These Landsat 7 Collection 1 Tier 1 composites are made from Tier 1 orthorectified scenes, using the
computed top-of-atmosphere (TOA) reflectance.
See Chander et al. (2009)
for details on the TOA computation.
The Normalized Difference Snow Index is used to
identify snow, based on its characteristically higher reflectance in
the visible portion of the spectrum compared to the mid-IR. NDSI is
computed using the Green and Mid-IR bands, and has a range of -1.0 to
1.0. See
Riggs et al. (1994) for details.
These composites are created from
all the scenes in
each annual period beginning from the first day of the year and
continuing to the last day of the year. All the images from each year
are included in the composite, with the most recent pixel as the composite value.
Bands
Bands
Name
Pixel Size
Description
NDSI
30 meters
Normalized Difference Snow Index
Terms of Use
Terms of Use
Landsat datasets are federally created data
and therefore reside in the public domain and may be used, transferred, or reproduced without copyright restriction.
Acknowledgement or credit of the USGS as data source should be provided
by including a line of text citation such as the example shown below.
(Product, Image, Photograph, or Dataset Name) courtesy of
the U.S. Geological Survey
Example: Landsat-7 image courtesy of the U.S. Geological Survey
These Landsat 7 Collection 1 Tier 1 composites are made from Tier 1 orthorectified scenes, using the computed top-of-atmosphere (TOA) reflectance. See Chander et al. (2009) for details on the TOA computation. The Normalized Difference Snow Index is used to identify snow, based on its characteristically higher reflectance in the …
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],[],[[["The dataset provides annual Landsat 7 Collection 1 Tier 1 composites, created from orthorectified scenes with top-of-atmosphere (TOA) reflectance."],["It utilizes the Normalized Difference Snow Index (NDSI) to identify snow cover, calculated using Green and Mid-IR bands."],["The dataset covers the period from 1999 to 2021, with each annual composite including all scenes from the respective year."],["Images are available at a 30-meter pixel resolution and are provided by the U.S. Geological Survey (USGS), residing in the public domain."],["The dataset is accessible through Google Earth Engine and is free to use for research, education, and non-profit purposes."]]],["The Landsat 7 Collection 1 Tier 1 annual composites, available from 1999 to 2021 via Google Earth Engine, utilize the Normalized Difference Snow Index (NDSI) to identify snow, computed with Green and Mid-IR bands. These composites, derived from orthorectified scenes, incorporate top-of-atmosphere (TOA) reflectance. Data users must cite the USGS as the data source and have free access for research, education, and non-profit applications, following the USGS Visual Identity System Guidance. The data is accessble using `ee.ImageCollection(\"LANDSAT/LE07/C01/T1_ANNUAL_NDSI\")`.\n"]]
