CARBON-MONOXIDE MEASUREMENTS FROMM 76-DEGREES-N TO 59-DEGREES-S AND OVER THE SOUTH TASMAN-SEA

In November and December of 1995, carbon monoxide (CO) measurements we re made in a Pacific transect and over the South Tasman Sea as part of the First Aerosol Characterization Experiment (ACE 1) program. Airbor ne CO measurements were made from 76 degrees N to 59 degrees S. A clea r latitudinal gradient in CO concentrations was measured, with the sou thern 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 backgr ound concentrations could be seen at several latitudes. The National O ceanic and Atmospheric Administration R/V Discoverer made CO measureme nts over the South Tasman Sea from November 15 to December 9 1995. A s ystematic decrease of 0.31 ppbv/d CO was observed. Vertical profile me asurements of CO from near the ocean surface to 2500 m altitude during the Lagrangian B intensive of ACE 1 suggested the mixing of stratosph eric air with reduced CO concentrations.