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From monitoring croplands in Arizona to mapping ice streams in the Antarctic, Landsat 7 will advance earth science research.

March 1999 Science Writers’ Guide to Landsat 7

NASA’s Earth Observing System

The Earth Observing System (EOS), the centerpiece of NASA’s Earth science program, is a suite of spacecraft and interdisciplinary science investigations dedicated to advancing our understanding of global change. The flagship EOS satellite, Terra (formerly EOS AM-1), scheduled for launch in July 1999, will provide key measurements of the physical and radiative properties of clouds; air-land and air-sea exchanges of energy, carbon, and water; trace gases; and volcanoes. Flying in formation with Terra, Landsat 7 will make global high spatial resolution measurements of land surface and surrounding coastal regions. Other upcoming EOS missions and instruments include QuikSCAT, to collect sea surface wind data; the Stratospheric Gas and Aerosol Experiment (SAGE III), to create global profiles of key atmospheric gases; and the Active Cavity Radiom- eter Irradiance Monitors (ACRIM) to measure the energy output of the Sun. The second of the major, multi-instrument EOS platforms, PM-1, is scheduled for launch in 2000. Interdisciplinary research projects sponsored by EOS use specific Earth science data sets for a broader investigation into the function of Earth systems. Current EOS research spans a wide range of sciences, including atmospheric chemistry, hydrology, land use, and marine ecosystems. The EOS program has been managed since 1990 by the Goddard Space Flight Center in Greenbelt, Md., for NASA’s Office of Earth Science in Washington, D. C. Additional information on the program can be found on the EOS Project Science Office Web site (http://eospso.gsfc.nasa.gov). Science Writers’ Guide to Landsat 7

Evolution of the Landsat Program

Landsat is the United States’ oldest Company (EOSAT) took over operation land-surface observation satellite in 1985 and was given rights to market system. Although the program has Landsat data. scored numerous successes in scientific Landsat 5 was launched in March and resource-management applications, 1984 and is still returning images. Landsat has had a tumultuous history Landsat 6, which was commercially built of management and funding changes and managed, was destroyed after over its 26-year history. Landsat 7 marks launch in October 1993 when the a new direction in the program to rocket’s upper stage failed to fire. reduce the costs of data and increase With the passage of the Land global coverage for use in global change Remote Sensing Policy Act in 1992, research. oversight of the Landsat program began The diversity of Landsat applica- to shift from the commercial sector to the tions makes it unique among Earth federal government. Management was observation satellites. Images acquired transferred from NOAA to NASA and by Landsat satellites were used to the Department of Defense. President produce the first composite multi- George Bush authorized Landsat 7 in the spectral mosaic of the 48 contiguous same year. The Department of Defense United States. They have been used to withdrew from the program in 1994, and monitor timber losses in the U.S. Pacific NASA was named the lead agency Northwest, map the extent of winter working with NOAA and the U. S. snow pack, and measure forest cover at Geological Survey (USGS). the state level. In addition, Landsat has NASA integrated Landsat 7 into its been used in to locate mineral deposits, EOS program in 1994. The agency is monitor strip mining, and assess natural responsible for the development and changes due to fires and insect infesta- launch of the satellite, and the develop- tions. ment of the ground system. As the NASA launched the first satellite in operational era begins, Landsat 7 is the Landsat series (originally called the transitioning to a dual-agency program Earth Resources Technology Satellites) between NASA and USGS. Future on July 23, 1972. The program was given management will be governed by a joint the name Landsat in 1975. Efforts to agreement between the two agencies. move the Landsat program into the As part of NASA’s EOS series of commercial sector began under the satellites, Landsat 7 will provide a Carter Administration in 1979 and unique suite of high-resolution observa- resulted in legislation passed in 1984 tions of the terrestrial environment. that charged the National Oceanic and While other sensors onboard the Terra Atmospheric Administration (NOAA) satellite, to be launched in July 1999, will to transfer the program to the private characterize daily changes at coarse sector. The Earth Observing Satellite resolution, Landsat will provide data at 1 Science Writers’ Guide to Landsat 7

a finer resolution to allow for investiga- The Landsat 7 system will collect tions of the causes of land-surface and archive an unprecedented quantity change. of high-quality multispectral data each Landsat 7 will gather remotely day. This dataset will, for the first time, sensed images of land surface and provide a high-resolution view of both coastal regions for global change re- seasonal and interannual changes in the search, regional environmental change terrestrial environment. The USGS Earth studies, national security uses, and other Resources Observation Systems Data civil and commercial purposes. The Center (Sioux Falls, SD) will process, Landsat 7 project is part of NASA’s long archive, and distribute all U.S. Landsat term, coordinated research effort to data. U.S. data will be acquired prima- study the Earth as a global environmen- rily at the EROS Data Center; supporting tal system. ground stations in Alaska and Norway The Landsat Science Team, com- will also be used. posed of 14 scientific investigators, was The Landsat Project, located at selected in 1996. These researchers are Goddard Space Flight Center (Greenbelt, conducting a range of studies designed Md.), manages Landsat development for to exploit the characteristics of Landsat 7 NASA’s Office of Earth Science in for global change research. The satellite Washington, D.C. USGS operations will will fly in near-formation with Terra, be performed at a Mission Operations observing the same ground track just a Center at the Goddard Space Flight few minutes apart. Landsat 7 will Center and at the EROS Data Center. capture and store in a U. S. archive global landmass data once per season. Following an initial 60-70 day checkout period, Landsat 7 will begin normal operations. Daily commands will be sent to the spacecraft defining which images to record and when to downlink data either to U.S. or interna- tional ground stations. NASA will continue to manage day-to-day opera- tions until October 2000, when they will be turned over to USGS.

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A New Era of Landsat Technology

The instrument on board Landsat 7 when a user requested it instead of as an is the Enhanced Thematic Mapper Plus ongoing process, which is essential to (ETM+). ETM+ is a passive sensor that scientific studies. Landsat 7’s commit- measures solar radiation reflected or ment to collecting and archiving all emitted by the Earth’s surface. The scenes in the United States including instrument has eight bands sensitive to Alaska and Hawaii is a significant different wavelengths of visible and change in the program. infrared radiation and has better resolu- Processing, distributing, and tion in the thermal infrared band than archiving Landsat data will also be the Thematic Mapper (TM) instrument significantly improved. Previous carried by Landsats 4 and 5. The Landsat data was often too expensive for instrument’s calibration is good to widespread scientific use. All Landsat 7 within 5 percent, making the ETM+ far data received at the USGS EROS Data more accurate than its predecessors. Center receiving station will be archived Landsat 7 data will be used to build and available electronically within 24 and periodically refresh a global archive hours and will be sold at cost. In addi- of Sun-lit, essentially cloud-free images tion to the main U.S. receiving station, of the Earth’s landmass. With an up- several international ground stations graded data system on the ground, will collect Landsat 7 data around the Landsat 7 will collect 250 scenes per day, globe, archive it, and make it available each scene containing enough digital through on-line Internet browsers. Steps data to fill a powerful home computer’s are being taken to link the browsers and hard drive. The Landsat 7 receiving give users a single point of entry to the station will handle 4-5 times more data network and easy access to Landsat than the existing program’s receiving catalog information. station. During the Landsat program’s management as a commercial operation, it became increasingly expensive to gather data. As a cost saving measure, Landsat imagery was only collected

3 Science Writers’ Guide to Landsat 7

Launch and Mission Profile

Launch of Landsat 7 is scheduled After being launched into a sun- for April 1999 from the Western Test synchronous polar orbit, the satellite will Range at Vandenberg Air Force Base, use on-board propulsion to adjust its Calif., on a Delta-II expendable launch orbit to a circular altitude of 438 miles vehicle. The Landsat 7 satellite consists (705 kilometers) crossing the equator at of a spacecraft bus being provided by approximately 10 a.m. on its southward Lockheed Martin Missiles and Space track. This orbit will place Landsat 7 (Valley Forge, PA) and the Enhanced along the same ground track as previous Thematic Mapper Plus instrument built Landsat satellites. The orbit will be by Raytheon (formerly Hughes) Santa maintained with periodic adjustments Barbara Remote Sensing (Santa Barbara, for the life of the mission. A three-axis Calif.). attitude control subsystem will stabilize Continuity of data with previous the satellite and keep the instrument Landsat missions is a fundamental goal pointed toward the Earth to within 0.05 of the Landsat program. To accomplish degrees. this, images will be taken that are Daily commands will be sent to the consistent in terms of data acquisition spacecraft defining which images to format, geometry, spatial resolution, record and when to downlink data either calibration, coverage characteristics, and to U. S. or international ground stations. spectral characteristics with previous Landsat data. Landsat 7 will image large areas of the sunlit Earth daily, revisiting the same areas every 16 days to refresh a global archive. Digital copies of all images in the archive will be available to users for the cost of fulfilling the re- quest. At launch, the satellite, including the instrument and fuel, will weigh approximately 4,800 pounds (2,200 kilograms). It is about 14 feet long (4.3 meters) and 9 feet (2.8 meters) in diam- eter.

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Research Profiles

Volcanic hazards and lava lakes

Luke Flynn, University of Hawaii

To understand the complex “plumb- surface. Using similar Landsat data, ing” beneath active volcanic lave lakes Flynn produces maps of the leading and determine the amount of lava edges of wildfires. flowing from them, Luke Flynn of the Flynn and Harris have also been Active lava University of Hawaii has been using working with Landsat data of active time series of Landsat images. Much of volcanic lava lakes around the world. In flows can be his work has focused on the persistence addition to their work in Hawaii, they distinguished of volcanic eruptions at Hawaii’s are studying long-term observations of Kilauea volcano, which has been con- eruptions in Mexico (Popocatepetl) and from older flows tinually erupting since 1983. Another Guatemala (Santa Maria and Pacaya). objective of Flynn’s research – and one Once they have compiled extensive that have critical to many residents of Hawaii – is observations of an individual volcano, already begun to map active lava flows and provide they create a database of areas on the advance warning to public safety volcano that are most prone to lava flow to cool. officials about these natural hazards. hazards. Flynn plans to produce even Flynn and other volcanologists have higher resolution maps of active lava been using remote-sensing data from the flows (15 m) with Landsat 7. geostationary GOES satellite to monitor Flynn plans to collect Landsat 7 data volcanic eruptions in remote areas in at a ground station in Hawaii as the real time. The higher resolution of satellite passes over the state. He plans Landsat data (30 meters as compared to to produce new Landsat 7 volcano (and 4 kilometers for GOES) can produce wildfire) hazard maps for the State of maps of lava flows with pinpoint Hawaii every 8 days. accuracy, according to Flynn. With these maps researchers can study the evolu- Contact information: Luke Flynn, Hawaii tion of individual eruptions while they Institute of Geophysics and Planetology/ are taking place. School of Ocean and Earth Science Technol- With Landsat observations of the ogy, University of Hawaii, tel. 808-956- heat emitted during eruptions, Flynn 3154; [email protected]. can distinguish active lava flows from University of Hawaii Public Information older flows that have already begun to Office, Florence Donne, tel. 808-956-7522; cool. With this data, Flynn’s colleague [email protected]. Andrew Harris is generating estimates of the amount of lava erupting onto the

5 Science Writers’ Guide to Landsat 7

Growth patterns of urban sprawl

Jeffrey G. Masek, University of Maryland

Traffic jams and air pollution in Observing urban areas over time large metropolitan areas are sure signs with satellite imagery can also be used of expanding populations. Across the to make predictions about future globe, 50 percent of the world’s popula- growth. Landsat imagery can show tion now lives in urban areas, a gain of where the growth is taking place and over one billion individuals in the last help geographers evaluate how different 30 years. In the United States, urban urban planning programs effect popula- How do zoning growth can be counted in a census, but tion growth and land use, according to policies and how do these expanding populations Masek. Cities such as Portland, Ore., affect the landscape? Are urban areas have strict planning and environmen- environmental making good use of limited space or are tally sensitive zoning laws, while many pressures they succumbing to urban sprawl? How Southwestern cities have grown with do factors like zoning policies and few planning guidelines. influence the environmental pressures influence the With Landsat 7 observations, Masek expansion of expansion of populations over the land? and colleagues intend to evaluate Jeffrey Masek and Frank Lindsy, growth patterns of other cities around urban geographers from the University of the world. With a greater number of Maryland, are using Landsat data to images available, Masek can compare populations? study land use efficiency, which is the cities once every two years to capture amount of land area used by increasing detailed records of land use changes. populations. Using Landsat data ac- quired between 1973 and 1996, Masek Contact information: Jeffrey G. Masek, and Lindsy mapped the growth of the Department of Geography, University of Washington D.C. metropolitan area. Maryland; tel. 301-405-8233; They found that the Washington [email protected]. area has expanded at a rate of 8.5 square University of Maryland Office of University miles (22 square kilometers) per year Relations, Lee Tune, tel. 301-405-4679; with notably higher growth during the [email protected]. late 1980s, a trend that followed the regional and national economy. They also found distinct variations in the efficiency of land use among neighbor- ing counties in Maryland and Virginia, in part reflecting the land use policies of these jurisdictions.

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“Dune reactivation” in the U. S. High Plains

Alexander F. H. Goetz, University of Colorado at Boulder

More than 10 percent of the United pivot irrigation since 1985. Some of the States’ High Plains region is made up of pivots are located in the dune areas and sand dunes and sand sheets that are these spots would become dune reacti- currently stabilized by the natural vation sites if the irrigation were discon- grasses growing on them and by irri- tinued, according to Goetz. gated farming. If future climate change Combining land-cover data with leads to increased temperatures and less meteorological and future climate data rainfall in this arid region, as some in a regional climate model, Goetz plans Some climate climate models predict, these sandy to produce a model-based method for models predict landscapes could be “reactivated” and estimating future dune reactivation and begin blowing as they did in the “dust identifying the areas with the highest these sandy bowl” years of the 1930s. potential for reactivation. The team will landscapes Information about the dunes in this also investigate the potential effect of 800,000 square-kilometer region – abandoning farmed and irrigated lands could begin encompassing parts of Colorado, South on dune reactivation. blowing as they Dakota, Nebraska, Kansas, Oklahoma, Landsat 7 data will provide the Texas, and New Mexico – has been researchers with many more images did in the “dust available for decades. However, a than are currently available, since the bowl” years. systematic study of the relationship team will acquire images from every between humans and the land and land- pass of the satellite over the region. With use change on a large geographic scale multiple images during a growing is only now possible utilizing satellite season, they can more precisely distin- observations. guish crop types and change. Goetz Alexander Goetz, professor of expects that by extending the Landsat geological sciences at the University of dataset beyond 2000, he will be able to Colorado is leading a research team to catch a significant drought year, which create an effective way to assess how the will help to validate models for the High Plains will be affected by future effect of low rainfall in the High Plains. climate change. Using Landsat 5 data from 1984 to the present, Goetz’ team Contact information: Alexander F. H. Goetz, has completed a detailed study of land Director, Center for the Study of Earth from cover change in northeastern Colorado Space, Cooperative Institute for Research in and is creating a 15-year database of Environmental Sciences, University of land cover and human-induced land Colorado, tel. 303-492-5086; cover changes in the region. [email protected]. One of the more striking observa- Office of Public Relations, Jim Scott, tel. tions is the dramatic shift from dry-land 303-492-3114; [email protected]. farming and flood irrigation to center-

7 Science Writers’ Guide to Landsat 7

Spring run-off contaminants in lakes

John Schott, Rochester Institute of Technology

As snow begins to melt at the close synoptic perspective, and high resolu- of winter, large lakes receive warm tion is a unique asset that may be used spring river run-off carrying pollutants to further understand the water quality that are potentially harmful to phy- issues affecting Great Lakes coastal toplankton and the fish that feed on waters. them. The warmer water initially stays Schott’s work may eventually be near the shoreline, not mixing with the helpful in understanding how the In large lakes the cold winter lake water. Salt, sediment, release of industrial pollutants into the “thermal bar” fertilizer and chemical pollutants in the Genesee and Niagara rivers during the run-off are concentrated in a small band thermal bar formation in Lake Ontario can become of warmer water close to the shore called effect the lake’s ecosystem. Thermal bar potentially toxic the thermal bar. By June, the lake’s formation occurs during the spring waters are well mixed, and pollutants when plants and animals in the lake are to plants and brought into the lake are very dilute. in the early stages of development. Most lakes in regions that have cold animals. Schott and his research team are winters and warm summers have an using Landsat data to determine how annual episode of thermal bar forma- large-scale hydrodynamic processes in tion. But only in large lakes does the the Great Lakes control water quality. thermal bar persist for two months and The thermal bar formation is modeled become potentially toxic to lake plants using Landsat data and three-dimen- and animals. sional hydrodynamic models. Eventu- John Schott, of the Rochester Insti- ally, the models will track the annual tute of Technology’s Digital Imaging and evolution of the thermal bar and attempt Remote Sensing Laboratory, is using to predict the bar’s formation several Landsat imagery to help predict the months in advance. extent, duration, and impacts of the thermal bar formation in the Laurentian Contact information: John Schott, Rochester Great Lakes. For the two months that the Institute of Technology, Digital Imaging and bar persists, it controls most of the fluid Remote Sensing Laboratory, tel. 716-475- flow in the lakes and has a dramatic 5170; [email protected]. impact on water quality. Landsat offers University News Service, Kathy Lindsley, the unique opportunity to study both the tel. 716-475-5061; [email protected]. thermal bar processes and the direct impact on the water quality at both whole lake scales and localized scales. The combination of spectral coverage,

8 Science Writers’ Guide to Landsat 7

Land use in tropical rain forests

David Skole, Michigan State University

Even though tropical deforestation and rates of land cover change. The is a well-known problem, the rate of geospatially referenced information is deforestation in the tropics is currently then fed into socioeconomic and terres- known to only a very general degree. trial ecosystem models to explore the Recent research using Landsat images of causes and effects of deforestation. forest loss over a decade from the mid- Skole’s team is currently analyzing 1970s to mid-1980s found that an Landsat 5 imagery from the 1990s for the average of 6200 square miles of forest Brazilian Amazon and Southeast Asia to The cause of were lost each year in the Brazilian develop estimates of recent tropical deforestation is Amazon. The annual rate in the smaller deforestation. In addition, they are Southeast Asia region was estimated to performing multi-year studies in the being studied be 4800 square miles per year. A key Amazon basin to determine the year-to- with socio- problem facing scientists today is year changes in deforestation rates. determining deforestation rates and These data will be important not only in economic and understanding their causes and effects. yielding the rate of deforestation but for ecosystem David Skole of Michigan State the analysis of carbon uptake by tropical University is involved in several initia- rain forests and for understanding the models. tives to study the rates, causes, and social and economic causes. effects of tropical deforestation in the With the launch of Landsat 7, the Amazon Basin, Southeast Asia, and amount of data available for this re- Africa. Using Landsat imagery, his search will increase dramatically. Highly research analyzes changes in forest detailed, near-real-time analysis will be cover at a 30-m resolution and models possible with the new imagery, allowing the effects of this on the carbon cycle. By for rapid assessment of land use and combining satellite imagery with land cover change. socioeconomic data, Skole is also searching for the economic and social Contact information: David Skole, Director, causes of deforestation. Basic Science and Remote Sensing Initiative, Using three different wavelength Department of Geography, Michigan State bands of Landsat Thematic Mapper University, tel. (517) 432-7774; imagery to quantify the vegetation [email protected]. characteristics, Skole’s team categorizes Media Communications Office, Sue Nichols, land cover into primary rain forest, tel. 517-355-2281, [email protected]. regrowing rain forest, agricultural clearings, and other classes. These data are manipulated using a geographic information system to explore patterns

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Precision farming and land management

Susan Moran, U.S. Department of Agriculture

For farmers and land managers, resolution is not as good as Landsat. The increasing crop yields and cutting costs combination of radar and Landsat gives while reducing environmental pollution a continuous record of the land surface is a constant challenge. To accomplish and vegetation health. this goal, many farm managers are The thermal band on Landsat can looking for new technologies to help detect crop health by seeing plants them decide when and where to irrigate, transpire, or lose moisture through their Crop yields can fertilize, seed crops, and use herbicides. leaves—a factor directly related to plant be increased by Currently the decisions are based on health. When plant transpiration rates very limited data collected in “spot decrease, growth rates decrease and the monitoring plant checks” from the ground. plants appear unhealthy. Managers use health and plant Recent technological advances in this information to target where to geographic information systems (GIS) fertilize and irrigate. Other Landsat cover from and computer modeling are playing a bands can see the extent of vegetation space. part in farm management and precision cover while radar can pick up moisture farming. Using data collected by satel- in the soil. lites, important agricultural factors like The methods developed by Moran plant health, plant cover and soil mois- are already in use by land managers ture can be monitored from space, through a Cooperative Research and providing a much bigger picture of the Development Agreement with a com- land surface that can be combined with mercial image supplier. The 24-hour other technologies to help cut costs and turnaround of the new Landsat 7 data increase crop yields. will enable expanded applications of Susan Moran, a US Department of remote sensing in agricultural and Agriculture Agricultural Research natural resource monitoring. Service soil scientist, based in Phoenix, Ariz., developed a method to help Contact information: Susan Moran, U. S. farmers with resource management by Department of Agriculture, Agricultural combining Landsat images with radar Research Service, U. S. Water Conservation data from several polar orbiting satel- Laboratory, tel. 520-670-6380, x171; lites. Although Landsat sees the surface [email protected]. very clearly, its usefulness is limited USDA Agriculture Research Service because it can’t see through clouds, and Current Information Branch, Marcia Wood, it only flies over a particular area once 510-559-6070, [email protected]. every 16 days. Most farm management decisions require information on a daily or biweekly basis. Radar can see through clouds and be collected daily, but the

10 Science Writers’ Guide to Landsat 7

Health of temperate conifer forests

Curtis E. Woodcock, Boston University

Fire, drought, and humans all can global monitoring system for temperate destroy forests and their ecosystems. conifer forests. The monitoring system While much attention is paid to defores- will measure the rates of destruction of tation in tropical rainforests, very few conifer forests due to natural causes comprehensive studies have been done to such as drought and fire and anthropo- address changes in the Earth’s temperate genic clearing due to harvest or develop- conifer forests. Temperate conifer forests ment of forest lands. The monitoring lie at latitudes above tropical forests and system will also track the regrowth of Forest below boreal forests and account for forests and successional change in destruction much of the forested area in the United vegetation. States and Europe. The new system will work in con- from natural Understanding changes occurring in junction with NASA EOS land cover causes can be temperate conifer forests is important for change studies based on the EOS Moder- understanding environmental issues ate-resolution Imaging distinguished including wildlife habitat protection, Spectroradiometer (MODIS). The from human watershed management, timber harvest, MODIS instrument will fly aboard the and understanding the role of human Terra satellite set for launch in July 1999, activities. activities on changes in regional climates. and will be used to identify large areas Previously, researchers have only of significant changes in forest lands. been able to monitor changes in specific Following up with the finer spatial locations with Landsat data due to its resolution data from Landsat will allow limited availability. Boston University determination of the type of changes and geographer Curtis E. Woodcock and their geographic extent. colleagues used Landsat to monitor how drought in the late 1980s and early 1990s Contact information: Curtis E. Woodcock, affected forests in California’s Sierra Department of Geography and Center for Nevada. During the drought, Woodcock Remote Sensing, Boston University, tel. found that Landsat images could recog- 617-353-5746; [email protected]. nize areas where trees were dying due to Office of Public Relations, Shauna LaFauci, lack of water, a factor making the trees tel. 617-353-2399; [email protected]. more susceptible to disease and the forest more susceptible to fire. With the help of the frequent and comprehensive coverage of Landsat 7, Woodcock and colleagues plan to create a

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Gradual changes in the Antarctic ice sheet

Robert Bindschadler, NASA Goddard Space Flight Center

The stability of the West Antarctic attached to the continent but floating on Ice Sheet is an issue of active research the ocean, to determine the past 1000 and societal concern because of the years of ice flow over much of West potential economic impact resulting Antarctica. from an increase in global sea level. The Recently Landsat data have increas- West Antarctic Ice Sheet, riddled with ingly been used to create more useful deep crevasses and flowing ice streams, maps for scientific research. Ice flows may contains over 700,000 cubic miles (3 Bindschadler is combining Landsat data move more million cubic kilometers) of ice. with past surveys of the latitude, longi- Researchers are studying how the tude, and elevation of known locations quickly and ice moves and what forces cause the ice around the Antarctic continent to create slide into the to flow. If the forces change, the ice a library of image control points. The sheets may flow much more quickly and library is available on the Internet for use sea if the forces slide off the continent into the sea. by researchers. driving them Monitoring these changes from the Landsat 7 data will enhance tech- ground is difficult because treacherous niques developed at Goddard to study change. conditions allow researchers to collect ice motion and flow history by providing only a limited amount of measurements. finer spatial resolution, more continuous Robert Bindschadler, a glaciologist at spatial coverage, and an updated view of NASA’s Goddard Space Flight Center, the ever-changing Antarctic ice sheet. uses Landsat data in a variety of ways to make more information available for Contact information: Robert Bindschadler, determining the ice sheet’s behavior. NASA Goddard Space Flight Center, Landsat’s high spatial resolution allows [email protected].nasa.gov. individual crevasses to be tracked over Goddard Public Affairs Office, Lynn time. Using these natural markers not Chandler, 301-614-5562; only provides many more velocity data [email protected]. to be collected, but concentrates the measurements in the most rapidly moving and most dangerous areas. Other surface features such as flowstripes formed by rapid ice flow are also being used to uncover the history of the ice sheet. Bindschadler and col- leagues have analyzed surface features on the Ross Ice Shelf, a vast area of ice

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Mapping wildfire hazards in Yosemite

Jan van Wagtendonk, U. S. Geological Survey

In recent years, wildland fires have fuel type can be distinguished from become more intense resulting in alpine meadows which dry at a different increased loss of human life and natural rate. Similarly, biomass from deciduous Landsat resource damage. An important factor hardwood can be distinguished from in dealing with this problem is informa- evergreen hardwood, which retains its imagery is being tion on the amount and condition of dry leaves. biomass on the ground, which acts as Van Wagtendonk has also used used to identify fuel that feeds wildland fires. With single-scene Landsat images to classify different types information about fuels, fire managers different types of fuels over the past five can better predict potential fire behav- years. Maps produced from this analysis of dry biomass ior, make more informed tactical and have been used to predict the behavior on the ground. strategic decisions, and conduct treat- of two large wildland fires in 1994 and ments to reduce the amount of dry 1995 that were being allowed to burn to biomass. meet resource objectives. U. S. Geological Survey researcher The addition of a panchromatic band Jan van Wagtendonk from the Western on Landsat 7 will enhance the capability Ecological Research Center’s Yosemite to distinguish tree density classes, which National Park station, and Ralph Root, directly affects fuel moisture content and from the USGS Center for Biological wind speeds near the ground. Seasonal Informatics in Denver, have been changes can also be tracked more easily examining the use of time series of with the more frequent observations Landsat Thematic Mapper imagery for Landsat 7 will make. developing a technique to identify fuel types based on seasonal changes in plant Contact information: Jan van Wagtendonk, condition. Six Landsat scenes at one- U. S. Geological Survey, Biological month intervals during the 1992 grow- Resources Division, Western Ecological ing season are being examined using Research Center, Yosemite Field Station, hyperspectral analysis, a type of analysis El Portal, Calif.; tel. 209-379-1885, that deals with large data sets with [email protected]. several spectral bands. Sonoran Desert Field Station, University of Using the time series, changes in Arizona, Gloria Meander, tel. 520-670-6896 annual grasslands, for instance, can be x1, [email protected]. traced as the plants green up in the spring and dry during the summer. This

13 Science Writers’ Guide to Landsat 7

Glossary

Band (channel). A band is a slice of Panchromatic. Sensitive to all or most of wavelengths from the electromagnetic the visible spectrum, between 0.4 and 0.7 spectrum. Landsat ETM+ has eight micrometers. Landsat 7 has a panchro- bands which collect radiation from matic band. different parts of the electromagnetic spectrum. Of the eight bands, three Passive sensor. One type of remote bands are visible light, one band is sensing instrument, a passive sensor panchromatic, three bands are infrared, picks up radiation reflected or emitted and one band is thermal infrared. by the Earth. ETM+ is a passive remote sensing system. Enhanced Thematic Mapper Plus (ETM+). The sensor aboard Landsat 7 Polar orbit. An orbit with its plane that picks up solar radiation reflected by, aligned parallel with the polar axis of or emitted from the Earth. the Earth. Landsat’s polar orbit is 438 miles (705 kilometers) above the Earth. Electromagnetic radiation. Energy transfer in the form of electromagnetic Radar. Short for “radio detection and waves or particles that propagate ranging,” radar sends out short pulses of through space at the speed of light. microwave energy and records the returned signal’s strength and time of Electromagnetic spectrum. The entire arrival. range of electromagnetic radiation. The spectrum usually is divided into seven Resolution. A measure of the amount of sections. From the longest wavelengths detail that can be seen in an image. to the shortest: radio, microwave, infrared, visible, ultraviolet, x-ray, and Scenes. Each Landsat image collected is gamma-ray radiation. called a scene. Each scene is 115 x 106 miles long. The globe is divided into Geostationary orbit. An orbit in which a 57,784 scenes. satellite is always in the same position with respect to the rotating Earth. The Synoptic view. The ability to see large satellite travels around the Earth in the areas at one time, such as an entire same direction, at an altitude of approxi- metropolitan area. mately 22,000 miles (35,800 kilometers). Thermal infrared. Electromagnetic Infrared radiation. Electromagnetic radiation with wavelengths between 3 radiation with wavelengths between and 25 micrometers. about 0.7 to 1000 micrometers. Infrared waves are not visible to the human eye. Visible radiation. The electromagnetic Longer infrared waves are called ther- radiation that humans can see as colors. mal infrared waves. The visible spectrum is made up of wavelengths between 0.4 to 0.7 mi- Multispectral image. A remote sensing crometers. Red is the longest and violet image created using data collected from is the shortest. Landsat 7 has three more than one band. visible bands in red, green, and blue. 14 Science Writers’ Guide to Landsat 7

Contact Information

Landsat 7 Science Team Robert Cahalan Code 913 Darrel Williams NASA Goddard Space Flight Center Landsat 7 Project Scientist Greenbelt, MD 20771 Code 923 301-286-4276 NASA Goddard Space Flight Center [email protected] Greenbelt, MD 20771 301-286-8860 Luke Flynn [email protected] University of Hawaii Hawaii Institute of Geophysics & James Irons Paleontology Deputy Landsat 7 Project Scientst 2525 Correa Rd. Code 923 Honolulu, HI 96822 NASA Goddard Space Flight Center 808-956-3154 Greenbelt, MD 20771 [email protected] 301-286-8978 [email protected] Alexander Goetz University of Colorado Samuel Goward Boulder CSES Landsat 7 Science Team Leader Campus Box 216 University of Maryland Boulder , CO 80309 Department of Geography 303-492-5086 College Park , MD 20742 [email protected] 301-405-4050 [email protected] Susan Moran U.S. Department of Agriculture Jeffrey Masek Water Conservation Lab Landsat 7 Deputy Team Leader 2000 E. Allen Rd. University of Maryland Tucson, AZ 85719 Department of Geography 520-670-6380 College Park, MD 20742 [email protected] 301-405-8233 [email protected] Frank Muller-Karger University of South Florida Robert Bindschadler Dept. of Marine Science Code 971 140 7th Avenue South NASA Goddard Space Flight Center St. Petersburg, FL 33701 Greenbelt, MD 20771 813-893-9186 301-286-7611 [email protected] [email protected]

15 Science Writers’ Guide to Landsat 7

Frank Palluconi Curtis Woodcock Jet Propulsion Laboratory Boston University M/S 183-501 Dept. of Geography 4800 Oak Grove Dr. 675 Commonwealth Ave. Pasadena CA 91109 Boston MA 02215 818-354-8362 617-353-5746 [email protected] [email protected]

John Price Program Management 765 10th Street Boulder, CO 80302 Phillip A. Sabelhaus 303-939-9991 Landsat 7 Project Manager [email protected] NASA Goddard Space Flight Center Greenbelt, MD 20771 John Schott 301-286-8536 Rochester Institute of Technology [email protected] Center for Imaging Science 54 Lomb Memorial Dr. Ray Byrnes Rochester NY 14623 USGS Land Satellite Program Liaison 716-475-5170 508 National Center [email protected] Reston, VA 20192 703-648-4787 David Skole [email protected] Michigan State University 315 Natural Science R. J. Thompson East Lansing MI 48824 USGS Landsat Program Manager 517-355-4649 USGS EROS Data Center [email protected] Sioux Falls, SD 57198 605-594-6161 Kurtis Thome [email protected] University of Arizona Meinel Building Public Affairs P.O. Box 210094 Tucson AZ 85721 David Steitz 520-621-4535 Public Affairs Office kurt@titan.opt-sci.arizona.edu Rm 5N22 NASA Headquarters James Vogelman Washington, DC 20546 Hughes STX Corporation 202-358-1730 U.S. Geological Survey EROS Data [email protected] Center Sioux Falls, SD 57198 Lynn Chandler 605-594-6062 Public Affairs Office [email protected] Code 130 NASA Goddard Space Flight Center Greenbelt, MD 20771 301- 614-5562 [email protected] 16 Science Writers’ Guide to Landsat 7

Allen Kenitzer Web Sites Public Affairs Office Code 130 The Landsat 7 Program NASA Goddard Space Flight Center http://geo.arc.nasa.gov/sge/landsat/ Greenbelt, MD 20771 landsat.html 301-286-2806 Information on Landsat satellite data, [email protected] program news, program history and chronology, and instrument details. Wade Sisler Executive TV Producer Landsat 7 Gateway NASA Goddard Space Flight Center http://landsat.gsfc.nasa.gov/ Greenbelt, MD 20771 Program and technical information, 301-286-6256 educational materials, an image gallery, [email protected] and NASA organizational information.

Ron Beck Landsat 7 Science Team USGS EROS Data Center http://www.inform.umd.edu/geog/ Sioux Falls, SD 57198 landsat7/ 605-594-6551 The “Public information about Landsat 7 [email protected] Science Activities” section contains instrument details, how images are Cathy Watson acquired, and contact information for USGS Office of Outreach science team members. 119 National Center Reston, VA 20192 Landsat 7 Images 703-648-4732 [email protected] Individual stills of new Landsat 7 images can be obtained by contacting Ron Beck, USGS EROS Data Center, Sioux Falls, SD 57198; tel. 605-594-6551; [email protected].

A “pre-launch resource videotape” of Landsat scenes and animations is available for media use from the Goddard Space Flight Center’s Public Affairs Office. Contact Deanna Corridon for more information; tel. 301-286-0041.

17 Earth Observing System Project Science Office Code 900 NASA Goddard Space Flight Center Greenbelt, MD 20771

NASA’s Earth Science Enterprise Code Y NASA Headquarters Washington, DC 20546

U.S. Geological Survey EROS Data Cemter Sioux Falls, SD 57198 NP-1999-02-022-GSFC