Webinars

Webinar series 2024 | The science of particulate measurements

This year's edition was created to share information about our latest developments for particulate monitoring, including AirPhoton instruments capabilities with GRASP processing, a new approach for urban scale pollution modeling and an introduction to GRASP open-source algorithm. You can access the recordings of session 1 and 2 in this page. These videos are a ressource for scientists, researchers, and anyone interested in particulate monitoring for their operational applications.

Session 1: Determining PM2.5 mass with Nephelometer optical measurements

Tue 3rd Sept, 2024; Wed 4th Sept, 2024 | Dr. Chong Li

Typically nephelometers use optical measurements to provide information about bulk particulate properties such as size and amount. AirPhoton nephelometers offer features that allow us to use GRASP to pull out additional information from the raw measurements such as size distribution and particulate mass. The SPARTAN network deploys our nephelometers around the globe alongside our filter based particle sampling stations. This provides us a unique data set to compare real time optical measurements and PM 2.5 retrievals with gravimetric based PM 2.5 measurements in a variety of environments and conditions. In our first webinar Dr. Chong Li will present the results of the work she has been doing with GRASP and machine learning to obtain PM2.5 dry mass estimates from AirPhoton nephelometer measurements deployed by the SPARTAN network.

Session 2: Modeling Street Level PM Dispersal

Tue 8th Oct, 2024; Wed 9th Oct, 2024 | Dr. Konstantin Kuznetsov

The use of satellite data for urban pollution monitoring has been studied for over 25 years. The most serious limitations are the lack of spatially high-resolution data and the inability to obtain vertical resolution to understand exposure at ground level. A new generation of higher resolution satellite data for air quality monitoring as well as several techniques for improving ground level exposure estimates are under development. We are applying a new approach which combines satellite data with Computational Fluid Dynamics (CFD) modeling to retrieve road emissions and pollution concentrations at a detailed 1-meter resolution. This method developed by Dr Konstantin Kuznetsov simulates pollution dispersion in urban environments, accounting for factors like buildings, roads, and vegetation.

Session 3: Introduction to GRASP open-source algorithm

Tue 5th Nov, 2024 | Dr. Oleg Dubovik | recording not available.

The final session of the webinar series introduced the GRASP open-source algorithm. Developed over 30 years, GRASP – Generalized Retrieval of Atmosphere and Surface Properties – is a highly accurate aerosol retrieval algorithm that processes properties of aerosol and land surface reflectance, inferfeering in nearly 50 aerosol and surface parameters and workinf under different conditions, including bright surfaces such as deserts, where the reflectance overwhelms the signal of aerosols. GRASP is highly versatile and allows input from a wide variety of satellite and surface measurements. Currently used by major space agencies worldwide, GRASP algorithm is the operational product for recognized missions like Sentinel-4, 3MI and CO2M, being widely discussed in the scientific literature with over 80,000 citations and with an open-source community of over 1,500 users.

Workshop and training program 2025

We are currently preparing the 2025 agenda for our upcoming workshops, trainings and webinars. Stay informed about all the latest updates and opportunities.