The International Soil Moisture Network: serving Earth system science for over a decade

Abstract

Abstract. In 2009, the International Soil Moisture Network (ISMN) was initiated as a community effort, funded by the European Space Agency, to serve as a centralised data hosting facility for globally available in situ soil moisture measurements (Dorigo et al., 2011b, a). The ISMN brings together in situ soil moisture measurements collected and freely shared by a multitude of organisations, harmonises them in terms of units and sampling rates, applies advanced quality control, and stores them in a database. Users can freely retrieve the data from this database through an online web portal (https://ismn.earth/en/, last access: 28 October 2021). Meanwhile, the ISMN has evolved into the primary in situ soil moisture reference database worldwide, as evidenced by more than 3000 active users and over 1000 scientific publications referencing the data sets provided by the network. As of July 2021, the ISMN now contains the data of 71 networks and 2842 stations located all over the globe, with a time period spanning from 1952 to the present. The number of networks and stations covered by the ISMN is still growing, and approximately 70 % of the data sets contained in the database continue to be updated on a regular or irregular basis. The main scope of this paper is to inform readers about the evolution of the ISMN over the past decade, including a description of network and data set updates and quality control procedures. A comprehensive review of the existing literature making use of ISMN data is also provided in order to identify current limitations in functionality and data usage and to shape priorities for the next decade of operations of this unique community-based data repository.

A global 1‐km downscaled SMAP soil moisture product based on thermal inertia theory

“…The purpose of developing the ISMN database was to validate and improve global remote sensing/LSM products. A number of investigations have been conducted to evaluate the SM measurements by ISMN (Dorigo et al., 2011, 2013, 2021; Gruber et al., 2013; Schaefer et al., 2007). In this study, we acquired the 0‐to‐5‐cm soil layer SM measurements for 427 stations from eight dense SM networks from https://ismn.geo.tuwien.ac.at/.…”

COSMOS-Europe: a European network of cosmic-ray neutron soil moisture sensors

“…Similar to COSMOS-Europe, several other large-scale COSMOS networks already exist in the USA, Australia, and India. The obvious next step is to build on the methods developed in this study to create a global network of continental COSMOS networks, similar to the FLUXNET initiative for eddy covariance measurements of land-atmosphere exchange fluxes (FLUXNET, 2021) or the International Soil Moisture Network (ISMN) that provides in situ soil moisture data from 2842 stations worldwide (Dorigo et al, 2021). Initial networking efforts in this direction have already been undertaken.…”

Towards Consistent Soil Moisture Records from China’s FengYun-3 Microwave Observations

“…It was established by the Vienna University of Science and Technology in 2009. The SM is collected from different regions and climate conditions across the globe and uses quality control procedures to filter and label the dataset [60,63]. The point-scale representation of the station datasets and the area-averaged gridded satellite observations introduces mismatched uncertainties in the comparisons [64].…”