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.
How to order MISR data:
The ASDC's MISR Data Sets page (the central location indicated at the top of this page) contains details on each publicly available MISR product, including how to access the data through Earthdata Search, the data pool, and ASDC's OPENDAP system. 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, in which L1 data and certain L2 datasets are distributed.
Obtaining data through the data pool:
The ASDC data pool is an on-line cache of the data products downloadable from the ASDC. See the ASDC's Data Pool page. A free Earthdata account is required to obtain access.
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 page.
Currently available data products:
These are listed on the ASDC's MISR Data Sets page.
Structure and content of MISR data products, and which files you need to order:
The structure of MISR's data products can be referenced via the Data Product Specification (DPS) documents. DPSs for the most recently updated MISR products are found here, while older products are described in a single DPS. MISR's Algorithm Theoretical Basis (ATB) documents are on line at the EOS Project Science Office at NASA Goddard Space Flight Center and describe the algorithms used to derive the content in each product.
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 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. You can also submit a new question through this forum if you don't find the information you need.
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. Note: misr_view is compatible with MISR L1 data and L2 cloud products. It cannot display the new NetCDF L2 and L3 products.
The MISR INteractive eXplorer (MINX) tool is used to retrieve heights of objects in the atmosphere using MISR L1 data. It is also available from GitHub.
The MISR Toolkit contains various command-line utilities to manipulate MISR L1 and L2 cloud data, as well as Python, IDL, and C bindings. It is available from GitHub.
The newer NetCDF MISR products can be read using the free Panoply software available from NASA.
Additional tools are available only through the ASDC.
Details on the MISR data sytem are obtainable through the MISR Science Software web page.