Bernard J. Firanski

Preliminary Analysis of Night‐time Aerosol Optical Depth Retrievals at a Rural, Near‐urban Site in Southern Canada

In the summer of 2007, a SPSTAR03 starphotometer was installed at Egbert, Canada (44°13′ N, 79°45′ W, alt 264 m) and a continuous series of initial measurements was performed between August 26 and September 19. Several sunphotometry parameters such as the aerosol optical depth (AOD) and the “fine” and “coarse” optical depths were extracted from the SPSTAR03 extinction spectra. The SPSTAR03 data was analyzed in conjunction with sunphotometry and zenith‐pointing lidar data acquired during the same time period. Preliminary results show coarse continuity between the day‐ and night time AOD values (with the mean difference between the measured and the interpolated values being 0.05) as well as a qualitative correlation between the “fine” and “coarse” optical depths and the normalized lidar backscatter coefficient profiles. It was also found that the spectra produced with the differential two‐star measurement method were sensitive to non‐horizontally homogeneous differences in the line‐of‐sight conditions of bo...

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.

A fully autonomous ozone, aerosol and night time water vapor LIDAR: a synergistic approach to profiling the atmosphere in the Canadian oil sands region

P. 3, line 8: I am not sure if these two references are suitable for documenting ozone production in biomass-burning plumes. This process has been verified at lower latitudes, but there is doubt in ozone formation at high latitudes. See also my remarks below. The reference of Aggarwal et al. was chosen because it is another recent documented case of ozone production in a biomass-burning plume in the region. Also added another reference

Preliminary tropospheric ozone DIAL, water vapour, and aerosol lidar measurements during ARC-IONS

A new lidar instrument, dubbed AeRO (Aerosol Raman Ozone) Lidar, is being developed at Environment Canadas Centre For Atmospheric Research Experiments (CARE). The new system will use three lasers to simultaneously measure ozone, water vapour and aerosol profiles (including extinction) from near ground to the tropopause. The main thrust will focus on understanding Air Quality within the airshed with the capability of looking at Stratospheric Tropospheric Exchange (STE) processes to determine the magnitude and frequency of such events leading to elevated levels of tropospheric ozone. In addition a wind profiler through a partnership with University of Western Ontario will soon be deployed to CARE to provide complementary observations of the tropopause. The lidar participated in the ARC-IONS field campaign during April and July of 2008. During the field campaign, daily ozonesondes were released to further compliment the lidar measurements. Details of the system design and preliminary results from the lidar measurements will be presented.