Published on February 21, 2014
MODIS Land and HDF-EOS MODIS Land and HDF-EOS HDF-EOS Workshop Presentation September 20, 2000 Robert Wolfe NASA GSFC Code 922, Raytheon ITSS MODIS Land Science Team Support
MODIS Land Science Team Products MODIS Land Science Team Products • Goals : – operationally produce terrestrial remotely sensed products that may be used by expert and non-expert community – establish a 10 year record that has continuity with precursor systems, e.g., AVHRR, and the future NPP and NPOESS VIIRS missions • The MODIS products were developed primarily to serve the global change research community (MODIS has global, near daily coverage) and have many other potential applications • The MODIS Land Science team was completively selected to develop peer-reviewed product generation algorithms (10 Principal Investigators, lead: Chris Justice, UVA) HDF-EOS 2
MODIS Land Product Overview (1/3) MODIS Land Product Overview (1/3) • Radiation Budget Variables – Surface Reflectance – Surface Temperature and Emissivity – Snow and Ice Cover – BRDF and Albedo HDF-EOS 3
MODIS Land Product Overview (2/3) MODIS Land Product Overview (2/3) • Ecosystem Variables – Vegetation Indices – Leaf Area Index (LAI) and Fractional Photosynthetically Active Radiation (FPAR) – Vegetation Production – Net Primary Productivity (NPP) HDF-EOS 4
MODIS Land Product Overview (3/3) MODIS Land Product Overview (3/3) • Land Cover Characteristics • Fire and Thermal Anomalies • Land Cover • Vegetation Cover Conversion HDF-EOS 5
MODIS Production and Distribution MODIS Production and Distribution Level 0 Instrument Data Level 1, Ocean and Atmos. Products GSFC DAAC • User Community MODIS Land production commenced 02/26/2000 • Product checkout is underway, driven by instrument calibration, geolocation, algorithm code stability and data dependencies • Land products Beta release from the DAACs began 08/04/2000 • Current products are for evaluation purposes Ocean and Atmosphere Products Level 1 Products MODAPS Land Snow and Ice Cover Products Land Non-cryospheric Products NSIDC DAAC EDC DAAC User Community HDF-EOS 6
MODLAND Grids MODLAND Grids • • Fine resolution grids for the L2G, 3 and 4 products are based on two map projections: – Integerized Sinusoidal Grid (ISIN) – Lambert Azimuthal Equal-Area (LAEA) (polar grids) – Almost all of the fine resolution products will be made in the ISIN • Exception: Sea-ice products are made in the in the LAEA projection with the grid centered at the north and south poles (EASI Grid implementation) – Grid cell size varies by product and is either (approx.) 0.25 km, 0.5 km or 1 km – actual size depends on the projection – Each grid is broken into non-overlapping tiles which cover approx. 10 x 10 deg. area Coarse resolution global Climate Modeling Grid (CMG) products are made in a geographic projection with grid cell sizes of 0.25 or 0.5 deg. HDF-EOS 7
ISIN Grid ISIN Grid HDF-EOS 8
HDF-EOS Usage (1/2) HDF-EOS Usage (1/2) • Both swath and grid format Type Interim Archive L2 Swath 1 5 ISIN 8 30 LAEA (Polar) 3 2 CMG (Geog.) 0 19 Total 12 56 Total 6 38 5 19 68 • 2d, 3d and some 4d SDS arrays • Global and SDS attributes HDF-EOS 9
HDF-EOS Usage (2/2) HDF-EOS Usage (2/2) • Subsetting/mosaicing – Collaborated with UAH in HEW development – Used operationally for 24 Core Validation Sites and planned for Fluxnet sites • Resampler – Collaborating with EDC/SDSM&T to develop resampler – Could be used for DAAC services and end user – L2 and L3 regridding support • MODLAND developed QA Tools for Team – Extensions to IDL/ENVI and Unix command line – Bit field handling, etc. HDF-EOS 10
Good things about HDF/HDF-EOS Good things about HDF/HDF-EOS • Made collaboration easier between geographically distant scientists/developers – Self documenting file format allows easy exchange of information between processes • Standard method of representing geolocation HDF-EOS 11
HDF-EOS Gripes (1/2) HDF-EOS Gripes (1/2) • Toolkit doesn't support all HDF objects and access types – Hybrid HDF and HDF-EOS approach used to create/read files – Also need to use SDP toolkit to manipulate metadata • Subsettting on 3/4 dimensional arrays is difficult – ex. take bands 3 & 5 from 7 bands array (3d) and store in 2 band array (3d) – downstream users need to which 2 bands were selected • HDF Specific – No convention for support of bit fields – Performance depends on layout in 3 or 4 dimensional arrays HDF-EOS 12
HDF-EOS Gripes (2/2) HDF-EOS Gripes (2/2) • Swath format does not support external geolocation files – workaround -- two geolocation arrays: one accurate 1 km external file and one 5 km internal array – 5 km array takes up more space and not as accurate • Vendor support growing but still lacking HDF-EOS 13
For More Information For More Information URL: http://modis.gsfc.nasa.gov/ HDF-EOS 14
MODIS Land Data Operational Product Evaluation (LDOPE) Tools Release 1.4 April 30, 2004 Land Processes Distributed Active Archive Center (LP DAAC)
MODIS Overview. The Moderate ... (HDF-EOS) The MODIS Long Name (i.e ... The high level MODIS Land products distributed from LP DAAC are produced at various ...
The MODIS Swath Reprojection Tool reads MODIS swath HDF-EOS files and produces binary HDF-EOS Grid or GeoTiff ... ORNL DAAC MODIS Land Products Subsetting ...
Tool : Description : Platforms : MODIS Reprojection Tool (MRT) a software tool for reading data files in HDF-EOS format, specify a geographic ...
MODIS Data Tools Available Through ... The MRT provides reading of data files in HDF-EOS format (MODIS ... contained within the MODIS land products HDF-EOS ...
MODIS Land Surface Temperature Products ... MODIS LST products ... System (HDF-EOS) format files. HDF, ...
MODIS Land Product ASCII Data. Description of File. File Content: Data as read from MODIS Land Product HDF-EOS data files. These data are the starting ...
The moderate-resolution imaging spectroradiometer ... LANCE-MODIS – Land Atmosphere ... Most of the data is available in the HDF-EOS format — a variant ...
Moderate Resolution Imaging Spectroradiometer (MODIS) With the launch of the Moderate Resolution Imaging Spectroradiometer (MODIS) in December 1999, a new ...