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Glossary

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Version 11

ESDS Term Definition, Context, or Usage (within ESDS) Example or Source (of definition, context, or usage)
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Acquisition Strategy Meeting
(ASM)
An ASM is a forum where senior Agency management reviews major acquisitions in programs and projects before authorizing significant budget expenditures. The ASM is held at the Mission Directorate/Mission Support Office level, implementing the decisions that flow out of the earlier Agency acquisition strategy planning. The ASM is typically held early in Formulation, but the timing is determined by the Mission Directorate. The ASM focuses on considerations such as impacting the Agency workforce, maintaining core capabilities and make-or-buy planning, and supporting Center assignments and potential partners. EOSDIS Data System Interfaces
Algorithm A formula or set of steps used, sometimes repetitively, to solve a problem. Algorithms implemented as software are delivered to the Science Investigator-led Processing System (SIPS) or to the Sciene Data Processing Segment (SDPS) by a science investigator (principal investigator, team leader, or Interdisciplinary Investigator) to use as primary tools in the generation of science products. The term includes executable code, source code, job control scripts, and documentation. Definition from Glossary of Terms for ECS Project
Algorithm Theoretical Basis Document
(ATBD)
ATBDs are developed for EOS instrument products, although some ATBDs address more than one product, and some products are addressed by more than one ATBD. ATBDs typically provide the theoretical basis, both the physical theory and the mathematical procedures and possible assumptions being applied, for the calculations that have to be made to convert the radiances received by the instruments to geophysical quantities. The geophysical quantities are then available to the scientific community for studies of the various characteristics of the Earth system. Definition from NASA Earth Observing System Project Science Office
Ancillary Data Data which are not obtained from the spacecraft itself (usually provided in the science telemetry) and have the primary purpose to serve the processing of instrument data. This can be divided into data referred to as spacecraft ‘engineering’, ‘core housekeeping’ or ‘subsystem’ data obtained from other parts of the platform and includes parameters such as orbit position and velocity, attitude and its range of change, time, temperatures, pressures, jet firings, water dumps, internally produced magnet fields, and other environmental measurements.
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Application Programming Interface
(API)
According to Wikipedia, "In computer programming, an application programming interface (API) is a set of routines, protocols, and tools for building software and applications. An API expresses a software component in terms of its operations, inputs, outputs, and underlying types, defining functionalities that are independent of their respective implementations, which allows definitions and implementations to vary without compromising the interface. A good API makes it easier to develop a program by providing all the building blocks, which are then put together by the programmer. An API may be for a web-based system, operating system, or database system, and it provides facilities to develop applications for that system using a given programming language." As examples in EOSDIS, the Common Metadata Repository (CMR) and the Global Imagery Services (GIBS) provide an APIs to support client developers. Definition from Wikipedia - Application Programming Interface
Archive The archive stores data products, guaranteeing their preservation for future use. This function includes all operations to identify, store and retrieve the data and ensure their integrity. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Archiving, Distribution and User Services Requirements Document
(ADURD)
This document provides generic requirements for data archiving, data distribution and user services for EOSDIS-supported data. EOSDIS Data System Interfaces
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Browse Image Visual representation of a product (as an image) to help and support product selection in the frame of the user service facility. Synonyms are: Browse, Quick-look, and Preview. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Browse Data 1. Subsets of data set other than the directory and metadata that facilitates user selection of specific data having the required characteristics. For example, for image data, browse data could be a single channel of multi-channel data, and with degraded resolution. The form of browse data is generally unique for each type of data set and depends on the nature of the data and the criteria used for data selection within the related science discipline.

2. Data produced primarily to provide other investigators with an understanding of the type and quality of data available. Typically, browse data sets are limited in size or resolution. The specific form of browse data depends on the type of instrument or discipline with which the browse data is related. Browse data is sometimes considered to be a sample of available data.

3. Browse data facilitates access to real-time or priority playback data which receive minimal processing and are forwarded to the user for his review/use. The user may provide additional processing to suit his requirements.
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
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Calibration The process of quantitatively defining the system responses to known, controlled signal inputs. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Calibration Data The collection of data required to perform calibration of the instrument science data, instrument engineering data, and the spacecraft or platform engineering data. It includes pre-flight and in-flight calibration measurements, calibration equation coefficients derived from calibration software routines, and ground truth data that is to be used in the data calibration processing routine. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Collection See Data Set Series
Collection or aggregate metadata These are metadata elements that describe an entire set of data products or files. Values of collection metadata apply to all of the products in a specific collection. Collections may represent the same release of any given data product, sets of data generated during an experiment, a campaign or an algorithmic test ESDIS Metadata Standards
Community Capabilities Community capabilities provide specialized and innovative services to data users and/or research products offering new scientific insight. ESDIS Community Data Systems Programs
Core Capabilities The core capabilities provide the basic infrastructure for robust and reliable data capture, processing, archiving, and distributing a set of data products to a large and diverse user community. ESDIS Community Data Systems Programs
Critical Design Reviews
(CDRs)
CDRs evaluate the integrity of the program integrated design, including its projects and ground systems. CDRs also help meet mission requirements with appropriate margins and acceptable risk within cost and schedule constraints. CDRs also determine if the integrated design is appropriately mature to continue with the final design and fabrication phase. EOSDIS Data System Interfaces
Critical Events Readiness Reviews
(CERRs)
CERRs evaluate the readiness of the program and its projects to execute a critical event during the flight operations phase of the life cycle. EOSDIS Data System Interfaces
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Data Scientific or technical measurements, values calculated therefrom, observations, or facts that can be represented by numbers, tables, graphs, models, text, or symbols which are used as a basis for reasoning and further calculation.

For NASA's Earth Science Program and according to the NASA Earth Science Data & Information Policy, the term 'data' includes observation data, metadata, products, information, algorithms, including scientific source code, documentation, models, images, and research results.
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0

NASA Earth Science Data & Information Policy
Data Assimilation Data assimilation is the process by which observations are incorporated into a computer model of a real system. Definition from Wikipedia - Data assimilation
Data Collection See: Data Set Series
Data Format Control Documents
(DFCDs)
Data Format Control Documents (DFCDs), and other data format documents (e.g., Data Format Requirements Documents (DFRDs)), define the formats of data units that are transferred across an interface and the control codes used in the data formats. EOSDIS Data System Interfaces
Data Management As defined for an OAIS entity that contains the services and functions for populating, maintaining, and accessing a wide variety of information. Some examples of this information are catalogs and inventories on what may be retrieved from Archival Storage, processing algorithms that may be run on retrieved data, Consumer access statistics, Consumer billing, Event Based Orders, security controls, and OAIS schedules, policies, and procedures. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Data Maturity Levels Beta
Products intended to enable users to gain familiarity with the parameters and the data formats.

Provisional
Product was defined to facilitate data exploration and process studies that do not require rigorous validation. These data are partially validated and improvements are continuing; quality may not be optimal since validation and quality assurance are ongoing.

Validated
Products are high quality data that have been fully validated and quality checked, and that are deemed suitable for systematic studies such as climate change, as well as for shorter term, process studies. These are publication quality data with well-defined uncertainties, but they are also subject to continuing validation, quality assurance, and further improvements in subsequent versions. Users are expected to be familiar with quality summaries of all data before publication of results; when in doubt, contact the appropriate instrument team.

  • Stage 1 Validation: Product accuracy is estimated using a small number of independent measurements obtained from selected locations and time periods and ground-truth/field program efforts.
  • Stage 2 Validation: Product accuracy is estimated over a significant set of locations and time periods by comparison with reference in situ or other suitable reference data.
Spatial and temporal consistency of the product and with similar products has been evaluated over globally representative locations and time periods.
Results are published in the peer-reviewed literature.
  • Stage 3 Validation: Product accuracy has been assessed. Uncertainties in the product and its associated structure are well quantified from comparison with reference in situ or other suitable reference data. Uncertainties are characterized in a statistically robust way over multiple locations and time periods representing global conditions.
 Spatial and temporal consistency of the product and with similar products has been evaluated over globally representative locations and periods.
 Results are published in the peer-reviewed literature.
  • Stage 4 Validation: Validation results for stage 3 are systematically updated when new product versions are released and as the time-series expands.

Definition from NASA Earth Science - Data Maturity Levels
Data Model An Earth science metadata model, which supports the data standardization necessary for total system interoperability within a heterogeneous, open systems environment. The Data Model includes diagrams, which graphically illustrate the relationships of classes, the attributes contained within the classes, the characteristics of the relationships between classes, and the attribute specifications. Definition from Glossary of Terms for ECS Project
Data Products A processed collection (one or more) of parameters packaged with associated ancillary and labeling data, and formatted with uniform temporal and spatial resolution. (For example, the collection of data distributed by a data center or subsetted by a data center for distribution.) There are two types of data products:

Standard: A data product produced at a DAAC by a community consensus algorithm for a wide community of users.

Special: A data product produced at a science computing facility by a research algorithm for later migration to a community consensus algorithm and can be archived and distributed by a DAAC.
Definition from Glossary of Terms for ECS Project
Data Quality See: Quality Indicator
Data Services The EOSDIS data centers process, archive, document, and distribute data from NASA's past and current Earth-observing satellites and field measurement programs. Each center serves a specific Earth system science discipline and provides users with data products, services, and data-handling tools unique to the center's specialty. User services include:

  • Assistance in selecting and obtaining data
  • Access to data-handling and visualization tools
  • Notification of data-related news
  • Technical support and referrals
EOSDIS - ESDIS Project
Data Set or Dataset A logically meaningful grouping or collection of similar or related data. Data having all of the same characteristics (source or class of source, processing level, resolution, etc.) but different independent variable ranges and/or responding to a specific need are normally considered part of a single data set. A data set is typically composed by products from several missions, gathered together to respond to the overall coverage or revisit requirements from a specific group of users.

In the context of EO data preservation a data set consists of the data records of one mission, sensor, and product type and the associated knowledge(information, tools). See collection.
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Data Set Documentation Information describing the characteristics of a data set and its component granules, including format, source instrumentation, calibration, processing, algorithms, etc. EOS Glossary and list of Acronyms/Abbreviations
Data Set Series or Dataset Series Collection of datasets sharing the same product specification. They are synonym of EO collections. They are named dataset series as they may be mapped to ‘dataset series’ according to the terminology defined in ISO 19113, ISO 19114 and ISO 19115. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Data User Guide A document, either on-line or hardcopy, containing the necessary information for the correct usage of the data. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Data Visualization See: Visualization
Datacasting Datacasting is an RSS/GeoRSS-based technology for distributing Earth Science data
Decommissioning Review
(DR)
DRs evaluate the readiness of the program and its projects to conduct closeout activities, including final delivery of all remaining program/project deliverables and safe decommissioning/disposal of space flight systems and other program/project assets. EOSDIS Data System Interfaces
Disposal Readiness Review
(DRR)
DRRs evaluate the readiness of the project and the flight system for execution of the spacecraft disposal event. EOSDIS Data System Interfaces
Derived Products Derived products are higher level products (level 1b through 4) where calibration and geo-location transformations have been applied to generate sensor units, and/or algorithms have been applied to generate gridded geophysical parameters. 423-SPEC-001 NASA Earth Science Data Preservation Content Specification
Detailed Mission Requirements
(DMR)
DMRs include Mission-Specific Requirements Documents (MSRDs) and mission requirement documents (e.g., Ground System Requirements Documents (GSRDs), and Mission Operations Requirements Documents (MORDs)). DMRs contain the results of the requirements identification and derivation activities and provide the basis for system design for individual missions. EOSDIS Data System Interfaces
Discipline A field of study such as oceanography, meteorology, geology, or marine biology. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Discovery Any service that helps the user to identify and locate EO resource starting from his needs. See also Search and Discovery. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Distributed Architecture The allocation of EOSDIS elements to various locations to take best advantage of each location's different institutional capabilities and science expertise. EOSDIS System Description
Distributed Active Archive Center
(DAAC)
EOSDIS is designed as a distributed system, with major facilities at Distributed Active Archive Centers (DAACs) located throughout the United States. These institutions are custodians of EOS mission data and ensure that data will be easily accessible to users. The EOSDIS DAACs process, archive, document, and distribute data from NASA's past and current Earth-observing satellites and field measurement programs. Acting in concert, the DAACs provide reliable, robust services to users whose needs may cross the traditional boundaries of a science discipline, while continuing to support the particular needs of users within the discipline communities. User services include:

  • Assistance in selecting and obtaining data
  • Access to data-handling and visualization tools
  • Notification of data-related news
  • Technical support and referrals
Earthdata Website
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Earth Observing System Data and Information System
(EOSDIS)
The Earth Observing System Data and Information System (EOSDIS) is a key core capability in NASA’s Earth Science Data Systems Program. It provides end-to-end capabilities for managing NASA’s Earth science data from various sources – satellites, aircraft, field measurements, and various other programs. For the EOS satellite missions, EOSDIS provides capabilities for command and control, scheduling, data capture and initial (Level 0) processing. These capabilities, constituting the EOSDIS Mission Operations, are managed by the Earth Science Mission Operations (ESMO) Project. NASA network capabilities transport the data to the science operations facilities.
The remaining capabilities of EOSDIS constitute the EOSDIS Science Operations, which are managed by the Earth Science Data and Information System (ESDIS) Project. These capabilities include: generation of higher level (Level 1-4) science data products for EOS missions; archiving and distribution of data products from EOS and other satellite missions, as well as aircraft and field measurement campaigns. The EOSDIS science operations are performed within a distributed system of many interconnected nodes (Science Investigator-led Processing Systems, or SIPS; and Distributed Active Archive Centers, or DAACs) with specific responsibilities for production, archiving, and distribution of Earth science data products. The distributed data centers serve a large and diverse user community (as indicated by EOSDIS performance metrics) by providing capabilities to search and access science data products and specialized services.
Wikipedia - EOSDIS - Data Center Search & Order Tools
Earth Science Data and Information System (ESDIS) Project The Earth Science Data and Information System (ESDIS) Project is a part of the Earth Science Projects Division under the Flight Projects Directorate at Goddard Space Flight Center. The ESDIS Project manages the science systems of the Earth Observing System Data and Information System (EOSDIS). See Earth Observing System Data and Information System (EOSDIS) ESDIS
Earth Science Data Type
(ESDT)
Each type of science data collected by an instrument aboard a satellite supported by the ECS is given a data type name to be stored or archived in the ECS inventory (e.g., MISR001.) ESDTs also define the Services which can be applied to the data and the metadata associated with the data. In addition, ESDTs are defined for all data referenced in the ECS inventory and this includes some non-satellite data, and some non-instrument data (e.g., science software archive packages, algorithm packages, pge tar files, and delivered algorithm packages). Definition from Glossary of Terms for ECS Project
Earth Science Mission Operations
(ESMO)
The Earth Science Mission Operations (ESMO) Project is responsible for spacecraft maintenance and operations for Earth Science missions conducted by the Earth Science Projects Division at the Goddard Space Flight Center. The ESMO Project plays a significant role during the mission life cycle; from the formulation and approval phases through the implementation and evaluation phases, and eventual deactivation. The Project's role is to ensure the health and safety of the missions it manages by fulfilling the primary operational requirements for each mission, and providing the scientific community with high-quality data products in a timely manner. It also serves as a focal point for the mission on-orbit operations and the definition of support services required. ESMO

Engineering Data Data which describe the physical condition and operation of the platform and instruments on the platform. Parameters might include temperatures at specific points, filter(s) in use, switch settings, memory data, etc. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Engineering Metadata Metadata used by the investigation team to record information about the sensor and the observation. It may be extraneous to scientific uses or it may be derivable to science metadata, such as ‘filter=4’ which could resolve to a spectral range or polarization. Definition from Vocabulary for Virtual Observatories and Data Systems; Hourclé, J.A. and King, T.A. (pdf)
EOSDIS Core System
(ECS)
The infrastructure which provides NASA's Earth Observing System (EOS) and other U.S. and international scientists a broad range of desktop services from 12 science data centers, the Distributed Active Archive Centers (DAACs), operated by NASA and other agencies. The ECS infrastructure also supports exchange of data and research results within the science community, across multiple agencies and internationally. ECS is the evolutionary base for accelerating the pace of Earth science research.
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Flight Readiness Review
(FRR)
FRRs evaluate the readiness of the program and its projects, ground systems, personnel, and procedures for a safe and successful launch and flight/mission. EOSDIS Data System Interfaces
Footprint Geographic area covered by the instrument observation and its derived products. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Formulation Agreement
(FA)
The FA is prepared by the project to establish the technical and acquisition work that needs to be conducted during Formulation and defines the schedule and funding requirements during Phase A and Phase B for that work. EOSDIS Data System Interfaces
Formulation Authorization Document
(FAD)
The FAD is issued by the MDAA to authorize the formulation of a program whose goals will fulfill part of the Agency's Strategic Plan and Mission Directorate strategies and establish the expectations and constraints for activity in the Formulation Phase. In addition, a FAD or equivalent is used to authorize the formulation of a project. (See Appendix E.) EOSDIS Data System Interfaces
Forward Processing A term used in data processing when the data is moving from version to version.
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Granule The smallest aggregation of data which is independently managed (i. e. described, inventoried, retrievable). Granules may be managed as logical granules and/or physical granules. See also Scene.

Note that granule is often equivalent to Data Set.
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Granule Metadata These are metadata elements that describe a single granule of a data product. Values of granule metadata apply to all of the data in that one granule. Typical metadata in this category describe spatial and temporal extent of the data as well as the quality and lineage of the data. See also Granule. Definition from Glossary of Terms for ECS Project

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Hierarchical Data Format
(HDF)
The Hierarchical Data Format (HDF) is designed to facilitate managing and sharing scientific data. HDF includes two formats (HDF4 and HDF5), software for accessing data in HDF formats, and applications for working with HDF data. HDF is designed for efficient storage and access of high volume, complex data, and for mixing varieties of data types in a single container. ESDIS Data Format Standards
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Information System See: Earth Observing System Data and Information System (EOSDIS)
Any system composed of hardware, software, and operational procedures components required to process, store, and/or transmit data.
An integrated combination of software, hardware, and operational procedures that provides a useful capability. An information system is generally software intensive.
EOS-AM Spacecraft Glossary
Ingestion The ingestion function accepts data from different sources: ground segment reception, processing or data migration elements. The received data is quality checked and metadata including browse images are obtained from the data. The data and meta-data form a data product. The product is consistently submitted to archiving and cataloguing. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Instrument Calibration The instrument calibration function is the determination of parameters describing instrument characteristics. They are to be used by the instruments and ground processing to generate calibrated and comparable physical values. These parameters vary for different instruments and modes. And they may vary over time in the long run (degradation). Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Inter-Project Agreement
(IPA)
IPAs are agreements between ESDIS and projects not managed by ESDIS. Generally, the projects involved agree on an exchange of support services and data. From the interface control viewpoint, these agreements identify the need for an interface and the scope of the interface. EOSDIS Data System Interfaces
Interface Control Documents
(ICDs)
ICDs are used to record design agreements for the interfaces between participating organizations. ICDs provide a means to evaluate and control all mutually interdependent and/or interacting design parameters of the interface. EOSDIS Data System Interfaces
Interface Requirement Documents
(IRDs)
IRDs define the requirements for data exchanges across an interface between separately managed systems or subsystems. The requirements statements in IRDs are derived directly from project requirements documents. EOSDIS Data System Interfaces
Interoperability The ability of different information technology systems and software applications to communicate, exchange data, and use the information that has been exchanged. In Earth observation it includes e.g. interoperable discovery and access, i.e. the capability of the user interface and administrative software of one instance of a catalogue service to interact with other instances of catalogue services.
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Inventory A uniform set of descriptions of granules from one or more data sets with information required for selecting and obtaining a subset of those granules. Granule descriptions typically include temporal and spatial coverage, status indicators, and physical storage information. An inventory can describe physical granules, logical granules, or both, including a mapping between them if they are not identical.
Note: The inventory is not the granules themselves, but rather the descriptive data for each of them, specifically used.
Definition from Glossary of Terms for ECS Project
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Key Decision Point
(KDP)
A KDP is the event at which the Decision Authority determines the readiness of a program/project to progress to the next phase of the life cycle (or to the next KDP). EOSDIS Data System Interfaces
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Launch Readiness Review
(LRR)
LRRs evaluate a program/project and its ground, hardware, and software systems for readiness for launch. EOSDIS Data System Interfaces
Launch Vehicle
(LV)
LVs are rockets that send people or things into space. EOSDIS Data System Interfaces
Level 0 See: Processing Levels
Level 1A Standard Product See: Processing Levels
Level 1B Standard Product See: Processing Levels
Level 1C Standard Product See: Processing Levels
Level 2 Standard Product See: Processing Levels
Level 3 Standard Product See: Processing Levels
Level 4 Standard Product See: Processing Levels
Long Term Preservation The act of maintaining information in a correct and independently understandable form over the long term, i.e. a period of time long enough to be concerned with the impact which changing technologies, including support for media and data formats, and changing user communities will have on the information being held in a repository. See also Preservation.

Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
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Metadata Data about data, contained in data sets, and which provides an understanding of the content and utility of the data set. Metadata may be used to select on data for a particular scientific investigation.

Metadata is intended as information describing significant aspects of a resource (Earth Observation space data in this context). They are created for the purposes of data search, discovery and access management and may exist at various levels, typically from data collection through to the individual variables of each data file in a collection.
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Metadata repository A metadata repository, commonly referred to as a catalog, is accessed by client applications that support user queries. 423-RQMT-003 Metadata Requirements – Base Reference for NASA Earth Science Data Products
Mission Concept Review
(MCR)
MCRs evaluate the feasibility of the proposed mission concept(s) and its fulfillment of the program's needs and objectives. MCRs also determine whether the maturity of the concept and associated planning are sufficient to begin Phase A. EOSDIS Data System Interfaces
Mission Definition Review
(MDR)
MDRs evaluate the credibility and responsiveness of the proposed mission/system architecture to the program requirements and constraints, including available resources. MDRs also determine whether the maturity of the project's mission/system definition and associated plans are sufficient to begin Phase B. EOSDIS Data System Interfaces
Mission Readiness Review
(MRR)
MRRs evaluate the readiness of the program and its projects, ground systems, personnel, and procedures for a safe and successful launch and flight/mission. EOSDIS Data System Interfaces
Mission Readiness Test Plan
(MRTP)
The MRTP documents the strategy that will be used to verify and ensure that all system components working together meet design specifications and requirements for the mission. EOSDIS Data System Interfaces
Modeling An investigative technique that uses a mathematical or physical representation of a system or theory that accounts for all or some of its known properties. Models are often used to test the effects of changes of system components on the overall performance of the system. EOS Glossary and list of Acronyms/Abbreviations
Mosaic A composite of images. EOSDIS LANCE - Rapid Response

Definition from NASA Lunar Mapping and Modeling Project (LMMP) Wiki

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Near Real-Time
(NRT)
NRT is a time delay introduced by automated data processing or network transmission between the occurrence of an event and the use of the processed data. Typically – for meteorological purposes – this is within 3 hours from sensing. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Near Real-Time Data Products NRT data products from MODIS, OMI, AIRS, and MLS instruments in less than 2.5 hours from the Land, Atmosphere Near real-time Capability for EOS (LANCE). EOSDIS Discovering Data
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On-Demand Data Set Collection of products that cannot be predefined, built from single user requests upon need arising. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Operations Agreement
(OA)
Operations Agreements are even lower level, more detailed interface documents that are created to help define the operations use of the interfaces, including such things as addresses, phone numbers, and names of responsible personnel. These documents are not intended for project-level development and control. EOSDIS Data System Interfaces
Operational Readiness Review
(ORR)
ORRs evaluate the readiness of the program, including its projects, ground systems, personnel, procedures, and user documentation. ORRs also operate the flight system and associated ground systems in compliance with program requirements and constraints during the operations phase. EOSDIS Data System Interfaces
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Parameter (or Variable) A parameter or variable is any of a set of physical properties whose values determine the characteristics or behavior of something, for example, parameters of the atmosphere such as temperature, pressure, and density. These terms are used interchangeably. The GCMD uses the term variable and NSIDC uses the term parameter. Definition from Merrian Webster - Parameter
Preliminary Design Review
(PDR)
PDRs evaluate the completeness/consistency of the program's preliminary design, including its projects, in meeting all requirements with appropriate margins, acceptable risk, and within cost and schedule constraints, and to determine the program's readiness to proceed with the detailed design phase of the program. EOSDIS Data System Interfaces
Post-Flight Assessment Review
(PFAR)
PFARs evaluate how well mission objectives were met during a human space flight mission. PFARs also evaluate the status of the flight and ground systems, including the identification of any anomalies and their resolution. EOSDIS Data System Interfaces
Post-Launch Assessment Review
(PLAR)
PLARs evaluate the in-flight performance of the program and its projects. PLARs also determine the program's readiness to begin the operations phase of the life cycle and transfer responsibility to the operations organization. EOSDIS Data System Interfaces
Preservation Actions on individual or multi-mission datasets with the goal to ensure the "EO Missions/Sensors Preserved Data Set" integrity over time, its discoverability and accessibility, and to facilitate its (re)-use in the long term. Examples are data record improvement and consolidation. Preservation is one of the tasks of data curation. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Processing The processing function generates higher-level products from lower level products and auxiliary products. The processing is performed by core algorithms supplemented by administrative functions (e.g. formatting). The algorithms are version controlled. Processing is capable to produce the desired products systematically or on request. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Processing Levels Raw Data
The physical telemetry payload data as received from the satellite, i.e. a serial data stream without de-multiplexing.

Level 0
Reconstructed unprocessed data at full space-time resolution with all available supplemental information to be used in subsequent processing (e.g. ephemeris, health and safety) appended.

Level 1A
Reconstructed unprocessed data at full resolution, time-referenced, and annotated with ancillary information, including radiometric and geometric calibration coefficients and geo-referencing parameters (e.g. ephemeris) computed and appended but not applied to the Level 0 data.

Level 1B
Radiometrically corrected and calibrated data in physical units at full instrument resolution as acquired.

Level 1C
L1B data orthorectified, re-sampled to a specified grid

Level 2
Derived geophysical parameters (e.g. sea surface temperature, leaf area index) at the same resolution and location as Level 1 source data.

Level 3
Data or retrieved geophysical parameters which have been spatially and/or temporally re-sampled (i.e. derived from Level 1 or 2 products), usually with some completeness and consistency. Such re-sampling may include averaging and compositing.

Level 4
Model output or results from analyses of lower level data (i.e., variables that are not directly measured by the instruments, but are derived from these measurements; could be derived from multiple instrument measurements).
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Product A permanently archived set of output data generated by the science software. Definition from Glossary of Terms for ECS Project
Product Application Useful references to published articles about the use of the data and user feedback received by the science and instrument teams about the products. Includes reports of any peculiarities or notable features observed in the products. 423-SPEC-001 NASA Earth Science Data Preservation Content Specification
Product Generation Algorithm Detailed discussion of processing algorithms, outputs, error budgets and limitations. 423-SPEC-001 NASA Earth Science Data Preservation Content Specification
Product Quality Description of the impact to product quality due to issues with computationally intensive operations (e.g., large matrix inversions, truncation and rounding). 423-SPEC-001 NASA Earth Science Data Preservation Content Specification
Product Specification Document
(PSD)
A document that provides the technical specifications relating to the formatting and content of a particular data product. EOSDIS Data System Interfaces
Product Team Names of key science team leads and product team members (development, help desk and operations), roles, performing organization, contact information, sponsoring agencies or organizations and comments about the products. 423-SPEC-001 NASA Earth Science Data Preservation Content Specification
Production Readiness Review
(PRR)
PRRs evaluate the readiness of system developer(s) to produce the required number of systems within defined project constraints for projects developing multiple similar flight or ground support systems. PRRs also evaluate the degree to which the production plans meet the system's operational support requirements. EOSDIS Data System Interfaces
Project Plan The Project Plan contains the technical approaches and management plans to implement the project requirements. It defines, at a high level, the scope of the project, the implementation approach, the environment within which the project operates, and the baseline commitments of the program and project. (from NPR 7120.5D) EOSDIS Data System Interfaces
Provenance Information The information that documents the history of the content information. This information tells the origin or source of the content information, any changes that may have taken place since it was originated, and who has had custody of it since it was originated. Examples of provenance information could be the principal investigator who recorded the data, and the information concerning its storage, handling, and migration. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
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Quality Indicator A quality indicator shall provide sufficient information to allow all users to readily evaluate the “fitness for purpose” of the data or derived product. A Quality Indicator may be a number, set of numbers, graph, uncertainty budget, or a simple “flag”. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Quality Information Secondary data required to assess the primary data set’s fitness for purpose, e.g. calibration and validation data and quality control results. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Quick-Look Data A data product, usually related to a Level 1 or higher Standard Data Product, which is generated and distributed in near-real time. EOS Glossary and list of Acronyms/Abbreviations
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Raw Data See: Processing Levels
Reprocessing Reprocessing is a specialization of processing where a complete product collection is systematically generated to obtain a new revision using archived lower level products. Re-processing is normally initiated after an improved processing algorithm is released, or if a reformatting of the information content is required. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Requirements Documents
(RQMT)
RDs are detailed requirements allocated from the project to the next lower level of the project. EOSDIS Data System Interfaces
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Safety and Mission Success Reviews
(SMSR)
SMSRs prepare Agency safety and engineering management to participate in program final readiness reviews preceding flights or launches, including experimental/test launch vehicles or other reviews as determined by the Chief, Safety and Mission Assurance. SMSRs also provide the knowledge, visibility, and understanding necessary for senior safety and engineering management to either concur or nonconcur in program decisions to proceed with a launch or significant flight activity. EOSDIS Data System Interfaces
Scene Subset of an instrument acquisition data segment, cut by time i.e. across-swath. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Science Data Management Plan
(SDMP)
The SDMP describes how the program will manage the scientific data generated and captured by the operational mission(s). The SDMP also includes descriptions of how data will be generated, processed, distributed, analyzed, and archived. EOSDIS Data System Interfaces
Science Data Product Software
(SDPS)
Science data product generation software and software documentation. Source code used to generate products at all levels in the science data processing system. 423-SPEC-001 NASA Earth Science Data Preservation Content Specification
Science Data Product Validation Datasets and documentation. Accuracy of products, as measured by validation testing, and compared to accuracy requirements. Description of validation process, including identification of validation data sets, measurement protocols, data collection, analysis and accuracy reporting. 423-SPEC-001 NASA Earth Science Data Preservation Content Specification
Science Data Products Algorithm Inputs Identify all ancillary data or other data sets used in generation or calibration of the data or derived product at all levels 423-SPEC-001 NASA Earth Science Data Preservation Content Specification
Science Data Software Tools Product access (reader) tools. Software source code that would facilitate use of the calibration data, ancillary data and the data products at all levels. 423-SPEC-001 NASA Earth Science Data Preservation Content Specification
Science Investigator-led Processing System
(SIPS)
Most of the EOS standard products are produced at facilities under the direct control of the instrument Principal Investigators/Team Leaders (PIs/TLs) or their designees. These facilities are referred to as Science Investigator-led Processing Systems (SIPS). The SIPS are geographically distributed across the United States and are generally, but not necessarily, collocated with the PIs/TLs’ Scientific Computing Facilities. Products produced at the SIPS using investigator-provided systems and software are sent to appropriate DAACs for archival and distribution. Level 0 Data Products and Ancillary Data that begin the processing sequence are stored at the DAACs and retrieved by the SIPS.
Search and Discovery The procedure to search an archive based on specific search criteria (search) and to obtain information on available products (discovery). Data search and discovery are enabled by generating and maintaining searchable metadata and browse image catalogues, as well as providing a catalogue service for making the catalogue accessible (e.g. OGC CSW) and mechanisms to retrieve and present the information contained in the catalogue, e.g. via the graphic user interface of a data portal.

During the discovery following a data search the user finds data based on his search criteria and evaluates if the data found are suitable for his application ('fit for purpose') by e.g. viewing the browse image, evaluating metadata such as coverage, quality information, or cost and licensing conditions. He may then decide to retrieve the data.

Search and discovery as well as retrieval are components of data access.
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Sensor Device which transmits an output signal in response to a physical input stimulus as voltage. In Earth observation a distinction between passives sensors, such as radiometers, and active sensors, such as radars, is common. Earth observation sensors – or instruments – are operated from different ground-/water-based, airborne, or spaceborne platforms. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Series/Collection A grouping of science data that all come from the same source, such as a modeling group or institution. Series/collections have information that is common across all the datasets/granules they contain. 423-RQMT-003 Metadata Requirements – Base Reference for NASA Earth Science Data Products
Series/Collection metadata Metadata elements that describe an entire set of data files. Values of series/collection metadata apply to all of the files in a specific aggregate. Series/collection metadata may represent the same release of any given file, sets of data generated during an experiment, a campaign or an algorithm test. 423-RQMT-003 Metadata Requirements – Base Reference for NASA Earth Science Data Products
Spatial Coverage Refers to a geographical area where data was collected, a place which is the subject of a collection, or a location which is the focus of an activity. Spatial coverage can be a point location or an area, the latter usually a specific 'rectangle' (e.g. a bounding box) on a map or a region. This is described using geospatial coordinates for a point or an area (for example, latitude and longitude), or through the use of place or regional names (for example, Barrow Island; Gippsland, Australia). Regional names may be based on legal jurisdiction (for example, South Australia). Australian National Data Service - Content Providers Guide - Spatial and Temporal Coverage
Standard Product Standard Products are products that are acquired systematically and products that are generated by systematic processing.
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Standing Review Board
(SRB)
The SRB is responsible for conducting independent reviews (life cycle and special) of a program/project and providing objective, expert judgments to the convening authorities. The reviews are conducted in accordance with approved Terms of Reference (ToR) and life-cycle requirements per this document and NPR 7123.1. EOSDIS Data System Interfaces
Stewardship The responsibility for planning, management and certification of digital EO data sets throughout the mission phases and to ensure adequate funding. It includes curation and preservation activities. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
Subsetting The extraction of a multi-dimensional rectangular array of pixels from a single data granule, where consecutive pixels are extracted from each array dimension. For each dimension, the size of the pixel array is characterized by the starting pixel location and the number of pixels to extract. Definition from Glossary of Terms for ECS Project
Swath A swath is defined as the area covered by the spatial samples collected during a scan of a spaceborne instrument defined by an incidence angle. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
System Acceptance Review
(SAR)
SARs evaluate whether a specific end item is sufficiently mature to be shipped from the supplier to its designated operational facility or launch site. EOSDIS Data System Interfaces
System Definition Review
(SDR)
SDRs evaluate the credibility and responsiveness of the proposed program requirements/architecture to the Mission Directorate requirements and constraints, including available resources, and allocation of requirements to projects. SDRs also determine whether the maturity of the program's mission/system definition and associated plans are sufficient to begin preliminary design. EOSDIS Data System Interfaces
System Integration Review
(SIR)
SIRs evaluate the readiness of the program, including its projects and supporting infrastructure, to begin system AI&T with acceptable risk and within cost and schedule constraints. EOSDIS Data System Interfaces
System Requirements Review
(SRR)
SRRs evaluate whether the functional and performance requirements defined for the system are responsive to the Mission Directorate requirements on the program and its projects and represent achievable capabilities. EOSDIS Data System Interfaces
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Temporal Coverage A time period during which data was collected or observations made, or a time period that an activity or collection is linked to intellectually or thematically, for example, 1997 to 1998; the 18th century. Australian National Data Service - Content Providers Guide - Spatial and Temporal Coverage
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Uncertainty Non-negative parameter characterizing the dispersion of the quantity values that are being attributed to a measure based on the information used.

Where possible, this should be derived from an experimental evaluation but can also be an estimate based on other information, e.g. experience.
Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
User External person, institution or system that consumes user services (Data Access or Science and Service Exploitation Platform) provided by the payload data ground segment. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
User Satisfaction Data The ESDIS Project is responsible for: Collecting metrics and user satisfaction data to learn how to continue improving services provided to users. ESDIS Project
User Support User support is a function inside the payload data ground segment to support external users to interact with the segment, to handle user registration, inquiries, complaints. This function is usually provided by a help desk. Definition from CEOS-WGISS Glossary of Acronyms and Terms, v1.0
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Validation Stage See: Data Maturity Levels
Variable See: Parameter
Version/Release Number (also Collection) Collection means the same thing as version; however, the MODIS science team uses the term Collection such as in MODIS Collection 5, but NSIDC uses Version as in MODIS Version 5.

Also, GLAS refers to a Release such as Release 33, which is also the same as version or collection. Thus, all three terms mean the same thing depending on which product you are using.
Example:NSIDC MODIS/Terra Snow Cover 5-min L2 Swath 500m, Version 5

Example:NSIDC ICESat/GLAS Data Release Schedules
Visualization Visualization is the study of the visual representation of data, meaning "information that has been abstracted in some schematic form, including attributes or variables for the units of information". Definition from Wikipedia - Data Visualization
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Working Agreement A W/A outlines the working commitments made between the ESDIS Project and another organization for developing, implementing and/or operating portions of the data system. EOSDIS Data System Interfaces
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Last Updated: May 24, 2017 at 5:06 PM EDT

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