Transcripts of G2012-101_LDCM_Overview

Jim Irons: The data from the Landsat Data Continuity Mission will be the best data that have ever been collected from a Landsat satellite. With increasing population, our land uses are changing at a rate that is unprecedented in human history. To manage and cope with these changes, we need to have the observations, the information, the data that allow us to understand what's going on on the surface of the earth where most of us live. Narrator: Landsat's been monitoring the surface of the earth since 1972, tracking resources like farms, forests, and water. And checking every continent, every season, every year. Well, we don't call it the "Data Continuity Mission" for nothing. Doug Morton: The Continuity of those observations is a really critical part of the ability to do the science we do on how climate change and how land use are transforming our planet. The Landsat program and the duration of the Landsat time series is the only record we have of these fundamental changes in land cover including melting glaciers, including loss of tropical forests, including the transformation from small-scale family agriculture to large agribusiness. Narrator: After launch, LDCM will become known as Landsat 8, since it's the 8th in the Landsat program. a partnership between NASA and the U.S. Geological Survey. NASA is responsible for building and launching a satellite and the Geological Survey is in charge of operations and receiving and archiving the data. LDCM carries two instruments, each covering a different past of the electromagnetic spectrum. Del Jenstrom: The OLI instrument monitors the Earth's surface in spectral wavelengths that you and I can see in, that's the visible wavelengths, and also in – just into the infrared regions, the near-infrared and shortwave-infrared regions. Narrator: The Operational Land Imager is used to track urban sprawl, forest loss and regrowth, changes in farm land, and the melting of glaciers. The Thermal Infrared Sensor instrument, TIRS, monitors the Earth in thermal bands which are – actually images temperature on the Earth's surface. Narrator: With TIRS, scientists are able to track how much water is used by crops on individual farm fields. And the new technology used in LDCM means that both TIRS and OLI will be much more sensitive than previous Landsat sensors. Jenstrom: The greatest improvement we've made in the LDCM satellite is that the sensors are what's called push-broom sensors and not what was called whisk-broom sensors. Push-broom sensors have thousands of detectors that just image the earth as the satellite passes over the surface of the Earth. The older Landsat satellites, Landsat 7, Landsat 5, use a whisk-broom technology which is many fewer detectors, scanning back-and-forth with a mechanical scanner. Irons: The advantage of the push-broom is each detector has a longer time to dwell on each picture element, or pixel on the surface of the Earth. As a consequence, it creates a sensor with a much higher sensitivity, expressed as signal-to-noise ratio. Voice over: T-minus 5 4, 3, 2, 1, and Liftoff! Jenstrom: The LDCM observatory launches out of the Vandenburg Air Force Base in California and launches into what's called a polar orbit. And so it orbits over the north and south poles, taking imagery of the sunlit side of the Earth every time it passes. Narrator: It takes about 100 minutes to loop around the poles. LDCM will make 14 orbits each day, and cover the whole globe every 16 days. Every time they pass over the US, Landsat satellites beam data to the USGS Earth Resources Observation and Science Center, or EROS, in South Dakota, one of several receiving stations around the world. Irons: This center operates the Landsat archive that contains all of the US held data from all of the Landsat satellites, and the LDCM data will become part of that archive. Narrator: All of the data in the Landsat archive can be obtained by anyone, at no cost. This freely available data has led to an incredible blossoming of science research and applications. Morton: My favorite part of the Landsat program is the opportunity to think big. With free and open access to data around the world, we're not limited as we once were in our ability to conceive of and analyze large data sets, to look at really large scale changes, over continents, over the globe. [music] [beeping]