Data from NASA’s Terra satellite is adding to our
understanding of how pollution spreads around the globe. The
information will help scientists protect and understand the
Earth.
NASA funded scientists from the National Center for
Atmospheric Research (NCAR), Boulder, Colo., will present two
studies focusing on global air pollution. Their presentations
are part of the 2004 Joint Assembly of the American and
Canadian Geophysical Unions.
David Edwards will discuss “Observations of Carbon Monoxide
and Aerosol from the Terra Satellite: Northern Hemisphere
Variability,” on Thursday at 8:45 a.m. EDT in room 520D of
the Palais des Congres, Montreal. Cathy Clerbaux will
discuss, “Tracking of Pollution Plumes Using Measurements of
Pollution in the Troposphere (MOPITT) Measurements,” at 9:30
a.m. EDT.
Both studies used instruments on NASA’s Terra satellite to
examine trends in global carbon monoxide (CO) and fine
particulate (aerosol) pollution. Industry and vehicles in
urban regions and fires produce these pollutants.
Terra and other NASA Earth observing satellites provide vital
tools for monitoring global levels, sources and destinations
of CO and other pollutants. The growing data record shows
seasonal and annual variations, clues about how our planet
may be changing. CO molecules can last from a few weeks to
several months in the atmosphere, allowing them to travel
long distances and impact air quality far from the point of
emission.
Edwards, an NCAR researcher, used two sensors on NASA’s Terra
to track CO and aerosols from smoke originating in Russia.
The plumes were tracked as they spread across the Pacific
Ocean, filling the Northern Hemisphere.
In late summer 2002 and spring 2003, Terra observed big fires
in western Russia and Siberia. The fires led to a ‘dirty’
2002/03 winter atmosphere in the Northern Hemisphere with
high amounts of CO and aerosol. Peak levels of CO hung over
the United States.
By using two complementary instruments on Terra, Edwards was
able to tell the difference between pollutants originating
from wildfires and those from urban and industrial sources.
The MOPITT instrument provided CO data, while the Moderate-
resolution Imaging Spectroradiometer (MODIS) instrument
recorded aerosol data.
“The satellite observations showed Russian fires have a huge
impact on air quality on a global scale,” Edwards said. “This
work helps get the message across, that when it comes to
pollution, we need to think globally,” he added.
Work has started to see if the MOPITT instrument can track CO
pollution originating from cities. Clerbaux, a scientist
visiting NCAR from the French National Center for Scientific
Research, points out tracking pollution from cities is very
important, since half the people on Earth will live in urban
centers by 2007.
Though MOPITT was not designed specifically to detect
pollution plumes from cities, the results look promising. By
selecting the data and averaging it over long time periods,
the observations were made more reliable, and help
distinguish the city emissions from other distant sources.
MOPITT data shows how wildfires in Kalimantan on Borneo
Island in Indonesia, contaminated the air in 2002 above
Jakarta, Indonesia. “The instrument also shows how pollution
gets dispersed from cities,” Clerbaux said. “Mexico City and
Jakarta are both surrounded by mountains. Due to topography,
Terra revealed pollution could only escape upward or through
openings in the landscape. For example, like the area to the
north for Mexico City,” she added.
NASA’s Earth Science Enterprise is dedicated to understanding
the Earth as an integrated system and applying Earth System
Science to improve prediction of climate, weather, and
natural hazards using the unique vantage point of space.
For information and images about this research on the
Internet, visit:
