Landsat 7 ETM+ L2

About Landsat 7 ETM+ Collection 2 Level 2 Data

Mission Information

The Landsat 7 Enhanced Thematic Mapper (ETM+) sensor is carried onboard Landsat 7. It provides 7 spectral bands and 1 thermal band. Learn more about here.

Basic Facts

PropertyInfo
Spatial resolution30 m (the thermal band is re-sampled from 60 m)
SensorEnhanced Thematic Mapper (ETM+) with 7 spectral bands and 1 thermal band
Revisit time16 days
Spatial coverageWhole globe
Data availabilitySince April 1999

Accessing Data

To access data you need to send a POST request to our process API. The requested data will be returned as the response to your request. Each POST request can be tailored to get you exactly the data you require. To do this requires setting various parameters which depend on the collection you are querying. This chapter will help you understand the parameters for Landsat 7 ETM+ Level 2 data. For an overview of all API parameters see the API Reference.

Endpoint Locations

ServiceNotes
services-uswest2.sentinel-hub.com/apiGlobal coverage since April 1999.

Data type identifier: landsat-etm-l2

Use landsat-etm-l2 [1] (previously LETML2) as the value of the input.data.type parameter in your API requests. This is mandatory and will ensure you get Landsat 7 ETM+ Level 2 data.

The collection is currently in the preview stage and might thus change.

[1]: landsat-etm-l2 stands for Landsat Enhanced Thematic Mapper Level 2.

Filtering Options

This chapter will explain the input.data.dataFilter object of the process API.

mosaickingOrder

Sets the order of overlapping tiles from which the output result is mosaicked. Note that tiles will in most cases come from the same orbit/acquisition. The tiling is done by USGS for easier distribution.

ValueDescriptionNotes
mostRecentselected by default. The pixel will be selected from the tile, which was acquired most recentl
leastRecentsimilar to mostRecent but in reverse order
leastCCpixel is selected from tile with the least cloud coverage metadatanote that "per tile" information is used here, each covering about a 31,000 sq. km area, so this information is only an estimate.

maxCloudCoverage

Sets the upper limit for cloud coverage in percent based on the precomputed cloud coverage estimate for each tile as present in the tile metadata. Satellite data will therefore not be retrieved for tiles with a higher cloud coverage estimate. For example, by setting the value to 20, only tiles with at most 20% cloud coverage will be used. Note that this parameter is set per tile and might not be directly applicable to the chosen area of interest.

tiers

Selects product tiers.

ValueDescription
TIER_1selects Tier 1 products
ALL_TIERSselected by default. selects Tier 1 and Tier 2 products

Processing Options

This chapter will explain the input.data.processing object of the process API.

ActionDescription
upsamplingThe same as for S2L1C.
downsamplingThe same as for S2L1C.

Available Bands and Data

Information in this chapter is useful when defining input object in evalscript. Any string listed in the column Name can be an element of the input.bands array in your evalscript.

NameDescriptionResolution
B01Blue (450-520 nm)30m
B02Green (520-600 nm)30m
B03Red (630-690 nm)30m
B04Near Infrared (NIR) (770-900 nm)30m
B05Shortwave Infrared (SWIR) 1 (1550-1750 nm)30m
B06Thermal Infrared (10400-12500 nm)30m [1]
B07Shortwave Infrared (SWIR) 2 (2090-2350 nm)30m
BQAQuality Assessment band (QA)30m
QA_RADSATRadiometric Saturation and Terrain Occlusion Quality Assessment Band30m
ST_QASurface Temperature Uncertainty30m
ST_TRADLevel-1 thermal band converted to thermal surface radiance30m
ST_URADUpwelled Radiance30m
ST_DRADDownwelled Radiance30m
ST_ATRANAtmospheric Transmittance30m
ST_EMISEmissivity estimated from ASTER GED30m
ST_EMSDEmissivity standard deviation30m
ST_CDISTPixel distance to cloud30m
SR_ATMOS_OPACITYInternal SR Atmospheric Opacity30m
SR_CLOUD_QACloud Quality Assessment30m
dataMaskThe mask of data/no data pixels (more).N/A [1]

[1]: Thermal band is acquired at 60 meter resolution, but is resampled to 30 meter in delivered data product (source).
[2]: dataMask has no source resolution as it is calculated for each output pixel.

Units

The data values for each band in your custom script are presented in the units as specified here. In case more than one unit is available for a given band, you may optionally set the value of input.units in your evalscript setup function to one of the values in the Sentinel Hub Units column. Doing so will present data in that unit. The Sentinel Hub units parameter combines the physical quantity and corresponding units of measurement values. As such, some names more closely resemble physical quantities, others resemble units of measurement.

The Source Format specifies how and with what precision the digital numbers (DN) from which the unit is derived are encoded. Bands requested in DN units contain exactly the pixel values of the source data. Note that resampling may produce interpolated values. DN is also used whenever a band is derived computationally (like dataMask); such bands can be identified by having DN units and N/A source format. DN values are typically not offered if they do not simply represent any physical quantity, in particular, when DN values require source-specific (i.e. non-global) conversion to physical quantities.

Values in non-DN units are computed from the source (DN) values with at least float32 precision. Note that the conversion might be nonlinear, therefore the full value range and quantization step size of such a band can be hard to predict. Band values in evalscripts always behave as floating point numbers, regardless of the actual precision.

The Typical Range indicates what values are common for a given band and unit, however outliers can be expected.

BandPhysical Quantity (units)Sentinel Hub UnitsSource FormatTypical RangeNotes
Optical bands
B01 - B05, B07
Surface reflectance (unitless)REFLECTANCEUINT160 - 0.4Higher values in infrared bands. Reflectance values can easily be above 1.
Thermal infrared band
B06
Surface temperature (Kelvin)SURFACE_TEMPERATUREUINT16250 - 320Surface temperature of roughly -20 to +50 C. Can reach outside this range in extreme environments.
BQAPixel quality assessment (unitless)DNUINT16bit-packed combination [1]
QA_RADSATRadiometric saturation quality assessment (unitless)DNUINT16bit-packed combination [1]
ST_QASurface temperature uncertainty (Kelvin)KELVININT16
ST_TRADRadiance (W / (m2 sr μm))RADIANCEINT16
ST_URADRadiance (W / (m2 sr μm))RADIANCEINT16
ST_DRADRadiance (W / (m2 sr μm))RADIANCEINT16
ST_ATRANAtmospheric transmittance (unitless)FRACTIONINT160 - 1
ST_EMISEmissivity (unitless)FRACTIONINT160 - 1
ST_EMSDEmissivity standard deviation (unitless)FRACTIONINT160 - 1
ST_CDISTPixel distance (kilometers)KILOMETERSINT16
SR_ATMOS_OPACITYOpacity (unitless)FRACTIONINT160 - 1
SR_CLOUD_QACloud mask quality (unitless)DNUINT8bit-packed combination (info here)
dataMaskN/ADNN/A0 - no data
1 - data

[1]: Info here.

Catalog API Capabilities

To access Landsat product metadata you need to send search request to our Catalog API. The requested metadata will be returned as JSON formatted response to your request.

Endpoint Locations

ServiceNotes
services-uswest2.sentinel-hub.com/api/v1/catalog/collections/landsat-etm-l2Data availability and coverage is the same as in the basic facts

Collection identifier: landsat-etm-l2

Query extension

  • eo:cloud_cover cloud cover percentage

Distinct extension

  • date