Datasets - Data to be validated

The following datasets can be validated within the QA4SM tool. These datasets are available in the "data" section of the validate page.

Dataset Details Versions supported with Time Range Covered Data availability Citation Filters
C3S The C3S long-term data record provides active, passive and combined (active+passive) soil moisture data on a daily, dekadal and monthly basis. Observations are provided on a quarter degree grid. For more information, please visit the Climate Data Store.
  • v201706 (C3S from June 2017)
    From: 1978-11-01
    To: 2017-06-30
  • v201812 (C3S from December 2018)
    From: 1978-11-01
    To: 2018-12-31
  • v201912 (C3S from December 2019)
    From: 1978-11-01
    To: 2019-12-31
The data can be downloaded from the Climate Data Store. See Climate Data Store
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
  • Data with no inconsistencies detected (flag = 0): Data flag = 0 indicates good data, no inconsistencies detected
  • Not freezing and no snow-cover (flag != 1): Data flag != 1 indicates temperature > 0 C and no snow cover
  • No dense vegetation (flag != 2): Data flag != 2 indicates no places with dense vegetation
  • Ascending mode only: Data captured when satellite was ascending
  • Descending mode only: Data captured when satellite was descending
ESA CCI SM active see ESA CCI SM combined
  • v04.5
    From: 1991-08-05
    To: 2018-12-31
  • v05.2
    From: 1991-08-05
    To: 2018-12-31
see ESA CCI SM combined see ESA CCI SM combined
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
  • Data with no inconsistencies detected (flag = 0): Data flag = 0 indicates good data, no inconsistencies detected
  • Not freezing and no snow-cover (flag != 1): Data flag != 1 indicates temperature > 0 C and no snow cover
  • No dense vegetation (flag != 2): Data flag != 2 indicates no places with dense vegetation
  • Ascending mode only: Data captured when satellite was ascending
  • Descending mode only: Data captured when satellite was descending
ESA CCI SM combined The ESA CCI SM long-term data record provides active, passive and combined (active+passive) on a daily basis. Observations are provided on a quarter degree grid. For more information on the ESA CCI SM product, please see the product homepage.
  • v04.4
    From: 1978-11-01
    To: 2018-06-30
  • v04.5
    From: 1978-11-01
    To: 2018-12-31
  • v04.7
    From: 1978-11-01
    To: 2019-12-31
  • v05.2
    From: 1978-11-01
    To: 2019-12-31
Register at ESA CCI, then download through FTP. See CCI Publications Page
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
  • Data with no inconsistencies detected (flag = 0): Data flag = 0 indicates good data, no inconsistencies detected
  • Not freezing and no snow-cover (flag != 1): Data flag != 1 indicates temperature > 0 C and no snow cover
  • No dense vegetation (flag != 2): Data flag != 2 indicates no places with dense vegetation
  • Ascending mode only: Data captured when satellite was ascending
  • Descending mode only: Data captured when satellite was descending
ESA CCI SM passive see ESA CCI SM combined
  • v04.5
    From: 1978-11-01
    To: 2018-12-31
  • v05.2
    From: 1978-11-01
    To: 2019-12-31
see ESA CCI SM combined see ESA CCI SM combined
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
  • Data with no inconsistencies detected (flag = 0): Data flag = 0 indicates good data, no inconsistencies detected
  • Not freezing and no snow-cover (flag != 1): Data flag != 1 indicates temperature > 0 C and no snow cover
  • No dense vegetation (flag != 2): Data flag != 2 indicates no places with dense vegetation
  • Ascending mode only: Data captured when satellite was ascending
  • Descending mode only: Data captured when satellite was descending
H-SAF ASCAT SSM CDR The ASCAT dataset from the EUMETSAT H-SAF portal provides global daily soil moisture observations on a discrete global grid (DGG) with a spatial resolution of 25 km. Observations are provided from the ASCAT instrument on-board both Metop-A and Metop-B (more information).
  • H113
    From: 2007-01-02
    To: 2017-12-31
The data can be downloaded from the product homepage. See section 5.2 of this document
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
  • Metop-A observations: sat_id flag is metop-a
  • Metop-B observations: sat_id flag is metop-b
  • Soil not frozen (or state not known): ssf flag is "unfrozen" or "unknown"
  • No confidence flags raised: No confidence flags (indicating problems with the data) are set
  • No processing flags raised: No processing flags (indicating data values are changed based on thresholds) are set
SMAP level 3 The NASA SMAP level 3 data set provides global daily soil moisture observations at a 36 km resolution from the SMAP sensor (more information).
  • v5 PM/ascending
    From: 2015-03-31
    To: 2018-12-04
  • v6 PM/ascending
    From: 2015-03-31
    To: 2020-05-23
The data can be downloaded from the product homepage here. Click here
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
SMOS IC The SMOS IC product generated by INRA and CESBIO provides global soil moisture and VOD based on the two parameter inversion of the L-MEB model.
  • V.105 Ascending
    From: 2010-01-12
    To: 2018-12-31
The data can be downloaded from the product homepage. See this page.
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
  • Soil moisture values are retrieved and recommended: Soil moisture values are retrieved and recommended (Quality_Flag == 0)
  • Soil not frozen: Scene_Flag 00001000 is not set, meaning: Soil_Temperature_Level1 >= 273
  • Scene not polluted: Scene_Flag 00000100 not set, meaning: water+urban+ice <= 10% of the pixel
  • RMSE of brightness temperature within acceptable limits (< 12 K): Processing_Flags ! = 00000001
  • Exclude moderate topo: Scene_Flag 00000001 not set
  • Exclude strong topo: Scene_Flag 00000010 is not set

Datasets - Reference Data

The following datasets can be used as a reference within the QA4SM tool. These datasets are available in the "reference" section of the validate page.

Dataset Details Versions supported with Time Range Covered Data availability Citation Filters
ERA5 ERA5 is a global reanalysis product provided by ECMWF. It provides global, sub-daily simulations of variables for land, atmosphere and ocean waves. The downloaded original 6-hourly (starting at 0:00 UTC) images of ERA5 Volumetric Soil Moisture and Soil Temperature with a spatial resolution of 0.25° Lat. * 0.25° Lon were converted into a time series format via daily averages. The ERA5 dataset starts in 1979. The version number used in QA4SM indicates the date when the original data was downloaded. For more details about ERA5 please see ECMWF Confluence - ERA5 Documentation
  • v20190613 (snapshot of the reanalysis dataset from 2019-06-13)
    From: 1979-01-01
    To: 2019-03-31
Data is freely available with a CDS account. See ECMWF Confluence - ERA5 Download Click here
  • Soil not frozen: Corresponding depth soil temperature > 1.0 C
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
ERA5-Land ERA5-Land has been produced by replaying the land component of the ECMWF ERA5 climate reanalysis. The downloaded original 6-hourly (starting at 0:00 UTC) images of ERA5-Land Volumetric Soil Moisture and Soil Temperature with a spatial resolution of 0.1° Lat. * 0.1° Lon were converted into a time series format from daily averages. ERA5-Land is available from January 2001 onward. The Soil Temperature variable (stl1) is used to mask Soil Moisture (swvl1) under frozen conditions if selected. The version number used in QA4SM indicates the date when the original data was downloaded. For more details please see ECMWF Confluence - ERA5-Land Documentation
  • v20190904 (snapshot of the reanalysis dataset from 2019-09-04)
    From: 2001-01-01
    To: 2019-04-30
Data is freely available with a CDS account. See Copernicus Climate Data Store Confluence - ERA5-Land Download Click here
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
  • Soil not frozen: Corresponding depth soil temperature > 1.0 C
GLDAS GLDAS is a land surface model (LSM) which provides soil moisture data at different depths. Different versions are available for different time periods. For more information, visit the LDAS website: NASA Land Data Assimilation Systems Website
  • NOAH025 3H.2.1 (Version 2.1)
    From: 2000-01-01
    To: 2017-12-31
Data is freely available after registration here for version 2.1 Click here
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
  • Soil not frozen and no snow-cover: Corresponding depth soil temperature > 1.0 C and Snow depth water equivalent < 0.001
ISMN The ISMN provides in-situ soil moisture data from over 2600 monitoring stations worldwide. The data is harmonised and quality controlled to ensure the highest quality data is provided through the portal. Data is provided from 1952 to present day (more information).
  • 20180712 mini testset (Test dataset with only 4 stations)
    Time coverage is station dependent
  • 20191211 global (ISMN from 2019-12-11)
    Time coverage is station dependent
Data is freely available after registration here. Terms and conditions, readme (v20180830), and readme (v20190222)
  • Variable in valid geophysical range: Compared variable is checked for NaNs and invalid values.
  • Quality flag is "good" (G): Soil moisture quality flag is "G" for good.
  • Use ISMN networks:: Click 'select' to chose the ISMN networks to use in this validation
  • Use measurements at given depth:: Click 'select' to introduce soil moisture depths