Data Versions

To review the processing and algorithm history for all versions of SMAP data sets, download the following workbooks which get updated on a periodic basis.

SMAP Version History Workbool L1-L3 Products

SMAP Version History Workbook L4 Products


Missing Data Resources


SMAP instrument operations sometimes result in problematic or missing data. Details of these events are maintained on two master lists:

SMAP On-Orbit Events List for Instrument Data Users

Master List of Bad and Missing Data


Naming Conventions


Major Version

Major versions indicate the Series- or Collection-level major version of SMAP data products. Major versions signify that one or more changes have been made that caused a scientific change in the data, including:

  • Change of input data used
  • Change to algorithm or processing software
  • Significant change to file-level metadata

Major version changes typically result in a reprocessing of the entire time series. As shown in the figure below, the major version ID is located in SMAP HDF5 (.h5) data files under the Metadata group and within the DatasetIdentification field .

Figure 1. Major Versions of SMAP Data Products
To find the major version of a SMAP data product, navigate to DatasetIdentification within the Metadata group of any SMAP HDF5 (.h5) data file. The ECSVersionID = 004 indicates that these are Version 4 data.

Composite Release IDs (CRIDs)

SMAP Level-1 through Level-3 data file names include a Composite Release ID (CRID) that represents changes to any data processing condition that might impact SMAP products. The CRID incorporates algorithm, software, and other parameters involved in data processing. Note: The major version does not necessarily coincide with the CRID major version.

Files are named according to the following convention, with the CRID shown in bold:

SMAP_L1A_RADIOMETER_[Orbit#]_[A/D]_yyyymmddThhmmss_RLVvvv_NNN.[ext]

Where:

Variable

Description

R

Release

L

Launch Indicator (1: SMAP Standard Data)

V

1-Digit CRID Major Version Number

vvv

3-Digit CRID Minor Version Number

Science Version IDs

SMAP Level-4 data file names include a Science Version ID that, like the Composite Release ID for Level-1 through -3 data, represents changes to any data processing condition that might impact SMAP product results.

Files are named similar to the following convention, with the Science Version ID shown in bold:

SMAP_L4_C_MDL_yyyymmddThhmmss_VLMmmm_NNN.[ext]

Where:

Variable

Description

V

Science Version

L

Launch Indicator (b: Beta-quality data, v: Validated data)

M

1-Digit Major Science Version Number

mmm

3-Digit Minor Science Version Number

Maturity States

  • Beta — Indicates data sets using a developing algorithm with updates anticipated.
  • Validated — Data sets are upgraded to Validated once the Beta algorithm is verified by the algorithm team and validated by the validation team.

Validation Stages

A stage (1, 2, or 3) may be appended to Validated product maturity codes. The following table describes the validation stages.

Validation Stage

Description

Stage 1

Product accuracy is estimated using a small number of independent measurements obtained from selected locations, time periods, and ground-truth/field program efforts.

Stage 2

Product accuracy is assessed over a widely distributed set of locations and time periods via several ground-truth and validation efforts.

Stage 3

Product accuracy is assessed, and the uncertainties in the product are well established via independent measurements made in a systematic and statistically robust way that represents global conditions.

Temporal Coverage

Dates

All dates on this page are listed as four-digit year followed by two-digit month and two-digit day, such as 2015-12-31.

Times

Times are listed as two-digit hour followed by two-digit minute , such as 17:24. Times are in Coordinated Universal Time (UTC), which is also known as Greenwich Mean Time (GMT) and/or "Z" or "Zulu Time."

Composite Release IDs (CRIDs)

SMAP Level-1 through Level-3 data file names include a Composite Release ID (CRID) that represents changes to any data processing condition that might impact SMAP products. The CRID incorporates algorithm, software, and other parameters involved in data processing. Note: The major version does not necessarily coincide with the CRID major version.

Files are named according to the following convention, with the CRID shown in bold:

SMAP_L1A_RADIOMETER_[Orbit#]_[A/D]_yyyymmddThhmmss_RLVvvv_NNN.[ext]

Where:

Variable Description
R/N Release/Near Real-Time
L Launch Indicator (1: SMAP Standard Data)
V 1-Digit CRID Major Version Number
vvv 3-Digit CRID Minor Version Number

Science Version IDs

SMAP Level-4 data file names include a Science Version ID that, like the Composite Release ID for Level-1 through -3 data, represents changes to any data processing condition that might impact SMAP product results.

Files are named similar to the following convention, with the Science Version ID shown in bold:

SMAP_L4_C_MDL_yyyymmddThhmmss_VLMmmm_NNN.[ext]

Where:

Variable Description
V Science Version
L Launch Indicator (b: Beta-quality data, v: Validated data)
M 1-Digit Major Science Version Number
mmm 3-Digit Minor Science Version Number

Maturity States

  • Beta — Indicates data sets using a developing algorithm with updates anticipated.
  • Validated — Data sets are upgraded to Validated once the Beta algorithm is verified by the algorithm team and validated by the validation team.

Validation Stages

Additionally, a stage (1, 2, or 3) may be appended to Validated product maturity codes. The following table describes the validation stages.

Validation Stage Description
Stage 1 Product accuracy is estimated using a small number of independent measurements obtained from selected locations, time periods, and ground-truth/field program efforts.
Stage 2 Product accuracy is assessed over a widely distributed set of locations and time periods via several ground-truth and validation efforts.
Stage 3 Product accuracy is assessed, and the uncertainties in the product are well established via independent measurements made in a systematic and statistically robust way that represents global conditions.

Temporal Coverage

Dates

All dates on this page are listed as four-digit year followed by two-digit month and two-digit day, such as 2015-12-31.

Times

Times are listed as two-digit hour followed by two-digit minute , such as 17:24. Times are in Coordinated Universal Time (UTC), which is also known as Greenwich Mean Time (GMT) and/or "Z" or "Zulu Time."