Strong localized pumping of water vapor to high altitudes on Mars during the perihelion season

1. Description of methods used for collection/generation of data:The Nadir and Occultation for MArs Discovery (NOMAD) instrument is an spectrometer covering the spectral range between 0.2 to 4.3 µm. Its solar occultation (SO) channel acquires transmittance spectra at different diffraction orders sounding the limb of the Martian atmosphere. It uses a 4 lines/mm echelle grating in a litrow configuration. An Acousto-Optical Tunable Filter (AOTF) is used to select different diffraction orders. The spectral resolution of the SO channel is λ/∆λ=20,000. After spectral calibration, the vertical profiles are obtained using the state-of-the-art line-by-line Karlsruhe Optimized Radiative transfer Algorithm (KOPRA). The IAA level-2 processor relies on multi-parameter non-linear least squares fitting of measured and modeled spectra. The profiles in this data set have been obtained analyzing the NOMAD SO diffraction orders 134 (3011-3035 cm-1), 136 (3056-3081 cm-1), 168 (3775-3805 cm-1) and 169 (3798-3828 cm-1). 2. This dataset also includes simulations obtained from KOPRA, ASIMUT and PSG forward models. The spectral range of the simulations cover the spectral range from 3370 to 3430 cm-1, with a mean spectral resolution of 5e-4, 2e-3 and 3e-4 cm-1 respectively.1. 数据采集/生成方法说明：火星探索天底与掩星（Nadir and Occultation for MArs Discovery, NOMAD）仪器是一台覆盖0.2~4.3 µm光谱范围的光谱仪。其太阳掩星（solar occultation, SO）通道可获取不同衍射级次的透射光谱，用于探测火星大气临边。该通道采用利特罗（Littrow）构型的4线/mm阶梯光栅，并借助声光可调谐滤波器（Acousto-Optical Tunable Filter, AOTF）选取不同衍射级次。其太阳掩星通道的光谱分辨率为λ/∆λ=20000。完成光谱定标后，采用当前主流的逐线计算 Karlsruhe 优化辐射传输算法（Karlsruhe Optimized Radiative transfer Algorithm, KOPRA）获取大气垂直廓线。IAA二级处理器依托实测与模拟光谱的多参数非线性最小二乘拟合完成反演。本数据集的廓线通过分析NOMAD的SO通道衍射级次134（3011~3035 cm⁻¹）、136（3056~3081 cm⁻¹）、168（3775~3805 cm⁻¹）以及169（3798~3828 cm⁻¹）得到。 2. 本数据集还包含源自KOPRA、ASIMUT和PSG正向模型的模拟数据。模拟数据的光谱范围覆盖3370~3430 cm⁻¹，三者的平均光谱分辨率分别为5×10⁻⁴ cm⁻¹、2×10⁻³ cm⁻¹和3×10⁻⁴ cm⁻¹。