How Terra’s orbital drift will affect MISR data
Terra has completed all mission maneuvers related to maintaining a 10:30 mean local time (MLT) equator crossing, and began drifting to an earlier MLT in April 2021. In October 2022, Terra will have a 10:15 AM MLT crossing, and will continue to drift to earlier MLT. It is possible that some changes compared to the prior 22-year record may be detectable, particularly in observables (such as stratocumulus cloud fraction) that have a strong diurnal cycle, offering novel opportunities for application of MISR data to climate and environmental studies. Also in late 2022, the Terra orbit altitude will be lowered to 694 km. After constellation exit, MISR science observations will continue, with the major impact being that MISR ground tracks will no longer exactly repeat every 16 days. Data products will be associated with the closest path number that was in effect prior to constellation exit to preserve continuity for data users. Imagery will continue to be mapped to the same spatial grids as in the current Level 1, 2, and 3 data products. The Terra orbit changes are not expected to have any significant impacts on MISR data quality. For more information regarding Terra orbital drift, click on the link to the Terra website.
Data access: Quick links
Data access: More information
How to order MISR data:
The ASDC's MISR Data Sets page (the central location indicated at the top of this page) contains a range of useful links, under the "Data" heading. This includes a Workshop Presentation that gives many details about product ordering.
There are low-resolution browse images to assist in selecting products to order. See the Browse Tool on the ASDC's MISR Data Sets page.
MISR's Level 1 and Level 2 data products are produced as full-swath (orbit) granules, which are large. If you need only a small segment of a swath, you can take advantage of the MISR order and customization tool.
The MISR order and customization tool also includes a reformatting feature, which allows delivery of products in conventional HDF-EOS format, rather than MISR's special stacked-block format.
Obtaining data through the data pool:
The data pool is an on-line cache of short-term data products downloadable via FTP from the ASDC. See the ASDC's Data Pool page.
MISR data specially produced or assembled for fast delivery during field campaigns is also available through the data pool, and can be accessed at the ASDC's MISR Data sets
Currently available data products:
These are listed on the ASDC's MISR Data Sets page.
To help in the understanding of MISR's Level 3 global products, an overview of Level 3 imagery is accessible on the ASDC's MISR Data Sets page.
Structure and content of MISR data products, and which files you need to order:
There is a Project Guide on the ASDC's MISR Data Sets page that provides a top-level introductory description of the products and what to order. MISR's Algorithm Theoretical Basis (ATB) documents are on line at the EOS Project Science Office at NASA Goddard Space Flight Center.
MISR's product maturity levels (Alpha, Beta, Provisional, Validated) are described in a separate page.
Detailed documentation of the products (for in-depth users):
For detail needed by those who require an in-depth knowledge of the products, see the Data Products Specifications, Data Quality Statements, and the Data Versioning information (Level1, RCCM, L2TCST, L2TCCL, L2TCAL, L2TCSP, L2AS, L3GRP, L3AL, L3CL, L3AS, L3LS, L3JOINT_AS, L3CFbA, L3CMV) on the ASDC's MISR Data Sets page.
There is a Frequently Asked Questions (FAQ) page accessible at the ASDC's MISR Data Sets page.
History and status of MISR data production:
See the various links in the Processing Information column of the ASDC's MISR Data Sets page. There is information there about the current processing schedule, and about the archived product collections.
Software tools for reading and analyzing MISR data
The primary tool for display and analysis of many types of MISR data is misr_view, which is available from GitHub.
See also the links in the Tools column of the ASDC's MISR Data Sets page. Some of the tools listed there are available only through the ASDC. This includes an ENVI interface and an HDF-EOS to GeoTIFF converter.
Some tools, such as hdfscan, are obtainable through the MISR Science Software web page.