The Smithsonian Astrophysical Observatory has been awarded a NASA project to build the Tropospheric Emissions: Monitoring of Pollution (TEMPO) instrument. TEMPO will be the first space-based instrument to monitor major air pollutants across the North American continent hourly during daytime. The instrument, to be completed in 2017 at a cost of $90 million, will share a ride on a commercial satellite to a geostationary orbit about 22,000 miles above Earth's equator.
TEMPO will measure North American air pollution, from Mexico City to the Canadian tar/oil sands, and from the Atlantic to the Pacific, hourly and at high spatial resolution. This will enable scientists to monitor daily variations in pollution amounts, and follow pollution transport. The instrument will resolve pollution levels to a region of several square miles - far better than existing limits of about 100 square miles.
"TEMPO will provide an order of magnitude improvement over our current capabilities," said Smithsonian principal investigator Kelly Chance.
Together, this temporal and spatial resolution will enable researchers to improve emission inventories, monitor population exposure, and evaluate effective emission-control strategies. It also will provide near-real-time air quality products that will be made publicly available, and will help reduce uncertainty in air quality predictions by 50 percent.
TEMPO will measure ozone, nitrogen dioxide, sulfur dioxide, formaldehyde, glyoxal, water vapor, aerosols, cloud parameters, and harmful ultraviolet radiation. These are major elements in the lower atmospheric ozone chemistry cycle. TEMPO will quantify and track the evolution of aerosol loading.
TEMPO was chosen from 14 proposals submitted to NASA's Earth Venture Instrument program. Earth Venture missions, part of the Earth System Science Pathfinder program, are small, targeted science investigations that complement NASA's larger research mission.
The TEMPO team has extensive experience in measuring the components of air quality from low-Earth orbit. Chance is on the science teams of the Ozone Monitoring Instrument, now in orbit on NASA's Aura satellite, and two European air quality space sensors. The team includes partnerships with Ball Aerospace and Technologies Corp., in Boulder, CO; NASA's Langley Research Center in Hampton, VA; NASA's Goddard Space Flight Center in Greenbelt, MD; the U.S. Environmental Protection Agency in Research Triangle Park, NC; the National Center for Atmospheric Research, in Boulder, CO; and a number of U.S. universities and research organizations.
After being deployed on a geostationary satellite, TEMPO will observe Earth's atmosphere in ultraviolet and visible wavelengths of light to determine concentrations of many key atmospheric pollutants. From geostationary orbit, these observations can be made several times each day when North America is facing the sun instead of once per day, which is the case with current satellites orbiting a few hundred miles above the surface. Other space agencies are planning similar observations over Europe and Asia concurrent with the deployment of TEMPO, forming a global constellation of geostationary air-quality satellites.