RoyTooseDerksenEtAl2017

Référence

Roy, A., Toose, P., Derksen, C., Rowlandson, T., Berg, A.A., Lemmetyinen, J., Royer, A., Tetlock, E., Helgason, W. and Sonnentag, O. (2017) Spatial variability of L-Band brightness temperature during freeze/thaw events over a prairie environment. Remote Sensing, 9(9). (Scopus )

Résumé

Passive microwave measurements from space are known to be sensitive to the freeze/thaw (F/T) state of the land surface. These measurements are at a coarse spatial resolution (~15-50 km) and the spatial variability of the microwave emissions within a pixel can have important effects on the interpretation of the signal. An L-band ground-based microwave radiometer campaign was conducted in the Canadian Prairies during winter 2014-2015 to examine the spatial variability of surface emissions during frozen and thawed periods. Seven different sites within the Kenaston soil monitoring network were sampled five times between October 2014 and April 2015 with a mobile ground-based L-band radiometer system at approximately monthly intervals. The radiometer measurements showed that in a seemingly homogenous prairie landscape, the spatial variability of brightness temperature (TB) is non-negligible during both frozen and unfrozen soil conditions. Under frozen soil conditions, TB was negatively correlated with soil permittivity (εG). This correlation was related to soil moisture conditions before the main freezing event, showing that the soil ice volumetric content at least partly affects TB. However, because of the effect of snow on L-Band emission, the correlation between TB and εG decreased with snow accumulation. When compared to satellite measurements, the average TB of the seven plots were well correlated with the Soil Moisture Ocean Salinity (SMOS) TB with a root mean square difference of 8.1 K and consistent representation of the strong F/T signal (i.e., TB increases and decreases when soil freezing and thawing, respectively). This study allows better quantitative understanding of the spatial variability in L-Band emissions related to landscape F/T, and will help the calibration and validation of satellite-based F/T retrieval algorithms. © 2017 by the authors.

Format EndNote

Vous pouvez importer cette référence dans EndNote.

Format BibTeX-CSV

Vous pouvez importer cette référence en format BibTeX-CSV.

Format BibTeX

Vous pouvez copier l'entrée BibTeX de cette référence ci-bas, ou l'importer directement dans un logiciel tel que JabRef .

@ARTICLE { RoyTooseDerksenEtAl2017,
    AUTHOR = { Roy, A. and Toose, P. and Derksen, C. and Rowlandson, T. and Berg, A.A. and Lemmetyinen, J. and Royer, A. and Tetlock, E. and Helgason, W. and Sonnentag, O. },
    TITLE = { Spatial variability of L-Band brightness temperature during freeze/thaw events over a prairie environment },
    JOURNAL = { Remote Sensing },
    YEAR = { 2017 },
    VOLUME = { 9 },
    NUMBER = { 9 },
    NOTE = { cited By 1 },
    ABSTRACT = { Passive microwave measurements from space are known to be sensitive to the freeze/thaw (F/T) state of the land surface. These measurements are at a coarse spatial resolution (~15-50 km) and the spatial variability of the microwave emissions within a pixel can have important effects on the interpretation of the signal. An L-band ground-based microwave radiometer campaign was conducted in the Canadian Prairies during winter 2014-2015 to examine the spatial variability of surface emissions during frozen and thawed periods. Seven different sites within the Kenaston soil monitoring network were sampled five times between October 2014 and April 2015 with a mobile ground-based L-band radiometer system at approximately monthly intervals. The radiometer measurements showed that in a seemingly homogenous prairie landscape, the spatial variability of brightness temperature (TB) is non-negligible during both frozen and unfrozen soil conditions. Under frozen soil conditions, TB was negatively correlated with soil permittivity (εG). This correlation was related to soil moisture conditions before the main freezing event, showing that the soil ice volumetric content at least partly affects TB. However, because of the effect of snow on L-Band emission, the correlation between TB and εG decreased with snow accumulation. When compared to satellite measurements, the average TB of the seven plots were well correlated with the Soil Moisture Ocean Salinity (SMOS) TB with a root mean square difference of 8.1 K and consistent representation of the strong F/T signal (i.e., TB increases and decreases when soil freezing and thawing, respectively). This study allows better quantitative understanding of the spatial variability in L-Band emissions related to landscape F/T, and will help the calibration and validation of satellite-based F/T retrieval algorithms. © 2017 by the authors. },
    AFFILIATION = { Centre d'Applications et de Recherches en Télédétection (CARTEL), Université de Sherbrooke, 2500 boul. Université, Sherbrooke, QC, Canada; Centre d'études Nordiques, Université Laval, Québec, QC, Canada; Département de Géographie, Université de Montréal, Montréal, QC, Canada; Climate Research Division, Environment and Climate Change Canada, Toronto, ON, Canada; Department of Geography, University of Guelph, Guelph, ON, Canada; Finnish Meteorological Institute, Helsinki, Finland; Environment and Climate Change Canada, Sasktoon, SK, Canada; Civil, Geological and Environmental Engineering, University of Saskatchewan, Saskatoon, SK, Canada },
    ART_NUMBER = { 894 },
    AUTHOR_KEYWORDS = { Freeze/thaw; L-Band; SMOS; Snow density; Soil permittivity; Spatial variability },
    DOCUMENT_TYPE = { Article },
    DOI = { 10.3390/rs9090894 },
    SOURCE = { Scopus },
    URL = { https://www.scopus.com/inward/record.uri?eid=2-s2.0-85029355072&doi=10.3390%2frs9090894&partnerID=40&md5=1df724c5556fa6d17d9455694ce02b0f },
}

********************************************************** ***************** Facebook Twitter *********************** **********************************************************

Abonnez-vous à
l'Infolettre du CEF!

********************************************************** ************* Écoles d'été et formation **************************** **********************************************************

Écoles d'été et formations

********************************************************** ***************** Pub - Symphonies_Boreales ****************** **********************************************************

********************************************************** ***************** Boîte à trucs *************** **********************************************************

CEF-Référence
La référence vedette !

Jérémie Alluard (2016) Les statistiques au moments de la rédaction 

  • Ce document a pour but de guider les étudiants à intégrer de manière appropriée une analyse statistique dans leur rapport de recherche.

Voir les autres...