Zur Seitenansicht
 

Titelaufnahme

Titel
Evaluation of a MetOp ASCATDerived Surface Soil Moisture Product in Tundra Environments
VerfasserHögström, Elin ; Heim, Birgit ; Bartsch, Annett ; Bergstedt, Helena ; Pointner, Georg
Erschienen in
Journal of Geophysical Research, Hoboken, 2018, Jg. 123, H. 12, S. 1-16
ErschienenHoboken : Wiley, 2018
SpracheEnglisch
DokumenttypAufsatz in einer Zeitschrift
Schlagwörter (EN)radar / tundra / soil moisture / C band / Arctic
Projekt-/ReportnummerDK W1237-N23
Projekt-/ReportnummerGA282700
Projekt-/ReportnummerBG-2017-1
ISSN2169-9003
URNurn:nbn:at:at-ubs:3-10931 Persistent Identifier (URN)
DOI10.1029/2018JF004658 
Zugriffsbeschränkung
 Das Werk ist frei verfügbar
Dateien
Evaluation of a MetOp ASCATDerived Surface Soil Moisture Product in Tundra Environments [4.79 mb]
Links
Nachweis
Klassifikation
Zusammenfassung (Englisch)

Satellitederived surface soil moisture data are available for the Arctic, but detailed validation is still lacking. Previous studies have shown low correlations between in situ and modeled data. It is hypothesized that soil temperature variations after soil thaw impact MetOp ASCAT satellitederived surface soil moisture (SSM) measurements in wet tundra environments, as C band backscatter is sensitive to changes in dielectric properties. We compare in situ measurements of water content within the active layer at four sites across the Arctic in Alaska (Barrow, Sagwon, Toolik) and Siberia (Tiksi), taken in the spring after thawing and in autumn prior to freezing. In addition to the longterm measurement fields, where sensors are installed deeper in the ground, we designed a monitoring setup for measuring moisture very close to the surface in the Lena River Delta, Siberia. The volumetric water content (VWC) and soil temperature sensors were placed in the moss organic layer in order to account for the limited penetration depth of the radar signal. ASCAT SSM variations are generally very small, in line with the low variability of in situ VWC. Shortterm changes after complete thawing of the upper organic layer, however, seem to be mostly influenced by soil temperature. Correlations between SSM and in situ VWC are generally very low, or even negative. Mean standard deviation matching results in a comparably high rootmeansquare error (on average 11%) for predictions of VWC. Further investigations and measurement networks are needed to clarify factors causing temporal variation of C band backscatter in tundra regions.

Statistik
Das PDF-Dokument wurde 2 mal heruntergeladen.
Lizenz
CC-BY-Lizenz (4.0)Creative Commons Namensnennung 4.0 International Lizenz