Landsat satellites provide high-quality, multi-spectral imagery of the surface of the Earth. These moderate-resolution, remotely sensed images are not just pictures, but contain many layers of data collected at different points along the visible and invisible light spectrum. These data can be manipulated to reveal what the Earth’s surface looks like, including what types of vegetation are present or how a natural disaster has impacted an area (Fig. 1).
Currently, there are two Landsat satellites producing imagery: Landsat 5 and Landsat 7. The next satellite, Landsat Data Continuity Mission (LDCM), is scheduled to launch at the end of 2012. While many other satellites provide imagery, Landsat images are unique in three ways:
No other satellite imagery has that combination of attributes, which makes Landsat imagery of particular value to the global community. Understanding the value of the imagery provided by Landsat satellites is essential as future land-imaging initiatives move forward.
In a project initiated by the U.S. Geological Survey’s Land Remote Sensing Program and in conjunction with researchers at the USGS Western Geographic Science Center, the USGS Fort Collins Science Center’s Policy Analysis and Science Assistance Branch (PASA) is conducting a national multi-stage study to investigate the users, uses, and benefits of Landsat imagery. The goals of this study are to (1) identify and classify Landsat imagery users, (2) better understand the specific uses of the imagery as well as the extent to which it is used, and (3) determine the value of Landsat imagery to the users. The study is being implemented in three stages:
PASA scientists completed the first stage of the study, a Web-based survey of nearly 2,500 satellite imagery users, in 2010. The results provided a comprehensive assessment of users and uses of Landsat imagery, along with users of other types of satellite imagery. Survey recipients were selected using a unique combination of a Web search followed by snowball sampling (a technique that finds additional users of Landsat imagery by asking confirmed users to identify people they personally know who also use the imagery) to identify a cross-section of professional users in private, academic, government (Federal, State, and local), and nonprofit sectors. The sample consisted of a broad range of users from each of these sectors, who use the imagery in more than 35 different application areas for local to global-scale projects all over the world. The survey investigated (1) these various uses of moderate-resolution imagery, (2) the potential impacts on users and their work if Landsat imagery were unavailable, and (3) users’ willingness to pay for replacement imagery, which we assessed using the contingent valuation method. View the executive report or view additional data not included in the report.
The second stage of the study, set to begin in 2011, will consist of a survey of Landsat users who have procured imagery from the USGS Earth Resources Observation and Science Center (EROS). EROS is responsible for operating the Landsat satellites, as well as downloading, processing, archiving, and distributing all imagery from those satellites. From 2007 through 2010, almost 42,000 different users around the world procured imagery from EROS, providing a much larger, though potentially less diverse, pool of users to sample than the first survey. The goals of the survey are to (1) identify new users who began using the imagery only after it became free at the end of 2008, (2) examine how new users apply and value the imagery compared to established users, and (3) discover more about international users of Landsat imagery.
The third stage will explore the value of Landsat imagery through case studies. The case studies will provide an opportunity to extensively research individual applications of Landsat imagery, including an in-depth look at the market and non-market value of the imagery within a given application. Each case study will focus on one application of the imagery in one area of the globe. The first case study, scheduled for 2011, will examine the value of using Landsat imagery to address water issues in the western United States. Landsat imagery can be used to measure water use in agriculture, examine water quality, and explore broader ecosystem issues that impact water quality and quantity (Fig. 3). Other case studies will be determined at a future date.