Goals
The scientific goals for the ACE mission include:
- Understanding the chemical and dynamical processes that control the distribution of ozone in the stratosphere and upper troposphere, particularly in the Arctic
- Exploring the relationship between atmospheric chemistry and climate change
- Studying the effects of biomass burning on the free troposphere
- Measuring aerosols and clouds to reduce the uncertainties in their effects on the global energy balance
Results Overview
The Atmospheric Chemistry Experiment (ACE) was launched on SCISAT in August 2003. After initial spacecraft and instrument commissioning and characterization, good science data was obtained in February 2004. Since that time, SCISAT has completed over 118,000 orbits and the ACE instruments have measured more than 145,000 occultations.
With over 20 years of measurements, ACE has had a major scientific impact. In addition to continuing to accomplish its primary goal of helping to understand the chemical and dynamical processes that control the distribution of ozone in the stratosphere and upper troposphere, particularly in the Arctic, it makes extensive contributions in other areas such as the monitoring of greenhouse gases and air pollution. Ozone chemistry is particularly important because changes – at present primarily of anthropogenic origin – in atmospheric ozone, lead to increased damaging ultraviolet (UV) radiation reaching the ground and also affects climate. As of September 1, 2025, the science output, as indicated by the number of papers published, currently totals 732. The rate of publication has generally increased with time, so the prospect for the future is excellent. In addition, its longevity has enhanced the value of its data and, due to the demise of other missions, it is now the sole provider of some data types to the global community. ACE is widely admired internationally as a model for a successful small-satellite science mission.