MODIS Land Products explained

Author: Matt Paget, CSIRO Land and Water (2020)

The TERN AusCover facility (2010-2018) distributed Australian mosaic data products for a set of MODIS Land Products. The mosaic products have all been retired and are no longer available from TERN. This page explains why and offers alternative paths for users to access these data.

Metadata records for the mosaic products have been updated into the TERN Geonetwork service but the data are no longer available.

The short explanation

The mosaics were created from original sinusoidal-projection tiles (files) distributed by USGS, see https://lpdaac.usgs.gov/.

In 2017 and 2018, USGS and the product science teams transitioned MODIS LPDAAC products from Collection 5 to Collection 6, see https://lpdaac.usgs.gov/news/decommissioning-of-modis-version-5-land-data-products-on-april-9-2018-second-notice/.

The majority of the changes were for product algorithm improvements but there were also file format and structure changes for some products. These format and structure changes would have required an update to the CSIRO mosaicing code, which CSIRO (nor TERN) were not in a position to do at the time.

Also at the time, CSIRO and Geoscience Australia with the NCI were developing the Australian Geoscience Data Cube (AGDC, later the Open Data Cube), and this was seen as a better path forward as it would allow on-demand mosaicing, reprojection and subsetting.

The AusCover MODIS mosaic land products

The AusCover MODIS mosaic land products were produced by CSIRO. The method and rationale are presented in Paget & King (2008). The mosaics were created from sinusoidal-projection tiles (files) distributed by USGS. The workflow included:

1. Regularly download the 17 tiles that cover Australia.

2. Use the MODIS Reprojection Tool to mosaic the 17 tiles and then reproject the mosaic to WGS84.

3. Re-write the mosaics into consistent and standard HDF4 and netCDF4 formats.

4. Make publicly available via CSIRO, NCI and TERN.

The reprojection to WGS84 was deemed appropriate when the first version was released in 2007. However, by 2018 and consistent with the design and discussions within the AGDC, it was deemed more appropriate to store the data in its native tiled format and allow the software to do on-demand mosaicing, reprojection and subsetting.

CSIRO and TERN acknowledge that the MODIS mosaic products were well used and popular due to their ease of access and use.

See below for the list of AusCover MODIS mosaic land products that were produced.

How to get the MODIS land products data now

USGS / LPDAAC

The latest MODIS land products data can be freely downloaded from USGS. Users require an EarthExplorer login (free) to access many USGS and NASA satellite data resources. For download and access options, see https://lpdaac.usgs.gov/tools/.

• Data pool > direct file download over HTTP

• OPeNDAP > file subsetting into an OPeNDAP client and download over HTTP

• AppEEARS > API for subsetting and download result as netCDF

Files in the Data pool and OPeNDAP are in sinusoidal projection: https://modis-land.gsfc.nasa.gov/MODLAND_grid.html. GDAL and similar tools will read the data. The AppEEARS API can reproject and reformat the data on request.

Google Earth Engine

A number of the MODIS land products are available for use directly in GEE.

CSIRO and NCI

CSIRO continues to download and mirror the sinusoidal tiles (via the data pool) for selected products for its own projects. Some of these data are synced to the NCI for projects on the NCI. CSIRO is scaling-back their download and archive mirroring for these data to focus only on current CSIRO projects. Aside from use in projects, CSIRO does not do any value-add to the downloaded data.

CSIRO public access: TBC (no reason not to aside from priorities)

NCI access: https://dapds00.nci.org.au/thredds/catalog/u39/public/data/modis/lpdaac-tiles-c6/catalog.html (not all products are mirrored and up to date but requests to update will be considered)

Digital Earth Australia

Digital Earth Australia (DEA) is Geoscience Australia’s platform for the Open Data Cube. At the time of writing, DEA does not support access to the MODIS land products, although the capability exists.

CSIRO Earth Analytics Science and Innovation (EASI) platform

EASI is CSIRO’s platform for the Open Data Cube. It differs from DEA in that it includes CSIRO IP components as well as public-good components. EASI will support access to MODIS land products.

List of AusCover MODIS mosaic land products

Quick links

The LPDAAC product references link to the respective Collection 6 products. On each product page see the “Improvements/Changes from Previous Versions” section to review the changes between Collection 5 and 6.

Open

Surface reflectance (MxD09, collection 5)

The MODIS Surface Reflectance products (short names: MOD09A1, MOD09Q1, MOD09GA, MYD09A1, MYD09Q1, MYD09GA) provide an estimate of the surface spectral reflectance of Terra and Aqua MODIS Bands 1 through 7 corrected for atmospheric conditions such as gasses, aerosols, and Rayleigh scattering (Vermote, 2015).

Open

Land Surface Temperature and Emissivity (MxD11Ax, collection 5)

The MODIS Land Surface Temperature and Emissivity product (short names: MOD11A1, MYD11A1, MOD11A2, collection 5) provides daily surface temperature values for both day and night conditions. The surface emissivity is estimated using land cover type (Wan et al, 2015).

Land Cover Type (MCD12Q1, collection 5.1)

The MODIS Land Cover Type product (short name: MCD12Q1) provides land cover types at yearly intervals (2001-2018) derived from five different classification schemes: IGBP, UMD, LAI, BGC, and PFT (Friedl and Sulla-Menashe, 2019).

Land Cover Dynamics (MCD12Q2, collection 5)

The MODIS Land Cover Dynamics product (short name: MCD12Q2) provides global land surface phenology metrics at yearly intervals from 2001 to 2017. Vegetation phenology metrics are identified for up to two detected growing cycles per year (Friedl et al, 2019).

Vegetation Indices (MOD13Q1, collection 5)

The MODIS Vegetation Indices product (short name: MOD13Q1) provides the Normalized Difference Vegetation Index (NDVI) and the Enhanced Vegetation Index (EVI), which has improved sensitivity over high biomass regions (Didan, 2015).

Thermal Anomalies (Fire Hotspots) (MOD14A2, collection 5)

The MODIS Thermal Anomalies and Fire product (short name: MOD14A2) identifies thermal hotspots or anomolies and classifies these according to a set of rules. The product is a composite of the maximum value of the individual fire pixel classes (Giglio et al, 2015).

Leaf Area Index and FPAR (MOD15A2, collection 5)

The MODIS Leaf Area Index (LAI) / FPAR product (short name: MOD15A2) provides information on the photosynthetic properties of vegetation canopies. LAI is the green leaf area per unit ground area. The Fraction of Photosynthetically Active Radiation (FPAR) is the fraction of incident radiation in the range 400-700 nanometers (nm) that is absorbed by the green elements of a vegetation canopy (Myneni et al, 2015).

Gross Primary Productivity (MOD17A2, collection 5)

The MODIS Gross Primary Productivity (GPP) product (short name: MOD17A2) is a cumulative composite of GPP values based on the radiation use efficiency concept that can be potentially used as inputs to data models to calculate terrestrial energy, carbon, water cycle processes, and biogeochemistry of vegetation (Running et al, 2015).

BRDF, Albedo and Nadir BRDF-Adjusted Reflectance (MCD43, collection 5)

The MODIS BRDF, Albedo and Nadir BRDF-Adjusted Reflectance products (short names: MCD43A1, MCD43A2, MCD43A3, MCD43A4, collection 5) provide bidirectional reflectance distribution function (BRDF) and Albedo model parameters, and nadir BRDF-adjusted reflectance (NBAR) data across four products (Schaaf et al, 2015).

Vegetation Continuous Fields (MOD44B, collection 3)

The MODIS Vegetation Continuous Fields product (short name: MOD44B) is a global representation of surface vegetation cover as gradations of three ground cover components: percent tree cover, percent non-tree cover, and percent non-vegetated (bare) (Dimiceli et al, 2015).

Burned Area (MCD45A1, collection 5.1)

The MODIS Burned Area product (short name: MCD45A1) identifies rapid changes in the daily surface reflectance, and uses that information to approximate the date of burning and map the spatial extent of recent fires (Giglio et al, 2015).

Active-fire based Burned Area (MCD64A1, collection 5)

The MODIS Active-fire based Burned Area product (short name: MCD64A1) combines active-fire and reflectance data to adapt regionally over a wide range of pre- and post-burn conditions and across multiple ecosystems. This product superseeds MCD45A1. The TERN AusCover mosaic product used the collection 5 version distributed by the University of Maryland (http://dx.doi.org/10.1016/j.rse.2008.10.006).