Dielectric database of organic Arctic soils (DDOAS)

Igor Savin,Yuriy Lukin,Zdenek Ruzicka,Konstantin Muzalevskiy,Andrey Karavayskiy,Valery Mironov,Sergey Fomin

doi:10.5194/essd-12-3481-2020

Abstract

Abstract. This article presents a dielectric database of organic Arctic soils (DDOAS). The DDOAS was created based on the dielectric measurements of seven samples of organic-rich soils collected in various parts of the Arctic tundra: Yamal Peninsula, Taimyr Peninsula, Samoylov Island (all in the Russian Federation) and the northern slope of Alaska (US). The organic matter content (by weight) of the presented soil samples varied from 35 % to 90 %. The refractive index (RI) and normalised attenuation coefficient (NAC) were measured under laboratory conditions by the coaxial-waveguide method in the frequency range from ∼ 10 MHz to ∼ 16 GHz, while the moisture content changed from air-dry to field capacity, and the temperature changed from −40 to +25 ∘C. The total number of measured values of the RI and NAC contained in the database is more than 1.5 million. The created database can serve not only as a source of experimental data for the development of new soil dielectric models for the Arctic tundra but also as a source of training data for artificial intelligence satellite algorithms of soil moisture retrievals based on neural networks. The DDOAS is presented as Excel files. The files of the DDOAS are available on https://doi.org/10.5281/zenodo.3819912 (Savin and Mironov, 2020).

Highlights

The last 5-year (2015–2019) and 10-year (2010–2019) average surface air temperatures are the warmest in instrumental records
Nowadays SMAP (Soil Moisture Active Passive) and SMOS–MIRAS (Soil Moisture and Ocean Salinity–Microwave Imaging Radiometer with Aperture Synthesis) satellites radiometers operating at a frequency of 1.4 GHz (L band) (Wigneron et al, 2017), GCOM-W1–AMSR2 (Global Change Observation Mission–Advanced Microwave Scanning Radiometer) satellite radiometer operating at frequencies above 6.9 GHz (Gao et al, 2018), and MetOp–ASCAT (Meteorological Operational–Advanced Scatterometer) satellite radar operating at a frequency of 5.3 GHz (C band) (Brocca et al, 2017) are used to monitoring soil moisture in the layer thickness of 2.5–5.0 cm (Choudhury et al, 1979; Escorihuela et al, 2010)
The permittivity model of soils is an essential element in the physical-based algorithms of soil moisture retrieval with using remote sensing data of the current radiometric and radar satellites

Summary

Introduction

The last 5-year (2015–2019) and 10-year (2010–2019) average surface air temperatures are the warmest in instrumental records. None of the known dielectric models of organic soils (Bircher et al, 2016; Jin et al, 2017; Liu et al, 2013; Mironov et al, 2015a, 2015b, 2018, 2020; Mironov and Savin, 2015, 2016, 2019; Park et al, 2019) are used in operational algorithms of existing satellites to retrieve soil moisture in the Arctic regions. This work presents the unique database of the laboratory dielectric measurements of organic-soil samples These soil samples were taken in various places in the Arctic region. As was noted in Bircher et al (2016), Mironov’s temperature-dependent dielectric models for organic soils could be exploited in satellite data applications where negative temperatures are one of the major drivers (e.g. freeze–thaw, permafrost or snow-related products)

The test sites of collected soil samples

Soils samples preparation and method for measuring soil permittivity

Dataset description

Findings

Conclusions