Researchers from around the globe participating in the
world’s largest environmental science experiment, the Large-
Scale Biosphere Atmosphere Experiment in Amazonia (LBA),
will, fittingly, convene in Brazil this week.

From July 27-29, some 800 researchers will attend the Third
International Scientific Conference of the LBA in Brasilia,
Brazil, to discuss key findings on how the world’s largest
rainforest impacts the ecological health of Amazonia and the
world. Never before has so much information about the Amazon
been assembled for presentation at once.

LBA is partly funded by NASA. Also, scores of projects that
feed the Amazon experiment depend heavily on NASA’s vast
expertise in satellite information, computer modeling, and
providing infrastructure for large-scale field campaigns.

The overall experiment concentrates on how the Amazon forest
and land use changes within the region affect the atmosphere,
and regional and global climate. In turn, LBA also studies
how climate changes influence the biological, chemical and
physical functioning of the forest itself.

Topics discussed at the conference will include: the carbon
cycle, the water cycle, human land use, ecosystem processes
and human health, agricultural applications, and other topics
relating to the Amazon. The conference will also allow
researchers and Brazilian policy makers to discuss ways to
use LBA results to create public policies for the Amazon
region that foster a healthy environment and provide for
sustainable development.

NASA plays a key role in LBA research. Satellites provide
data for studying land use changes and their impacts on
climate. Scientists hope to learn more about the Amazon
forest’s role in sequestering carbon from the atmosphere.
Atmospheric carbon dioxide (CO2) traps heat and adds to
global warming. Plant life absorbs CO2 from the air during
photosynthesis and stores it in stems, leaves and roots. In
order to understand regional and global carbon balances,
researchers must quantify how much carbon is taken up by the
rainforest as well as how much is released back to the
atmosphere when forests are cleared or burned.

In the Amazon, deforestation, selective logging, fires and
forest re-growth all play major roles in the carbon balance.
In the Brazilian Amazon region alone, annual clear-cutting
and burning of forests cover about 20,000 square kilometers
(7,700 square miles or about the area of New Jersey). NASA
data products from various instruments on the Landsat series
of satellites have documented the history of deforestation in
the Amazon since the 1970s. LBA researchers have found ways
to measure both logging area and logging damage using Landsat
and experimental new sensors on NASA’s EO-1 satellite.

Ecosystem models and NASA’s Moderate Resolution Imaging
Spectroradiometer (MODIS) instrument aboard the Terra and
Aqua satellites have helped scientists understand how the
exchange of carbon between the forest and atmosphere differs
over the course of the year. Also, LBA studies have found
forest uptake of CO2 is not enough to keep pace with carbon
that is returned to the atmosphere when forests are cut.

Burning practices to clear fields for farming often result in
fires spreading to adjacent forests. These large fires create
air pollution and can contribute to respiratory problems in
people. Thick smoke has forced airports to close, and has
caused highway accidents. Satellite retrievals of
concentrations of airborne particles from NASA’s MODIS
instrument have been used by Brazil’s Center for Weather
Prediction and Climate Studies to create models that can
predict fire risk and smoke transport in near-real time.

Satellite data also help scientists study how particles from
fires impact climate and weather. These particles, known as
aerosols, can both heat and cool the air, depending on size,
shape and color.

Scheduled to end in 2006, LBA is considered an international
scientific success, with 61 projects completed and 59 in
progress. The efforts include more than 1,000 researchers
from institutions in Brazil, the United States, eight
European countries and several other countries of the Amazon
Basin (Venezuela, Peru, Bolivia, Colombia and Ecuador). LBA
is financed by Brazilian funding agencies, NASA and the
European Union.

For information and images about this research on the
Internet, visit:
http://www.gsfc.nasa.gov/topstory/2004/0727lba.html