Curtis E. Woodcock,Richard G. Allen,Martha C. Anderson,Alan Belward,Robert Bindschadler,Warren B. Cohen,Feng Gao,Samuel N. Goward,Dennis L. Helder,Eileen H. Helmer,R. R. Nemani,Lazaros Oreopoulos,J. R. Schott,Prasad S. Thenkabail,Éric Vermote,James E. Vogelmann,Michael A. Wulder,Randolph H. Wynne
出处
期刊:Science [American Association for the Advancement of Science (AAAS)] 日期:2008-05-23卷期号:320 (5879): 1011-1011被引量:737
![Figure][1]
Free image.
This Landsat 5 image of the southeastern corner of the Black Sea is part of the general U.S. archive that will be accessible for free under the new USGS policy.
CREDIT: BOSTON UNIVERSITY CENTER FOR REMOTE SENSING
We are entering a new era in the Landsat Program, the oldest and most venerable of our Earth-observing satellite programs. With little fanfare, the U.S. Geological Survey (USGS) has begun providing imagery for free over the Internet. Throughout the history of the Landsat Program, the cost and access to imagery has always limited our ability to study our planet and the way it is changing. Beginning with a pilot program to provide “Web-enabled” access to Landsat 7 images of the United States that were collected between 2003 and this year, the USGS now plans to provide top-quality image products for free upon request for the entire U.S. archive, including over 2 million images back to Landsat 1 (1972) [for details and schedules, see ([1][2])]. The release by NASA and the USGS in January 2008 of a new Landsat Data Distribution Policy ([2][3]) was a key step to this goal. Free imagery will enable reconstruction of the history of Earth's surface back to 1972, chronicling both anthropogenic and natural changes during a time when our population doubled and the impacts of climate change became noticeable.
The Landsat Science Team:
1. 1.[↵][4]USGS Technical Announcement ([http://landsat.usgs.gov/images/squares/USGS\_Landsat\_Imagery_Release.pdf][5]).
2. 2.[↵][6]Landsat Missions ([http://ldcm.usgs.gov/pdf/Landsat\_Data\_Policy.pdf][7]).
[1]: pending:yes
[2]: #ref-1
[3]: #ref-2
[4]: #xref-ref-1-1 View reference 1. in text
[5]: http://landsat.usgs.gov/images/squares/USGS_Landsat_Imagery_Release.pdf
[6]: #xref-ref-2-1 View reference 2. in text
[7]: http://ldcm.usgs.gov/pdf/Landsat_Data_Policy.pdf