DOI: 10.25592/uhhfdm.16509
title: ASCAT Global Maps of daily running 5-day mean surface soil moisture - extension 2024

description: <strong>Abstract:</strong> The soil moisture time series data of the extension of the EUMETSAT H-SAF product H119: H120 based on MetOp-B, and -C ASCAT data, processing version v7 (https://doi.org/10.15770/EUM_SAF_H_0009), are converted into geographic maps (cartesian grid) of daily running 5-day average/composite soil moisture (SM) distribution separately for ascending and descending overpasses. Two different 5-day SM distributions are given: one is based solely on nominally computed SM, the other one includes also those SM values which were negative (down to -25%, correction flag = 1) or positive (up to 125%, correction flag = 2) but set to 0% and 100%, respectively. All data are interpolated into a cartesian grid of x- and y-dimensions of original grid. For more information see the respective global attribute in the netCDF file.

<strong>TableOfContents:</strong> soil moisture; soil moisture noise; soil moisture extended; soil moisture extended noise; soil moisture status flag; number of overpasses per grid cell; historic probability of snow cover; historic probability of frozen land; inundation and wetland fraction; topographic complexity; soil porosity LDAS; soil porosity HWSD

<strong>Technical Info:</strong> dimensons: 3207 columns x 1599 rows x unlimited; temporalExtent_startDate: 2022-01-01; temporalExtent_endDate: 2024-07-31; temporalResolution: daily; spatialResolution: 0.1125; spatialResolutionUnit: degrees; horizontalResolutionXdirection: 0.1125; horizontalResolutionXdirectionUnit: degrees; horizontalResolutionYdirection: 0.1125; horizontalResolutionYdirectionUnit: degrees; verticalResolution: none; verticalResolutionUnit: none; verticalStart: none; verticalEnd: none; instrumentName: Advanced SCATterometer (ASCAT); instrumentType: C-band microwave_scatterometer; instrumentLocation: Meteorological Operational Satellite (MetOp-B, MetOp-C); instrumentProvider: EUMETSAT, ESA; License: The following applies to the original product: All intellectual property rights of the HSAF products belong to EUMETSAT. The use of these products is granted to every user, free of charge. If users wish to use these products, EUMETSAT's copyright credit must be shown by displaying the words "Copyright EUMETSAT" under each of the products shown. EUMETSAT offers no warranty and accepts no liability in respect of the HSAF products. EUMETSAT neither commits to nor guarantees the continuity, availability, or quality or suitability for any purpose of, the HSAF products. 

<strong>Methods:</strong> For a description of the methods used to obtain the 5-day average / composite data we refer to the global attributes of the netCDF files. For the methods used for the native soil moisture time series please see:  [1] Wagner, W., et al.: A method for estimating soil moisture from ERS scatterometer and soil data, Rem. Sens. Environ., 70(2), 191-207, 1999. doi: 10.1016/S0034-4257(99)00036-X; [2] Naeimi, V., et al.: An Improved Soil Moisture Retrieval Algorithm for ERS and METOP Scatterometer Observations, IEEE Trans. Geosci. Rem. Sens., 47(7), 1999-2013, 2009. doi:10.1109/TGRS.2008.2011617; [3] Naeimi, V., et al.: ASCAT Surface State Flag (SSF): Extracting Information on Surface Freeze/Thaw Conditions From Backscatter Data Using an Empirical Threshold-Analysis Algorithm, IEEE Trans. Geosci. Rem. Sens., 50(7), 2566-2582, 2012. doi: 10.1109/TGRS.2011.2177667; [4] Product User Manual: H SAF, Product User Manual (PUM) Metop ASCAT Surface Soil Moisture Climate Data Record v7 12.5 km sampling (H119) and Extension (H120), v0.2, 2022; [5] Algorithm Theoretical Basis Document: H SAF, Algorithm Theoretical Baseline Document (ATBD) Metop ASCAT Surface Soil Moisture Climate Data Record v7 12.5 km sampling (H119) and Extension (H120), v0.1, 2021; [6] Product Validation Report: H SAF, Product Validation Report (PVR) Metop ASCAT Surface Soil Moisture Climate Data Record v7 12.5 km sampling (H119) and Extension (H120), v1.1, 2022.

<strong>Units:</strong> units for all variables (see TableOfContents): percent, percent, percent, percent, 1, 1, percent, percent, percent, percent, m<sup>3</sup>/m<sup>3</sup>, m<sup>3</sup>/m<sup>3</sup>

<strong>geoLocations:</strong> westBoundLongitude: -180.0 degrees East; eastBoundLongitude: 180.0 degrees East; southBoundLongitude: -90.0 degrees North; northBoundLongitude: 90.0 degrees North; geoLocationPlace: global over land

<strong>Size:</strong> 730 files per year [note: there are 2 files per day, one for the ascending, one for the descending overpasses]; ~61.569 MegaByte per file; ~43.892 GigaByte per year (provided as two zip-files per year)

<strong>Format:</strong> netCDF

<strong>DataSources:</strong>

Original Data as time series on a 12.5 km DGG Grid: https://hsaf.meteoam.it/Products/Detail?prod=H120 (last access: 2024-11-29); this original product comes with the following notion: "All intellectual property rights of the HSAF products belong to EUMETSAT. The use of these products is granted to every user, free of charge. If users wish to use these products, EUMETSAT's copyright credit must be shown by displaying the words "Copyright EUMETSAT" under each of the products shown. EUMETSAT offers no warranty and accepts no liability in respect of the HSAF products. EUMETSAT neither commits to nor guarantees the continuity, availability, or quality or suitability for any purpose of, the HSAF products."

See also: http://hsaf.meteoam.it; https://hsaf.meteoam.it/Products/Detail?prod=H120

<strong>Contact:</strong> stefan.kern (at) uni-hamburg.de

<strong>Web page: </strong>https://www.cen.uni-hamburg.de/en/icdc/data/land/ascat-soilmoisture.html
description: The data are distributed under CC-BY-SA-NC-4.0