GML Seminars

Particles in the atmosphere are important for different reasons in different parts of the world. In areas where there are a lot of humans, they are important because of their adverse effect on human health and reduction in visibility. In the remote troposphere, they have a large impact on the brightness and longevity of clouds. In the stratosphere, they can cause ozone destruction and potentially change large scale circulation. And in all locations, they interact with solar radiation, often scattering some light back into space, temporarily masking the warming effect of CO2.

In this talk I will present the results from two airborne field campaigns connecting microphysical and optical measurements of particles. The first field campaign, FIREX-AQ, was focused on wildfires emissions. Smoke from wildfires is important because of the expectation of increasing wildfires, but also due to its historical contribution to a pre-industrial climate. I will present in situ measurements of the aerosol optical properties that show that fresh wildfires smoke scatters approximately 20% more light into space than conventional models would predict. This is important for both radiative forcing estimates and for remote sensing techniques that use the light scattered into space to infer wildfire smoke emissions.

The second airborne field campaign, AEROMMA, was focused on urban emissions, but was also heavily influenced by a severe wildfire season. This work is in progress and being led by Dr. Han Huynh. The goal is to create a comprehensive and validated model of aerosol composition and optical properties in and around large American and Canadian cities. The purpose of this model is a) to evaluate common assumptions about how aerosols are represented in models and b) provide a comprehensive dataset for validating remote sensing retrieval algorithms. The data that was collected and used in this model coincides with the newly operational TEMPO satellite, but we hope that by converting in situ measurements into parameters and formats that are accessible to the community, we can provide value to a wide range of modelers and remote sensing algorithm developers.