Mixing ratios of tropospheric carbon monoxide measured by a gas filter radiometer carried aboard the space shuttle during November 1981 are reported. The data represent average mixing ratios in the middle and upper troposphere between 38°N and 38°S latitude. Approximately 10,000 individual measurements were obtained in each of the two channels of the instrument. The data are presented in the form of plots that show the individual carbon monoxide mixing ratio measurements as a function of latitude and longitude and in the form of maps that show the data averaged over 5° latitude by 5° longitude squares. The data show relatively little variation in the mixing ratio in the southern hemisphere; however, the data from both the tropics and the northern hemisphere show strong gradients with both latitude and longitude.

The Measurement of Air Pollution from Satellite (MAPS) experiment measured the distribution of middle tropospheric carbon monoxide (CO) from the space shuttle during October 1984. The data represent average mixing ratios in the middle troposphere between 57°N and 57°S. Approximately 75,000 individual CO measurements were obtained during the 9‐day mission. The data are presented in maps that show the CO mixing ratios averaged over 5° latitude by 5° longitude areas for 6 days of the mission. Comparisons with concurrent, direct measurements taken aboard aircraft show that the inferred concentrations are systematically low by 20–40% depending upon which direct measurement calibration standard is used. The data show that there are very large CO sources resulting from biomass burning over South America and southern Africa. Measured mixing ratios were high over northeast Asia and were highly variable over Europe.

During the second flight of the space shuttle, the measurement of air pollution from satellites (MAPS) experiment in the OSTA-1 payload acquired approximately 35 hours of radiometric measurements of the carbon monoxide mixing ratio in the middle troposphere, upper troposphere, and lower stratosphere. A gas filter radiometer operating in the 4.67-micrometer band was used to acquire the data over the region from 38 degrees N to 38 degrees S during both daytime and nighttime. The performance of the measurement system was excellent. The data reduced to date indicate the presence of significant gradients in the middle tropospheric carbon monoxide mixing ratio with both latitude and longitude over the North Atlantic, the Mediterranean Sea, and the Middle East. On the basis of comparisons with directly measured values, the accuracy of the measurements is approximately 15 percent. Comparisons of data taken on successive orbits over the same geographic region indicate that the repeatability of the measurements is approximately 5 percent.

No abstract

The MAPS (Measurement of Air Pollution from Satellites) experiment, which flew as part of the OSTA-1 payload on the second flight of the Space Shuttle (STS-2) during early November 1981, was the first attempt to measure a known air pollutant in the troposphere from an orbiting platform. The experiment was designed to remotely measure the mixing ratio of carbon monoxide in the middle and upper troposphere using a gas filter radiometer as the sensing instrument.