近日，西班牙国家研究委员会物理化学研究所Alfonso Saiz-Lopez团队研究了火星热带地区近地表臭氧层增强的证据。2025年11月17日出版的《美国科学院院刊》杂志发表了这项成果。

臭氧在行星大气化学、近地表化学过程及紫外辐射吸收中均扮演关键角色。

研究组报道了利用美国"火星2020"任务搭载的火星环境动态分析器（MEDA）辐射与尘埃传感器（RDS）中的臭氧探测仪，在火星地表获得的臭氧观测结果，这些数据与既往地基及轨道观测相互印证。测量数据采集于杰泽罗撞击坑当地正午时分，在远日点期间获得的平均臭氧柱浓度为3.8±2.3微米-大气柱（1σ），该数值已低于北半球夏季的不确定性范围。

此次获取的柱浓度数据与先前通过轨道器和地基望远镜的观测结果吻合良好。综合"火星2020"及其他任务在远日点期间的总臭氧柱浓度测量，结合轨道器获得的垂直剖面观测，表明约90%的臭氧集中在20公里以下大气层，而远日点期间的高空臭氧层对总柱浓度贡献微弱。这一高度以下的臭氧浓度水平达到模型预测值的3至4倍，对当前火星低层大气化学与成分的认知形成挑战。可能的解释包括：气溶胶减少了臭氧的分解路径，和/或火星近地表大气中存在未知的活性化学过程。这两种情形都将显著改变当前模型对火星低层大气氧化能力的预测。

附：英文原文

Title: Evidence of an enhanced near-surface ozone layer at tropical latitudes on Mars

Author: Viúdez-Moreiras, Daniel, Smith, Michael D., Wolff, Mike, Brown, Megan A. J., Daerden, Frank, Zorzano, María-Paz, Apestigue, Víctor, Arruego, Ignacio, García, Elisa, Jiménez, Juan J., Toledo, Daniel, Lemmon, Mark T., Knutsen, Elise Wright, Saiz-Lopez, Alfonso

Issue&Volume: 2025-11-17

Abstract: Ozone plays a key role in both atmospheric and near-surface chemistry, as well as in UV absorption in planetary atmospheres. Here, we report observations of ozone from the surface of another planet, using the ozone detector included in the Mars Environmental Dynamics Analyzer (MEDA) Radiation and Dust Sensor (RDS) aboard NASA’s Mars 2020 mission, complementing previous space-based and ground-based observations from Earth. Measurements were acquired at Jezero Crater, Mars, at midday, retrieving an average ozone column abundance of 3.8 ± 2.3 μm-atm (1σ) around aphelion, which fell below uncertainties in northern summer. The retrieved column abundance is in reasonable agreement with previous space-based and ground-based observations from Earth. The measurements of total ozone column abundance around aphelion from Mars 2020 and other missions, together with vertical profile observations from orbit, indicate that ~90% of the observed ozone is confined below 20 km of altitude, the aphelion layer weakly contributing to the total column abundance. These ozone levels below 20 km are 3 to 4 times higher than those predicted by models, challenging current understanding of atmospheric chemistry and composition in the lower atmosphere of Mars. It may be possible that aerosols are reducing the destruction pathways of ozone and/or that unknown active chemistry in the near-surface atmosphere of Mars is at work. Both cases should strongly modify the oxidizing capacity in the lower atmosphere of Mars from current model predictions.

DOI: 10.1073/pnas.2511744122

Source: https://www.pnas.org/doi/abs/10.1073/pnas.2511744122