Description
A data block that provides MODIS true-color images at processing level 2. These images are acquired by the Terra satellite sensor at a revisit rate of 1-2 days anywhere on the globe. Terra's orbit around the Earth is timed so that it passes from north to south across the equator in the morning. The datasets are available starting with 2000.
See this block on the marketplace.
Technical information
Compatible blocks
- K-means Clustering
- Raster CRS Conversion
Geographic coverage
The geographic coverage is global.
Dataset information
| Specifications | Description |
|---|---|
| Data provider | NASA Global Imagery Browse Services |
| Spatial resolution (m) | 250 |
| Image type | Optical |
| Spectral bands | Red - Band 1 Green - Band 4 Blue - Band 3 |
| Acquisition mode | Mono |
| Geometric processing level | Ortho |
| Radiometric processing level | L2 (Corrected reflectance) |
| Revisit frequency | Daily |
| Data availability | Since 2000 |
| File format | GeoTIFF |
| Bit depth per pixel | 8-bit 16-bit |
| Coordinate system | WGS84/Pseudo-Mercator (EPSG:3857) |
| Can be reused in an UP42 workflow | No |
Limitations
Data cannot be queried based on scene ID.
This data block also provides MODIS-derived data such as the Normalized Difference Vegetation Index (NDVI) (rolling 8-day average) product or the Corrected Reflectance for Bands 7-2-1.
Available Layers
The default layer is MODIS_Terra_CorrectedReflectance_TrueColor. The full list of available layers can be found in the modis repository. These layers originate from the GIBS Available Imagery Products and they have the same extent and resolution as the MODIS true-color layer.
The generated GeoTIFF image file includes all the layers defined in the job parameters. These layers are added as individual bands in the order specified in the job parameters. Tags are also written into the output file with the origin of each band (see example metadata for a raster rendered in QGIS).
| Layer identifier | Description |
|---|---|
MODIS_Aqua_CorrectedReflectance_TrueColor | Aqua is the second MODIS satellite with an afternoon crossing time. |
MODIS_Terra_NDVI_8Day | A rolling 8-day NDVI average computed with MODIS Terra imagery. |
MODIS_Terra_EVI_8Day | A rolling 8-day EVI average computed with MODIS Terra imagery. |
MODIS_Terra_CorrectedReflectance_Bands367 | Bands 3,6 and 7 are useful for determining Land/Cloud/Aerosols properties. |
MODIS_Terra_CorrectedReflectance_Bands721 | Bands 7,2 and 1 are useful for determining Land/Cloud/Aerosols boundaries. |
When rendering a 4-band raster with uint8 as data type into a GIS software like QGIS, band 4 is set as the alpha band (transparency band) by default. You can turn the alpha band off by going to Layer Properties and setting the transparency band to None in the tab Transparency.
How it works
| Supported JSON parameters | Default value | Min | Max | Examples |
|---|---|---|---|---|
time | "2018-01-01T00:00:00+00:00/2021-12-31T23:59:59+00:00" | 01.01.2000 | present | "time": "2016-11-01T00:00:00+00:00/2016-11-30T23:59:59+00:00" |
limit | 1 | 1 | n.a. | "limit": 80 |
zoom_level | 9 | 9 | 9 | "zoom_level": 9 |
imagery_layers | "MODIS_Terra_CorrectedReflectance_TrueColor" | n.a. | n.a. | "imagery_layers": ["MODIS_Terra_NDVI_8Day"] |
bbox/contains/intersects | null | n.a. | n.a. | Please check the examples from the JSON parameters. |
Examples
Example based on a workflow created with the data block MODIS (GeoTIFF):