title: Global-scale seasonally resolved black carbon vertical profiles over the Pacific.
abstract: [1] Black carbon (BC) aerosol loadings were measured during the High-performance Instrumented Airborne Platform for Environmental Research Pole-to-Pole Observations (HIPPO) campaign above the remote Pacific from 85°N to 67°S. Over 700 vertical profiles extending from near the surface to max ∼14 km altitude were obtained with a single-particle soot photometer between early 2009 and mid-2011. The data provides a climatology of BC in the remote regions that reveals gradients of BC concentration reflecting global-scale transport and removal of pollution. BC is identified as a sensitive tracer of extratropical mixing into the lower tropical tropopause layer and trends toward surprisingly uniform loadings in the lower stratosphere of ∼1 ng/kg. The climatology is compared to predictions from the AeroCom global model intercomparison initiative. The AeroCom model suite overestimates loads in the upper troposphere/lower stratosphere (∼10×) more severely than at lower altitudes (∼3×), with bias roughly independent of season or geographic location; these results indicate that it overestimates BC lifetime.
authors: Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration Boulder, Colorado, USA ; Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Colorado, USA.
authors: J P
authors: JP
authors: Schwarz
authors: Center for International Climate and Environmental Research - Oslo (CICERO) Oslo, Norway.
authors: B H
authors: BH
authors: Samset
authors: Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration Boulder, Colorado, USA ; Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Colorado, USA.
authors: A E
authors: AE
authors: Perring
authors: Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration Boulder, Colorado, USA ; Science and Technology Corporation Boulder, Colorado, USA.
authors: J R
authors: JR
authors: Spackman
authors: Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration Boulder, Colorado, USA.
authors: R S
authors: RS
authors: Gao
authors: Atmospheric, Oceanic and Planetary Physics, Department of Physics, University of Oxford Oxford, UK.
authors: P
authors: P
authors: Stier
authors: Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette, France.
authors: M
authors: M
authors: Schulz
authors: Global Monitoring Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration Boulder, Colorado, USA.
authors: F L
authors: FL
authors: Moore
authors: Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration Boulder, Colorado, USA ; Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Colorado, USA.
authors: Eric A
authors: EA
authors: Ray
authors: Chemical Sciences Division, Earth System Research Laboratory, National Oceanic and Atmospheric Administration Boulder, Colorado, USA ; Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Colorado, USA.
authors: D W
authors: DW
authors: Fahey
keywords: AeroCom; HIPPO; aerosol; black carbon; remote; tropical tropopause layer