An aircraft experiment is described that measured atmospheric carbon monoxide (CO) to characterize the distribution and transport of this fire product in a special air mass circulation region of central Brazil. Biomass burning directly injects CO into the lower troposphere, near the surface, and mixing and transport processes then distribute it to the whole troposphere. Satellite images of fire pixels were used to characterize the distribution of fires in the study area. Air mass trajectories were calculated in order to exactly determine the origin of the polluted air masses. Calculations are then made of the proportion of CO concentrations that are observed at a certain point and which are the result of the transportation of this pollutant from source regions. In the northern part of the state of Mato Grosso, as well as the southern part of the state of Goias, for example, up to 200 ppbv of CO (about 70% of the observed concentration) are the result of imports from stronger source regions. In the north of the state of Paraná, the imported amount of CO is about 45% of the observed value.
Carbon monoxide; Biomass burning; Pollutants; Fire pixels
