May 15 • In late April, Science
magazine reported that Brazil is a world leader in tropical
forest monitoring thanks to their use of data
from a number of Earth-observing satellites.
"Peering through the clouds." Science magazine recently
compiled this list of Earth-observing satellites used to monitor
deforestation.
Brazil's Instituto Nacional de Pesquisas Espaciais (National Institute
for Space Research, INPE) uses data from Terra's MODIS sensor to
create weekly alerts of clear-cutting activity. While annually,
INPE conducts a survey of deforestation using the higher resolution
data of the Landsat and CBERS-2 sensors. And most recently, radar
data provided by Japan's ALOS satellite have helped INPE see areas
of forest chronically covered by clouds. Researchers report
that field and satellite measurements of clear-cut areas typically
agree within 5 to 10 percent. However, substantial uncertainty
related to the amount of carbon dioxide released by these clear-cut
trees exists (errors on the order of 25% to 50%). Data fusion may
eventually help researchers better calculate the carbon emissions
associated with clear-cutting over large geographic expanses.
Note: Pioneering work on Brazil's Amazonian tropical deforestation
and its impact on habitat fragmentation was conducted by Drs. Skole
and Tucker using Landsat data. Reference can be found below.
+ Skole, D. and C. Tucker, "Tropical Deforestation and Habitat Fragmentation
in the Amazon: Satellite Data from 1978 to 1988," Science, vol.
260, June 25, 1993.