Optical Properties of Aged Free Tropospheric Aerosol Over the Northern Atlantic: Analysis of 2012-2014 Data

Wednesday, 17 December 2014
Kendra Wright1, Lynn R Mazzoleni2, Paulo JLCS Fialho3, Katja Dzepina1, Detlev Helmig4, Jacques Hueber4, Michael Dziobak2, Sumit Kumar5, Swarup China1, Noopur Sharma6 and Claudio Mazzoleni1, (1)Michigan Technological University, Houghton, MI, United States, (2)Michigan Technological Univers, Houghton, MI, United States, (3)University of the Azores, Azores, Portugal, (4)University of Colorado at Boulder, Institute of Arctic and Alpine Research, Boulder, CO, United States, (5)National Center for Medium Range Weather Forecasting, Noida, India, (6)Michigan Technological Univ, Houghton, MI, United States
The Azores are a volcanic archipelago located 1500km west of Lisbon, Portugal in the North Atlantic Ocean. A 2351 meter dormant volcano lies on the 447 km2island of Pico with a population of around 15,000. Its location and orography are such that the summit typically lies above the well mixed marine boundary layer. A station was established in the caldera of the volcano at 2225 m by the late Dr. Richard Honrath in collaboration with the University of the Azores and began collecting data in 2001. A seven-wavelength aethalometer was employed to measure the black carbon equivalent mass concentration in the free troposphere since then. In 2012 a three wavelength nephelometer was added to measure total light scattering and back scattering due to aerosol. In 2013 an optical particle counter was added. Aerosol, including black carbon, play an important role in atmospheric processes for a number of reasons including different radiative forcing effects, acting as a cloud condensation and ice nuclei and changing surface albedo of snow.

We present the wavelength-dependent aerosol optical properties measured during the 2012, 2013 and 2014 sampling seasons along with particle count data when available. Several events with high aerosol concentrations are investigated in detail.