NASA is preparing for the launch of a new tool that will provide information on air quality in North America. TEMPO probe will be able to monitor climate and air pollution from space. New data will be detected more frequently and in more detail than previous tools, also identifying the disparity of different areas’ exposure to pollution.
Harmful substances to be monitored
Launch of the Tropospheric Emissions Monitoring of Pollution (TEMPO) tool, which took place in early April from Cape Canaveral, was mounted on a commercial communications satellite. It flies in an orbit that allows hourly daytime observations of air quality in North America. It observes pollutants up to a resolution of 10 square kilometers over an area that extends from the Atlantic Ocean to the Pacific and from central Canada to Mexico City. The dishwasher-sized tool was built by Ball Aerospace and will fly on the Intelsat 40E satellite built by Maxar.
Despite efforts over the last 30 years to clean up the air in the United States, over 40% of Americans still live and breathe in highly polluted areas (ref.). TEMPO will mainly observe the three main pollutants: nitrogen dioxide, formaldehyde, and ozone. Nitrogen dioxide is a harmful gas released by fuel combustion that can cause respiratory difficulties and exacerbate asthma.
Formaldehyde is a byproduct of the breakdown of volatile organic compounds such as paint, glue, and gasoline. Lastly, ozone high up in the atmosphere protects us from harmful ultraviolet rays from the sun, tropospheric ozone is a major component of smog and is harmful to vegetation and human health.
How TEMPO works
“It will be a truly valuable tool for science. But it will also be useful for the general public” said Barry Lefer, a scientist on NASA’s TEMPO program. “It will improve our ability to predict air quality and also inform policymakers. And it will be useful for epidemiologists who want to study the health impacts of air pollution”.
The tool will measure sunlight reflected from the Earth’s surface and from gases and particles in the atmosphere. That reflected light, both ultraviolet and visible, is projected onto a spectrometer that separates it into different wavelengths. Since different gases have unique fingerprints or spectra, scientists can study the wavelengths of light that are absorbed and determine the nature and quantity of gas in the atmosphere.
“Every day we receive measurements on New York City at 1:30 pm” said Caroline Nowlan, an atmospheric physicist at the Smithsonian Astrophysical Observatory. “But that’s only a part of the data on New York during the day. And we have two peak hours every day that we’re not able to capture. The great thing about the TEMPO probe instrument is its ability to monitor climate with hourly measurements across all of North America. We’ll see what’s happening all the time while the sun is up”.
TEMPO will join the Geostationary Environment Monitoring Spectrometer (GEMS) instrument aboard South Korea’s GEO-KOMPSAT-2B satellite and the upcoming Sentinel-4 from the European Space Agency (ESA) to form a wider constellation of satellites monitoring air quality in Europe and Asia.