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Dr. Tom Loveland, who was instrumental
in establishing the first Landsat
Science Team, which he co-chairs.
A new Landsat Science Team was
recently selected and announced.
S&S How does Landsat 8 differ from
previous Landsat satellites
SABERS There are a number of significant
improvements. The operational
land imager (OLI) is a push-broom
system, which is an enhancement from
our prior instrument. It has two new
spectral bands: a blue, visible channel,
which is specifically designed for water
resources and coastal zone investigation,
and a new infrared band that we
use for detecting cirrus clouds. Those
are both significant improvements.
Also, the quality of the data has
increased, and we expect to see significant
improvement in our ability to
detect changes on the Earth’s surface.
Another improvement is that we plan
to collect at least 400 scenes a day,
which is a significant improvement
over the current Landsat mission. Not
only will the data we get be of higher
quality and more spectral depth, but
we will get much more coverage of the
entire Earth.
S&S What is your perspective on
consistency vs. improvements with
regards to Landsat products
SABERS With the Landsat products,
there is a fine balance between
consistency and improvements. Since
Landsat has been around for more
than 40 years, we are the leading
resource in being able to do longterm
Earth studies. It is essential to
maintain that consistency, so that we
can continue that longest global data
record of the Earth. So, consistency in
areas such as spatial resolution, calibration,
and spectral characterization
is extremely important. However, we
do want to take advantage of advancements
in engineering and remote
sensing, to try to ensure that we’re
getting the best data and the most data
as cost-effectively as possible for the
users and the government.
S&S Will UAS (unmanned aerial
systems) and/or microsats change the
role of Landsat
SABERS The National Research
Council hosted a workshop earlier this
year, on behalf of the USGS, to get a
sense of the current state of smallsat
technologies and how they can be
utilized for future Landsat missions.
We want to ensure that Landsat
is operational and that we have a
solid path forward. We want to take
advantage of new technologies, but
we need to assure that they are proven
and can maintain our long-term data
records and that we can maintain that
consistency. We definitely want to keep
monitoring the technology and, when
the time is right and we have confidence
in it, take advantage of it.
The approach has not yet been
decided for any mission past LDCM.
However, we want to take advantage
of any sort of future technology, as
long as we can ensure that we can get
the global coverage and the type of
imagery that we need to satisfy our
user needs. There is also potential
for UAS and microsat technology for
augmenting Landsat’s capabilities.
S&S What has been the biggest change
in Landsat during the life of the
program
SABERS It is the free archive of
Landsat data. It became freely available
several years ago and that has
revolutionized the way that scientists
study land change across the entire
planet. It has increased the types of
studies that are done and the number
of uses of Landsat data. One area in
which we’ve seen a large increase in
monitoring is evapotranspiration.
The western states, in dealing with
water rights, have used Landsat data
heavily over the past few years and
I think that it is due to the fact that
it became freely available and so the
number of applications of the data
has grown.
THERE ARE A NUMBER OF SIGNIFICANT
IMPROVEMENTS. THE OPERATIONAL
LAND IMAGER (OLI) IS A PUSH-BROOM
SYSTEM, AND IT HAS TWO NEW SPECTRAL
BANDS: A BLUE, VISIBLE CHANNEL,
WHICH IS SPECIFICALLY DESIGNED FOR
WATER RESOURCES AND COASTAL ZONE
INVESTIGATION, AND A NEW INFRARED
BAND THAT WE USE FOR DETECTING
CIRRUS CLOUDS.
S&S Do you have any final comments
SABERS Landsat is the most comprehensive
record of the global landmass
ever assembled. The Landsat archive,
going back to 1972 and continuing
into the future with LDCM, provides
an unprecedented record of the status
of the Earth’s natural resources
and human activity. The Landsat
program’s success is largely due to the
great partnership between NASA and
the USGS. I hope that we can build on
that for future missions.
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