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NASA launched on Friday, April 7, an instrument that will provide new insight into air quality in North America. The Tropospheric Emissions Pollution Monitoring Instrument (TEMPO) will observe air pollution from space with greater frequency and detail than previous space instruments. It will also shed light on inequalities in pollution exposure.
Launched from the Cape Canaveral Space Force Station, TEMPO lifted off aboard a commercial communications satellite and will fly in an orbit that allows air quality observations to be made every hour during the day in North America. It will observe pollutants down to a resolution of 10 square kilometers (4 square miles) and over an area stretching from the Atlantic Ocean to the Pacific Ocean and from central Canada to Mexico City. The instrument, which is the size of a dishwasher, was built by Ball Aerospace and travels aboard the Intelsat 40E satellite built by Maxar.
Although efforts over the past 30 years to clean dirty air from smokestacks and tailpipes have improved air quality in the United States, more than 40% of Americans still live and breathe in areas with episodes. of poor air quality.
TEMPO will be the first instrument to monitor the major air pollutants from space at high spatial resolution every hour in North America, from Mexico City to the Canadian oil sands and from the Atlantic Ocean to the Pacific Ocean.
Credits: NASA
TEMPO will essentially look at three main pollutants: nitrogen dioxide, formaldehyde, and ozone. Nitrogen dioxide is a noxious gas released by burning fuel that can cause breathing difficulties and exacerbate asthma. A byproduct of the breakdown of volatile organic compounds in paint, glue and gasoline, formaldehyde has health effects ranging from eye irritation to cancer. And while ozone high in the atmosphere protects us from the Sun’s damaging ultraviolet rays, ozone at ground level is one of the main components of smog and is detrimental to vegetation and human health.
“This will be a very valuable tool for science, but it will also be useful for the general public,” said Barry Lefer, NASA TEMPO program scientist. “It will improve our ability to forecast air quality and also to inform policymakers. And it will be useful for epidemiologists who want to study the health impacts of air pollution.”
This instrument will measure the sunlight that is reflected by the Earth’s surface and by 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 signals, or distinctive spectra, scientists can study the wavelengths of light that are absorbed and determine the nature and amount of gases found in the atmosphere.
NASA scientists have been collecting measurements of air pollution from low Earth orbit for more than two decades. Those satellites have flown in polar orbits about 760 kilometers (470 miles) above the surface and make observations of most places on the planet about once a day.
“We’ve been getting these measurements over New York City daily at 1:30 p.m.,” said Caroline Nowlan, an atmospheric physicist at the Smithsonian Astrophysical Observatory, which is part of the Harvard Center for Astrophysics and the Smithsonian Institution in Cambridge. , Mass. “But that’s just one data point over New York per day. And every day we have two rush hours [de gran congestión de tráfico] that we cannot capture.
TEMPO and the satellite it travels on will fly at the same speed that the Earth rotates and at a fixed point on the equator, in a position known as a geosynchronous orbit. This orbit, combined with the satellite’s location in the Western Hemisphere, will allow the instrument to focus on North America, scanning from the East Coast to the West Coast and providing detailed measurements of the entire continent during daylight hours.
“The great thing about TEMPO is that, for the first time, we will be able to take measurements over North America once an hour,” Nowlan said. “We will be able to see what is happening all the time as the Sun shines.”
Thanks to TEMPO’s geostationary orbit and spatial resolution, its data will also shed light on how pollution varies in each neighborhood within a city.
This will allow people to use the data to investigate environmental justice issues, according to John Haynes, applications director for the TEMPO program at NASA Headquarters in Washington. “We know that oil refineries or chemical plants tend to be located in low-income neighborhoods; And one of the reasons property values are lower is due to poor air quality. But we’ve never had ground monitors located in every neighborhood to confirm it.” With TEMPO, Haynes explained, it will be possible to show these differences and inequities in all major North American cities.
TEMPO will join the Geostationary Environmental Monitoring Spectrometer (GEMS) instrument aboard South Korea’s GEO-KOMPSAT-2B satellite and the upcoming European Space Agency (ESA) Sentinel 4 satellite. English) to form a larger constellation of satellites that will also monitor air quality in Europe and Asia.
Kelly Chance, a scientist at the Smithsonian Astrophysical Observatory, is the principal investigator for TEMPO. The project team is based at the NASA Langley Research Center in Hampton, Virginia, and the data will be distributed by the NASA Atmospheric Sciences Data Center, also in Langley.
TEMPO will join the Geostationary Environmental Monitoring Spectrometer (GEMS) instrument aboard South Korea’s GEO-KOMPSAT-2B satellite and the upcoming European Space Agency (ESA) Sentinel 4 satellite to form a larger constellation of satellites that will also will monitor air quality in Europe and Asia.
Credits: NASA/Tim Marvel
Jenny Marder
NASA Earth Science News Team