Premuda Margherita, Palazzi Elisa, Ravegnani Fabrizio, Bortoli Daniele, Masieri Samuele, Giovanelli Giorgio
Institute of Atmospheric Sciences and Climate, National Research Council (ISAC-CNR), via Gobetti 101, 40129 Bologna, Italy.
Opt Express. 2012 Mar 26;20(7):7973-93. doi: 10.1364/OE.20.007973.
This paper describes the radiative transfer model (RTM) MOCRA (MOnte Carlo Radiance Analysis), developed in the frame of DOAS (Differential Optical Absorption Spectroscopy) to correctly interpret remote sensing measurements of trace gas amounts in the atmosphere through the calculation of the Air Mass Factor. Besides the DOAS-related quantities, the MOCRA code yields: 1- the atmospheric transmittance in the vertical and sun directions, 2- the direct and global irradiance, 3- the single- and multiple- scattered radiance for a detector with assigned position, line of sight and field of view. Sample calculations of the main radiometric quantities calculated with MOCRA are presented and compared with the output of another RTM (MODTRAN4). A further comparison is presented between the NO2 slant column densities (SCDs) measured with DOAS at Evora (Portugal) and the ones simulated with MOCRA. Both comparisons (MOCRA-MODTRAN4 and MOCRA-observations) gave more than satisfactory results, and overall make MOCRA a versatile tool for atmospheric radiative transfer simulations and interpretation of remote sensing measurements.
本文介绍了在差分光学吸收光谱法（DOAS）框架下开发的辐射传输模型（RTM）MOCRA（蒙特卡罗辐射分析），该模型通过计算空气质量因子来正确解释大气中痕量气体含量的遥感测量结果。除了与DOAS相关的量之外，MOCRA代码还能得出：1-垂直和太阳方向的大气透过率，2-直接辐照度和总辐照度，3-对于具有指定位置、视线和视场的探测器的单次和多次散射辐射率。给出了用MOCRA计算的主要辐射量的示例计算结果，并与另一个RTM（MODTRAN4）的输出结果进行了比较。还给出了在埃武拉（葡萄牙）用DOAS测量的二氧化氮斜柱密度（SCD）与用MOCRA模拟的结果之间的进一步比较。这两个比较（MOCRA-MODTRAN4和MOCRA-观测结果）都给出了非常令人满意的结果，总体而言，使MOCRA成为大气辐射传输模拟和遥感测量解释的通用工具。
