N. Koulev;T. Kuhn;Oliver Lemke;Satoshi Ochiai;F. Schreier;T. R. Sreerekha;Makoto Suzuki;C. Takahashi;S. Tsujimaru;J. Urban
中科院分区：
文献类型：
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作者：
C. Melsheimer;C. Verdes;Stefan Buehler;Claudia Emde;P. Eriksson;D. Feist;S. Ichizawa;Viju O. John;Y. Kasai;G. Kopp;N. Koulev;T. Kuhn;Oliver Lemke;Satoshi Ochiai;F. Schreier;T. R. Sreerekha;Makoto Suzuki;C. Takahashi;S. Tsujimaru;J. Urban
我们比较了一些辐射传输模型的大气探测在毫米和亚毫米波长范围内，检查它们的一致性，并调查他们的偏差彼此。这种相互比较涉及辐射传输模型的三个不同方面：（1）气体吸收线的固有物理特性及其建模方法，（2）吸收系数的计算，以及（3）不同几何形状的辐射传输的完整计算，即，向上看向下看和四肢看通过将计算结果与预定义的光谱数据、谱线形状、连续吸收模型和频率网格进行比较，测试了实现的正确性和一致性。由不同模型计算的吸收系数和亮度温度一般在1%以内。此外，模型结果的可变性或不确定性估计，如果（除了大气情景）的输入，如光谱数据，线的形状，和连续吸收模型可以自由选择。在这里，模型在主要吸收线的中心周围彼此偏离约10%。这种差异的主要原因是报告的光谱数据线吸收和连续吸收模型的可变性。差异的其他可能原因是不同的频率和压力网格以及相应插值例程的差异，以及所使用的线形函数的差异，即货车-Vleck-Weisskopf线形函数的（ν/ν0）或（ν/ν0）2的前因子。差异是否影响检索结果仍有待于对每个应用程序单独进行调查。
We compare a number of radiative transfer models for atmospheric sounding in the millimeter and submillimeter wavelength range, check their consistency, and investigate their deviations from each other. This intercomparison deals with three different aspects of radiative transfer models: (1) the inherent physics of gaseous absorption lines and how they are modeled, (2) the calculation of absorption coefficients, and (3) the full calculation of radiative transfer for different geometries, i.e., up‐looking, down‐looking, and limb‐looking. The correctness and consistency of the implementations are tested by comparing calculations with predefined input such as spectroscopic data, line shape, continuum absorption model, and frequency grid. The absorption coefficients and brightness temperatures calculated by the different models are generally within about 1% of each other. Furthermore, the variability or uncertainty of the model results is estimated if (except for the atmospheric scenario) the input such as spectroscopic data, line shape, and continuum absorption model could be chosen freely. Here the models deviate from each other by about 10% around the center of major absorption lines. The main cause of such discrepancies is the variability of reported spectroscopic data for line absorption and of the continuum absorption model. Further possible causes of discrepancies are different frequency and pressure grids and differences in the corresponding interpolation routines, as well as differences in the line shape functions used, namely a prefactor of (ν/ν0) or (ν/ν0)2 of the Van‐Vleck‐Weisskopf line shape function. Whether or not the discrepancies affect retrieval results remains to be investigated for each application individually.