|
NEW NASA/CSA
MONITOR PROVIDES GLOBAL
AIR POLLUTION VIEW FROM
SPACE
All photos
courtesy: NASA/NCAR/CSA
The most complete view ever
assembled of the world's air pollution churning through the
atmosphere, crossing continents and oceans, has been produced
by NASA's Terra spacecraft. For the first time, policymakers
and scientists now have a way to identify the major sources of
air pollution and can closely track where the pollution goes,
anywhere on Earth.
The new global air pollution
monitor onboard Terra is the innovative Measurements of
Pollution in the Troposphere, or MOPITT experiment, which was
contributed to the Terra mission by the Canadian Space Agency.
The instrument was developed by Canadian scientists at the
University of Toronto and built by COM DEV International of
Cambridge, Ontario. The data was processed by a team at the
U.S. National Center for Atmospheric Research (NCAR). MOPITT
is making the first long-term global observations of the air
pollutant carbon monoxide as Terra circles the Earth from pole
to pole, 16 times every day.
"With these new
observations you clearly see that air pollution is much more
than a local problem. It's a global issue," said John
Gille, MOPITT principal investigator at NCAR in Boulder, CO.
"Much of the air pollution that humans generate comes
from natural sources such as large fires that travel great
distances and affects areas far from the source."
The first MOPITT observations
are being released at the annual American Geophysical Union
spring meeting in Boston, MA.
The most dramatic features,
taken from last year from March to December, are the immense
clouds of carbon monoxide from grassland and forest fires in
Africa and South America. The plumes slowly travel across the
Southern Hemisphere as far as Australia during the dry season
in this part of the world.
Gille was surprised to discover
a strong source of carbon monoxide in Southeast Asia. The air
pollution plume from this region moves over the Pacific Ocean
and reaches North America, frequently at fairly high
concentrations, according to Gille. While fires are the major
contributor to these carbon monoxide plumes, he suspects, at
times, industrial sources may also be a factor.
 |
What the colors mean --These measurements show concentrations of carbon monoxide (CO) at
altitudes of 15,000 feet. Red colors in these images indicate highest levels of CO (450 parts per billion). Blue colors indicate lowest
levels of CO (50 ppb). Terra sees CO in the atmosphere from 2-3 miles
above the surface, where it interacts with other gases and forms
ozone. This pollutant can move upward to altitudes where it can be
blown rapidly for great distances or it can move downward to the
surface. CO is an air pollutant that also produces ozone, a greenhouse gas that is a human health hazard. The data are combined
with wind measurements to produce the final image sequences.
(LEFT) Terra detected strong sources of CO in Southeast Asia during April and May 2000. The air pollution plume from this region moves over the Pacific Ocean and reaches North America, frequently at fairly high concentrations. Scientists say that
fires and possibly industrial sources are major contributors to these events.
Click
here for an animation
of the stills above
(Caution: File is 5.63 MB)
|
 |
 |
 |
|
|
"The MOPITT
observations represent a powerful new tool for identifying
and quantifying pollution sources and for observing the
transport of pollution on international and global
scales," said atmospheric chemist Daniel J. Jacob,
Harvard University, Cambridge, MA, who used MOPITT data this
spring in a major field campaign to study air pollution from
Asia. "Such information will help us improve our
understanding of the linkages between air pollution and
global environmental change, and it will likely play a
pivotal role in the development of international
environmental policy."
MOPITT also
captured the extensive air pollution generated by the forest
fires in the western United States last summer. A major
source of air pollution during the wintertime in the
Northern Hemisphere is the burning of fossils fuels for home
heating and transportation, which can be seen wafting across
much of hemisphere.
Although MOPITT
cannot distinguish between individual industrial sources in
the same city, it can map different sources that cover a few
hundred square miles. This is accurate enough to
differentiate air pollution from a major metropolitan area,
for example, from a major fire in a national forest. About
half of the global emissions of carbon monoxide are caused
by human activities.
Carbon monoxide
is not only a hazardous air pollutant itself, it is also a
chemical compound that produces ozone, a greenhouse gas that
is a human health hazard. MOPITT sees carbon monoxide in the
atmosphere from 2 to 3 miles above the surface, where it
interacts with other gases and forms ozone. This pollutant
can move upward to altitudes where it can be blown rapidly
for great distances or it can move downward to the surface.
Carbon monoxide
is a byproduct of the incomplete burning of fossil fuels by
cars, industry, and home heating and the burning of natural
organic matter such as wood. By tracking plumes of carbon
monoxide, scientists are able to track the movements of
other pollutants such as nitrogen oxides that are also
produced by the same combustion processes but cannot be
directly detected from space.

Click
here for an animation
of the stills above
Caution -- file is 5.63
MB
Much of the air pollution that humans generate comes from natural
sources such as smoke from large fires that travel great distances
and affects areas far from the source. The most dramatic features in
the first set of MOPITT global observations from March to December
2000 are the immense clouds of carbon monoxide from grassland and
forest fires in Africa and South America. The plumes travel rapidly
across the Southern Hemisphere as far as Australia during the dry
season in this part of the world.

Click
here for an animation
of the stills above
-
Full flat earth -- Caution -- File is 5.63 MB
The swirling colors in these images paint a remarkable new portrait
of our planet. For the first time, scientists have a powerful new
tool to track immense clouds of air pollution, shown in red, as they
travel across the Earth. The observations represent a powerful new
tool for identifying and quantifying pollution sources and for
observing the transport of pollution on international and global
scales.
Click
here for a full animation
of the 3D globe
Caution -- File is 11.2
MB
The most complete view ever assembled of the world's air pollution
churning through the atmosphere and crossing continents and oceans
has been produced by the MOPITT (Measurements of Pollution in the
Troposphere) instrument on NASA's Terra spacecraft.
|