THE ESTIMATION AND SCALING OF LAND-SURFACE FLUXES OF LATENT AND SENSIBLE-HEAT WITH REMOTELY SENSED DATA OVER A GRASSLAND SITE

Persistent Link:
http://hdl.handle.net/10150/617639
Title:
THE ESTIMATION AND SCALING OF LAND-SURFACE FLUXES OF LATENT AND SENSIBLE-HEAT WITH REMOTELY SENSED DATA OVER A GRASSLAND SITE
Author:
Humes, Karen Sue; Sorooshian, Soroosh
Affiliation:
Department of Hydrology & Water Resources, The University of Arizona
Publisher:
Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ)
Issue Date:
1993
Rights:
Copyright © Arizona Board of Regents
Collection Information:
This title from the Hydrology & Water Resources Technical Reports collection is made available by the Department of Hydrology & Atmospheric Sciences and the University Libraries, University of Arizona. If you have questions about titles in this collection, please contact repository@u.library.arizona.edu.
Abstract:
The overall topic of the research described in this dissertation was the partitioning of available energy at the Earth's surface into sensible and latent heat flux, with an emphasis on the development of techniques which utilize remotely sensed data. One of the major objectives was to investigate the modification of existing techniques, developed over agricultural surfaces, to "natural" ecosystems (i.e., non -agricultural vegetation types with variable and incomplete canopy cover). Ground -based measurements of surface fluxes, vegetation cover, and surface and root -zone soil moisture from the First ISLSCP (International Land Surface Climatology Program) Field Experiment (FIFE) were used to examine the factors controlling the partitioning of energy at ground stations with contrasting surface characteristics. Utilizing helicopter -based and satellite -based data acquired directly over ground -based flux stations at the FINE experimental area, relatively simple algorithms were developed for estimating the soil heat flux and sensible heat flux from remotely sensed data. The root mean square error (RMSE) between the sensible heat flux computed with the remotely sensed data and the sensible heat flux measured at the ground stations was 33 Wm 2. These algorithms were then applied on a pixel -by -pixel basis to data from a Landsat -TM (Thematic Mapper) scene acquired over the FIFE site on August 15, 1987 to produce spatially distributed surface energy- balance components for the FIFE site. A methodology for quantifying the effect of spatial scaling on parameters derived from remotely sensed data was presented. As an example of the utility of this approach, NDVI values for the 1,IFE experimental area were computed with input data of variable spatial resolution. The differences in the values of NDVI computed at different spatial resolutions were accurately predicted by an equation which quantified those differences in terms of variability in input observations.
Keywords:
Dissertations, Academic; Hydrology; Remote sensing
Series/Report no.:
Technical Reports on Hydrology and Water Resources, No. 93-030
Sponsors:
It would not have been possible for me to pursue this area of research without a fellowship from the NASA Graduate Student Research Program and a grant from the NASA Earth Observing System Program (NAG2425). I am particularly indebted to Robert Gurney for his encouragement and technical guidance during my early years in the GSRP program. I owe Ghassem Asrar very special thanks for both his role at NASA Headquarters and his role in the implementation of the FIFE experiment. I am also very grateful for the support provided by the John and Margaret Harshbarger Fellowship.

Full metadata record

DC FieldValue Language
dc.contributor.authorHumes, Karen Sueen
dc.contributor.authorSorooshian, Sorooshen
dc.date.accessioned2016-07-27T23:04:33Z-
dc.date.available2016-07-27T23:04:33Z-
dc.date.issued1993-
dc.identifier.urihttp://hdl.handle.net/10150/617639-
dc.description.abstractThe overall topic of the research described in this dissertation was the partitioning of available energy at the Earth's surface into sensible and latent heat flux, with an emphasis on the development of techniques which utilize remotely sensed data. One of the major objectives was to investigate the modification of existing techniques, developed over agricultural surfaces, to "natural" ecosystems (i.e., non -agricultural vegetation types with variable and incomplete canopy cover). Ground -based measurements of surface fluxes, vegetation cover, and surface and root -zone soil moisture from the First ISLSCP (International Land Surface Climatology Program) Field Experiment (FIFE) were used to examine the factors controlling the partitioning of energy at ground stations with contrasting surface characteristics. Utilizing helicopter -based and satellite -based data acquired directly over ground -based flux stations at the FINE experimental area, relatively simple algorithms were developed for estimating the soil heat flux and sensible heat flux from remotely sensed data. The root mean square error (RMSE) between the sensible heat flux computed with the remotely sensed data and the sensible heat flux measured at the ground stations was 33 Wm 2. These algorithms were then applied on a pixel -by -pixel basis to data from a Landsat -TM (Thematic Mapper) scene acquired over the FIFE site on August 15, 1987 to produce spatially distributed surface energy- balance components for the FIFE site. A methodology for quantifying the effect of spatial scaling on parameters derived from remotely sensed data was presented. As an example of the utility of this approach, NDVI values for the 1,IFE experimental area were computed with input data of variable spatial resolution. The differences in the values of NDVI computed at different spatial resolutions were accurately predicted by an equation which quantified those differences in terms of variability in input observations.en
dc.description.sponsorshipIt would not have been possible for me to pursue this area of research without a fellowship from the NASA Graduate Student Research Program and a grant from the NASA Earth Observing System Program (NAG2425). I am particularly indebted to Robert Gurney for his encouragement and technical guidance during my early years in the GSRP program. I owe Ghassem Asrar very special thanks for both his role at NASA Headquarters and his role in the implementation of the FIFE experiment. I am also very grateful for the support provided by the John and Margaret Harshbarger Fellowship.en
dc.language.isoen_USen
dc.publisherDepartment of Hydrology and Water Resources, University of Arizona (Tucson, AZ)en
dc.relation.ispartofseriesTechnical Reports on Hydrology and Water Resources, No. 93-030en
dc.rightsCopyright © Arizona Board of Regentsen
dc.sourceProvided by the Department of Hydrology and Water Resources.en
dc.subjectDissertations, Academicen
dc.subjectHydrologyen
dc.subjectRemote sensingen
dc.titleTHE ESTIMATION AND SCALING OF LAND-SURFACE FLUXES OF LATENT AND SENSIBLE-HEAT WITH REMOTELY SENSED DATA OVER A GRASSLAND SITEen_US
dc.typetexten
dc.typeTechnical Reporten
dc.contributor.departmentDepartment of Hydrology & Water Resources, The University of Arizonaen
dc.description.collectioninformationThis title from the Hydrology & Water Resources Technical Reports collection is made available by the Department of Hydrology & Atmospheric Sciences and the University Libraries, University of Arizona. If you have questions about titles in this collection, please contact repository@u.library.arizona.edu.en
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