TRACER-BC2-SP2

The focus of this project is to assess black carbon and brown carbon aerosol in Houston during the TRACER campaign through the co-located deployment of a single-particle soot photometer (SP2) with the University of Houston/Baylor University aerosol optical instrumentation in the Texas (BC)2 network in and around Houston. The deployment of the SP2 will enable us to expand the spatial assessment of black carbon (BC) in Houston during TRACER by enabling a more thorough characterization of BC, including sources, transport, and potential processing. BC is well known to undergo physical and chemical changes during local and long-range transport that will impact its optical properties. By deploying multiple SP2s in the Houston area, the impacts of local and long-range transport can be assessed. The TRACER-BC2-SP2 will expand spatial and temporal characterization of BC in the Houston area during TRACER and link the TRACER black carbon analysis to ongoing black and brown carbon monitoring (Texas (BC)2 network) in Houston. Further, the deployment of the SP2 will enable spatial and seasonal characterization of black carbon to be conducted during TRACER.

To realize this objective, the major scientific goals of this project will be:

A. To understand urban processing of fresh black carbon emissions:

1. Conduct measurements of refractory BC at multiple sites in Houston to assess spatial variability.
2. Calculate the BC mass absorption cross-sections (MACs) at multiple sites in Houston to assess both the temporal and spatial variability in and around the Houston area.

B. To elucidate the processing of black carbon from biomass burning during both local and long-range transport:

1. Identification and intercomparison with tropospheric aerosol particles (TAPs) for wavelength dependence of absorption.
2. Size distribution of BC:
   1. Changes in size distribution in local versus long-range plumes.
   2. Assessment of BB-BC mixing state in the boundary layer.
3. Calculation of MAC during different BB plumes.

Timeline