Atmospheric Chemistry Experiment

SCISAT, also known as the Atmospheric Chemistry Experiment (ACE), is a Canadian Space Agency small satellite mission for remote sensing of the Earth's atmosphere using solar occultation. The satellite was launched on 12 August 2003 and continues to function perfectly. The primary mission goal is to improve our understanding of the chemical and dynamical processes that control the distribution of ozone in the stratosphere and upper troposphere, particularly in the Arctic. The high precision and accuracy of solar occultation makes SCISAT useful for monitoring changes in atmospheric composition and the validation of other satellite instruments. The satellite carries two instruments. A high resolution (0.02 cm-¹) infrared Fourier transform spectrometer (FTS) operating from 2 to 13 microns (750-4400 cm-¹) is measuring the vertical distribution of trace gases, particles and temperature. This provides vertical profiles of atmospheric constituents including essentially all of the major species associated with ozone chemistry. Aerosols and clouds are monitored using the extinction of solar radiation at 1.02 and 0.525 microns as measured by two filtered imagers. The vertical resolution of the FTS is about 3-4 km from the cloud tops up to about 150 km. Peter Bernath of the University of Waterloo is the principal investigator. A dual optical spectrograph called MAESTRO (Measurement of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation) covers the 400-1030 nm spectral region and measures primarily ozone, nitrogen dioxide and aerosol/cloud extinction. It has a vertical resolution of about 1-2 km. Tom McElroy of Environment and Climate Change Canada is the principal investigator. ACE data are freely available from the University of Waterloo website. SCISAT was designated an ESA Third Party Mission in 2005. ACE data are freely available through an ESA portal.

SCISAT，亦称大气化学实验（ACE），系加拿大航天局一项针对地球大气遥感探测的小型卫星任务，采用太阳掩星技术进行。该卫星于2003年8月12日发射升空，至今运行状态良好。其主要目标在于深化我们对控制平流层和上层对流层中臭氧分布的化学和动力学过程的理解，尤其是在北极地区。由于太阳掩星技术的精度与精确度极高，SCISAT在监测大气成分变化以及验证其他卫星仪器方面具有重要价值。卫星搭载了两种仪器。一种高分辨率（0.02 cm⁻¹）的2至13微米（750-4400 cm⁻¹）红外傅里叶变换光谱仪（FTS），测量微量气体、颗粒物和温度的垂直分布，提供包括与臭氧化学相关的主要物种在内的所有大气成分的垂直分布轮廓。通过两个滤波成像仪测量的1.02和0.525微米的太阳辐射消光，监测气溶胶和云层。FTS的垂直分辨率约为云顶上方3-4公里至约150公里。滑铁卢大学的彼得·伯纳思（Peter Bernath）担任首席研究员。另一种名为MAESTRO（通过掩星测量平流层和对流层气溶胶消光）的双光栅光谱仪，覆盖400-1030 nm光谱范围，主要测量臭氧、二氧化氮以及气溶胶/云层的消光。其垂直分辨率约为1-2公里。加拿大环境与气候变化部的汤姆·麦克劳利（Tom McElroy）担任首席研究员。ACE数据可通过滑铁卢大学网站免费获取。SCISAT于2005年被指定为欧洲航天局（ESA）的第三方任务。ACE数据可通过ESA门户免费获取。