B J Huebert, S Howell, L Zhuang, M Litchy, D Wylie, and J.
(All at: Department of Oceanography, University of Hawaii, Honolulu, HI 96822; 808-956-6896; email: email@example.com)
We measured nonseasalt sulfate (NSS) and methanesulfonate (MSA) in particles < 1 um in diameter from the NCAR C-130 during the ACE-1 experiment. On two occasions we followed the evolution of airmasses for more than 24 hours by tagging the air with smart balloons and using their GPS-derived locations to make multiple flights into the same air. Since the air was moving toward colder water, the boundary layer tended to be stable, with only a small surface mixed layer. This complicates the process of constructing chemical budgets.
In both Lagrangian experiments, we noted that the concentrations of MSA and NSS increased during the daytime and remained relatively constant at night. This is consistent with their production by photochemical mechanisms. We will discuss formation mechanisms and infer rates from the observed concentration changes.