FY 1998

Carbon monoxide measurements from 76°N to 59°S and over the South Tasman Sea

Kok, G.L., A.S.H. Prévôt, R.D. Schillawski, and J.E. Johnson

J. Geophys. Res., 103(D13), 16,731–16,736, doi: 10.1029/98JD00527 (1998)

In November and December of 1995, carbon monoxide (CO) measurements were made in a Pacific transect and over the South Tasman Sea as part of the First Aerosol Characterization Experiment (ACE 1) program. Airborne CO measurements were made from 76°N to 59°S. A clear latitudinal gradient in CO concentrations was measured, with the southern hemisphere average about 80 parts per billion by volume (ppbv), and increasing to 120-130 ppbv at the most northern latitudes. Plumes of CO with a 30-40 ppbv concentration increase over the general background concentrations could be seen at several latitudes. The National Oceanic and Atmospheric Administration R/V Discoverer made CO measurements over the South Tasman Sea from November 15 to December 9, 1995. A systematic decrease of 0.31 ppbv/d CO was observed. Vertical profile measurements of CO from near the ocean surface to 2500 m altitude during the Lagrangian B intensive of ACE 1 suggested the mixing of stratospheric air with reduced CO concentrations.