Understanding the composition of Earth’s atmosphere is important for both air quality and climate change. The atmosphere is changing. Some of the gases that now enter the atmosphere from both human activity and natural processes are hazardous to our health. Rising greenhouse gas concentrations are causing Earth’s climate to warm.
Satellites allow NASA to identify sources of air pollution and track how chemicals move through the atmosphere. They help measure how much greenhouse gases are causing Earth to warm, and how warming is changing the atmosphere.
Terra and Atmospheric Composition
Terra is the first satellite to provide integrated measurements of the processes connecting the atmosphere to emissions from activity on the ground. For example, Terra instruments measure both fires and smoke. In particular, Terra instruments measure aerosols (particles in the atmosphere) and carbon monoxide.
Aerosols come from a variety of sources, both natural and anthropogenic. MISR and MODIS both measure the concentration of aerosols in the atmosphere and, in some cases, provide insight into the sources of aerosol pollution. MISR can record the height of aerosol plumes in the atmosphere. Aerosols can shade the Earth by reflecting sunlight. CERES measures how much energy aerosols reflect or absorb.
While carbon monoxide (CO) is not itself a greenhouse gas, CO is chemically linked with methane, ozone, and carbon dioxide, and therefore impacts both climate and air quality. Primary sources of CO include fossil-fuel burning, biomass burning and methane oxidation. MOPITT measurements of CO concentrations in the troposphere are based on observations made with a suite of gas correlation radiometers operating in two CO-sensitive spectral bands. MOPITT CO products are used to study the movement of pollution in the atmosphere, to quantify CO emissions and to support air quality forecasts.