Measurements of Pollution in the Troposphere (MOPITT) aboard the Terra satellite. Since 1999, it has contributed to the study of environmental pollution by continuously scanning the troposphere to make long-term measurements of carbon monoxide concentrations. Initially planned for a five-year term, this experiment has been prolonged because the data collected is still of high quality and the satellite is in good health. Its data are used to assess the scope of certain pollution control initiatives and to help understand environmental effects of other human activities such as biomass burning.