Enhance your knowledge with our pre-conference courses on Monday, October 4, 2021.

Aerosol Data from the Next Generation of Satellites for Air Quality & Climate Research
Monday, October 4, 2021 • 8:00 am - 5:00 pm
Instructors: Dr. Pawan Gupta, Senior Scientist, USRA/NASA Marshall Flight Center; Dr. Robert Levy, Research Physical Scientist, NASA Goddard Space Flight Center

The Moderate Resolution Imaging Spectroradiometer (MODIS) sensors aboard NASA’s Earth Observing Satellites (EOS) have been observing the earth-atmosphere system for nearly two decades. Atmospheric aerosols (particulate matter) play an important role in earth radiation budget and contribute to air pollution. Since its launch, the “dark-target” (DT) aerosol retrieval algorithm has been applied to MODIS to retrieve aerosol optical depth (AOD) and other aerosol properties on a global scale. The AOD data product has been extensively used for both climate and air quality applications. More recently, the DT algorithm is being applied to the next generation of sensors such as Visible Infrared Imaging Radiometer Suite (VIIRS) on Suomi-NPP, and the Advanced Himawari and Baseline Imagers (AHI and ABI) on Himawari-8 and GOES-R. The application of consistent algorithm on multiple Low Earth Orbiting (LEO) and GEO stationary (GEO) sensors is key for observing aerosols with high temporal and spatial resolution. 

This course will provide lectures and hands-on exercises. Lectures will be about fundamentals of satellite remote sensing of atmospheric aerosols, the dark target aerosol retrieval method, and best research practices. Hands-on exercises will be geared towards accessing data, reading and mapping the aerosol fields, and validating against ground measurements. All activities will use free or open-source software tools.
Contemporary Aerosol Optics
Monday, October 4, 2021 • 8:00 am - 12:00 pm
Instructors: Dr. Rajan Chakrabarty, Assistant Professor of Energy, Environmental and Chemical Engineering, Washington University in St. Louis; Rebecca Washenfelder, Research Chemist, Tropospheric Chemistry, NOAA, Boulder CO; Hans Moosmuller, Professor of Physics, Desert Research Institute, Reno NV

This course will outline the importance of aerosol optics for estimating visibility impairment and radiative forcing of climate, identifying the relevant optical parameters that are needed for understanding and modeling. This will be followed by a general discussion of aerosol physics before focusing on contemporary measurement and characterization techniques of aerosol optical properties. Computational electromagnetic techniques discussed will include both exact calculation methods and useful approximations while the discussion on experimental techniques will include state-of-the-art in situ, filter-based, and remote sensing techniques and instruments for quantification of aerosol scattering, absorption, and extinction coefficients, phase functions and asymmetry parameters.
Back Trajectory Analysis
Monday, October 4, 2021 • 8:00 am - 12:00 pm
Instructor: Kristi Gebhart, Research Physical Scientist, Cooperative Institute for Research in the Atmosphere

Back trajectories are often used for insight into source-receptor relationships and have a long history of use in visibility studies.  Bring your laptop to get some hands-on practice automating tasks such as downloading gridded input meteorological data, running the Hysplit back trajectory model in batch mode, and plotting and analyzing the output. The course will include a booklet with practical instructions, tips and tricks learned the hard way, equations and code for some common back trajectory analyses, and where to find resources for additional support. It is helpful, but not necessary, if participants already have Python and R installed on their laptops and have some familiarity with these packages.  All software can run on Windows, Linux, or Apple computers.
Low Cost Sensors
Monday, October 4, 2021 • 8:00 am - 12:00 pm
Instructor: Dr. Jay Turner, Vice Dean for Education and Professor of Energy, Environmental and Chemical Engineering, Washington University in St. Louis

Air pollution monitoring devices based on low-cost sensors (LCS) are now widely used to interrogate previously unmonitored environments and to increase monitoring density in areas where high spatiotemporal variability is anticipated. This course will highlight the opportunities and challenges when deploying such devices. The governing physical principles behind LCS will be used to clarify appropriate applications. Use cases will be presented to demonstrate strengths and limitations. Efforts to define performance targets and testing protocols will be summarized, and key considerations for the effective deployment of LCS will be discussed.      
The Relationship of Visibility to Particle Composition and Sources
Monday, October 4, 2021 • 1:00 pm - 5:00 pm
Instructors: Dr. Philip K. Hopke, Bayard D. Clarkson Distinguished Professor Emeritus at Clarkson University and Adjunct Professor, Department of Public Health Sciences of the University of Rochester School of Medicine and Dentistry

This course will present the underlying basis for differences in the interaction of light with particles of differing composition and the relationships that have been developed for prediction of visible range based on particle composition. Visibility can also be related to sources. The conceptual framework of receptor models, a mass balance approach, will be described. The resulting mathematical approaches can be then implemented depending on what a priori information is available. Applications of several types of models to various particle composition problems will be described with an emphasis on the practical use of Positive Matrix Factorization for both elemental and organic species data.
The Role of Aerosols in the Earth’s Radiative Balance
Monday, October 4, 2021 • 1:00 pm - 5:00 pm  (This course will be taught remotely.) 
Instructor: Dr. Nicolas Bellouin, Associate Professor of Climate Processes, Department of Meteorology, University of Reading, United Kingdom

Life on earth is made possible by an energetic cycle where solar radiation is converted by the earth system into heat, which is mainly stored in the oceans, and terrestrial radiation, which is emitted back to space. At equilibrium and on an annual average, incoming radiative fluxes balance their outgoing counterparts and the heat content in the system remains constant. Atmospheric aerosols play multiple roles both in the maintenance and perturbation of the earth’s radiative balance.

This course will review those roles, covering the radiative aspects of the interactions between aerosols and radiation, aerosols and clouds, and aerosols and other elements of the earth’s system, including surface properties and atmospheric composition. For each interaction, the course will identify the relevant aerosol physical and chemical properties. Finally, the course will look at how aerosols emitted from human activities have upset the radiative balance of the earth by exerting a radiative forcing over the industrial era. This course will provide lectures based on the latest research and class exercises.