NASA's Earth Science Data and Information Systems (ESDIS) Standards Coordination Office (ESCO) conducts reviews of proposed standards, practices, and technical information relevant to the ESDIS mission. Documents are reviewed as part of the ESDIS Project's standards process. Approved documents are published and listed on the Earthdata Standards Requirements and References page.

Reviewer comments from the initial review have been addressed and incorporated into the current document status. This follow-up edited version is provided to ensure that initial comments have been adequately addressed and is open to both past and new reviewers. You are invited to review these proposed terms and definitions in the context of your experience with the Earth Observing System Data and Information System (EOSDIS) and cloud-optimized data formats. 

ESCO is conducting a review of Zarr storage specification version 2: Cloud-optimized persistence using Zarr. You are invited to review the document in the context of your experience with Earth science data, for its suitability for operational use.  Your insights will help improve this document, and determine whether it should be adopted as a NASA Convention  for Earth Science data producers.

This review is intended for the community of Earth science data users who may benefit from the adoption of the Zarr cloud-optimized storage format for data access and scientific computing.  A clear understanding of both the advantages and limitations of this format are necessary to best serve these end user communities.  

If approved, these recommendations will serve as a NASA Convention (i.e. a specification in common use among some members of the NASA ESDS community).

If you or your team member can review this document, please send names, email addresses, and Earthdata login usernames to  The ECSO Staff will add your names as reviewers in the Jama system.  You may also send any questions about the review to the ESCO staff at

All review comments are due by  

Review Instructions

The role of the ESDIS Standards Coordination Office (ESCO) is to conduct a review of this document by soliciting comments from a cross section of the Earth Science community.

Reviewers are invited to read the document and provide feedback to help us improve the document.  We also invite you to answer the review questions at the end of the document. ESCO recognizes that not all reviewers will be familiar with all of the content of the document.  Reviewers are welcome to review only those parts of the document that they have experience with.  You only need to answer questions applicable to you.  Additional comments are welcome.

ESDIS uses the Jama online document review system to collect community comments on proposed standards, practices and technical information submitted to ESCO for review. 

Preferred Method: Jama

  1. Read and provide comments about the document via Jama here:
  2. For more details on using Jama, see the information at the bottom of this page.

Alternative Method: Word/Email

Offline reviews, where you download the document and review questions, then respond via email, are also accepted.

  1. Download the document:
  2. Use the Track Changes tool in Microsoft Word to mark suggested changes or make comments.
  3. Provide additional feedback by answering the review questions at the end of the document.
  4. Alternatively, if there aren't too many comments, you can submit your review responses in an email.
  5. Send your feedback to the ESCO at

Additional instructions for Jama reviewers

The benefit of using the Jama system is that you can easily comment on specific portions of the document and can see comments provided by others.

If you already have access to the NASA Earthdata Jama system, please contact ESCO at and let us know your Earthdata Login username so we can add to this review. Once you are registered, you will receive an email from Jama with instructions on how to access the review. Use your Earthdata Login username and password to log in to Jama.

Access to Jama

If you do not already have a Jama account but wish to use the Jama system, you can request an account at the Earthdata Service Desk - select JAMA/RMS as the productivity tool, View/Read as the access level, and say that you wish to participate in this review as the reason for access. Alternatively, you may email the ESCO staff at for help in creating a Jama account.

You will need an Earthdata Login account to access Jama.   Earthdata Login account creation and username/password recovery can be done at

Jama Resources

NOTE: Information on this page is subject to change.

Thank you!