Autonomous ozone, aerosol, and water vapor profiling of the atmosphere

Tropospheric ozone, aerosols, and water vapor are important atmospheric constituents that affect air quality and climate. For instance, ozone is a short-lived climate pollutant that is photochemically active with nitrogen oxides, and its concentration in the troposphere can be significantly increased by stratospheric– tropospheric exchange events. In addition, aerosols contribute to the radiative budget, are a tracer for pollution transport, and they affect visibility, cloud formation, and air quality. Lastly, water vapor plays a pivotal role in climate change and atmospheric stability because it influences many atmospheric processes (e.g., cloud formation and photochemical atmospheric reactions). It is therefore important to measure the abundance of these atmospheric components in a synergistic way, to support the development of air-quality forecasts and diagnostic models. Such measurements can also be used for validating satellite observations that provide a regional to global perspective. Lidar (light detection and ranging) technology has rapidly advanced over the past several decades. From a number of different platforms, this technique can now be used to measure a variety of atmospheric constituents with ever increasing accuracy and at ever finer scales. Although the number of lidar instruments continues to increase worldwide, these platforms generally require an operator (particularly high-powered lidar systems).1, 2 To overcome the need for a lidar operator, our team at Environment and Climate Change Canada (ECCC) have previously designed several autonomous aerosol lidar systems3 to support a number of research objectives. For example, we have recently developed an autonomous mobile lidar system (see Figure 1) Figure 1. Photograph of the Autonomous Mobile Ozone Lidar Instrument for Tropospheric Experiments (AMOLITE) mounted in a climatecontrolled mobile trailer.