Tropospheric Aerosol Radiative Forcing Observational Experiment (TARFOX), 1996

TARFOX was an IGAC activity that operated from 10-31 July 1996 and was established to provide information about the direct effects of tropospheric aerosols on the eastern seaboard of the United States. The principal goals were to:

• Measure the direct effects of tropospheric aerosols on regional radiation budgets of the cloud-free atmosphere, while simultaneously measuring the chemical, physical, and optical properties of the responsible aerosols

• Perform a radiative “column closure” study, using the degree of consistency and analyses of aerosol properties and effects to assess and reduce uncertainties in predicted aerosol climate effects

• Guide planning for future aerosol studies, such as ACE-2

• Extend measurements and analyses to other periods and regions with similar aerosol properties, using validated satellite remote sensing methods

The activity included a combined ground, air, and space data collection to gather a wide variety of closure analyses. The early results from the activity indicated an unexpected importance of carbonaceous compounds and water condensed on aerosols in the East Coast haze plume. TARFOX was used to gather information on the composition and physical properties of aerosols in vertical columns in the lower troposphere. Data concluded that about 50% of the total aerosol mass was contributed by carbonaceous materials (sulfate was the only significant inorganic constituent of the aerosol). Also, it was found that the carbonaceous mass fraction was a function of the altitude, increasing at higher altitudes due to its resilience from being removed from the atmosphere. TARFOX demonstrated that carbonaceous materials in the atmosphere need to be given more examination. The results and data sets have been used to apply to the analyses of the absorption of solar radiation by black carbon (BC). Various articles have been published as a result of the data collected during the TARFOX activity, including publications in Journal of the Atmospheric Sciences and the Journal of Geophysical Research. More information about TARFOX and publications can be found here.